Monday, November 07, 2022

The Climate Threat to the Nile

 At more than 6,600 kilometres long,  the world’s second-longest river, the Nile,  extends to 11 countries, including Tanzania, Burundi, Democratic Republic of Congo, Rwanda, Uganda, South Sudan, Ethiopia and Egypt, it is essential to the survival of millions of people living in Africa. But a combination of climate change and human overuse is drying up the river, and worsening conditions for farmers who fear low harvests and loss of electricity. 

In the past 50 years, the flow of the Nile has fallen from 3,000 cubic metres per second to 2,830. 

A lack of rainfall and increased droughts expected in East Africa means river flow could fall by 70 percent by 2100, according to UN forecasts.  The UN has predicted a loss of 75 percent of available water per local inhabitant. Related land erosion, crop loss and lack of electricity are also likely to have a dramatic impact on the millions of people living in Africa who rely on the river for survival.  

 Located between Kenya, Uganda and Tanzania, Lake Victoria is the largest supplier of water to the Nile, with the exception of rainfall. Yet evaporation, lack of precipitation and changes in the tilt of the Earth’s axis mean the lake is now at risk of disappearing. One 2020 study analysed historical and geological data from the past 100,000 years and found that the entire body of water could vanish in the next 500 years. This would have a striking impact on the Nile, a river whose basin covers 10 percent of the African continent and which is an essential resource for 500 million people living in its vicinity.  

In Egypt and Ethiopia, lack of access to water among people living along the Nile is already an issue due to politics rather than climate change. Priority of access is currently given to large-scale agricultural businesses as opposed to local inhabitants. There is a lot of competition for water intensified by agribusinesses that grow produce for export. Policies that aim to export water from the Nile in the form of tomatoes or cucumbers do not take into account the local populations that need this water. Climate change threatens to worsen the situation for millions of people. Lower water levels due to global warming will impact those who are already the most in need.

In the Nile Delta – the sediment-rich landform where the river meets the Mediterranean Sea. This area is one of the three locations in the world most vulnerable to global warming, according to the Intergovernmental Panel on Climate Change, as the weakened flow of the river struggles to push back the sea’s rising water levels. Every year since 1960 the Mediterranean has worn away between 35 and 75 metres of earth in the Nile Delta. If it were to rise by one metre it would submerge 34 percent of the surrounding region in northern Egypt, displacing 9 million people.  

Dwindling river reserves are worsening the problem. The less water there is in the Nile valley, the more the Nile Delta will be invaded by water from the Mediterranean. This does not just bring the risk of ground erosion and flooding, but also changes the composition of the river. The layer of groundwater beneath the river delta is increasingly made up of saltwater from the Mediterranean as less and less freshwater is arriving.   Along the northern banks of the river the water is becoming more saline. Very little drainage water (freshwater from the river) is making it to the Mediterranean; less than 1 billion cubic metres of water, which is ridiculous compared to what there was 40 or 50 years ago. Already, salt from the Mediterranean has polluted hectares of land, weakening and killing plants. Farmers have reported a reduction in the quality of vegetables.Already, salt from the Mediterranean has polluted hectares of land, weakening and killing plants. Farmers have reported a reduction in the quality of vegetables.

if temperatures continue to increase, the Mediterranean will advance 100 metres into the Nile Delta each year. Over time it estimates the Mediterranean could swallow 100,000 hectares of agricultural land situated at less than 10 metres below sea level. This would be catastrophic for Egypt, where the north of the country accounts for 30 to 40 percent of national agricultural production.

In the 10 countries that the Nile runs through, the river is not just a source of water, but also of energy. Sudan generates more than half of its electricity resources from hydropower. In Uganda, the figure rises to 80 percent.  But this energy source is becoming increasingly unreliable. If rainfall goes down, water levels in Lake Victoria and the Nile will go down as well, which will reduce hydroelectric production. In Uganda electricity cuts are already a frequent occurrence.

 In Ethiopia, the Grand Ethiopian Renaissance Dam (GERD) aims at creating 13 turbines capable of producing 5,000 megawatts of electricity per year. Since August, 22 billion cubic metres of water have been stored in the dam’s reservoir, which has a total capacity of 74 billion cubic metres.  Egypt fears a drastic reduction in the flow of the Nile if the GERD fills too quickly. In Egypt, farmers have already seen the effects of the Aswan Dam – one of the world’s largest embankment dams. As with dams in Ethiopia, Uganda and Sudan, it has reduced levels of silt – a precious natural fertiliser – in the water. 

Crisis on the Nile: Global warming and overuse threaten Africa’s longest river (france24.com)



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