Water and Environmental Change in Africa: The Lake Chad Region and beyond

In my last post I discussed environmental change in the Lake Chad Region in comparison to that of Lake Victoria, the largest lake in Africa. What is even more startling than the comparison between Lake Chad and Lake Victoria is the comparison between the current extent of Lake Chad and Lake Mega-Chad (LMC).  Figure 1: Location maps of Lake Chad. (B) shows Lake Mega-Chad's catchment and (C) shows the  extent  of present-day Lake Chad (as of 2015)  compared  to Lake Mega-Chad. Source: Armitage et al. 2015 The surface area of LMC is thought to have exceeded 350,000km 2 , a similar area to that of the Caspian Sea, currently the largest lake on earth ( Bouchette  et al . 2010 ). LMC was the largest Quaternary body of water on the African continent. The extent of LMC is thought to have peaked around 6,000 years ago at the end of the African Humid Period. Figure 1 shows that extent of LMC compared to its basin and the current extent of Lake Chad. ...

'Lake Chad offers a grim cautionary tale of how lessons from chronic drought might inform our anticipation of the potential impact of climate change in many parts of Africa' ( Juma 2017 ). This quote reflects part of my motivation behind this blog. I chose to focus on Lake Chad as an example of the potential consequences of climate change on the African environment. This  article  in Quartz Africa goes on to suggest that Lake Victoria in East Africa is vulnerable to the same dramatic environmental change. Figure 1: Lake Victoria within it's basin, market by the black line. Source: NASA Earth Observatory Lake Victoria is Africa's largest lake, the world's largest tropical lake and second largest freshwater lake. For comparison, Lake Chad was once the 6th largest lake in the world ( Seipel 2006 ). Lake Victoria's basin (Figure 1) is small relative to the size of the lake and the majority of water input into the lake comes from rainfall directl...

The LCB is one of the largest sedimentary groundwater basins in Africa and it is characterised by 3 climatic zones: hyper-arid/arid, semi-arid and sub-tropical ( Vassolo 2012 ). Over 2/3 of the LCB occupies the arid-zone and hence does not provide water for maintaining the surface flow of the lake ( Candela et al. 2014 ).  The main source of recharge for aquifers in the LCB comes from the surface waters of Lake Chad and the rainfall it intercepts. However, this means that recharge can vary greatly as precipitation is unreliable and as a result, the aquifers are very sensitive to climatic change ( Global Water Partnership 2013 ). Rates of groundwater abstraction in the basin have been increasing since the mid-20 th  century and as a result, the Lake Chad Basin Commission was established to address water management issues. The Lake Chad Basin Commission (LCBC) The LCBC was established in 1964 by founding member nations: Cameroon, Chad, Niger and Nigeria ( Adenle 2004 ). ...

My last two blog posts described the influence of environmental change on agriculture in the Lake Chad region. I want to expand the scope of my research to a wider, continental scale in order to see if the problems faced in the LCB are mirrored elsewhere. Hence, I want to see if potential solutions to problems caused by environmental change can be transferred between different regions. South Africa Firstly, I have chosen to show the following video (Figure 1) as a comparison to the video in my last blog post. Figure 1 shows some of the problems being faced in South Africa due to increasing demand for water and dwindling resources. It is clear that this region is affected by low water  availability,  like in the LCB but the expression of this is very different. This reflects the idea that generalising the water 'crisis' in Africa is often counterproductive as water availability varies dramatically both spatially and temporally. Figure 1: Water shortages in South A...

Communities in the Lake Chad region have been adapting to climate change for decades or even longer by focussing their energy on different sources of income as the lake level changes seasonally, annually or over even longer timescales. Research from the WWF shows that many villagers in the Lake Chad region have shifted from relying entirely on fishing, to a more flexible approach to agriculture through farming the land surrounding the lake ( Gawler 2018 ).  Pastoralism  Climate change has had a large impact on pastoral farmers in the Lake Chad region. The ‘Small Lake Chad’ phase disproportionately disadvantages pastoralists who might have to travel over 50km to the waters, a problem which doesn’t affect fishermen or farmers to such a great extent ( Okpara  et al . 2016 ). The FAO are trying to mitigate the effects of climate change on pastoral farmers but with limited success thus far ( Nguyen 2017 ). A recent UN news article described how 80 people died in Nigeria...