Shocking satellite images of lakes show extent of man's impact on world's water supply
July 3, 2010 § Leave a comment
These dramatic before-and-after satellite photos show the terrifying effect man is having on the world’s resources. Taken over nearly 40 years, photographs show the drying up of several bodies of water around the world – receding as mankind’s demand for water grows. Included in the shocking collection is the once mighty Aral Sea in Central Asia. The expanse of water, like several others across the globe, has been reduced to worryingly sparse levels. In April the situation at the Aral Sea was described as ‘one of the planet’s worst environmental disasters’ by UN Secretary General Ban Ki-Moon.
Shown here in images taken from space between 1973 and 2009, slowly but surely the Aral – in fact a salt water lake – has shrunk from being the size of Ireland to a cluster of contaminated ponds. An inland lake, the Aral is found between Uzbekistan and Kazakhstan and used to be the fourth largest lake in the world. Since the 1960s, it has lost more than half of its volume. The drying is due to overuse of the lake’s feeder rivers. In the 1960s the former Soviet Union diverted the Syr Darya and Amu Darya for the irrigation of cotton and paddy fields. Now 50 years later the water is at a dismal 10 per cent of its level when the projects first began. So great was the impact on the region the local climate was thought to have changed and pollution has risen to dangerous levels. The destruction of the lake has also decimated the local fishing industry, causing severe knock-on unemployment and further economic woe for the people living around it.
Across the globe once rich and fertile lands are facing the same catastrophe. Arid and desolate Iraq was once a green, lush environment even reputed to be the setting of the Garden of Eden. Seen from above between 1973 and 2000 the Mesopotamia marshlands straddle the borders between Iraq and Iran near the mighty Tigris and Euphrates rivers.
The marshes were systematically drained in the mid- to late 20th century. This was done to provide agricultural land, but also to destroy the habitat of the Shi’a Muslim Marsh Arabs, who were persecuted by the Iraqi ruling Ba’athist Party. Also included in the before-and-after pictures are the Toshka Lakes, in southern Egypt. They were formed in the 1990s by diverting water from Lake Nasser, an artificial lake formed behind the Aswan High Dam on the river Nile. The region was planned to be a major new agricultural and industrial site for Egypt. But as these images show, the region is drying fast.
One image taken in March 2001, shows the lakes near their maximum capacity. A later satellite picture from December 2005 shows how the waters receded due to drought and rising demand for water, leaving a ring of brown wetlands around the edges of the lakes. Lake Chad, located in the Sahel region near the Sahara, was the fourth largest lake in Africa in the 1960s and had an area of more than 10,000 square miles. But by the 21st century it had shrunk to less than 600 square miles – around a twentieth of its size. This was caused by increased use of irrigation combined with severe droughts.
The Toshka Lakes in southern Egypt were formed in the 1990s by diverting water from Lake Nasser, an artificial lake that formed behind the Aswan High Dam on the river Nile. The region was planned to be a major new agricultural and industrial site for Egypt but as these images show – between 2001 and 2005 – the region is drying fast.
The waters have receded, leaving a ring of brown wetlands around the edges of the lakes, because of drought and a rising demand for water in the area. Dr Benjamin Lloyd-Hughes of the Walker Institute for climate system research, University of Reading, said: ‘Ultimately the disaster seen at the Aral Sea and the marshes are the combined effects of man and rising temperatures in those regions. ‘There has not been much change in rainfall in those areas but the temperature has risen by over 1 degree Centigrade since 1970, which will have enhanced losses due to evaporation.’Pollution in the area will have become worse because as the water evaporates, pollutants in the water become more concentrated and less diluted.’
At Lake Chad and the Toshka Lakes the same effect of man in combination with climate change has been observed. Dr Lloyd-Hughes added: ‘There has been a 30% reduction in annual rainfall since 1900 in these regions but not a significant change in temperature. ‘Reductions in lake levels here seem to driven by reductions in rainfall rather than increased evaporation.
The outlook is that there will be no change in rainfall but temperature could increase by another two degrees Centigrade by 2100. This is not good but not so bad as for the Aral Sea and Mesopotamia.’Global warming is a problem that is happening everywhere but if drought is happening in your region then it is a far greater problem. With the growth of mass-agriculture to feed a severely ballooning global population, water demand has begun to perilously outstrip supply, making disasters like the Aral Sea a grim and alarming likelihood for the future.