Met Office Work Experience - Day 2 (for Tuesday)

My second day at the Met Office and I think I am starting to get used to being here - well what I really mean to say is that didn't get lost!

So, what did I learn today? As to be expected an awful lot - although again much of it went over my head and so I need to go away and do some more reading on some of the areas. First thing this morning I had a really interesting chat to a researcher who is currently running and then analysising the results of various models linked to the changes he estimates will happen to the contiental shelf, temperature and salinity of the oceans, risk of storm surges and sea level in the future. They have been running loads of these simulations in the hope that they will be able to provide a better and more reliable picture of future conditions to several organisations so that they can take the appropriate steps so that they can effectively adapt to the predicted changes. The majority of this session was spent going over the idea of Ensemble modelling anf forecasting (or atleast I think that is what it is called). Over the next few days I will try and explain the basics but first I need to either locate or draw some diagrams etc to help aid the explanation as it will be tricky enough without them. It is actually really interesting as by understanding the basics (and I refer to the real basics as all this modelling stuff soon gets really complex - just trust me on that one!) of the modelling system, you can see how various factors are linked to or provoke a certain reaction and start to understand why there is often much variablility and uncertainity over future projections. Listening to how and why he was doing the research he is doing at present (and I mean like right now - the plots etc he showed be had literally on that morning been completed!) was really interesting and some of the stuff he was looking into really fascinated me. This talk really demonstrated how the some of the work completed help to guide government policy on various topics. I was given a copy of the last MCCIP Annual Report Card which has some interesting regional snapshots of Marine Climate Change Impacts and various impacts, accompained by the risk of them occuring. Here is the link to the summary report which you can read online http://www.mccip.org.uk/media/7562/mccip-report-2010-2011.pdf ; it is quite interesting to read and not that hard to understand as it was written for people and politicians who may not have a great deal of previous knowledge of the topic. We also discussed UKCP90 and went over loads of graphs, plots and data linked to various changes that are likely to occur due to climate change. Again here is the link to their webpage http://ukclimateprojections.defra.gov.uk/content/view/12/689/ and if you click on 'Quick Downloads' you can download the pdf files of the report they produced which I worked through quite a bit of with this researcher. If anyone is doing an EPQ related to climate change they might find the stats, plots, graphs and diagrams included useful to use in their write up or presentation - I may try and sneak a few in!

After this, I attended another seminar but this time on "Climate sensitivity and ocean heat uptake" by Geoff Vallis of Princeton University, USA. I struggled to follow this seminar as, again, it involved lots of models, lots of acronyms I had never come across before, some horribly complicated looking equations and it kind of jumped around a bit. However I got some of the basics of what he was trying to show with his models and equations so I will go for explaining that - like I did with the other seminar. Essentially the overall sensitivity of the climate was discussed, with particular reference to surface temperature, to an increase in greenhouse gas emissions. You probably got this from the title but it focused on the role of the ocean in all of this - remember that the atmosphere and oceans are coupled and they talk to each other (this is what all the scientists at the Met Office refered to the relationship as) and also that the oceans are both a source and sink of gases like carbon dioxide. The main basis of the seminar was on the speed of responses and so say if carbon dioxide instantaneously doubled then an aspect of the climate system would respond rapidly, with a thermal inertia (describes the ability of a given volume of a substance to store internal energy while undergoing a given temperature change, but without undergoing a phase change, so is said to be resistant to temperature change) which is determined by the mixed layer in the oceans.When you then look at long timescales there is a slower element to global warming, one that many consider is effectively irreverisble even if emissions would cease. A fast response, which is commonly classed as the 'transient climate sensitivity' ( I have been picking up some new words and phrases over the last few days!), on the other hand, is only relevant to a response timescale of a decade to century. So basically the seminar was about responses to different factors by the climate and the oceans and the speed of the responses (something which when asked about seemed to divide the conference room in two!). It included links to not only anthropogenic greenhouse gas emissions but also links to volcanic eruptions and ENSO and various other things which he included in his models. The last aspect of this seminar was to look at the model which he referred to as being "embarrasingly simple" and used observational evidence of global warming over the past century to estimate the parameters(although it didn't really look that simple to me - but  the people I was with said that in terms of the equations used and parameters set it was quite simple) and compare it to the results from more complex models and show that the simple model had less uncertainity surrounding it and so is perhaps the better one to use. Over the last few days, one of the many things I have learnt, is that none of these models are perfect - something that was demonstrated in the 'Oceans and Iced Tea' meeting I attended in the afternoon - and that the scientists spend much of their time developing, refining, running and then criticising the models due to the uncertainities that they produce and the errors they sometimes generate. However, these models are crucial as they provide us a insight into the possible future conditions as the variables can be changed and things messed around with a bit to see how different factors provoke different responses. I have got so much I want to write about but I just have to find the time! Hopefully something on modelling (it will be the most simplistic explanation of the basics ever) and on climate sensitivity will appear over the next week.


The afternoon 'Oceans and Iced Tea' meeting was a bit easier to follow (perhaps as my knowledge of terminology on this topic is slightly better) and it was on the topic of erroneous eddies that were appearing on ocean models and why. The reasons discussed including the lack of bathymetry included in the models and the idea of the influence of continental shelves and the shelf currents. Work is always being down to improve the models that they use as they are used to generate data for some may things. Something that surprised me was that many of the models used across the different departments were quite similar and has only small adaptions to make the predictions generated more specific to certain areas.

I also had a rather long chat with some of the summer placement students who are doing like 12 weeks paid work experience at the Met Office where they get to do some proper research using on the models and stuff. These students were all at either the end of their degrees, doing masters or phd's but this scheme is something that I would strongly recommend you keep an eye out for if and when you get to that stage. They all said it was a really great and beneficial thing to do and, in reference to going into this line of work in the future, they all said excatly the same thing - you NEED to have evidence of have done some high level maths or physics from your degree and modelling work!

It was, again, another incredible day and I learnt loads and got a lot of good advice from various different people who definetly gave me a look to think about in terms my future!

Met Office Work Experience - Day 1 (for Monday)

I am an extremely lucky student as for a few days this week I will be at the Met Office in Exeter with the 'Oceans, Cryosphere and Dangerous Climate Change Gourp'; and today (Monday) was my first day! And, because this is such a privilege, I thought I would share with you some of the things I get up to and learn! You will have to bear with me on this thoughh as I can't even pretend to say that I understood everything that I heard about today - the vast majority of it went over my head - and I think my brain is still trying to take it all in!

One of the first things I did today was to sit in on a meeting of the Ocean Biochemistry Working Group whom, like the names suggests, do lots of research into the oceans - whether that be linked to ecocsystems or carbon dioxide uptake or DMS and lots more! Particular focus is placed on the factors affecing carbon dioxide uptake of the oceans and various negative feedback loops that they believe exist involing phytoplankton and temperature control (an idea I will come back to at a later date). This session was really interesting and gave me a really good insight into the work that some of the researchers at the Met Office do. Much of this research is based on calculating the amount of chlorophyll in the oceans and this can be linked to phytoplankton and plankton blooms. Due to its influence on global climate change, the study of such things is crucial in understanding likely future changes in climate. Phytoplankton take in carbon dioxide and is one of the ways in which the oceans take in carbon dioxide as it allows the carbon to sink deep into the oceans where it can be stored. This is an example of a biological carbon dioxide uptake process used by the oceans but there are also physical processes that are responsible for the ocean's uptake of carbon dioxide too. Carbon dioxide dissovles more easily in cold water that in warm water and it also dissolves more easily in sea water compared to pure water because sea water naturally contains carbonate ions (I will spare you from as much of the chemistry as possible at this stage!). The reaction of the carbon dioxide with carbonate produces hydrogen carbonate and because of this reaction, only 0.5% of the inorganic carbon in seawater occurs as carbon dioxide gas. Since levels of carbon dioxide are so low in seawater, more carbon dioxide can enter the oceans from the atmosphere. Something that I never knew before today was that carbon dioxide can be stored in 3 different 'forms' in the oceans and the oceans ability to do this enables it to store more carbon dioxide. Anyway, if the water stays at the surface and warms up as it moves around the globe, the carbon dioxide will relatively quickly escape back to the atmosphere but (this is where I can make a link to my EPQ!) if the water sinks to the deep ocean, the carbon can be stored for more than 1000 years before the general ocean circulation (via the upwelling of the THC after it has completed its circulation of the globe) returns it to the surface. This is one of the reasons that the current circulation pattern is so important as regions in which the sinking of deep water occurs are also, therefore, major physical carbon dioxide removal areas - especially the North Atlantic.

After a tour of the building (which is massive and very modern!) I attended a seminar on "The sensitivity of the energy and water cycles to different forcing agents" by Nathalie Schaller from the Institute for Atmospheric and Climate Science, ETH Zurich, Switzerland. I will try and talk about some of the background of this seminar as the majority of it discussed various models - something that went way over my head! It is now commonly accepted that, as a result of anthropogenic influences, primarily greenhouse gas emissions, that the hyrdological cycle, on a whole, will be intensified which, in turn, will have major impacts on human soieties and ecosystems. Therefore it is vital that more reliable statements about future changes to precipitation patterns can be found and this is where various global climate models come in. The variabilty produced by various models leads to some uncertainities which are then only amplified by the added complications of forcing agents such as solar forcing and carbon dioxide. So, basically, this seminar consisted of the results of running various simulations with different forcing factors, at varying levels and over varying temporal and spatial scales, to see what the likely impacts are. I think that one of the main messages was that the relationship between the energy and hydrological cycles with the forcing factors, especially CO2, was not linear and so say increasing the forcing agent by x2 wouldnt just lead to twice the impact on the hyrdological cycle and in many cases it is more. Despite the content being far to advanced for me to even start to really get an substantial understanding of it, it was really interesting to see some of the worrk happening in various research departments around the world and, if I manage to do a bit of reading over the next few days, I may write a post on the alterations that the discussed factors could make to the movement pattern of the ITCZ and the global impacts of this as this was something briefly touched upon.

Then, to finish off a great day, I had a discussion with a researcher about ocean circulation. Lots was covered, which I won't go into too much now but I am hoping to be allowed to include some of it in my EPQ. Something I think I will briefly discuss is the idea of vorticity as it is important in explaining the differing characteristics of eastern and western boundary currents and the formations of gyres - I might elaborate on it at a later date (perhaps including some maths!). Energy and mass are not the only properties that must be conserved as momentum also has to be - both in terms of linear momentum (associated with motion in straight lines) and angular momentum ( associated with rotatory motion). Vorticity essentailly means the 'tendency to rotate' and it is referred to as 'tendency' rather than simply 'rotatory motion' as water can be aquiring both positive and negative vorticity at the same time. Therefore, instead of saying the conservation of angular momentum or tendency to rotate, it is referred to as the conservation of vorticity. Ocean water have rotating movements on all scales - from large basin wide subtropical and subpolar gyres to tiny eddies. For water to have vorticity, therefore the tendency to rotate, it doesn't have to been enclosed in a closed system as, as long as there is a current shear (a change in velocity at right angles to the direction of flow), rotatory motion will be possible. Mainly due to the fact that it apparently makes the maths easier, a tendency to rotate anti-clockiwise is referred to as positive and a tendency to rotate clockwise is referred to as negative. I mention a before about that fact that water could aquire both positive and negative vorticity and the first time I heard this I was a little confused but an example I was given helped me to understand it a little better. So, water could be aquiring positive vorticity as a result of current shear provoked by friction with an adjacent water body or coastal feature (say a spit), whilst also aquiring negative vorticity from a wind blowing clockwise. Therefore the actually motion will depend on the relative sizes of the two tendencies and so, in theory, no rotational motion could be the result as the tendencies could be equal. This rotatory motion is caused by wind stress and so is said to be relative vorticity but, as with anything linked to ocean cicrulation, the rotation of the Earth complicates things and so the vorticity possessed by a parcel of fluid on the rotating Earth actually has planetary vorticity - this is where the Coriolis force links in. When I have talked about Coriolis force before, I have explained it in terms of the poleward decrease in the eastward velocity of the surface of the Earth. However, although this is okay for the basics, there is something missing........... In addition to this linear eastward velocity, the surface of the earth also has an angular velocity which means that, in the Northern Hemisphere, it turns anticlockwise about a local vertical axis (southern hemipshere is opposite). This angular velocity os latitude dependent and so there would be a relative motion between the moving parcel regardless of the direction it was initially travelling in; with this relative motion increasing with increasing latitude (this applies to both winds and currents). This is where a lot of maths comes in but I will try and skip over most of it as I am struggling to get my head around all of it! Linear eastward velocity decreases with latitude whereas the angular velocity about a local vertical axis increases latitude. The bigger the angle between the Earth's axis of rotation and the local vertical axis, the smaller the angular velocity of the surface of the Earth about this local vertical axis and so, at the Equator, where a vertical axis is perpendicular to the axis of rotation, the angular velocity is zero. So, I guess what I am trying to say is that any parcel of fluid on the Earth shares the components of the Earth's angular rotation, appropriate to that latitude. I hope you kind of followed that - if you did it would be really good to know as then maybe I can include it in my EPQ! It is quite a tricky area and I am still trying to fully understand it and I haven't even got into much of the maths yet! I will come back to this idea soon though as when you combine it with a summary of Stommel's (he is this guy who has done loads of thereotical stuff on the basics of ocean circulation) calculations, it helps to explain the characteristics of different boundary currents - which is both relevant to my EPQ and I find it quite interesting!

Sorry for not going into much detail about these things but I still need to do a bit more further reading and perhaps some images to aid my explanation and my brain is rather tired and I need a good nights sleep! Honestly, I don't think I slept at all last night as I was like a little kid on Christmas Eve - but to be honest who can blame me as, being an aspiring Geographer, I really couldn't of asked for much more as a kind of early Christmas present really! Anyway, I will come back to these various topics at some poitn soon and write something that is more beneficial for you all to read...................

I have another extremely interesting day to look forward to tomorrow with another meeting, seminar and some more discussion groups and so, if I manage to contain my excitement, my blog post will hopefully make more sense and be a bit more logical!

Sorry that this is a bit late in arriving, I couldn't seem to get the post to publish over the last few days so its kind of all out of time but better late than never I suppose!

The basics of ocean circulation - my rather rough first draft of section 1

This is my rather rough first draft of the first section of my EPQ. I realise that the phrasing is a bit clumsy in places and that, on a whole, it needs a lot of refinement and a great deal of condensing (I am currently in the process of doing this)! However I have a bit of a favour to ask; I have struggled to gauge how much scientific/academic content I can include and so what would be really useful to know is whether or not you understand it all? Are there any bits that are perhaps a bit too heavy? Anything that needs further explanation? Is there anything that is a bit to simple and you don't feel needs to be explained? Or do you want more scientific/academic content?!? Any feedback would be greatly appreciated! By the way, ignore all the little numbers, they are my footnotes and I didn't feel that you needed all my reference stuff! I hope your EPQ's are going well!

The circulation of the oceans can be defined as the “average movement of seawater, which, like the atmosphere follows a specific pattern” [1] and the general purpose of ocean circulation is to exchange waters of differing properties, principally temperature, salinity and density, throughout the interrelated and interdependent network of oceans that cover approximately 70.8%[2] of the world. In simplistic terms, the ocean circulation comprises of horizontal movements, known as currents and vertical movements, designated upwellings or downwellings.  

The disharmonious characteristics of water masses in the oceans are crucial to the oceanic stratification that divides the currents and allows for limited mixing only. This naturally occurring phenomenon is vital to not only the structure of the general ocean circulation but also the productivity of the oceans. Vertical stratification is provoked by the, sometimes only subtle, differences in density. Water density is regulated by temperature and salinity (with overlap between the two existing); where cold, salty water being the densest sinks and warm water, with a low salt content, thus more buoyant, floats upon the denser water.  The thermocline, the region in which the rate of decrease in temperature with increase in depth is the largest, forms a boundary between warm and cold currents across which water is prohibited from passively mixing and the halocline (the vertical zone in the oceanic water column within which salinity alters most rapidly with depth) essentially does the same, although linked to salinity. The depth of the thermocline, as with the halocline, varies seasonally, especially in mid-latitudes where an additional shallower thermocline often develops in the summer or in high latitudes where the thermocline may only become visible seasonally. The variations can extend over a larger temporal scale, especially in the Pacific, as the thermocline plays a fundamental role during ENSO. As the pycnocline is the area where density increases most abruptly with depth; both the thermocline and halocline can closely be associated with it and in fact substantial overlap between all three ‘layers’, which separate the mixed-layer from the deep ocean, exists. The idea of the close relationship between the thermocline, halocline and pycnocline is intrinsic to the stability of ocean stratification as a decrease in temperature harvests an increase in density and thus a stable stratification but a decrease in salinity provokes a decrease in density and thereby an unstable stratification. However, because the influence of temperature overrides that of salinity; the general stratification is stable. Although stable stratification represses passive mixing, due to the wind, upwellings, downwellings and storms, turbulent mixing does occur to varying extents. As this mixing allows for nutrients to be pushed to the surface and oxygen to the deeper layers, it is crucial for the productivity of oceans. Therefore the stratification is important but continual and intensified stratification can have a detrimental effect on ecosystems as, an increase in sea temperatures provokes an increase in strength of the thermocline boundary, thereby placing greater restraint on the movement on nutrient rich waters due to the further suppression placed on turbulent mixing; hence why during El Nino Peruvian fishermen suffer greatly as the fish move to the colder, deeper waters which have a higher oxygen and nutrient content.

Ocean currents are large-scale movements of water within oceans that are a critical mechanism in the Earth’s heat transfer system which conveys heat from areas of surplus to areas of deficit. There are essentially two varieties of currents: cold ocean currents which flow along the ocean floor from high latitudes to the tropical regions and warm currents that migrate polewards from the Equator, with close proximity to the surface.

Gravity, in relation to Sir Isaac Newton’s equation of motion[3], obviously has an effect on ocean currents, and their formation, within the general circulation, but pressure-gradient forces and frictional forces also play an influential role in their formation and motion. Hydrostatic pressure is important to the formation of currents as the Earth is not flat and completely evenly covered in water. Landmasses interact with currents firstly because land has different thermal properties to oceans[4] and secondly as landmasses form boundaries along which water tends to ‘pile up’, thereby creating a sloping horizontal sea surface, upon which the hydrostatic pressure will act on accordingly, depending on depth. In essence this generates horizontal pressure gradients and so, in the same way in which heat transfers from areas of surplus to deficit, water tends to flow so as to balance the lateral differences in pressure[5]. As the oceans are not homogeneous, the horizontal differences in density (as a result of fluctuations in temperature and salinity) provoke the hydrostatic pressure to vary along a geopotential surface and with depth thus favouring baroclinic conditions (where isobaric and isopycnic surfaces are inclined in relation to one another and isobaric surfaces follow the sea-surface less and less with increasing depth). It is the baroclinic conditions that are responsible for currents that vary with depth. Barotropic conditions (where isobaric surfaces are parallel to both sea-surface and isopycnic surfaces) form in well-mixed areas or below the permanent thermocline and so, to some extent, characterise the deep ocean.  Although vertical pressure gradients are greater than horizontal pressure gradients, the latter are a significant contributor to the occurrence of ocean currents. When the horizontal pressure gradient force is balanced by the Coriolis force, geostrophic currents are produced. The balance that allows for their occurrence dictates that the current direction has to be perpendicular to the horizontal pressure gradient as Coriolis always acts perpendicular to the motion. This results in high pressure always being situated to the right in the Northern Hemisphere and left in the Southern Hemisphere, in relation to the current direction.

The ocean circulation derives its energy initially from the Sun as, due to the fact that the intensity of insolation varies between the Equator and the Poles, a temperature gradient is generated which instigates the transfer of heat, in both the atmosphere and the oceans, to move from areas of surplus to deficit. Therefore it is this temperature gradient that essentially triggers the ocean circulation. The atmospheric and oceanic circulations are very closely coupled, principally due to the heat exchange that occurs between them, and so they play a dictatorial role in determining the general circulation patterns that occur. Basically, it is the Sun that drives all the ocean currents, although most directly the surface currents (found in the upper 100 metres of the ocean[6]), via either the prevailing winds generating friction with surface waters or temperature variations inducing density gradients.

When wind blows over the ocean, not all of the energy that is transferred is expended in the generation of surface gravity waves; some is used to drive currents and the pattern of these wind-driven currents is similar across all of the oceans. The prevailing winds drag on the sea-surface, provoking it to move and build up in the same direction as the wind is blowing. This effect of wind stress on the sea-surface is transmitted downwards as a result of internal friction within the upper ocean and starts to build up momentum and drive the currents. In general, the wind-driven circulation attenuates with depth but the exact penetration depth of the wind-driven circulation is regulated by the strength of water column stratification. Regions of strong stratification, like the tropics, will include surface currents that reach a maximum depth of 1000 metres[7], whereas in the poles, where stratification is low, these currents can extend to the sea floor. The reasoning behind why stratification is important in the extent to which wind-stress affects ocean currents is linked to the idea of eddy viscosity and its magnitude as the turbulent eddies, located in the upper layer, “act as a ‘gearing’ mechanism”[8] for translating motion from the surface to layers below.  

Winds are not always constant in strength or direction and so when a wind that has been driving a current ceases to provide sufficient energy to do so, inertia currents are created. Momentum will not leave the water immediately as, in open ocean, it takes a while to dissipate and whilst in motion, frictional forces and Coriolis force will continue to act upon them, thus resulting in a circular motion that characterises inertia currents. The extent of this circular motion is determined by the influence of Coriolis over other forces with the most circular inertia currents being generated when Coriolis is the only horizontally acting force on a current whose journey involves minimal latitudinal movement. The energy in the oceans is both kinetic, by virtue of its motion, and potential due to the displacement of isopycnic and isobaric surfaces and it is this huge store of potential energy in the oceans that ensures that the ocean circulation would take a few decades to completely cease if global winds stopped blowing.

The Coriolis force is a substantial dictating factor determining the direction of ocean currents and this effect is generated by the anti-clockwise rotation of the Earth; without the influence of the weak frictional coupling between moving water and the Earth surface[9]. If the Earth didn’t rotate then both the atmospheric and oceanic circulation would circulate to and from the polar regions (high pressure) to the Equator (low pressure) in a continual motion[10]. However, the incessant eastward rotation of the Earth causes a more complex pattern of movement. The circumference of the Earth is greatest along the Equator and so the eastward motion of the Earth’s surface is greatest here; whereas at the poles, where circumference is at is minimum, the velocity is zero. Therefore, if a volume of fluid (or any moving particle) flows north from the Equator; it will sustain its constant eastward momentum but, as it gets within a forever closer proximity to the Poles, the Earth beneath it will gradually slow, thereby provoking the water mass to move to the right, in relation to the Earth. Its general effect on currents is to cause then to turn to the right (east) as they progress north from the Equator and to the left (west) as they migrate south from the Equator. This is the Coriolis Effect and its strength increases as the water (or wind) moves further away from the Equator and thus, the distance that the currents flow away from the Equator governs how far, to the left or the right, they ‘bend’.  This stimulates the production of gyres – large circular flows that flow clockwise in the Northern Hemisphere and anti-clockwise in the Southern Hemisphere – that flow around all of the major ocean expanses and divide the wind-driven circulation[11]. There are two types of gyres: subtropical gyres that extend from the equatorial current to the maximum westerlies (lies at latitude 50°) and subpolar gyres, which are cyclonic circulation features that extend polewards of the maximum westerlies and within which Ekman transport forces surface water divergence and upwellings. Subtropical gyres are anti-cyclonic circulation features where convergence occurs due to Ekman transport within them provoking downwellings. The central point of subtropical gyres is shifted to the west, thus intensifying the westward ocean currents, due to the strengthening of the horizontal Coriolis force with latitude (Stommel 1948)[12]. This produces faster flowing, western boundary currents that are warm but narrow. Winds that circulate around the subtropical gyre push cooler currents, which are slower moving broad but shallow eastern boundary currents[13], towards the Equator, affecting the western side of continents.

The Coriolis Effect also influences the Ekman layer (wind-driven layer) in other ways. As explained previously, wind exerts stress on the sea-surface proportional to the square of wind speed in the direction of the wind, thus initiating momentum in the surface water. It was Ekman that calculated that the influence of wind-stress attenuates exponentially with depth and therefore so does the velocity of the effected currents. However, the Coriolis force stays constant with varying depth, thereby provoking, in theory, the formation of an Ekman Spiral. This spiral current pattern is important but Ekman’s most significant theory was the fact that “the mean motion of the wind-driven layer is at right angles to the wind direction”[14] (to the right in the Northern Hemisphere and left in the Southern Hemisphere) and the volume transport in this direction, often referred to as Ekman transport, moves water in response to prevailing wind fields, therefore contributing greatly to the general circulation. Ekman transport that is wind-induced gives way to Sverdrup transport (Sverdrup 1947)[15] which produces the ocean current pattern. Ekman transport varies across the oceans and contributes to the generation of divergence and convergence. Ekman convergence forces downwellings that accumulate less dense surface water and forces it to sink whilst divergence leads to upwellings which replaces the less dense surface water with dense water drawn up from below. Variations in Ekman transport can be reflected in variations in sea-surface level and under divergence the sea-surface is lowered whilst the thermocline is raised; with this upward movement of water being known as Ekman Pumping; therefore also meaning that Ekman transport can have an impact on the horizontal pressure gradient force.

Landmasses, especially large continents, modify the pattern of ocean circulation. The Earth is not symmetrical and the Southern Hemisphere, of which only 19%[16] is land, contains most of the world’s oceans. As land heats up faster than water, the landmasses of the Northern Hemisphere make their surrounding seas warmer than those of the Southern Hemisphere – a factor that influences water density. Especially in relation to the thermohaline circulation, the presence and distribution of mountains in relation to prevailing winds has an impact due to their influence on the extent and location of evaporation and precipitation.  Also, the landmasses cause significant modification to the direction of both atmospheric and oceanic currents as they force masses to ‘pile-up’ along the boundaries they form. Seafloor topography also plays a role in determining the direction of movement as the shape of ocean basins impacts both surface and deep water currents by restricting the areas where water can move and funnel it into another.

The Gulf Stream is one of the strongest western boundary ocean currents in the world and is driven by surface wind-stress. It is only one of many currents that construct the oceanic circulation but, with reference to its impact on the UK, is one of the most influential. It is paired with the eastern boundary Canary current and flanks the North Atlantic gyre. The waters feeding into the Gulf Stream begin flowing off the west coast of Northern Africa where this water is moved across the Atlantic Ocean by the Atlantic North Equatorial Current that flows from African, across the Atlantic. When this current reaches the eastern side of South America it splits into two currents. One of these currents is the Antilles current, which is a branch of the Atlantic North Equatorial Current, and forms part of the clockwise-setting ocean current system in the North Atlantic. The Antilles current flows along the north side of the Greater Antilles Islands before merging with the Florida current, which emerges from the Gulf of Mexico through the Straits of Florida to form the initial portion of the Gulf Stream. The other branch of the original current is funnelled through the Caribbean Islands and the Yucatan Channel where, because it is narrow, it is able to compress and thus gather strength. As the strengthened current enters the warm waters of the Gulf of Mexico is start to circulate, gaining further strength, before exiting, via the Straits of Florida, and re-joining the Antilles current. The characteristics of the Gulf Stream at this point, in relation to temperature and salinity, represent the fact that it has been supplemented by waters from both the Antilles current as water that has recirculated in the Sargasso Sea. The Gulf Stream becomes visible on satellite images in the Gulf of Mexico and is therefore said to originate here. After exiting via the Straits of Florida, the Gulf Stream flows parallel to the east coast of the USA until it reaches the open ocean at the Cape of Hatteras where it then proceeds to move north. Between the Straits of Florida and Cape Hatteras, the current flows along the Blake Plateau, following the continental slope. This keeps the current well defined, very narrow and limits it to a depth of about 800m[17]. Beyond Cape Hatteras it moves into deeper water (4000-5000m)[18] because it has left the continental slope and any topographic constraints. This means that the current can now meander, which is exactly what it does, and it is these meanders that give rise to the Gulf Stream ‘rings; or eddies. As the Gulf Stream moves towards the Grand Banks off Newfoundland it broadens and starts to be referred to as the North Atlantic current. At this point the current branches off into two directions: some turns south-eastward to contribute to the Canary current where it recirculates in the subtropical gyre whilst the rest progresses north-eastward between the UK and Iceland where it joins the subpolar gyre.

Initially the Gulf Stream is considered to be a wind-driven current but, because during winter it is forced to sink at subpolar latitudes, thus forming dense deep water which flows equatorwards and contributing to the deep recirculatory flow, whilst also provoking more of the Gulf Stream polewards to replace that forced to sink; it is also considered to be driven by the thermohaline circulation. 

Not all parts of the ocean circulation pattern are driven by wind-stress. Deep water currents are driven by the thermohaline circulation, which is initiated by density differences, and are found below 400m[19] where they make up approximately 90%[20] of the ocean. Although gravity, frictional forces and Coriolis force also affect the deep water currents, it is the density differences that are the real driving forces behind them.

This deep circulation is caused by density changes in oceanic water resulting from changes in temperature and salinity, hence its name ‘thermohaline circulation’, which are caused by cold winds cooling surface waters, the input of freshwater from either precipitation or melting ice, the cooling and freezing of seawater into sea ice or the evaporation of sea water. The basic thermohaline circulation is initiated when denser water (predominately the cooler, saltier water) sinks below the more buoyant water (warm, with a low salt content). Convection penetrates to a level where the density of the sinking water matches that of the surrounding water. When this maximum penetration level has been reached, it will gradually spread into the rest of the ocean. Once the dense water masses have spread into the full extent of the ocean, they will slowly upwell to supply the slow return flow to the sinking regions and replace the surface waters lost.

The fluctuations in density are responsible for the formation of intermediate, deep and bottom water masses, all of which are crucial to the idea of the Global Conveyor Belt. Intermediate waters are defined as being relatively dense and therefore sink part of the way. Deep water is very dense so sinks and navigates along the ocean floor and bottom waters which are the very densest water (overlap between deep and bottom water exists). The depth that the water sinks to is determined by its density and that of the surrounding water masses as each water mass sinks from the surface until it reaches a depth where it has less dense water on top and denser water below[21].

This thermohaline circulation is best developed in the Atlantic due to high evaporative enrichment of salt which produces a high salinity. However, it cannot be initiated in other oceans as conditions prohibit the crucial sinking of the denser water. For example, the Pacific sea-surface waters have too low a salt content to allow for sinking into the interior and the Indian Oceans are too warm for sinking to occur.

The Gulf Stream transports warm, salty water to the north-east of the Atlantic where this warm water cools and mixes with the cold water originating from the Arctic Ocean. This causes it to become dense enough to sink, both to the south and east of Greenland. The resulting current is part of a larger system that connects the North Atlantic to the rest of the Atlantic, the Indian and Pacific Ocean and the Southern Ocean, where the two main sinking regions spread out in the subsurface ocean where it is able to affect all the world’s oceans from depths of 1000m[22] and below.  The cold, dense water gradually warms and returns to the surface, throughout the world’s oceans. The surface and subsurface currents, the sinking regions, and the return of the water to the surface form a closed loop, commonly referred to as the global thermohaline conveyor belt. This conveyor belt starts in the Atlantic where the salty upper Atlantic water proceeds northwards to the vicinity of Iceland. Here it is cooled and thus thermally densified, allowing it to sink through the interior before it flows south where it forms the conveyors lower limb. It passes the tip of Africa before joining the Southern Ocean Runway, which transports this dense water around the Antarctic continent. Whilst flowing around Antarctica, mixing with the brine-densified winter runoff waters from the surrounding ice shelves occurs. The resulting denser water then goes on to enter both the Pacific and Indian Oceans as bottom water which forms the lower limbs of the anti-conveyor circulation. Branches of intermediate water, which is formed along the northern boundary of the Southern Ocean, infiltrates into all the three main oceans before further horizontal mixing occurs, deep into the  oceans.

There are many important deep water formations that have great influence on many factors that affect our lives but explaining them all is beyond the scope of this project; instead focus is going to be placed on the North Atlantic Deep Water (NADW). NADW is initially formed in Greenland and the Norwegian seas due to salty water introduced by the cold Norwegian current and the increase in salinity, as a result of sea ice formation which causes the NADW to descend with close proximity to Iceland where it is further densified by both additional evaporation of the waters within the NADW and subtropical brines. The NADW extends southwards, in the form of a convective plume, from its formation site in high latitudes and therefore has to be replaced by a northwards counterflow of surface water. This is where a link between the Gulf Stream and NADW is developed as the deep-water movement amplifies the Gulf Stream flow; therefore making the two currents interdependent. Further deep water is added by both the Labrador seas, via the convective feature known as chimneys, and as a result of the net evaporation that occurs in the Mediterranean Sea. This incredibly salty water soon ventilates the Atlantic Ocean and spreads rapidly away from its source. Upon reaching the Antarctic Circumpolar current, it spreads into the Indian and Pacific Oceans. The sinking of the NADW is counter-acted by an upwelling in the Southern Ocean as the NADW exported to the other oceans must be balanced by an inflow of upper-layer water into the Atlantic. Some of this water returns in the form of the Antarctic Intermediate Water whilst the rest returns as warm salty thermocline water from the Indian Ocean. At this point, the remainder of the NADW combines with the water in the Southern Ocean where it spreads into the northern Pacific and starts to gradually upwell along the Equator, becoming shallower as it does so. It eventually reaches the surface in the northern Pacific before returning to the North Atlantic as part of the upper warm water circulation.

This general circulation pattern is very important to us as its close coupling with the atmospheric circulation allows it to play a dictatorial role in determining our climate and thus other factors such as the global distribution of biomes. The Gulf Stream is responsible for the temperate climate we experience in the UK – a climate that is much milder than countries of similar latitude. The upwellings and downwellings that occur within the circulation are linked to the productivity of the oceans and the currents themselves allowed for the early navigation of the oceans, thus aided development. However, the current pattern has not always existed and is vulnerable to many external factors and cyclic atmospheric changes in the future. The cessation of the thermohaline circulation and possible alterations to the current pattern could be provoked in the future by many external forcing factors and the outcome of such an event would have a huge, although in the long run not irreversible, impact on us.

I realise that it is rather lengthy but I hope it didn't bore you too much! This is kind of what I would class as the basics of ocean circulation and there is lots more (especially a lot of maths!) and so if you have any questions feel free to ask them and I will try to answer them. Some posts on some of the more scientific stuff that I have been learning with the Met Office, like things linked with vorticity and its importance etc, will be appearing soon! Like I said before any comments would be greatly appreciated!

UN officially declares a famine in Somalia

Last week, the UN officially declared a famine in two regions of southern Somalia. This is the first famine to hit Somalia since 1992 and although it is currently contained in the regions of Bakool and Lower Shabelle, there are fears that this famine could spread throughout the rest of the country. The UN estimates that 2.5 million people in Somalia are in desperate need of assistance so why exactly has it taken so long for it to be officially classed as a famine?

Well, the main reason is that to define a famine is slightly more complex than simply a shortage of food, as some may think. In 2005, the UN established criteria to provide guidance to those needing to declare a famine and to help them allocate their limited resources. Therefore, the UN ranks food security into 5 stages, with famine being the fifth and most severe. They created 3 conditions that have to be met before a famine can be declared:-

- 20% of the population must have fewer than 2100 kilocalories of food available per day
- More than 30% of the children must be acutely malnourished
- 2 deaths per day in every 10,000 people or 4 deaths per day in every 10,000 children must be caused by a lack of food

National Governments have the responsibility to declare a state of famine but, due to the fear of the long term detrimental impact doing so could have on the way the country is perceived, many governments are reluctant to do so. In the case of Somalia, the UN had to step in and take control of the situation as there is a lack of central government in the country.

Until this month, aid agencies had been banned from working in quite large parts of Somalia by the Al-Shabab group, who exercise control over much of southern and central Somalia. It is hoped that the declaration of famine in southern Somalia will provoke greater international efforts to help tackle the situation, which is only likely to get worse without international intervention.

The worst drought in over half a century being experienced in the horn of Africa is to blame for the famine. So, what has created this bad drought?

Think back to the really bad floods experienced in Australia, Sri Lanka and Brazil earlier this year. Well they were caused by La Nina, however, La Nina does not increase rainfall across the globe and in fact, in some areas, it can drastically decrease rainfall. This is the effect that La Nina is having on the horn of Africa and it is one of the principal reasons why this area is experiencing a drought. The hope is that once the switch to El Nino occurs the rainfall will start again but at present, it could be a while until this switch occurs as there are no apparent signs that this is happening. Another factor that is believed to have made this drought so bad is the fact that the temperature of the Indian Ocean is warmer than it has been in previous years. This has provoked an increase in the precipitation over the sea which has reduced precipitation over the land. The rains have failed for three successive rainy seasons and two should occur each year (May to March and October to December).

The drought is, perhaps, the most influential contributory factor that has generated the famine but it is not the only reason…….

Conflict in the area has generated thousands upon thousands of refugees who further increase the population density of the area, meaning that there are more mouths to feed. Many of these refugees have been forced into Kenya and Ethiopia who, respectively, have a predicted 3.5 million and 3.2 million people in need of immediate assistance and this has only acted to increase the food and water shortages in these two neighbouring countries. Conflict, combined with other factors, has led to increases in both food and fuel prices, thereby meaning that affordable food is more and more of a problem. Farmers currently have to sell 5 goats to enable them to buy one 90kg bag of maize. One of the biggest issues is that around 65% of the population are Pastoralists and so make their living by raising and grazing livestock. The drought has caused many of their animals to die of dehydration, thus depriving people of their only food source and income. The lack of development in Somalia is responsible for leaving the Pastoralists vulnerable to such climate extremes as that currently being experienced as a lack of infrastructure, primarily roads and market centres, has closed off their easiest route to prosperity – something which many believe would insulate them from climate extremes.          

The conflict and control exercised over many regions of Somalia has slowed, and in some cases prevented, the aid getting through to the people who clearly so desperately need it. The UN has announced that they will begin airlifting food to Somalia on Tuesday and the World Bank has pledged $500 million in monetary aid - $12 million of which is being used for immediate assistance to the worst hit areas in East Africa. With more than 10 million people estimated to be at risk of starvation; the aid effort needs to be an internationally united one if it is to have the required effect. However, the aid effort cannot stop as soon as the food shortage has been solved. Money needs to be spent on making farming practices in Somalia more sustainable and productive so that food shortages are not a problem in the future. It is true that climate extremes such as the current drought, which has been triggered by La Nina, cannot be prevented but their impacts could be reduced. Improving transport links and infrastructure between rural and urban areas would allow for easier and more effective trade – something which would help prevent people for being isolated by similar climatic extremes.

This situation is far from being remedied and so if I were you I would monitor it and the effectiveness of the aid effort – this is an issue that could be linked easily to the Development and Globalisation module.

Are the 'Four Asian Tigers' a good model for developing countries?

The Four Asian Tigers have developed in a slightly different way to most of the other developed countries in the world. The question is though; is their chosen path of development one that developing countries should follow? And, if so, is this the contemporary way to develop?

Before I can answer these questions, I think I need to go back to the very beginning...........

Who are the Four Asian Tigers?
The term the Four Asian Tigers refers to the countries South Korea, Taiwan, Hong Kong and Singapore (and primarily their economies) and the term started being commonly used in the 1970's. They are grouped in this way as since the 1960's they have all followed a similar path to development and went on to reach the fully developed status at the start of the 21st Century.

What did the Tigers do differently in terms of provoking development?
The conventional step taken to kick start development in the 1960's was to implement import substitution. This involved raising tarrifs to reduce the imports of consumer goods and thereby allowing a country's own industries to develop and stabilise. The Asian Tigers, however, decided to capitilse on the growing materlistic attitude developing in much of Europe and North America and so pursued an export-driven model of industralisation and development instead and this was achieved by rapidly increasing the production of goods that could be exported to the highly industralised nations of the world.

What common characteristics did the Tigers share?
These four countries have experienced very rapid growth and have had many things in common as they have done so:
- All four territories had a strong degree of Chinese influence, with most having a large ethnic Chinese community. Singapore had a population that included 75% ethnic Chinese, Hong Kong had 95% and Taiwan had 98%.
- They were relatively poor during the 1960's and had an abundance of cheap labour.
- They had non-democratic and relatively authoritarian political systems during the early years, so the governments could easily drive through their plans for economic development.
- They focused their development drive on exports to richer industralised nations rather than focusing on import substition, which meant that they built up trade surpluses with the industralised countries.
- The Tigers singled out education as a way of improving the productivity of the labour force and so they ensured that all children attended primary and secondary school. They then went on to invest heavily in the development of their university systems and in sending students to foreign universities.
- Domestic consumption and purchase of consumer goods was discouraged at first and this was done by placing a high tariff on imports. This high tariff on imports led to the encouragement of high saving rates which then allowed for specific areas of industry to be invested in.
- Trade unions were discouraged and in their place, governments encouraged managers to provide job security and other benefits in a paternalistic type of industrial organsiation.
- They all sustained double-digit rates for growth for decades.
- While industry was developing, agriculture was protected by subsidies and tariffs on non-essential imports. Land reforms were created to ensure that small and medium-sized farmers had security of tenure, which, in turn, encouraged them to invest in their land. This resulted in a cease in rural discontent and also allowed investment in the mechanisation of agriculture which released rural workers from the land and enabled for further industrialisation to occur.

Good or Bad???
This method of development seems to have worked for the Four Asian Tigers as, at the start of the 21st Centruy, they had all reached high positions in the ranking of countries by total GDP but is this path to development applicable to other countries or, in fact, should developing countries be encouraged to use the Tigers as role-models and therefore mirror they way in which they developed?

Well the Asian Tigers have received quite a bit of criticism from economists and geographers and their development has not been as smooth as it may first sound.

The biggest criticism they have faced is focused on the fact that they have relied on exports, at the cost of home demand, to develop. This has left the Tigers incredibly reliant on the economic health of their targeted export nations - a very risky factor to rely on! Their early development was also based on the utilisation of their abundant cheap labour force; which has now been rivalled and surpassed by the likes of China and India; who are agruably emerging as almost like the new tigers as they have incredibly fast growing economies.

However, fast expansion of a country's economy is not necessarily a good thing and, in the 1990's, the Four Asian Tigers learnt this lesson the hard way. Their economies had expanded so fast (too fast in reality) that their growth provoked the prices of properties, stocks and shares to become overvalued. This caused several of the stock markets to collapse, thereby creating a worldwide financial crisis. After much social unrest and political instability the Tigers had to recieve help from the International Monetary Fund.

Thankfully, since the 1990's crisis most of the Tiger economies have become finanically stable and now have stronger companies and regulatory frameworks in place to prevent another similar crisis. However, this has shown many Asian governments that the easy and predictable prosperity of export-led growth and cheap labour costs will not last forever. The emerging manufacturing giants of China and India are forcing the Tigers to look into creating new industries that add more value and create stronger service sectors to help provide strong demand at home, so that they can compete.

The question I really want to answer though is, should developing countries try and copy the journey taken by the Tigers?

I am not really sure, to be honest, and there is clearly no right or wrong way to develop. The 1990 crisis shows that it is ever so dependent on the economic health of other countries - something I think is extremely risky in the current global economic climate. I also question just how sustainable this development is, due much in part to its dependency on many influential factors beyond their control, but then again, as I do more and more reading around the subject of development, I struggle to see if development as we know it is actually sustainable at all (another rather large debate though so perhaps I will leave it for another blog post!). On the other hand, it seems to be an alternative to what I think I would class as the 'old-fashioned' development that utilised colonialism as the building blocks/foundations and so could, perhaps, be used be other similar countries. So, what do you think, are the Tigers a good model for other countries?

Geography Picture of the Day - Volcano erupts on Sulawesi

Thousands of people have been forced to flee the Indonesian island of Sulawesi after Mount Lokon started erupting yesterday afternoon. As yet, there have been no reports of casualties but this is perhaps thanks to the fact that over the last month there has been a significant increase in volcanic activity in the area and so people were already aware of a possible eruption. Only two days ago the alert status was raised to the highest level. Prior to the eruption a two mile evacuation zone was established and, so far, 4,400 of the 28,000 people that live in that area have been evacuated - the evacuation process is still underway.

The 1,580 metre, Mount Lokon is one of the most active volcanoes in Indonesia - although there are many - and it last erupted in 1991. This lastest eruption has seen ash, sand and rocks thrown some 1500 metres into the air.

Yet another volcanic eruption - I would keep an eye on the situation!

Gaia, by James Lovelock - A student's book review

I read this book over a week ago now but have been putting off writing a review as I was not, and still am not, 100% sure what excatly to say - but I am going to give it go!

This book puts forward the idea that the Earth functions as if it was a living organism and is entirely based on the Gaia hypothesis. The Gaia hypothesis suggests that the physical and chemical condition of the surface of the Earth, of the atmosphere, and of the oceans has been and is actively made fit and comfortable by the presence of life itself. This is in contrast to the conventional wisdom which held that life adapted to the planetary conditions as it and they evolved their seperate ways - this describes the original Gaia hypothesis which is now acknowledged to have been wrong. It also includes the belief that life does not regulate or make the Earth comfortable for itself. Lovelock believes that regulation, at a state fit for life, is a property of the whole evolving system of life, air, ocean, and rocks and that, since it has a mathematical basis in the model Daisyworld and makes testable predictions, can be known as the Gaian Theory. The Gaia theory is not contrary to Darwin's discovery of evolution by the process of natural selection but instead is a development of it and this book is, essentially, the account of a journey through space and time in search of evidence to support Lovelock's interesting view - one that I have to admit have never given much thought to - of our planet and all the organisms that inhabit it.

The book is constantly asking questions - all of which are extremely thought provoking - but one of the first is what is life? When I first read it, I thought what an odd question to ask, but try defining it......... I spent ages trying to do so but got absolutely no where!

To put you out of your misery, the definition given in the book is "A common state of matter found at the Earth's surface and throughout its oceans. It is composed of intricate combinations of the common elements hydrogen, carbon, oxygen, nitrogen, sulphur and phosphorous with  many other elements in trace quantities. Most forms of life can instantly be recognized without prior experience and are frequently edible. The state of life, however, has so far resisted all attempts at a formal physical definition. " So, did you get anywhere close to that? 

Anyway, the book investigates knowledge of various feedback systems to try and prove that the Earth, as a living organism, responds to changes in conditions - some of which are as a result of our existance like pollution - to maintain a state of constancy. There are numerous examples of this and, of course, a few links to the future and climate change.  

Overall, I would suggest that any Geography student reads this book. I must mention though that is was written a while ago and so there are some scientific mistakes which, in the new added preface the author does address and explains why he chose not to correct them. Despite it being intended for the non-scientists it does include quite a bit of science (although, on reflection, not in much challenging detail) - especially Chemistry. It covers a wide range of topics related to Geography but be warned, you need to read this with an open mind and it will make you think an awful lot!

I am sorry that this is such a bad book review but this book presented so many new and intriguing ideas that I am still trying to process. So, all I can really say is read it and then let me know what you think!!!

Blood Diamond - A student's film review

My Geography film of the week this week was Blood Diamond - a film I had never previously watched but a family member suggested it might be of interest to me in relation to the Development and Globalisation module..... and they were right!

Blood Diamond is set during the explosive 1999 civil war in Sierra Leone and follows the story of the unlikely friendship that develops between an ex-mercenary turned smuggler, a Mende fisherman and a journalist who is trying to make the Western world aware of the dire situation in Sierra Leone. These people are forced to join together as they try to complete seperate, but all desperately dangerous, missions : recovering a rare pink diamond of immense value, rescuing the fishermen's son who has been conscripted as a child soldier into the brutal rebel forces and telling the story, to the rest of the world, of the origins of the diamonds that the comsumers in the developed world desire at the lowest possible price.

 

I don't want to give to much away about what happens in the film as I think it is one of those films that is intended to shock you!

Is it a good Geography film to watch? Definetly!!! This film covers numerous issues that I am sure are going to be raised as we continue to move through the Development and Globalisation module. You get an immediate insight into life in Sierra Leone - a country that alternates between times of peace and beauty and times of bloodshed. The film forces the issue of the diamond trade upon the watcher and makes them see the impacts that the desire of the developed world for affordable diamonds has on the people of exploited coutnries, like Sierra Leone. Afterall, without a consumer there would be no market for the trade of such goods. This made me think about lots of things but one thought that stuck in my mind was, what would the countries of Africa be like today if they didn't have the raw materials that the Western world wants to exploit? Would we have still colonialised the countries? Would we still ensure some sort of control/influence in them today? And so, essentially, how has their abundance of resources, such as rare earth minerals, influenced their development? One of the other issues that features throughout is that of the civil war and the impacts it has had on the country and its people. Unfortunately, children in many countries are still conscripted as child soldiers by rebel forces. Much of the civil war experienced throughout Africa is, arguably, an unintended, detrimental, side-effect of colonialism (this is rather a big topic so I will leave this for a future blog post!) and so, in preparation for our first essay when we go back; this is quite a good film to watch as an introduction to the topic. So,overall, I would recommend that you watch this film as it makes you think about quite a few key issues surrounding African development, influences of the developed world and the impact of colonialism.

A Painted Veil - A student's review

I watched this film a while ago and whilst doing some research for the group work we had to do over the past few weeks (my group did Haiti) I realised that its link to Geography was not as tenuous as I first believed.

The film is based on the classic novel by W.Somerset Maugham and, set in 1920, follows the story of a young English couple, Walter, a middle-classed doctor, and Kitty, an upper-class woman. They get married for the wrong reasons and relocate to Shanghai, where she falls in love with someone else. Then, in an act of venegance when he uncovers her infidelity, he accepts a job in a remote village in China ravaged by a deadly epidemic, and insists that Kitty accompany him - and this is where the link to Geography can be found!

The deadly epidemic that is ravaging through the Chinese village is cholera; the same water-bourne disease that claimed so many lives in Haiti after the earthquake last year. The film provides an insight into the causes of cholera and why it is such a huge problem in underdeveloped countries. It claims so many lives and simple things like a safe, clean water supply and sufficient sewage systems prevent it from doing so. It also demonstrates the issues surrounding the prevention of the spread of this water-bourne disease, with particular reference to the impact of religious beliefs - especially burial traditions. Many people, like the villagers in the film, like to hold on to the bodies of the dead for a while before burying them, often near water sources. This often further fuels the epidemic and this issue is something that is common between the film and the aftermath of the 2010 Haiti earthquake. The film also presents the oppurtunity for the watcher to make comparisions between the level of development (bearing in mind it is set in 1920) in London, Shanghai and the Chinese village experiencing the cholera epidemic and also touches on the political instability present at the time in China.

So, is this a good Geography film? Well, its link to Geography is slightly more tenuous than some of the other films I have watched lately, but it is still definetly worth a watch! Throughout you get to see some spectacular footage of the Chinese countryside and you get an insight in what life was like in China at that time. The reflection, provided by the film, of the impacts of cholera on a region can easily be linked to our current module and helps you to gain an understanding of the issues that Haiti faced whilst trying to deal with the cholera outbreak, whilst also dealing with the aftermath of the devasting earthquake.