Uneven twins? The case of Lake Chad and the Aral Sea

One reader recently commented my blog post on the Lake Chad asking after similarities and differences between the development of the Lake Chad in West Africa and the Aral Sea in Central Asia. When answering that question I had a closer look at this odd pair. Further research conducted very much caught my attention – I will thus dedicate this post to the fates of these two lakes.

Besides being listed on the List of 7 Lakes That Are DryingUp by the Encyclopaedia Britannica the two transboundary lakes are frequently mentioned in the same breath (Okpara et al. 2016) despite their geographical dispersion - see for yourself on the map I inserted underneath. 

Sidenote: The name the Aral Sea is somewhat misleading. The name originates from times when it extraordinary proportions led to the assumption it was, in fact, a sea. It is not.

11. Both used to be of exorbitant sizes: The Lake Chad was formerly the fourth largest lake in Africa with a surface area of up to 25,000 km² in 1993. The Aral Sea could be something like the distant big brother with a surface covering an area of 68,000 km² in 1960.

22. Both have experienced a remarkable development since the 1960s. Today, the Lake Chad has shrunk to less than 10% of its former volume. The Aral Sea has decreased volume since 1850 until today, the former lake is transformed to four very small lakes (also less than 10% of its former size in total).

33. Today, both lakes are on the edge of vanishing, though the original Aral Sea has technically vanished already whereas the Lake Chad is significantly smaller but still ‘there’.

When discussing their development, in reports on both lakes one might stumble across ‘climate change’ and ‘irrigation’ as relevant factors. However, when examining the causes of their developments and the arising challenges for the individual regions it becomes apparent that the two lakes are just more uneven than one might assume on first sight.

The Lake Chad as examined in a previous post has historically experienced high variability in its sizes, throughout the course of the year as well as through different centuries and was subsequently on the edge of drying out twice before (1908 and 1884). One factor considered responsible for its variability is the location where high precipitation variability and frequent droughts are common (Okpara et al. 2016). Further, its bathymetry increases vulnerability to shrinking. Additionally, the so-called population explosion throughout the last decades in the area generating a corresponding demand in water for both domestic use and irrigation for subsistence economy are considered key factors for the lake's development (GIZ, 2015). The impact of these mentioned factors is further likely to get intensified through climate change and more large-scale irrigation schemes.

Moving up north-east, the Aral Sea has been faced with a slightly varying set of pressure factors. For the first half of the 20th century, inflow by the Amu Darya and Syr Darya River and evaporation of the lake were almost even causing a comparatively steady water level. The primary economic activity enhanced by the lake was the fishery. However, the driving force behind its shrinking can be traced back to sudden large-scale irrigation from the two rivers and the lake directly, in particular for the cotton and rice industry enhanced by the Soviet Union regime. This quite rapidly led to a split up of the lake into two smaller lakes. First dam projects intending to protect at least one of the two lakes from further shrinking failed to allow the lakes to decrease further, Micklin (2007) states. 

Both basins sustaine(d) an incredibly large number of people. When looking at the consequences for the specific regions posed by the developments the difference is remarkable. Amongst the directly affected by the Lake Chad, we find small-scale farmers. Their coping strategies include a change in crops and a focus on different economic activates other than farming to generate an income. The amount of fish caught has more than halved. However, since parts of the lake still exist fishery is still a vibrant economic sector. Even though the decrease of the lake size is drastic, Béné et al. (2008) found that some livelihoods are not affected directly providing the location offers other resources. This again leads to large-scale and partially cross-border migration around the basin towards these locations. Subsequently, the lake development is considered a significant driver of increased social and economic vulnerability. This again fuels conflict and rising extremism around the four country borders.  

The European Council on Foreign Relations shows the dilemma of local communities. Climate Refugees around the Lake Chad. Source: www. ecfr.eu (2017)

The Aral Sea for in contrast experiences a different set of consequences. Here the collapse of the fishery industry left numerous tens of thousands of people unemployed. However, the cotton industry in Uzbekistan which majorly relies on irrigation could mostly be protected through diversion of the lakes. That large-scale cotton production around the lake has left the entire basin covered with highly polluted sediment originating from the extensive use of pesticides on the cotton fields (Micklin, 2007). Together with the high level of salt and the lack of water, dust storms transporting the salty and contaminated sediments for incredibly long distances are a present and dangerous threat for the environment, the agricultural land and the health of people. Between 2000 and 2009 13 dust storms occurred per year (UNEP, 2010). 

Dust storms around the Aral Sea. Source: earthobservatory.nasa.gov (2008)

Combating these consequences requires extensive vegetation cover, improved and sustainable health care and decreased use of pesticides.

Zooming back out, it becomes apparent, that the two lakes might be called distant cousins. Both of their developments have severe long- and short-term implications. It turns out, that the short-term consequences are much more alike – after all, the two lakes firstly pose an economic burden for local communities affected. In the long term, the challenges arising are quite different.  Whereas large-scale contamination has become an international health and environmental crisis thanks to dust storm around the Aral Sea, the west-African lake development has transformed the region into a potential hotspot for terror fuelling global terror-politics. Here, the silver lining might be the prospect of the comeback of some light version of the Lake Chad.