According to the National Oceanic and Atmospheric Administration, global sea levels have been rising over the past century, and the rate has increased in recent decades. Sea levels are currently rising about one-eighth of an inch every year.
Sea level rise is caused primarily by two factors related to climate change: the added water from melting glaciers and ice sheets, and the expansion of seawater as it warms. While climate change is causing global sea levels to rise, higher temperatures in other regions are having exactly the opposite effect. The water levels are falling.
According to researchers from the University of Bremen in Germany, the Caspian Sea is a perfect example of how a body of water will change. While it is named a sea due to its size and high salinity, the Caspian Sea is actually a lake. In fact, it’s the largest lake in the world. Its largest inflow is the Volga River and it has no natural connection to the ocean. Its water level is determined by the proportional influences of inflow, precipitation, and evaporation. Climate change is causing increased evaporation, which leads to a declining water level.
According to the research team, the water level of the Caspian Sea could fall by 29 to 59 feet during this century.
The Caspian Sea is surrounded by Kazakhstan, Turkmenistan, Iran, Azerbaijan and Russia. It’s an important regional water reservoir, and a biological and commercial center.
The researchers hope the Caspian Sea will be used as an example in scientific research to assess the vulnerability of other regions to falling water levels.
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Climate crisis is causing lakes to shrink
Photo, posted October 31, 2016, courtesy of Amanderson2 via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio.