I thought I would post some links to some Geography related stories that have been in the news over the past fews days, that may have been overlooked due to frequent reports of the ever changing situation in Japan and the Middle East. Unfortunatley, due to a mountain of other work to tackle, I don't have time to write about them but they are definetly worth reading if you can find a spare 5 minutes.
China tops global clean energy table. After a recent study compiled by the US Pew Environmental Group, China has remained the worlds leading investor in low carbon energy technology with an investment of £34.1bn in 2010. China is also the world's largest producer of wind and solar power units. Argentina topped the list, in terms of year-on-year growth, as it saw its investment grow by 568% since 2009. The USA, even though their investment increased by 51% slipped behind Germany, to 3rd place. The UK's investment dropped by 70% which means they are now ranked outside the top 10. The drastic drop in the UK's investment has been partly blamed on the uncertainity that was created by the formation of the coalition government. The report concluded that long term certainity, created by national policies and government commitment, was most attractive to investors and therefore countries who offered this, like China, India and Germany, have been most successful in securing and utilising investment for the development of low carbon technology. The low carbon energy sector does not include nuclear power and so statistics surrounding this were not included. Nuclear power attracted $243bn in 2010 which was an increase of 30% since 2009 and an huge increase of 630% from 2004 - it will be interesting though to see if and how investment figures will be influenced by the events in Japan........
UN report: Cities ignore Climate Change at their peril - This article is defintely worth reading as it links energy intensity and climate change to development and the population trends created by development. It also discusses not only the changes, the report concludes, that these trends will have on the environment and the climate but the impacts it will have on water supplies, energy provision, infrastructure, industrial production and public services.
Green Machine: Emissions cuts could save 280,000 lives. Another article that manages to link the energy module to population and it provides some very interesting statistics which am I am sure would be great to include in some essays relevant to the topic. It dicusses the other advantages, apart from the obvious environmental ones, that reductions in carbon dioxide emissions would have - many of which I must admit that I hadn't thought of.
These articles are very helpful if you are wanting to improve the links you can make between the population and energy module - especially the last two - and they all provide little bits of information and data that I am sure would look really good if you could sneak them into longer answer questions.
My Geography teacher has started an experiment which involves me writing about what I have learnt in my lessons and about any geographical news that interests me. My Geography teacher is also going to write a blog about what she teaches me (and therefore what I should have learnt!) and hopefully the two blogs will match up. The idea is that this will not only help me to consolidate what I learn but that it will also help fellow students do the same and keep up to date with current issues.
Tuesday, 29 March 2011
Sunday, 27 March 2011
Japan Earthquake: A Horizon Special with Iain Stewart
I have literally just watched this and it is without a doubt one of the best documentaries/TV programmes that I have watched on the Japanese Earthquake, if not the best. Not only does it cover the impacts of the earthquake and tsunami by presenting the shocking images from during and after these disasters hit but also goes on to explain why the earthquake was so big and why the tsunami was so destructive. The problems being experienced with nuclear power are explained whilst maps are used to represent where the worlds nuclear power plants are located in relation to the tectonic plant boundaries.The issues surrounding earthquake predictions are also presented and the documentary explains that, although at present we cannot predict earthquakes, we are getting better are pin pointing areas that are suseptible to large and destructive earthquakes. On top of all of this, the likelyhood of Tokyo experiencing the much dreaded 'Big One', after recent events, is explored.
This is definetly well worth watching and I would highly recommend it! You can catch it on BBC iplayer http://www.bbc.co.uk/iplayer/episode/b0101nq2/Horizon_Japan_Earthquake_A_Horizon_Special_with_Iain_Stewart/
This is definetly well worth watching and I would highly recommend it! You can catch it on BBC iplayer http://www.bbc.co.uk/iplayer/episode/b0101nq2/Horizon_Japan_Earthquake_A_Horizon_Special_with_Iain_Stewart/
60 minutes without electricty....
Like I mentioned on my last post, yesterday evening, between 8:30pm and 9:30pm, was Earth Hour and it has been estimated that 130 countries took part worldwide. As part of this global climate change campaign, in Scotland, more than 100 landmarks and iconic structures were plunged into darkness. Scotland was only one of many other countries that took part though........
I thought it would be quite interesting to see if my family could survive just 1 hour without electricity. So, how did we get on........
Well firstly, I didn't manage to persuade my brother to participate as, for him, the thought of spending an entire 60 minutes without his xbox was unbearable. Instead he decided to part take in the Human Achievement Hour (I am not making this up - it does exist and occurs at the same time as Earth Hour) which encourages people to " Leave your lights on to express your appreciation for the inventions and innovations that make today the best time to be alive and the recognition that future solutions require individual freedom not government coercion". The rest of my family decided to humour me in this challenge, even though they felt it was rather futile as they questionned the impact it would actually have on the global energy consumption (this is true but it kind wasn't the point). So, all the lights and appliances in my house went off, apart from the room my brother occupied, and the first thing I noticed, apart from the darkness, was how quiet everything was (a word of warning, if any of you decide to try this sometime, make sure you light candles before you turn the lights off, as trying to find them, along with matches, and then light them in the pitch black is interesting to say the least!). Unfortunately this peace and quiet didn't last long as my stepdad felt the need to moan about not being able to make a cup of tea literally every 5 minutes. My mum was rather more tolerant than I thought she would be, apart from complaining about the smell of the candles and frequently having to shout at the cat to prevent her from chasing the flickering light of the candles - honestly she was so close to setting herself a light on numerous occasions! I didn't find it too bad but this is partly because I don't really use many appliances and I often get bored of watching TV after 10 minutes. The only thing I hated (and I really did hate this) was the fact that with no lights I was enable to read - reading with a candle it particularly tricky. We therefore sat and had a few lively debates - all revolving around geographical topics and the environment - which I thought was great (although I don't think next time I will be allowed to choose the topics) and they become so lively that our hour was extended to a few as we just lost track of time. However, this was brought to an abrupt end, after my stepdad (gasping with thirst!) may a dash for the kettle - turning on all the lights on the way.
Overall, I didn't find it too bad and I think that I could have gone on longer than 1 hour. I missed the lights the most and I started to realise how restricted people who live without lighting must be - especially those who live near the equator and so experience a very quick transition from daylight to darkness. Did I learn anything from the experience? Well, yes I did. Apart from the fact that animals and candles possibly don't mix, I realised how much technology has killed conversation. It also made me think about the people who complete 8766 Earth Hours a year, as many in the world do not have access to electricity at all. I asked my mum what she thought and she said that she could not believe how much we were reliant on lights and how, despite having candles, we were very restricted to what we could do. Therefore, when I asked her if she would do it again, she said she would like more warning (to be fair I did announce my plans to my family at like 8:25pm) so that she could go out a buy a lot more candles! If anybody reading this, tried to last 60 minutes without electricity, it would be interesting to know how you got on
For more pictures of this event taking place around the world see the link to the National Geographic report on it Earth Hour Pictures: Before and After - across the world
I thought it would be quite interesting to see if my family could survive just 1 hour without electricity. So, how did we get on........
Well firstly, I didn't manage to persuade my brother to participate as, for him, the thought of spending an entire 60 minutes without his xbox was unbearable. Instead he decided to part take in the Human Achievement Hour (I am not making this up - it does exist and occurs at the same time as Earth Hour) which encourages people to " Leave your lights on to express your appreciation for the inventions and innovations that make today the best time to be alive and the recognition that future solutions require individual freedom not government coercion". The rest of my family decided to humour me in this challenge, even though they felt it was rather futile as they questionned the impact it would actually have on the global energy consumption (this is true but it kind wasn't the point). So, all the lights and appliances in my house went off, apart from the room my brother occupied, and the first thing I noticed, apart from the darkness, was how quiet everything was (a word of warning, if any of you decide to try this sometime, make sure you light candles before you turn the lights off, as trying to find them, along with matches, and then light them in the pitch black is interesting to say the least!). Unfortunately this peace and quiet didn't last long as my stepdad felt the need to moan about not being able to make a cup of tea literally every 5 minutes. My mum was rather more tolerant than I thought she would be, apart from complaining about the smell of the candles and frequently having to shout at the cat to prevent her from chasing the flickering light of the candles - honestly she was so close to setting herself a light on numerous occasions! I didn't find it too bad but this is partly because I don't really use many appliances and I often get bored of watching TV after 10 minutes. The only thing I hated (and I really did hate this) was the fact that with no lights I was enable to read - reading with a candle it particularly tricky. We therefore sat and had a few lively debates - all revolving around geographical topics and the environment - which I thought was great (although I don't think next time I will be allowed to choose the topics) and they become so lively that our hour was extended to a few as we just lost track of time. However, this was brought to an abrupt end, after my stepdad (gasping with thirst!) may a dash for the kettle - turning on all the lights on the way.
Overall, I didn't find it too bad and I think that I could have gone on longer than 1 hour. I missed the lights the most and I started to realise how restricted people who live without lighting must be - especially those who live near the equator and so experience a very quick transition from daylight to darkness. Did I learn anything from the experience? Well, yes I did. Apart from the fact that animals and candles possibly don't mix, I realised how much technology has killed conversation. It also made me think about the people who complete 8766 Earth Hours a year, as many in the world do not have access to electricity at all. I asked my mum what she thought and she said that she could not believe how much we were reliant on lights and how, despite having candles, we were very restricted to what we could do. Therefore, when I asked her if she would do it again, she said she would like more warning (to be fair I did announce my plans to my family at like 8:25pm) so that she could go out a buy a lot more candles! If anybody reading this, tried to last 60 minutes without electricity, it would be interesting to know how you got on
Friday, 25 March 2011
Earth Hour 2011
A few weeks ago, we had a discussion in class about how different our lifes would be without fossil fuels and I think that we pretty much came to the conclusion that they would be almost unrecognisable compared to the lifestyles that we all currently lead. It is extremely hard to think how, life as we know it, would function without the use of fossil fuels and the transition to this way of life, which is perhaps inevitable, is likely to be a gradual one - well as slow as man kind can force it to be! A life without fossil fuels, at present, maybe practically impossible but do you think you could survive without electricity for just 1 hour of the 8766 that make up a year?
Earth Hour, which is now into its fifth year, has previously involved 128 countries, 89 capitals and 9 out of the world's 10 biggest cities turning off all lights and non-essential appliances for 60 minutes. Earth Hour takes place tomorrow evening between 8:30pm - 9:30pm (local time) across the globe and, although this will not have a significant impact on actual energy consumption or greenhouse gas emissions, it is hoped that it will raise awareness of the many issues surrounding our current energy supply and consumption patterns, whilst being a symbolic show of support against climate change and energy conservation. Here are some pictures, from around the world, of previous Earth Hours...........
Earth Hour, which is now into its fifth year, has previously involved 128 countries, 89 capitals and 9 out of the world's 10 biggest cities turning off all lights and non-essential appliances for 60 minutes. Earth Hour takes place tomorrow evening between 8:30pm - 9:30pm (local time) across the globe and, although this will not have a significant impact on actual energy consumption or greenhouse gas emissions, it is hoped that it will raise awareness of the many issues surrounding our current energy supply and consumption patterns, whilst being a symbolic show of support against climate change and energy conservation. Here are some pictures, from around the world, of previous Earth Hours...........
Tuesday, 22 March 2011
Essays
During last Thursday's lesson we got our essays back that formed part of our half term assignment and, like many of you, I didn't do too badly in the essays. Millie seems to think that it would benefit you, my fellow students, if I posted my essays on my blog so that you can read them. I must admit that at first I was a little hesitant at doing so but on reflection I think that, as well as hopefully helping some of you, it will help me to improve my essay writing as it will enable me to look back on my essays and make a list of things that I need to do to improve them. I must make this point very clear that these essays are not perfect but I did score quite highly in some of them so I must have done something right! I was planning on rewriting parts of them to make improvements (this desire to do so was only furthered after reading the essay that Millie wrote last night which not only dwarfs mine but, to an untrained eye, seems to be extremely good and much better written than mine) but due to a lack of time I haven't been able to do so, so instead I am going to write below each essay the tips for improvements that Millie left (the pink bits) and also my comments on what I would do differently and what I think I did well (the purple bits).
I have written each one in a different post so that you can direct your attention to, perhaps, the area that you didn't score so highly in and so that you don't have to read them all at once. If you have any tips about ways in which you think I could improve my essays they would be much appreciated!
Essay writing, and just English in general, has never been my strongest subject and so I have had to work quite hard, and still am at present, to try and improve my writing technique- especially under pressure and time limits.So, I thought I would share with you some of the tips I have picked up from both workshops and lots of practice.
1. How do I approach the question I face? The first thing I normally do, if I am writing on paper, is to scribble all over the question itself and underline the key points like the command words and what the question actually wants for you. For example, in the first essay in the assignment 'Describe and comment upon the effects and solutions to the Acid rain problem' I would have underlined describe, comment, effects and solutions. The way in which I then appraoched the essay was to describe the effects and then comment on them and then to move on to describing the solutions and commenting on them.
2. Whenever writing essays I try to maintain a similar and simple structure which ensures I do everything that the examiner wishes me to do. I try to include a brief introduction, that presents the issue I am going to discuss, followed by a few paragraphs before finishing off with a conclusion that readdresses the key points I previously mentioned.
3. MENTION CASE STUDIES, even if the question doesn't directly ask you to. According to Nikki, mark schemes often hold back a few marks for the use of case studies as the use of them shows that students really understand the topic and have a wide geographical knowledge.
4. Always try to give both the postive and negative impacts or side effects from the issue/factor metioned, however small and uninfluential they maybe, just remember to weigh up their importance- this is something that I have been trying to include in my essays where possible after I came to the conclusion that geographers seem to concentrate most greatly on one side of the arguement (normally the negatives) without given the other side (normally the positives) a thought. I also think that it can demonstrate that you have really knowledge of the area and have considered the issue from every angle possible. I tried to do this in my acid rain essay and I also did it in an essay I wrote a couple of weeks ago, as part of my revision, on the implications an ageing population has on a countries economy as, although overall the implications are mainly negative, some sectors of the economy may benefit from an ageing population
5. Mention current issues that are in the news. This point is most relevant to the energy essays as the situation is constantly changing and including up to date information surrounding current issues is a great way to show to the examiner that you are a well informed geographer who keeps track of current issues and who also has the ability to link this to the modules despite the fact that the syllabus and exam is written well in advance.
I can also add to these, many of the general things Millie said about my essays which include writing in third person and, without a doubt the most crucial point, writing succintly! Another thing that I haven't mentioned above is how it is sometimes good to try and link your writing to the other modules we have studied as they all interlink in one way or another e.g when writing about energy patterns mentioned development and some of the population stuff is vital in explaining key differences in energy consumption patterns and sources, a long with predicting future energy mixes.
I have written each one in a different post so that you can direct your attention to, perhaps, the area that you didn't score so highly in and so that you don't have to read them all at once. If you have any tips about ways in which you think I could improve my essays they would be much appreciated!
Essay writing, and just English in general, has never been my strongest subject and so I have had to work quite hard, and still am at present, to try and improve my writing technique- especially under pressure and time limits.So, I thought I would share with you some of the tips I have picked up from both workshops and lots of practice.
1. How do I approach the question I face? The first thing I normally do, if I am writing on paper, is to scribble all over the question itself and underline the key points like the command words and what the question actually wants for you. For example, in the first essay in the assignment 'Describe and comment upon the effects and solutions to the Acid rain problem' I would have underlined describe, comment, effects and solutions. The way in which I then appraoched the essay was to describe the effects and then comment on them and then to move on to describing the solutions and commenting on them.
2. Whenever writing essays I try to maintain a similar and simple structure which ensures I do everything that the examiner wishes me to do. I try to include a brief introduction, that presents the issue I am going to discuss, followed by a few paragraphs before finishing off with a conclusion that readdresses the key points I previously mentioned.
3. MENTION CASE STUDIES, even if the question doesn't directly ask you to. According to Nikki, mark schemes often hold back a few marks for the use of case studies as the use of them shows that students really understand the topic and have a wide geographical knowledge.
4. Always try to give both the postive and negative impacts or side effects from the issue/factor metioned, however small and uninfluential they maybe, just remember to weigh up their importance- this is something that I have been trying to include in my essays where possible after I came to the conclusion that geographers seem to concentrate most greatly on one side of the arguement (normally the negatives) without given the other side (normally the positives) a thought. I also think that it can demonstrate that you have really knowledge of the area and have considered the issue from every angle possible. I tried to do this in my acid rain essay and I also did it in an essay I wrote a couple of weeks ago, as part of my revision, on the implications an ageing population has on a countries economy as, although overall the implications are mainly negative, some sectors of the economy may benefit from an ageing population
5. Mention current issues that are in the news. This point is most relevant to the energy essays as the situation is constantly changing and including up to date information surrounding current issues is a great way to show to the examiner that you are a well informed geographer who keeps track of current issues and who also has the ability to link this to the modules despite the fact that the syllabus and exam is written well in advance.
I can also add to these, many of the general things Millie said about my essays which include writing in third person and, without a doubt the most crucial point, writing succintly! Another thing that I haven't mentioned above is how it is sometimes good to try and link your writing to the other modules we have studied as they all interlink in one way or another e.g when writing about energy patterns mentioned development and some of the population stuff is vital in explaining key differences in energy consumption patterns and sources, a long with predicting future energy mixes.
Describe and comment upon the effects and solutions to the Acid Rain problem [15 marks]
The negative impacts that acid rain has on the environment are numerous and this is why many countries have been prompted to adopt policies that reduce the amount of sulphur dioxide, one of the main pollutants that creates acid rain, that they emit in the hope that it will help to reduce the global impacts acid rain has.
Buildings are always going to be effected by weathering but this natural process is accelerated by acid rain. Buildings, especially those constructed from limestone, sandstone or marble, are greatly affected by wet deposition as, for example, limestone dissolves easily in acid rain and a calcium sulphate layer upon the stone is often formed. This layer is easily removed by weathering and leaves even more stone exposed to acid rain. Dry deposition also contributes to the corrosion of materials used in infrastructure. This has an economic impact as it is very costly to maintain ancient monuments as they are very susceptible to damage by acid rain. In the UK, it has been estimated that over the next 30 years savings of up to £9.6 billion could be made if we reduced our sulphur dioxide emissions by 30%. In the future this is not going to be such a big problem as modern infrastructure does not use materials, like sandstone and carbonate rocks, which are particularly vulnerable to acid deposition.
Acid rain has many ecological impacts and perhaps the most significant of these impacts is to aquatic environments. In areas that experience heavy rainfall, the dry deposits are captured in the surface runoff and increase the acidity of the water. Also aluminium is drawn out of the soil and when this combines with the acid it creates a highly toxic environment for the majority of aquatic animals. This combination often results in an increase in fish mortality, a decrease in both fish growth and reproduction and declines in amphibian populations. The effects of this are often felt further up the food chain too as, although birds and mammals are not directly affected by water acidification, changes to the quantity and quality of their food sources greatly affect them.
Vegetation, especially trees, is also affected by acid rain and in a similar way. The aluminium that is drawn from the soil makes it very hard for trees to take up water and the acidic rain itself dissolves the nutrients in the soil and then washes them away before the trees have time to take them in and utilise them. Acid rain damages the leaves and needles on a tree which reduces a trees ability to photosynthesise.
It is clear to see that acid rain has had many negative impacts on the environment but some scientists believe that acid rain has a, small, positive impact in relation to climate change. The bacteria, which lives in wetlands and produces a lot of methane, are very vulnerable to changes in the acidity of water whereas other bacteria, that thrive on the sulphurous conditions, compete with methane producing bacteria. It is believed that this has significantly reduced the amount of methane emitted from wetlands. However, in comparison to the negative impacts acid rain has, this benefit is minimal and, as acid rain is a global problem, many countries have implemented measures to reduce the amount of sulphur dioxide they release into the atmosphere.
By reducing the amount of sulphur dioxide countries emit it has enabled them to reduce the acid rain problem. In 1979 a protocol was introduced which stated that sulphur dioxide emissions had to be reduced by 30% by 1997 and this target was met and furthered as in Europe in the 1990’s emissions were cut by 90%. As well as this, sulphur scrubbers were added to every power station chimney in the UK. In the USA most coal-fired power stations have switched to using low-sulphur coal which can be sourced from areas like Australia and they also have installed sulphur scrubbers to the chimneys. They have also implemented a cap and trade scheme and the combination of these measures have cut America’s sulphur dioxide emissions by over 40% since 1980. The amount of nitrous oxides emitted has not been reduced though and instead have been increased due to an increase in the number of vehicles driven globally and the use of fertilisers. Despite this, at present, the acid rain problem is not as prominent as it was 30-40 years ago due to the success in reducing sulphur emissions. However, unless industrialising countries like China and India are given a cheaper and more available option than coal, the acid rain problem is likely to become a big issue again in the near future. 67% of China’s primary energy consumption comes from coal and coal is responsible for 94% of their sulphur emissions. Acid deposition is already an issue in China with 30% of the country experiencing acid rain provoked problems. As they continue to industrialise, and therefore increase their coal consumption, these figures are likely to rise.
Acid rain has many negative impacts on the environment and attempts to control this problem by reducing the amount of sulphur dioxide developed countries emit has worked to a certain extent. However, these reductions have not managed to solve this issue as it has just moved to different areas of the world that are currently industrializing. If help is not given to developing countries to introduce policies to manage their sulphur dioxide emissions or to find other, greener, cheap and available alternatives to coal then the problems that occurred in the 1970’s due to acid rain are likely to resurface in the near future and on a more destructive scale.
Millie's comments on this essay: She suggested that in my second paragraph I could possibly mention how that although modern buildings, because of the materials used, are less susceptible to damage by acid rain compared to ancient monuments and older buildings which are built from limestone, sandstone, marble and other carbonate rocks; that the manufacturing of more modern building materials is likely to increase industrial emissions and therefore the amount of sulphur dioxide and nitrous oxides released into the atmosphere. Perhaps her most important response to my essay was to suggest that my writing needs to be more succint - unfortunately there is a lot of truth in this. Her concerns surrounding my ability to produce this volume of work in 15 minutes in an exam are also well placed as I realise that there is no way I could ever hope to write this much in an exam. I must admit that it is worrying that I am still struggling, especially as the exam is looming, to write a half decent essay in 15 mintues - tips for writing a minimal amount whilst still managing to get both the depth and breadth required to score highly are desperately needed!
My comments: I don't think that I wrote too badly in the essay and I think that the main issue with it, is that it is not lacking in information and detail but the exact opposite. Although the point that Millie made, in reference to how the manufacturing of modern building materials is going to increase emissions, will be noted I don't think I would necessarily add it to this essay but instead concentrate on cutting out the less important bits and writing more succintly.
There are clearly some improvements that can be made but what do I think I did quite well? Firstly, I think that my structure was better than it has been in previous essays I have written in class as my introduction was short (an achievement for me!) and served its purpose, I described and commented on both the effects and solutions to the acid rain problem whilst managing to make reference to a few case studies and my conclusion was suffient and readdressed the key points I had previously made in the essay.
If you have any tips, points for improvements or good case studies/statistics that I didn't include but perhaps should of then please comment..........
With reference to case studies outline ways in which the fuelwood supply could be managed more sustainably [15 marks]
Theoretically, fuelwood is a sustainable source of energy as trees can be replanted to replace those that are cut down. Reforestation and afforestation schemes are often successful in the countries that implement them but such schemes are often costly and so are only implemented in more developed countries. This means that, globally, the fuelwood supply could be managed more sustainably as it is often the developing countries that rely on fuelwood as a source of energy which often leads to deforestation.
In Nepal, 87% of their primary energy is sourced from fuelwood and the ever increasing demand has led to the destruction of 71% of their forest coverage. This has resulted in the risk of flooding and landslides in both Nepal and neighbouring Bangladesh being greatly increased as the absence of trees increases surface runoff by reducing the interception store and it means that there is a lack of roots to bind the soil. One way to manage the fuelwood supply is to reduce people’s dependency on it by offering other alternatives. In Nepal, to reduce people’s dependency on fuelwood, appropriate technology has been used to give people an alternative to fuelwood. Biogas stoves have been installed in rural areas which run on the methane that is produced when livestock manure decomposes. Not only has this reduced the number of trees that have been cut down but it has health benefits as well as respiratory problems are associated with the smoke produced when fuelwood is burned. The Sahel is another area that has suffered environmental damage due to the unsustainable way in which fuelwood has been gathered. Excessive fuelwood gathering has led to desertification and salinisation and, in an attempt to remedy the problems provoked by deforestation; other alternatives are being introduced to reduce people’s reliance on fuelwood as a source of energy. In the Sahel, solar cookers have been introduced which means that people do not have to rely on fuelwood at all to provide the heat required for cooking. Both of these examples of appropriate technology have reduced the number of trees that are cut down. In developing countries, like Nepal and the African nations, forms of appropriate technology, like solar stoves, are possibly a better and more sustainable way of managing the fuelwood supply than implementing afforestation and reforestation schemes as, by offering an alternative source of energy, people are less reliant on fuelwood. Also many forms of appropriate technology don’t rely on fossil fuels as energy sources which are why they are often very environmentally sustainable.
Another method that could be used to manage fuelwood supplies is to implement afforestation and reforestation schemes. In Europe farmers are given grants, by the European Union, to turn farmland back to forests. However, a similar scheme could only be set up in countries that can afford to offer attractive incentives. A similar method of managing the fuelwood supply has been introduced in Nepal and also involves encouraging the local people to get involved. The aim of the project is to promote the regeneration of the fuelwood supply by encouraging locals to help with the planting of trees which are grown in local nurseries. Such schemes are often very successful as not only do they help to regenerate the forests but also provide locals with the skills required to continue with the replanting of trees in the future. Other countries have also initiated schemes that involve replanting trees and China is an example. China, due to their large population, cut down many of their trees and this has led to the expansion of the Gobi Desert. To prevent further expansion, in 1981, China introduced a law that said that every citizen over the age of 11 has to plant at least one tree every year. As a result of this law, China has the highest afforestation rate in the world and in 2008, 47,000 square kilometres worth of trees were planted. This has helped to solve the deforestation problem but, at present, fuelwood is no longer a major source of energy for China. As China tries to industrialise they have started to use other, more commercial, sources of energy like coal. This shows how finding other alternatives to fuelwood is one approach to managing fuelwood supplies and, in developing countries, this is where forms of appropriate technology that can be used to supply energy are very beneficial for both the local people and the environment.
As fuelwood is, theoretically, a sustainable energy source the easiest way to manage the supply would be to ensure that trees are replanted to replace those that are cut down. In developed countries, that can afford to employ afforestation and reforestation schemes, this has been a successful method however this can work in developing countries too. For example, the replanting tree project in Nepal is a more sustainable way of managing the fuelwood supply as not only does it help to regenerate the forests but it also provides the locals with the skills required to continue this scheme in the future. Another way that the fuelwood supply could be managed more sustainably is by offering some alternatives, like solar cookers, so that people are not totally dependent on fuelwood. Reducing people’s reliance on fuelwood is an important way of managing and preserving the fuelwood supply, as when fuelwood is not the only option the forests are not exploited to the extent that the gathering of fuelwood has a negative and lasting impact on the environment. If measures like these are implemented then fuelwood can be a sustainable energy source for future generations and not have as many negative impacts on the environment compared to those that are created by the current, unsustainable, way of gathering fuelwood.
Millie's comments: Millie felt that I needed to address the issue of the start up costs of implementing afforestation and reforestation schemes in more detail and talk about why this is important, in relation to managing fuelwood supplies. Her biggest criticism of this essay was that it lacked the addressing of how development plays a huge role in determining the management of fuelwood supplies. I failed to mention how,although schemes are great and important, they are not widely implemented due to a lack of both education and funds to kick start them. The fact that developing countries have other priorities, such as securing food, clean water and developing a health and education system, which therefore attract the most funding should also have been mentioned.
A note for Millie incase she reads this: - I found out about the replanting tree scheme, in China, in the second Al Gore book, Our Choice and I can remember that when I first read it, it shocked me slightly and definetly stuck in my mind. This is the extract from the book if you are interested "China stopped deforestation more than 10 years ago, and in 1981, the National People's Congress declared that all citizens of China above the age of 11 (and until age 60) have a duty to plant at least three trees each year. The planting usually takes place in March and April, during spring for most of China. The Chinese tree-planting program is driven by the central government in Beijing, with cooperation from regional leaders. The Chinese people planted 11.7 million acres of forest in 2008 alone - a 22% increase over 2007, according to the statistics released by the Chinese National Greening Committee. Chinese schools require each student to plant at least one tree before graduating, and most schools set aside time for a 'green education, program. The nation announced last year that it will spend almost $9 billion on its tree planting program for the year and set a goal of covering 20% of the nation in forests by next year. The president of China, Hu Jintao, has personally taken part in the tree planting to underscore its importance as a national priority". Apart from this, I am ensure of any other details - especially how a scheme like this is enforced - but I still think it is quite interesting and the statistics released, although I don't know any more recent ones, suggest that it is working.
My comments: This was my lowest scoring essay and I am very tempted, as part of my revision to redo it, especially as I found it the most challenging of the three to start writing about, and include the bits I missed - especially as, on reflection, they are rather crucial points. Levels of development are crucial to consider in practically any essay in relation to the energy module as differences in energy sourcing and consumption patterns ultimately come down to different levels of development and therefore, in this essay, I really should have considered it.
The essay below it just the one we did on the environmental impacts of fuelwood gathering and it was only a 10 mark essay but I thought I would include it anyway as, by realising the impacts of fuelwood gathering, it helpe me to evaluate the steps taken by countries to manage their supplies and the effectiveness of such steps.....
What are the environmental impacts of fuelwood gathering? (10)
Fuelwood is an important source of energy and is heavily utilised in developing countries and even though it is, theoretically, a sustainable source of energy, there are many negative impacts that fuelwood gathering has on the environment – especially if it is not managed. For small, isolated communities fuelwood is normally the most appropriate energy source to utilise and they do not use enough to cause lasting damage to the surrounding environment. However, as the population increases at a rapid rate the number of trees cut down to feed the increasing demand can cause substantial damage to the environment.
87% of Nepal’s domestic energy is sourced from fuelwood and around 71% of the forest coverage has been cut down and this has had many negative impacts on the local environment. In wet climates deforestation reduces the interception store and thereby increases surface runoff which increases the risk of flooding. Deforestation in Nepal, which is situated in the foothills of the Himalayas and so experiences heavy precipitation, has increased the risk of flooding and landslides in neighbouring Bangladesh. The risk of landslides is increased as the absence of trees means that there are no roots to bind the soil. Also the removal of trees means that, during times of flood, there is no large vegetation to prevent the movement of sediment and this increases the impacts flooding has on the local area. Another environmental impact of excessive fuelwood gathering is that it has led to the destruction of animal’s habitats. The forests of Nepal are home to thousands of animals, many of which are endangered or endemic and deforestation, caused by both over-grazing of cattle and the cutting down of trees for fuelwood, has meant that many of these animals have been forced to move or have died.
In regions that have dry climates, like the Sahel, deforestation leads to desertification as a lack of trees means that transpiration doesn’t occur as much and so rainfall happens less frequently. Also there are no roots to bind the soil and, as the soil is more exposed to the elements, it becomes more susceptible to soil erosion. Salinisation often occurs in unison with desertification as the antecedent moisture in the exposed soil is easily evaporated and when this happens the salts in the soil, which are highly toxic to the majority of vegetation, are drawn from the soil and this means that the land becomes even more unproductive than it already was. The combination of both desertification and salinisation has led to prolonged droughts and famines in the Sahel which have been experienced annually since the 1970’s.
Despite the impacts that excessive fuelwood gathering can have on the environment, when it is managed properly and the demand for wood doesn’t exceed the amount of trees that are being replanted, it does have some benefits for the environment. The burning of fuelwood produces a lower quantity of atmospheric pollutants than the combustion of coal and the other fossil fuels. Also the carbon dioxide that it released from the burning of fuelwood is offset by the uptake of carbon dioxide that would have occurred during the trees growth. For people in remote locations, it allows them to have an energy source that they would otherwise be without as they are not connected to a national grid and so can’t access electricity, which they probably wouldn’t be able to afford anyway even if they were connected a national grid. Also, as they can source this energy locally, the pollutants emitted from vehicles, that would have to be used to transport other energy sources like oil or coal, are not emitted.
It is clear that, if the use of fuelwood is not controlled and policies to replace the trees that are cut down are not implemented, the environmental impacts of excessively gathering fuelwood can be disastrous. However, for many developing countries, fuelwood is the only accessible and available energy source for isolated communities and at present, is possibly one of the best alternatives for them to coal, which is the energy source that industrialising countries often turn to next.
“Nuclear energy presents nothing more than a short term fix to the UK’s energy mix problems and the impacts of reaching peak oil” To what extent do you agree with this statement? [15 marks]
More and more money is being invested into nuclear energy and with 10 new nuclear reactors being commisioned, in the UK, in the near future nuclear energy is going to provide an increasing proportion of the energy we both produce and consume.
Personally, I think that; although nuclear energy is a much greener option than using some of the other fossil fuels, it can hold no more than a short term fix to the UK’s energy mix problems as the uranium used is also a finite resource. This means that in the future we are going to have to look for other, more renewable, alternatives to nuclear energy for the generation of electricity as someday the reserves of uranium will also run out. This is one of the main reasons as to why I agree with the above statement as, how can something that is not going to last forever provide a long term fix to problems provoked by our reliance on a dwindling energy source.
Another reason as to why I agree with the statement is that nuclear energy will not be able to remedy all of the problems that will be exposed when we reach peak oil and beyond. Although, using nuclear energy will mean that our electricity generation will be much greener, you cannot simply replace oil with uranium because of the wide range of uses oil has. Oil is used in so many of our everyday items from clothing to modes of transport and plays an important role in food production as it is not only used to power machinery but to make fertilisers, herbicides and pesticides as well. So uranium alone will not be able to fill the gap that will be left when the global oil reserves run out. This is why I think it is important that people recognise that nuclear energy simply cannot be a long term answer to the problems we are going to face and that, although in the short term nuclear energy maybe the best way to go, is it really wise to totally scrap ideas, like the Severn Barrage, to instead give support to projects that aim to develop an energy source that, unlike tidal energy, is not going to exist for ever.
However, in the near future, I think that nuclear energy is going to play a very important role in electricity generation worldwide – especially in the developed countries. The production of nuclear energy has a very low output of greenhouse gases and so, in the short term, is a good alternative for the use of fossil fuels and can be used to reduce our global dependency on oil and coal. Many developed countries, in an attempt to boost their environmental credentials, are likely to turn to nuclear energy as the reserves of fossil fuels run out and more pressure it put on countries to become greener. Also, the supply of uranium is more reliable than the supply of oil as Australia holds the largest proportion (31%) of uranium reserves in the world. Australia is, by far, a much more politically and socially stable country than those in the Middle East who own a large percentage of the world’s oil reserves. Despite how attractive nuclear energy may look to some, I think that we need to remember what is one of the prime causes of the situation we are going to face in the near future and to learn from the mistakes, in terms of our exploitation of energy sources, that have been made. Globally, we are too dependent on oil and so the rate at which reserves are depleting has been accelerated and our reluctancy to invest in alternatives has been escalated. Nuclear energy is becoming an increasingly favourable alternative for many developed countries but it is important that countries to do not become too reliant on nuclear energy as a method of generating electricity as one day uranium reserves will run out.
Overall, I agree with what the statement is saying as how can nuclear energy offer a long term fix to our energy mix problems when, in the future, reserves of uranium will run out. Also, uranium alone, due to the numerous uses of oil, cannot fill the gap that will be left when oil reserves run out. Although I don’t believe that nuclear energy can offer a long term solution to the problems we will face; I think that it will play an important role in electricity generation in the near future. However, I believe it is important that we don’t let history repeat itself and become too dependent on nuclear energy and so I think that, in conjunction with the development of nuclear energy, we should develop our renewable energy sources so that we will not face similar problems in the distant future and so that nuclear energy can be a contributor to the UK’s energy mix in the long term.
Millie's comments: In my second paragraph (why does it seem that I always need to improve my second paragraph?), she said that I needed to define what peak oil is, which seems like an obvious thing to do seeing as the questions refers to it (why can't I do the simple things right!), and also to mention the issue with transport as, in developing countries, oil is primarily used in transport and nuclear power cannot meet this demand. Millie also commented that I need to refrain from posing further questions and, in response, I am going to blame this bad habitat that I have acquired on the writing of this blog as I have got in to the habitat of presented questions when I shouln't - a bit of a bad excuse, I know.
Another point, that will be relevant to any question that asks you to what extent do you agree with this statement, is that I should write in 3rd person but I don't know about any of you, but I find it extremely hard to to say 'I think that.......' or 'I agree.......' in essays like this one. However, this is clearly something that I need to work on.
In the penultimate paragraph, Millie felt that I needed to include the fact that the carbon involved in th construction of nuclear power plants, despite the fact that they have a very low output of greenhouse gases, means that they can never be carbon neutral.
My comments: There are clearly lots of things that could be done to improve this essay but, fortunatley, most of these are things that can easily be included in my future work. I must admit, whilst looking back at this essay, I was impressed at how sort, in comparision to some of the others I have written, it is. However, I still have a long way to go before my work is suffiently succint.
Monday, 21 March 2011
Reassessing the global future of nuclear power
Although my blogging standards have never been that high, they have slipped recently (which is bad I know considering all of the geography related issues that have been in the news) and so I thought I had better start producing some half decent posts over the next few weeks. I haven't had a lot of time tonight and so the three posts I have posted are only brief ones but I am working on some better ones which include questionning whether or not we can go 100% renewable, discussing whether or not current farming practices are renewable and how they are going to have to change in the future, is there such a thing as a man-made natural disaster and some of the controversy surrounding the Lusi mud volcano, amongst others......
Millie seems to have all the news that is going on in Japan pretty well covered and so I thought I would try and take a different approach to the situation and present how the future of nuclear power across the world is currently being reassessed. As the situation involving the nuclear reactors in Japan has continued to escalate the future of nuclear power has become uncertain as the safety of such plants has come under scrutiny and overall, much of the general public are now viewing nuclear power with more hesitance and uncertainity. This reaction was, perhaps, inevitable especailly since many are calling this the worst nuclear accident since the Chernobyl meltdown of 1986 but individual countries have taken a differing approach to the future of nuclear power.
The German Chancellor, Merkel, announced last week that Germany is going to shut down all seven of its nuclear power plants (which produce 23% of the nations energy) that were constructed before 1980 for at least the next three months whilst investigations can be held into their safety. This greatly contradicts what was announced last year in relation to keeping them open into the mid 2030's. Switzerland have suspended all of its nuclear plans pending safety reviews and have also joined an EU initative to stress test all nuclear reactors to determine whether or not they can withstand earthquakes, amognst other emmergencies, with the view that all of those that fail must be permanently closed down. China has also joined Switzerland in suspending its plans for further development of nuclear power until safety reviews have been completed.
Although many other world leaders have called for caution and analysis, many have be much slower at suspending their own nuclear plans. President Putin, of Russia, has said that he will not back away from nuclear power but that “analysis of the current condition of the atomic sector and an analysis of the plans for future development” will occur in the near future. France, who source the majority of their energy from their 58 nuclear reactors, have said, in response to the question presented at the EU's emmergency meeting last week which asked whether or not, in the future, Europe can meet energy needs without nuclear power, that "to say to the French that we are going to give up nuclear power would be lying". India have also refused to rethink their plans to quadruple their nuclear capability by 2020 and claim that the istuation in Japan has only made them, like many other countries it seems, consider "attitional safeguards".
The intentions of increasing the UK's nuclear power generation capability have been made very clear ever since 10 new reactors were commissioned and the situation in Japan has not seemed to greatly affect these intentions as EDF announced yesterday that UK nuclear plants must go ahead. Although many are calling for the government to suspend the approval process for new nuclear sites until the report, commissioned by the government, into the lessons of the Japanese disaster has been published; the boss of EDF has claimed that his company have already reviewed the back-up systems and emmergency plans at all of EDF's existing nuclear plants in the UK. He has also insisted that, although lessons learnt form Japan will be implemented, that the future of nuclear power in the two countries should be considered seperately as the two countries face very different circumstances.
I must admit that I believe that, whether or not you are pro or anti-nuclear, this is the best way to view the situation. I think that lessons can be learnt from Japan, in terms of ensuring that good emmergency plans are put in place, that safety remains of up most importance and that the age of the nuclear reactors is monitered. However, whilst these stress tests are carried out I think that people need to remember that not every country lies in such a tectonically active region as Japan and that the earthquake experienced was extremely large, even for Japanese standards. It is going to be interesting to see just how this industry has been affected after the situation has calmed down a bit and more control over it has been gained. Previous to the nuclear 'crisis' in Japan, I believed that nuclear power would be the energy source exploited by developing countries as they endeavour to boost their environmental credientials and reduce their dependency on oil and coal but this situation has seemed to really shake up the nuclear power industry and put questions on its future. Even the EU has asked whether or not Europe can meet their energy demands without utilising nuclear power or not; although I think that, perhaps, it is rather idealistic to think that Europe can continue to improve its environmental credentials in the near future without using some nuclear power.
There is a really good picture article on National Geographic which individually discusses the problems, if any, that the top 10 nuclear power producers in the world may face due to tectonic activity and how recent events in Japan are likely to change the way they approach nuclear power in the near future. Click on the link below to view it Top Ten Nuclear Nations' Quake Hazard
If any more news, in relation to how the global views and approach to nuclear power have been changed, is announced I will try and update my blog with it as not only is this interesting but it is also very relevant to the energy module we have done and so perhaps could be useful to mention in essays related to the topic.
Millie seems to have all the news that is going on in Japan pretty well covered and so I thought I would try and take a different approach to the situation and present how the future of nuclear power across the world is currently being reassessed. As the situation involving the nuclear reactors in Japan has continued to escalate the future of nuclear power has become uncertain as the safety of such plants has come under scrutiny and overall, much of the general public are now viewing nuclear power with more hesitance and uncertainity. This reaction was, perhaps, inevitable especailly since many are calling this the worst nuclear accident since the Chernobyl meltdown of 1986 but individual countries have taken a differing approach to the future of nuclear power.
The German Chancellor, Merkel, announced last week that Germany is going to shut down all seven of its nuclear power plants (which produce 23% of the nations energy) that were constructed before 1980 for at least the next three months whilst investigations can be held into their safety. This greatly contradicts what was announced last year in relation to keeping them open into the mid 2030's. Switzerland have suspended all of its nuclear plans pending safety reviews and have also joined an EU initative to stress test all nuclear reactors to determine whether or not they can withstand earthquakes, amognst other emmergencies, with the view that all of those that fail must be permanently closed down. China has also joined Switzerland in suspending its plans for further development of nuclear power until safety reviews have been completed.
Although many other world leaders have called for caution and analysis, many have be much slower at suspending their own nuclear plans. President Putin, of Russia, has said that he will not back away from nuclear power but that “analysis of the current condition of the atomic sector and an analysis of the plans for future development” will occur in the near future. France, who source the majority of their energy from their 58 nuclear reactors, have said, in response to the question presented at the EU's emmergency meeting last week which asked whether or not, in the future, Europe can meet energy needs without nuclear power, that "to say to the French that we are going to give up nuclear power would be lying". India have also refused to rethink their plans to quadruple their nuclear capability by 2020 and claim that the istuation in Japan has only made them, like many other countries it seems, consider "attitional safeguards".
The intentions of increasing the UK's nuclear power generation capability have been made very clear ever since 10 new reactors were commissioned and the situation in Japan has not seemed to greatly affect these intentions as EDF announced yesterday that UK nuclear plants must go ahead. Although many are calling for the government to suspend the approval process for new nuclear sites until the report, commissioned by the government, into the lessons of the Japanese disaster has been published; the boss of EDF has claimed that his company have already reviewed the back-up systems and emmergency plans at all of EDF's existing nuclear plants in the UK. He has also insisted that, although lessons learnt form Japan will be implemented, that the future of nuclear power in the two countries should be considered seperately as the two countries face very different circumstances.
I must admit that I believe that, whether or not you are pro or anti-nuclear, this is the best way to view the situation. I think that lessons can be learnt from Japan, in terms of ensuring that good emmergency plans are put in place, that safety remains of up most importance and that the age of the nuclear reactors is monitered. However, whilst these stress tests are carried out I think that people need to remember that not every country lies in such a tectonically active region as Japan and that the earthquake experienced was extremely large, even for Japanese standards. It is going to be interesting to see just how this industry has been affected after the situation has calmed down a bit and more control over it has been gained. Previous to the nuclear 'crisis' in Japan, I believed that nuclear power would be the energy source exploited by developing countries as they endeavour to boost their environmental credientials and reduce their dependency on oil and coal but this situation has seemed to really shake up the nuclear power industry and put questions on its future. Even the EU has asked whether or not Europe can meet their energy demands without utilising nuclear power or not; although I think that, perhaps, it is rather idealistic to think that Europe can continue to improve its environmental credentials in the near future without using some nuclear power.
There is a really good picture article on National Geographic which individually discusses the problems, if any, that the top 10 nuclear power producers in the world may face due to tectonic activity and how recent events in Japan are likely to change the way they approach nuclear power in the near future. Click on the link below to view it Top Ten Nuclear Nations' Quake Hazard
If any more news, in relation to how the global views and approach to nuclear power have been changed, is announced I will try and update my blog with it as not only is this interesting but it is also very relevant to the energy module we have done and so perhaps could be useful to mention in essays related to the topic.
Ice
I am not quite sure what to call this post as it is likely to end up jumping all over the place but seeing as ice should feature in all of the things I am going to try to explain I thought that it would do.
Firstly I am going to discuss albedo. Albedo is a measure of the reflectivity of different objects and surfaces on the earth and the lower the number the more energy that is absorbed, which is believed to contribute to global environmental climate change (or what ever the new term for global warming is). The most reflective surfaces are snow and ice, which have the ability to reflect as much as 90% of the sun's energy back to space. Black carbon (I think it is practically that same as soot) is considered to be one of the largest contributors to climate change, even though unlike all of the other polluntants it is not a gas and it is the shortest lived as once we stop emitting it, it would stop trapping heat in the atmosphere within a couple of weeks. If this is true, then why is black carbon emissions so potentially problematic and what is its link to albedo? Well, black carbon has been closely linked with the acceleration of the melting of ice and snow around the world and thereby a reduction in albedo. The largest source of black carbon is from the burning of biomass which occurs a lot in Brazil, Indonesia, Central Africa and this accompanied with the black carbon produced in Siberia and Eastern Europe by forest fires and the seasonal burning of ground cover has contributed greatly to the progressive disappearance of the Arctic's sea ice cover, as the prevailing winds have carried this polluntant to the Arctic. This is also effecting the Himalayan glaciers. It is believed that 20% of the black carbon in the atmosphere is the result of burning wood, dung and crop residues for household cooking and heating in India. The increasing use of coal-fired power stations in China has added to the black carbon that it produced in this region and, due to the seasonal weather patterns experienced, black carbon poses a particular threat to both India and China. The Indian subcontinent normally experiences 6 months lacking in rain surrounded either side by monsoon seasons and this temperature inversion (a situation where the temperature of the air in the lower troposphere (the lowest layer of the earth's atmosphere) increases with height), which forms over much of South Asia during that period, traps the black carbon above the glaciers and snow of the Himalayas and the Tibetan Plateau. When the black carbon falls on the glaciers, it darkens their surface which causes the snow and ice to absorb the sunlight instead of reflecting it (basically it reduces its albedo) which accelerates the rate of melting. Not only is this likely to present huge issues surrounding water supplies for countries like India, Bangladesh and China who rely on the seasonal melting of the glaciers, for example 70% of the water flowing in the Ganges comes from the melting of ice and snow in the Himalayas, but also that it is reducing the earths natural ability to reflect the sun's energy. The results of a 30 year study of the Northern Hemisphere's albedo was recently published and it suggests that the reduction is albedo due to snow and ice loss is more than double than previously thought. The study involved comparing the model estimates of changes in the Northern Hemisphere's cryosphere (portions of the earth where water is in its solid form e.g sea ice, glaciers, permafrost etc.) with the changes in actual snow, ice and albedo measurements over the same period. The study concluded that, during the 30 year period, cryosphere cooling in the Northern Hemisphere declined by 0.45 watts per square metre and that, on average, for every degree of warming 0.6 fewer watts of solar radiation, per square metre, are reflected to space due to reduced snow and sea ice coverage. The reduction in albedo across the global is increasingly worrying scientists who have seriously considered proposing that all building roofs should be painted white to try and imitate the role that ice and snow play in reflecting solar energy to accompany plans to reduce black carbon emissions. However, as densely populated countries such as India and China continue to develop reductions in the global emissions of black carbon are going to be increasingly hard to meet because the burning of coal and biomass are the largest contributors to the production of black carbon.
I am going to go back to the Himalayan glaciers again but this time in reference to the recent publication of research that suggests that debris on the Himalayan glaciers may be helping to keep them intact. The new research suggests that debris such as rocks and pebbles may help to shield glaciers in the Himalayas from the solar energy and therefore slow the rate at which they are melting. The research that was carried out between 2000 and 2008 on 286 glaciers between the Hindu Kush on the Afghanistan-Pakistan border and Bhutan, disovered that half of the studied glaciers in the northwestern regions of the Himalayas were stable whereas two thirds, elsewhere in the region where in retreat. Retreat rates were also found to be high on the Tibetan Plateau, an area that lacks in debris. The scientists have attributed this difference to the amount of debris present on glaciers and they concluded that debris, in the form of rocks and pebbles, has the opposite effect on glaciers to black carbon and dust. It is hoped that this research could help to explain why glaciers in the Himalaya's haven't all responded in the same way to rising atmospheric temperatures and therefore possibly make it easier for us to predict how glaciers are going to respond to changes in atmospheric temperatures in the future which may enable us to predict the impact that the melting of the Himalayan glaciers will have on the people of China and India.
It is a well known fact that the melting of earth's ice sheets could play havoc with sea levels but to what extent has often be debated. The most recent report (sorry - I realise that this post has involved lots of 'recent reports') by the Intergovernmental Panel on Climate Change suggested that sea levels, before taking into account the Greenland and Antarctic ice sheets, could rise by between 18 and 59 centimetres by 2100. Another report, that did include the ice sheets of Greenland and the Antarctic claim that sea levels woudl rise globally by 56 centimetres by 2100. This prediction was calculated by using NASA satellites to estimate the changes in the ice mass by measuring earth's gravity field over Greenland and Antarctica (the gravity field is apparently affected by changes in ice mass - don't ask me how) and by using monthly measurements of glacier movement and ice thickness. Both reports seemed to produce similar predictions and they also noth agreed that the rate of loss of ice is increasing by 36 gigatonnes a year which is roughly three times as fast as the rate of loss from mountain glaciers and ice caps. However the melting of glaciers and ice caps should not be overlooked as it is estimated that melt from mountain glaciers and ice caps will contribute around 12 centimetres to global sea levels by 2100.
From all of the above I think that it is clear to see that the melting of ice has the potential to have catastrophic human consequences from displacing millions due to rising sea levels and hugely influencing th ewater supply of the most densely populated countries in the world and that little is still known about patterns to glacier melts and why some respond differently to changes in atmospheric temperatures.
Sorry it is all over the place and a bit brief but I hope some of you might have found it vaguely interesting. I am ensure as to whether or not it links to any of the Geography ones or not - perhaps one to do with climate change - but even if it doesn't I think it is quite interesting to see what research is being conducted in terms if ice sheets and glaciers and the effects that human activities have on them.
Firstly I am going to discuss albedo. Albedo is a measure of the reflectivity of different objects and surfaces on the earth and the lower the number the more energy that is absorbed, which is believed to contribute to global environmental climate change (or what ever the new term for global warming is). The most reflective surfaces are snow and ice, which have the ability to reflect as much as 90% of the sun's energy back to space. Black carbon (I think it is practically that same as soot) is considered to be one of the largest contributors to climate change, even though unlike all of the other polluntants it is not a gas and it is the shortest lived as once we stop emitting it, it would stop trapping heat in the atmosphere within a couple of weeks. If this is true, then why is black carbon emissions so potentially problematic and what is its link to albedo? Well, black carbon has been closely linked with the acceleration of the melting of ice and snow around the world and thereby a reduction in albedo. The largest source of black carbon is from the burning of biomass which occurs a lot in Brazil, Indonesia, Central Africa and this accompanied with the black carbon produced in Siberia and Eastern Europe by forest fires and the seasonal burning of ground cover has contributed greatly to the progressive disappearance of the Arctic's sea ice cover, as the prevailing winds have carried this polluntant to the Arctic. This is also effecting the Himalayan glaciers. It is believed that 20% of the black carbon in the atmosphere is the result of burning wood, dung and crop residues for household cooking and heating in India. The increasing use of coal-fired power stations in China has added to the black carbon that it produced in this region and, due to the seasonal weather patterns experienced, black carbon poses a particular threat to both India and China. The Indian subcontinent normally experiences 6 months lacking in rain surrounded either side by monsoon seasons and this temperature inversion (a situation where the temperature of the air in the lower troposphere (the lowest layer of the earth's atmosphere) increases with height), which forms over much of South Asia during that period, traps the black carbon above the glaciers and snow of the Himalayas and the Tibetan Plateau. When the black carbon falls on the glaciers, it darkens their surface which causes the snow and ice to absorb the sunlight instead of reflecting it (basically it reduces its albedo) which accelerates the rate of melting. Not only is this likely to present huge issues surrounding water supplies for countries like India, Bangladesh and China who rely on the seasonal melting of the glaciers, for example 70% of the water flowing in the Ganges comes from the melting of ice and snow in the Himalayas, but also that it is reducing the earths natural ability to reflect the sun's energy. The results of a 30 year study of the Northern Hemisphere's albedo was recently published and it suggests that the reduction is albedo due to snow and ice loss is more than double than previously thought. The study involved comparing the model estimates of changes in the Northern Hemisphere's cryosphere (portions of the earth where water is in its solid form e.g sea ice, glaciers, permafrost etc.) with the changes in actual snow, ice and albedo measurements over the same period. The study concluded that, during the 30 year period, cryosphere cooling in the Northern Hemisphere declined by 0.45 watts per square metre and that, on average, for every degree of warming 0.6 fewer watts of solar radiation, per square metre, are reflected to space due to reduced snow and sea ice coverage. The reduction in albedo across the global is increasingly worrying scientists who have seriously considered proposing that all building roofs should be painted white to try and imitate the role that ice and snow play in reflecting solar energy to accompany plans to reduce black carbon emissions. However, as densely populated countries such as India and China continue to develop reductions in the global emissions of black carbon are going to be increasingly hard to meet because the burning of coal and biomass are the largest contributors to the production of black carbon.
I am going to go back to the Himalayan glaciers again but this time in reference to the recent publication of research that suggests that debris on the Himalayan glaciers may be helping to keep them intact. The new research suggests that debris such as rocks and pebbles may help to shield glaciers in the Himalayas from the solar energy and therefore slow the rate at which they are melting. The research that was carried out between 2000 and 2008 on 286 glaciers between the Hindu Kush on the Afghanistan-Pakistan border and Bhutan, disovered that half of the studied glaciers in the northwestern regions of the Himalayas were stable whereas two thirds, elsewhere in the region where in retreat. Retreat rates were also found to be high on the Tibetan Plateau, an area that lacks in debris. The scientists have attributed this difference to the amount of debris present on glaciers and they concluded that debris, in the form of rocks and pebbles, has the opposite effect on glaciers to black carbon and dust. It is hoped that this research could help to explain why glaciers in the Himalaya's haven't all responded in the same way to rising atmospheric temperatures and therefore possibly make it easier for us to predict how glaciers are going to respond to changes in atmospheric temperatures in the future which may enable us to predict the impact that the melting of the Himalayan glaciers will have on the people of China and India.
It is a well known fact that the melting of earth's ice sheets could play havoc with sea levels but to what extent has often be debated. The most recent report (sorry - I realise that this post has involved lots of 'recent reports') by the Intergovernmental Panel on Climate Change suggested that sea levels, before taking into account the Greenland and Antarctic ice sheets, could rise by between 18 and 59 centimetres by 2100. Another report, that did include the ice sheets of Greenland and the Antarctic claim that sea levels woudl rise globally by 56 centimetres by 2100. This prediction was calculated by using NASA satellites to estimate the changes in the ice mass by measuring earth's gravity field over Greenland and Antarctica (the gravity field is apparently affected by changes in ice mass - don't ask me how) and by using monthly measurements of glacier movement and ice thickness. Both reports seemed to produce similar predictions and they also noth agreed that the rate of loss of ice is increasing by 36 gigatonnes a year which is roughly three times as fast as the rate of loss from mountain glaciers and ice caps. However the melting of glaciers and ice caps should not be overlooked as it is estimated that melt from mountain glaciers and ice caps will contribute around 12 centimetres to global sea levels by 2100.
From all of the above I think that it is clear to see that the melting of ice has the potential to have catastrophic human consequences from displacing millions due to rising sea levels and hugely influencing th ewater supply of the most densely populated countries in the world and that little is still known about patterns to glacier melts and why some respond differently to changes in atmospheric temperatures.
Sorry it is all over the place and a bit brief but I hope some of you might have found it vaguely interesting. I am ensure as to whether or not it links to any of the Geography ones or not - perhaps one to do with climate change - but even if it doesn't I think it is quite interesting to see what research is being conducted in terms if ice sheets and glaciers and the effects that human activities have on them.
Erin Brockovich
Erin Brockovich, which is based on a true story, was my Geography film this week as I thought I would watch a film that presents the environmental and social impacts of the natural gas industry as, when learning about the energy module, we didn't really concentrate that much on the negative impacts on both the environment and people that this industry can create.
The film re-enacts the life of Erin Brockovich, a single mother with no money, no job and no prospects. After her lawyer fails to win her personal injury lawsuit she manages to persuade him to give her a job as compensation for the loss. At first her colleagues fail to take her seriously but this soon changes as she discovers a suspicious cover-up involving contaminated water in a local community which is causing devastating illness amongst its residents.
The groundwater contamination was created when water polluted with hexavalent chromium was stored in ponds that lacked sufficient lining to prevent it from percolating into the groundwater. The Pacific Gas and Electric company was resonsibly for this. The company were transporting natural gas via pipelines that ran throughout the surrounding area. Natural gas has to be re-compressed several times during its transportation and, like many other forms of power plants, large cooling towers were used to cool the compressors. However, the components of the cooling towers are susceptible to corrosion and so hexavalent chromium was added to prevent this from occuring. The water used dissolved the hexavalent chromium and, during storage, it percolated into the groundwater and this not only affected the water supplies in the immediate area as the contamination plume, as it is known, spread.
By studying the medical records of the local people, Erin soon discovered a disturbing link between increased rates of chronic illnesses and the water contamination and after further investigation, including the discovery that the corporate headquarters of PG&E knew that the groundwater was being contaminated and advised Hinkley station to withhold this information for the local people, a judge declared that PG&E had pay large amounts of compensation to all those affected.
So, was this a good Geography film...? The film presents both the negative impacts, which mainly revolve around health, that this industry has had on the local people and the extent to which the large natural gas company are prepared to go to, to cut costs and to cover up the negative impacts of their industry in a very watchable format. Overall, I enjoyed this film and it did enable me to learn a bit more about the negative impacts specific to the natural gas industry. Although I felt that it lacked a bit of depth into the specifics, in terms of the geography related aspects of the films, I would still recommend it as a good film to watch.
The film re-enacts the life of Erin Brockovich, a single mother with no money, no job and no prospects. After her lawyer fails to win her personal injury lawsuit she manages to persuade him to give her a job as compensation for the loss. At first her colleagues fail to take her seriously but this soon changes as she discovers a suspicious cover-up involving contaminated water in a local community which is causing devastating illness amongst its residents.
The groundwater contamination was created when water polluted with hexavalent chromium was stored in ponds that lacked sufficient lining to prevent it from percolating into the groundwater. The Pacific Gas and Electric company was resonsibly for this. The company were transporting natural gas via pipelines that ran throughout the surrounding area. Natural gas has to be re-compressed several times during its transportation and, like many other forms of power plants, large cooling towers were used to cool the compressors. However, the components of the cooling towers are susceptible to corrosion and so hexavalent chromium was added to prevent this from occuring. The water used dissolved the hexavalent chromium and, during storage, it percolated into the groundwater and this not only affected the water supplies in the immediate area as the contamination plume, as it is known, spread.
By studying the medical records of the local people, Erin soon discovered a disturbing link between increased rates of chronic illnesses and the water contamination and after further investigation, including the discovery that the corporate headquarters of PG&E knew that the groundwater was being contaminated and advised Hinkley station to withhold this information for the local people, a judge declared that PG&E had pay large amounts of compensation to all those affected.
So, was this a good Geography film...? The film presents both the negative impacts, which mainly revolve around health, that this industry has had on the local people and the extent to which the large natural gas company are prepared to go to, to cut costs and to cover up the negative impacts of their industry in a very watchable format. Overall, I enjoyed this film and it did enable me to learn a bit more about the negative impacts specific to the natural gas industry. Although I felt that it lacked a bit of depth into the specifics, in terms of the geography related aspects of the films, I would still recommend it as a good film to watch.
Sunday, 13 March 2011
Tides.....
We spent Friday afternoon's lesson learning about tides and how they form and there seemed to be lots of things that we needed to know about them. The extent of my knowledge of tides previous to Friday's lesson stretched as far as the fact that they are created by the moon. So, in an effort to try and consolidate what we got taught, I am going to try and summarise some of the key points....
The tide is the cyclic rise and fall of the ocean surface and it is caused by the moon and the sun exerting force on the earth. This gravitional force has the strength to alter both the depth of the ocean and the oscillating currents. The moon has the greatest influence on tides as it is significantly closer to us than the sun and so water is dragged to the point where the moon is directly ahead. However, the sun also has the gravitational pull to affect tides and this force complicates the lunar tide cycle as the alignment of the moon and the sun influences the amplitude of tides.
The location of the moon, in relation to the sun, determines whether or not we experience Spring Tides or Neap Tides. Spring Tides are the tides with the biggest difference between high and low tides. They occur twice a month (Day 1 and day 14) when the earth, moon and sun are aligned. This alignment puts an extra gravitational pull on the tidal bulge which results in an extra high tide.
Neap Tides are the tides with the smallest difference between high and low tides. Neap Tides occur when the moon and the sun are at right angles to each other (1st quarter = Day 7 and 3rd quarter = Day 21). A smaller tidal range is produced because the lunar high tide coincides with the solar low tide and they partly cancel each other out.
- It takes 28 days for the moon to orbit the earth and it takes roughly twelve and a half hours for a tidal cycle to occur.
- The time between high and low tides when the water is falling is called the ebb and when it is rising it is known as the flow.
- Most places experience two high tides and two low tides a day (semi-diurnal) but some only experience one high and one low tide a day (diurnal).
- Tides do have their benefits which include the fact that they have enabled for the development of ports, maintain the mudflats which migratory birds are dependent on, create currents and transport sediment - these are just some of them and there are plenty more!
- Some areas, like the Mediterranean Sea (experiences a tide of approx 11 inches), do not experience tides and this is because it is not a big enough body of water to feel the gravitational pull of the moon and it is restricted by land.
- However, other areas experience very large tidal ranges. The Bay of Fundy, Canada, has the highest tidal range in the world and one of the main reasons that they experience such high tides is because the water is funnelled through a narrowing channel.
The River Severn has a tidal range which is almost equal to that of the Bay of Fundy and at the time of the highest spring tides, the funnelling effect of the wide estuary, sends a wave several miles up the river against the current. This wave is known as a tidal bore and occurs when the force of the incoming tide is strong enough to force the flow of the river back on itself, thus creating a wave. These tidal bores generally occur around the time of the spring and autumn equinoxes (when the moon is directly above the equator - usually late March abd late September).
The Qiantang River in China experiences possibly the largest tidal bores in the world (9 metres!) and is known locally as the Black Dragon.
Well I think this is the majority of the key points and I actually think that I have managed to consoldiate what I learnt quite well - I hope this will be useful for others of you out there. However, I still have a few questions and I would be very greatful if anyone could shed some light on them .......... so firstly, what determines whether or not an area experiences a semi-diurnal or a diurnal tide? And secondly, if the time between high tides is equal, how come low tides do not occur half way between them?
The tide is the cyclic rise and fall of the ocean surface and it is caused by the moon and the sun exerting force on the earth. This gravitional force has the strength to alter both the depth of the ocean and the oscillating currents. The moon has the greatest influence on tides as it is significantly closer to us than the sun and so water is dragged to the point where the moon is directly ahead. However, the sun also has the gravitational pull to affect tides and this force complicates the lunar tide cycle as the alignment of the moon and the sun influences the amplitude of tides.
The location of the moon, in relation to the sun, determines whether or not we experience Spring Tides or Neap Tides. Spring Tides are the tides with the biggest difference between high and low tides. They occur twice a month (Day 1 and day 14) when the earth, moon and sun are aligned. This alignment puts an extra gravitational pull on the tidal bulge which results in an extra high tide.
Neap Tides are the tides with the smallest difference between high and low tides. Neap Tides occur when the moon and the sun are at right angles to each other (1st quarter = Day 7 and 3rd quarter = Day 21). A smaller tidal range is produced because the lunar high tide coincides with the solar low tide and they partly cancel each other out.
- It takes 28 days for the moon to orbit the earth and it takes roughly twelve and a half hours for a tidal cycle to occur.
- The time between high and low tides when the water is falling is called the ebb and when it is rising it is known as the flow.
- Most places experience two high tides and two low tides a day (semi-diurnal) but some only experience one high and one low tide a day (diurnal).
- Tides do have their benefits which include the fact that they have enabled for the development of ports, maintain the mudflats which migratory birds are dependent on, create currents and transport sediment - these are just some of them and there are plenty more!
- Some areas, like the Mediterranean Sea (experiences a tide of approx 11 inches), do not experience tides and this is because it is not a big enough body of water to feel the gravitational pull of the moon and it is restricted by land.
- However, other areas experience very large tidal ranges. The Bay of Fundy, Canada, has the highest tidal range in the world and one of the main reasons that they experience such high tides is because the water is funnelled through a narrowing channel.
The River Severn has a tidal range which is almost equal to that of the Bay of Fundy and at the time of the highest spring tides, the funnelling effect of the wide estuary, sends a wave several miles up the river against the current. This wave is known as a tidal bore and occurs when the force of the incoming tide is strong enough to force the flow of the river back on itself, thus creating a wave. These tidal bores generally occur around the time of the spring and autumn equinoxes (when the moon is directly above the equator - usually late March abd late September).
The Qiantang River in China experiences possibly the largest tidal bores in the world (9 metres!) and is known locally as the Black Dragon.
Well I think this is the majority of the key points and I actually think that I have managed to consoldiate what I learnt quite well - I hope this will be useful for others of you out there. However, I still have a few questions and I would be very greatful if anyone could shed some light on them .......... so firstly, what determines whether or not an area experiences a semi-diurnal or a diurnal tide? And secondly, if the time between high tides is equal, how come low tides do not occur half way between them?
The Constant Gardener
I fancied a bit of a change from the energy stuff that I have been reading and watching lately and so I decided that, this week, my Geography film would be the Constant Gardener as it presents a totally different branch of Geography from the ones I have been learning about recently.
This film is set in Kenya and follows the lives of Justin, a British diplomat and Tessa, his outspoken activist wife. Tessa spends a lot of her time with a doctor who works in the shanty towns of Kenya and after witnessing people having to be tested for TB whilst wanting to be tested for HIV, she soon starts to discover a secret that many are prepared to kill for to ensure that it remains so. However, despite many trying to control her and prevent her from publicising the fact that a drug corporation are exploiting the Kenyan population for the fraudulent testing of a TB drug that has known harmful side effects and disregards the well-being of its test subjects, she manages to start to gather evidence and write a report which she later sends back to the UK. This report threatens to expose the drug company and the corruption of the government, who knowingly allowed this to happen, and to cost them both millions of pounds and in an attempt to eliminate this threat Tessa ends up getting murdered. Whilst on the hunt for his wife's murderer, Justin too uncovers this conspiracy that, unless he can uncover and publicise its sinister roots, will destroy the lives of millions of innocent people..........
I had previously watched this film but it is an easy one to watch again and, like the first time, I really enjoyed it and it manages to keep your attention through out. It presents some very interesting issues including the fact that, even though drugs are sent to Kenya, they are not fairly and efficiently distributed to the people that are so desperately in need of them. It also touches on the corruption of the many government officials in some developing countries and how some TNC and MNC are, due to the fact that much of the world is dictated by money, prepared to exploit them. The film also portrays the different apsects of life in Kenya from life in the shanty towns to conditions in hospitals and allows for comparisons to be made between rural and urban lives and the difficulties faced by both. Overall, I would highly recommend this film and, even though it does not really link to any of the AS modules, it is definetly well worth watching!
This film is set in Kenya and follows the lives of Justin, a British diplomat and Tessa, his outspoken activist wife. Tessa spends a lot of her time with a doctor who works in the shanty towns of Kenya and after witnessing people having to be tested for TB whilst wanting to be tested for HIV, she soon starts to discover a secret that many are prepared to kill for to ensure that it remains so. However, despite many trying to control her and prevent her from publicising the fact that a drug corporation are exploiting the Kenyan population for the fraudulent testing of a TB drug that has known harmful side effects and disregards the well-being of its test subjects, she manages to start to gather evidence and write a report which she later sends back to the UK. This report threatens to expose the drug company and the corruption of the government, who knowingly allowed this to happen, and to cost them both millions of pounds and in an attempt to eliminate this threat Tessa ends up getting murdered. Whilst on the hunt for his wife's murderer, Justin too uncovers this conspiracy that, unless he can uncover and publicise its sinister roots, will destroy the lives of millions of innocent people..........
I had previously watched this film but it is an easy one to watch again and, like the first time, I really enjoyed it and it manages to keep your attention through out. It presents some very interesting issues including the fact that, even though drugs are sent to Kenya, they are not fairly and efficiently distributed to the people that are so desperately in need of them. It also touches on the corruption of the many government officials in some developing countries and how some TNC and MNC are, due to the fact that much of the world is dictated by money, prepared to exploit them. The film also portrays the different apsects of life in Kenya from life in the shanty towns to conditions in hospitals and allows for comparisons to be made between rural and urban lives and the difficulties faced by both. Overall, I would highly recommend this film and, even though it does not really link to any of the AS modules, it is definetly well worth watching!
Thursday, 10 March 2011
Fire-Tornadoes, Mud Volcanoes and Volcanic Lightning
Today's lesson was, inevitably so, a bit all over the place and so I thought I would take this oppurtunity to write about somethings that have nothing to do with any of the AS modules but that are still quite interesting.
Over a week ago now I read an article about mud volcaonoes and how it has now been predicted that the Lusi mud volcano in Indonesia, which began erupting in May 2006, could continue to erupt for another 26 years. Lusi, which is situated in East Java, is the fastest growing mud volcano in the world and since it began spewing hot mud back in May 2006 it has killed 13 people whilst displacing an estimated 10,000 families. In some areas the thickness of the mud is said to be 18 metres deep and scientists from the UK have said that, over the next 26 years, Lusi could expel the equivalent of 56,000 Olympic swimming pools of mud (that sounds like an awful lot of mud!!!).
Mud volcanoes can appear both on land or under the sea and normally occur when underground layers of silt or clay are pressurized by tectonic activity or a build up of gases. They are most commonly found in areas of high tectonic activity or areas that have large oil and natural gas deposits. Although many mud volcanoes occur naturally, it is believed that they can also be provoked by human activity. For example, it is beileved that commerical drilling provoked a Malaysian mud volcano to start erupting and the eruption of hot mud was enough to claim an entire village.
Recently, a mud volcano starting erupting under the sea off of the coast of Pakistan and has formed a new island - however it is not expected to last long and is estimated that it will be washed away within a few months....
Pakistan is home to quite a few mud volcanoes and they are all created by tectonic activity as the Arabian plate is subducting under the Eurassian landmass. Subduction causes rock to melt into magma and this produces heat and volcanic gases which interact with the groundwater. This causes the groundwater to turn acidic which then dissolves more of the rock above into a mixture of mud and hydrocarbons. This mixture of mud and hydrocarbons are then able to seep through faults. It is rare that mud volcanoes, that are found under the sea, can been seen to be erupting above the surface of the sea as they are not normally large enough to do so.
Lastly on my list of things to quickly talk about tonight is volcano lightning. Not all volcanoes produce lightning but some seem to produce rather a lot, like the 1980 eruption of Mount St. Helens which produced a bolt of lightning roughly every second! Apparently there are two different types of volcanic lightning. The first one occurs within the volcanic smoke and ash plume almost immediately after the volcano has stopped erupting. The process that then causes the lightning is similar to normal lightning (I think) as the ash particles within the expanding eruption cloud become charged. The postively and negatively charged particles then seperate out above the volcano and after a charge has been built up around the volcano, it explodes and sends out a bolt of lightning. I found it quite hard to research the second type of volcanic lightning and I got the impression that not a lot is known about it and so I am just going to try and explain the little bit that I found out about it. This type of lightning occurs during volcanic eruptions, instead of shortly afterwards. When the electrically charged magma, ash and rock leave the volcanic cone it produces a continous sparking at the cone summit - I am then making the assumption that lightning is produced but I couldn't find out any more information after this point. There are some amazing pictures of volcanic lightning - especially from the eruption of the Icelandic volcano, Eyjafjallajokull, last year - so here a just a few of them.....
This is just a brief overview of these three things and I hope that I got most of it right. There are many other examples of mud volcanoes around the world and volcanoes that produce lightning and some of them are quite interesting to read about. One thing, in relation to the mud volcano in Indonesia, that I have been thinking about is, what happens when the volcano stops spewing mud? Will the mud just stay where it is and dry up and then become good fertile land for growing crops or is is going to be too salty or acidic for vegetation to grow on? If anyone knows the answer please comment as I am quite interested to see what the long term impacts of the eruption of this mud volcano are going to be for the local people......
First up is Fire-Tornadoes. I saw an image of a fire-tornado that was seen spinnig over Hungary last week and I must admit that they look pretty cool. I didn't even realise that you could get fire-tornadoes and so I thought I would do a bit of investigation into how they form (sorry, this is another example of how my curosity gets a bit carried away and I may get a little too enthusiastic - hence why I am apologising now!).
Fire-Tornadoes are also known as fire whirls, fire devils and firenadoes and they occur when intense heat and turbulent wind conditions combine and form whirling eddies of air. These eddies often then form a tornado like structure which then picks up burning debris and combustible gases. The structure of a fire tornado consists of a core, a section that is on fire and an invisible pocket of air that feeds the fire. Normally the core of such tornades range from around 0.3 metres to 1 metres wide whilst the height often varies from 15 metres to 30 metres. These fire-tornadoes often occur during wildfires but can also be provoked by earthquakes or natural gas explosions.
Although Fire-Tornadoes normally do not last that long they can be very destructive. The Great Kanto earthquake which occured in Japan in 1923 produced a fire-tornado. Even though this fire-tornado only lasted 15 minutes it is estimated to have killed 38,000 people. However, due to the fact that fire-tornadoes are most commonly formed by wildfires in forests and away from urban areas, normally many do not realise when they occur and they are not often reported. Over a week ago now I read an article about mud volcaonoes and how it has now been predicted that the Lusi mud volcano in Indonesia, which began erupting in May 2006, could continue to erupt for another 26 years. Lusi, which is situated in East Java, is the fastest growing mud volcano in the world and since it began spewing hot mud back in May 2006 it has killed 13 people whilst displacing an estimated 10,000 families. In some areas the thickness of the mud is said to be 18 metres deep and scientists from the UK have said that, over the next 26 years, Lusi could expel the equivalent of 56,000 Olympic swimming pools of mud (that sounds like an awful lot of mud!!!).
Mud volcanoes can appear both on land or under the sea and normally occur when underground layers of silt or clay are pressurized by tectonic activity or a build up of gases. They are most commonly found in areas of high tectonic activity or areas that have large oil and natural gas deposits. Although many mud volcanoes occur naturally, it is believed that they can also be provoked by human activity. For example, it is beileved that commerical drilling provoked a Malaysian mud volcano to start erupting and the eruption of hot mud was enough to claim an entire village.
Recently, a mud volcano starting erupting under the sea off of the coast of Pakistan and has formed a new island - however it is not expected to last long and is estimated that it will be washed away within a few months....
Pakistan is home to quite a few mud volcanoes and they are all created by tectonic activity as the Arabian plate is subducting under the Eurassian landmass. Subduction causes rock to melt into magma and this produces heat and volcanic gases which interact with the groundwater. This causes the groundwater to turn acidic which then dissolves more of the rock above into a mixture of mud and hydrocarbons. This mixture of mud and hydrocarbons are then able to seep through faults. It is rare that mud volcanoes, that are found under the sea, can been seen to be erupting above the surface of the sea as they are not normally large enough to do so.
Lastly on my list of things to quickly talk about tonight is volcano lightning. Not all volcanoes produce lightning but some seem to produce rather a lot, like the 1980 eruption of Mount St. Helens which produced a bolt of lightning roughly every second! Apparently there are two different types of volcanic lightning. The first one occurs within the volcanic smoke and ash plume almost immediately after the volcano has stopped erupting. The process that then causes the lightning is similar to normal lightning (I think) as the ash particles within the expanding eruption cloud become charged. The postively and negatively charged particles then seperate out above the volcano and after a charge has been built up around the volcano, it explodes and sends out a bolt of lightning. I found it quite hard to research the second type of volcanic lightning and I got the impression that not a lot is known about it and so I am just going to try and explain the little bit that I found out about it. This type of lightning occurs during volcanic eruptions, instead of shortly afterwards. When the electrically charged magma, ash and rock leave the volcanic cone it produces a continous sparking at the cone summit - I am then making the assumption that lightning is produced but I couldn't find out any more information after this point. There are some amazing pictures of volcanic lightning - especially from the eruption of the Icelandic volcano, Eyjafjallajokull, last year - so here a just a few of them.....
This is just a brief overview of these three things and I hope that I got most of it right. There are many other examples of mud volcanoes around the world and volcanoes that produce lightning and some of them are quite interesting to read about. One thing, in relation to the mud volcano in Indonesia, that I have been thinking about is, what happens when the volcano stops spewing mud? Will the mud just stay where it is and dry up and then become good fertile land for growing crops or is is going to be too salty or acidic for vegetation to grow on? If anyone knows the answer please comment as I am quite interested to see what the long term impacts of the eruption of this mud volcano are going to be for the local people......
Wednesday, 9 March 2011
Waves - the basics
We have just started our final module of AS Geography - Coastal Environments - and started off by looking at waves and how they form. I have got a feeling that waves are going to be an important part of this module as the characteristic of a wave will determine whether or not erosion or deposition occurs and these processes contribute greatly to the shaping of the coastline.
So, how do waves form? There seemed to be a bit of confusion as to how excatly waves form. Waves are created by the transfer of energy from the wind to the water - not anything to do with the moon! The wind blowing over the surface of the sea creates friction between the two and this causes the water to begin to move in a circular orbit. When the wave reaches shallow waters, friction with the seabed begins to slow the speed at the base of the wave whilst the top of the wave stays the same. This causes the wave to become higher and steeper until it eventually breaks. If you are more of a visual learner the short clip mentioned in the module book is well worth watching - Understanding wave formation . The characteristics of waves differ and waves are often described as either being constructive or destructive......
Constructive Waves: Constructive waves are often created in calmer weather and have less energy than destructive waves. Constructive waves tend to be lower waves with a low frequency but long wave length. As the wave approaches the beach it gets steeper and so when it breaks it gives a gentle spill on to the beach. As the water percolates through the beach material the swash loses energy but remains stronger the backwash. The backwash is often very weak and has insufficient force to pull sediment off the beach. This results in material being slowly, but constantly, moved up the beach which leads to the formation of berms (berms mark the location of the spring high tide)
Destructive waves: Destructive waves are often created in stormy conditions and are a lot more powerful than constructive waves. Destructive waves are high, steep waves with a high frequency but short wave length. As a destructive wave approaches the beach it gets steeper and therefore, when it breaks, it plunges down with quite a bit of force. Due to the fact that there is little swash (forward movement of water up the beach) the backwash becomes dominant and is often very strong. This results is little material being moved up the beach as, instead, it is pulled away. Sometimes destructive waves are known as erosional waves and are often associated with steeper beach profiles. If the force of the wave is great enough it may well project some shingle and other material towards the rear of the beach and this can result in the formation of large ridges known as the storm beach.
Swell Waves: Swell waves are formed by distant storms. These waves travel long distances and are less steep whilst having both a longer wave length (the horizontal difference between successive crests or successive troughs) and wave period (wave period = the time between one crest passing and the next). Swell waves are usually constructive waves.
Sea Waves: Sea waves are formed by local winds and are effectively the opposite to swell waves. Sea waves do not travel very far and whilst being steeper have both a shorter wave length and wave period compared to swell waves. Sea waves are usually destructive waves.
As well as knowing the key characteristcs of waves there also seems quite a few key terms to learn. Most of them seem quite self-explanatory but after I discovered the definition of wave steepness last lesson (the ratio of wave height to wave length) I was quite interested in understanding why this cannot exceed 1:7. So, because I clearly didn't have anything better to do this afternoon and because the prospect of doing a bit of extra Geography seemed so much more interesting than my maths homework, I decided to try and find out why. As waves approach landmasses they get steeper and change shape. This is because the friction that occurs between the seabed and the water causes the circular orbital motion to slow at the base of the wave whilst, at the top of the wave, it continues at its orginial speed. This causes the wave to get steeper as it begins to lean forward. When it reaches the point that its wave steepness is at 1:7 the wave becomes unstable and so collapses on top of itself which forms a breaker. As far as I know, I think that there are two forms of breakers - spilling and plunging. A spilling breaker is a rolling wave that travels gradually up often sloping sandy beaches. The long incline drains that wave of its energy and I am guessing (this is just a gut feeling and so I wouldn't trust me on this) that spilling breakers are therefore most commonly associated with constructive waves as, as the water percolates through the beach material the swash loses energy. A plunging breaker is most commonly found approaching a steeper beach and forms a curling crest, due to the fact that the curling water is travelling faster, which travels over a pocket of air. Again this is a total guess, but I think perhaps plunging breakers are more associated with destructive waves.
Unfortunately I really should get back to my maths homework and so this will have to be it from me tonight - I hope this is useful for some of you. I am going to try really hard over the next few weeks to primilarily write about what I learn in lessons and not get too distracted by other geographical things in the news that interest me - should be interesting to see how long this lasts!!!
So, how do waves form? There seemed to be a bit of confusion as to how excatly waves form. Waves are created by the transfer of energy from the wind to the water - not anything to do with the moon! The wind blowing over the surface of the sea creates friction between the two and this causes the water to begin to move in a circular orbit. When the wave reaches shallow waters, friction with the seabed begins to slow the speed at the base of the wave whilst the top of the wave stays the same. This causes the wave to become higher and steeper until it eventually breaks. If you are more of a visual learner the short clip mentioned in the module book is well worth watching - Understanding wave formation . The characteristics of waves differ and waves are often described as either being constructive or destructive......
Constructive Waves: Constructive waves are often created in calmer weather and have less energy than destructive waves. Constructive waves tend to be lower waves with a low frequency but long wave length. As the wave approaches the beach it gets steeper and so when it breaks it gives a gentle spill on to the beach. As the water percolates through the beach material the swash loses energy but remains stronger the backwash. The backwash is often very weak and has insufficient force to pull sediment off the beach. This results in material being slowly, but constantly, moved up the beach which leads to the formation of berms (berms mark the location of the spring high tide)
Destructive waves: Destructive waves are often created in stormy conditions and are a lot more powerful than constructive waves. Destructive waves are high, steep waves with a high frequency but short wave length. As a destructive wave approaches the beach it gets steeper and therefore, when it breaks, it plunges down with quite a bit of force. Due to the fact that there is little swash (forward movement of water up the beach) the backwash becomes dominant and is often very strong. This results is little material being moved up the beach as, instead, it is pulled away. Sometimes destructive waves are known as erosional waves and are often associated with steeper beach profiles. If the force of the wave is great enough it may well project some shingle and other material towards the rear of the beach and this can result in the formation of large ridges known as the storm beach.
Swell Waves: Swell waves are formed by distant storms. These waves travel long distances and are less steep whilst having both a longer wave length (the horizontal difference between successive crests or successive troughs) and wave period (wave period = the time between one crest passing and the next). Swell waves are usually constructive waves.
Sea Waves: Sea waves are formed by local winds and are effectively the opposite to swell waves. Sea waves do not travel very far and whilst being steeper have both a shorter wave length and wave period compared to swell waves. Sea waves are usually destructive waves.
As well as knowing the key characteristcs of waves there also seems quite a few key terms to learn. Most of them seem quite self-explanatory but after I discovered the definition of wave steepness last lesson (the ratio of wave height to wave length) I was quite interested in understanding why this cannot exceed 1:7. So, because I clearly didn't have anything better to do this afternoon and because the prospect of doing a bit of extra Geography seemed so much more interesting than my maths homework, I decided to try and find out why. As waves approach landmasses they get steeper and change shape. This is because the friction that occurs between the seabed and the water causes the circular orbital motion to slow at the base of the wave whilst, at the top of the wave, it continues at its orginial speed. This causes the wave to get steeper as it begins to lean forward. When it reaches the point that its wave steepness is at 1:7 the wave becomes unstable and so collapses on top of itself which forms a breaker. As far as I know, I think that there are two forms of breakers - spilling and plunging. A spilling breaker is a rolling wave that travels gradually up often sloping sandy beaches. The long incline drains that wave of its energy and I am guessing (this is just a gut feeling and so I wouldn't trust me on this) that spilling breakers are therefore most commonly associated with constructive waves as, as the water percolates through the beach material the swash loses energy. A plunging breaker is most commonly found approaching a steeper beach and forms a curling crest, due to the fact that the curling water is travelling faster, which travels over a pocket of air. Again this is a total guess, but I think perhaps plunging breakers are more associated with destructive waves.
Unfortunately I really should get back to my maths homework and so this will have to be it from me tonight - I hope this is useful for some of you. I am going to try really hard over the next few weeks to primilarily write about what I learn in lessons and not get too distracted by other geographical things in the news that interest me - should be interesting to see how long this lasts!!!
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