10/25 (Fri) 12:06 cnn.co.jp (CNN) The Caspian Sea is the largest inland sea and the largest lake on Earth, with an area roughly equivalent to the state of Montana. Its curved coastline stretches for some 6,400 km and straddles five countries: Kazakhstan, Iran, Azerbaijan, Russia and Turkmenistan. These countries depend on the Caspian Sea for fishing, agriculture, tourism, drinking water, and oil and gas reserves. The Caspian Sea also regulates the climate of this arid region, bringing rain and moisture to Central Asia. But the Caspian Sea is in trouble. Damming, over-exploitation, pollution and the man-made climate crisis are accelerating the Caspian’s decline, leading some experts to worry it may be reaching a point of no return. Climate change is causing sea levels to rise around the world, but the story is different for inland seas and lakes like the Caspian. The Caspian Sea depends on a delicate balance between water flowing in through rivers and rainfall and water leaving through evaporation. This balance is changing as the planet warms, causing many lakes to shrink. If you look closely you can see what the future holds. The Aral Sea, which straddles Kazakhstan and Uzbekistan, was once the world’s largest lake but has been devastated and nearly disappeared due to human activities and the worsening climate crisis. For thousands of years, the Caspian Sea’s water level has fluctuated due to changes in temperature and the advance and retreat of ice sheets. But the rate of water loss has accelerated in recent decades. Human activities, such as the construction of reservoirs and dams by various countries, are having a significant impact. Of the 130 rivers that flow into the Caspian Sea, about 80 percent of its water comes from the Volga River, Europe’s longest river, which meanders through central and southern Russia. Russia has built 40 dams and has 18 more in the works, according to Bari Khaleji, an expert on Central Asia and the Caucasus at the University of Tehran. This is reducing the amount of water flowing into the Caspian Sea. Meanwhile, climate change is having an even more significant impact. Evaporation rates are increasing and rainfall is becoming more erratic. Water levels in the Caspian Sea have been falling since the mid-1990s but have accelerated since 2005, dropping by about 1.5 metres, said Matthias Prange, an Earth system modeller at the University of Bremen in Germany. Prange points out that a drop of between 8 and 18 metres is predicted by the end of the century. Some studies suggest that it could fall by up to 30 metres by 2100. The study’s co-authors say that even under more optimistic global warming scenarios, the northern Caspian Sea, mainly its shallow waters around Kazakhstan, would disappear completely. The situation is already dire for the Caspian Sea’s endemic wildlife. It is home to hundreds of species, including the endangered wild sturgeon that supplies 90 percent of the world’s caviar. Experts say the ocean has been surrounded by land for at least two million years, and its extreme isolation has allowed some highly unusual creatures, including cockles, to emerge. But lowering water levels could reduce oxygen levels at depth, potentially wiping out organisms that have survived millions of years of evolution. This is a massive crisis that almost no one knows about. The Caspian seal, an endangered species that only lives in the Caspian Sea, is also at risk. Their breeding grounds, the shallow waters of the northeastern Caspian Sea, are changing and disappearing. They also suffer from pollution and overfishing. Aser Baimukhanova, a researcher at Kazakhstan’s Institute of Aquatic Ecology, said aerial surveys had revealed a significant decline in the seal population. At one resting site in the northeastern Caspian Sea, 25,000 whales were spotted in 2009, but not a single one was spotted in the spring of 2020. There are few easy solutions to this crisis. The Caspian Sea is in a region that has seen a lot of political unrest and spans five countries. Each country will face the decline of the Caspian Sea in different ways.
Dams seem to just block water, but they actually reduce the amount of water significantly. People have finally realized this, which is why dams can no longer be built on Japanese rivers.
>>7 Well, I think the bigger problem is that the water they store has no other use other than for generating electricity. During the Showa era, they were expected to use it for paper manufacturing and other purposes, so they built it with that in mind. They thought they would be able to recoup the construction costs. But they ended up withdrawing, and the local waterworks corporations suffered huge losses.
You guys will dry up and die faster than the lake, so don’t worry too much. Start preparing for the afterlife, little by little. What preparations? Figure that out for yourself.
People always link it to climate change, but in the context of the Earth’s history, we’re stuck on a very short period of time, and it’s pretty presumptuous for humans to try to change (or reverse) the climate. What we need is not measures, but ways to respond.
>>42 It’s not that we should stop because it’s presumptuous, but rather that even if it’s presumptuous, we have to do it because if we don’t, we’ll perish.
The nearby Aral Sea is on the verge of disappearing due to environmental destruction, and the same thing is happening to the Caspian Sea. I don’t think it can be stopped or reversed.
Men love to build dams. I always wonder what they’ll do with the Three Gorges Dam, which is probably the biggest one they’ve ever had the budget for, even though they say it will be completed soon.
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