Rivers Discharge More Water Into Arctic Ocean

The Lena Delta, Landsat 2005, Alfred Wegener Institute. 
Today the three Russian rivers Lena, Ob and Yenissey discharge more water in the Arctic Ocean than they did 60 years ago. That’s the result of a study undertaken by an international team of researchers, which was published yesterday in the scientific journal Nature Climate Change. 
Each year these three rivers discharge an estimate of 1700 cubic kilometer of water into the Arctic Ocean. That is ten per cent more than they did 60 years ago”, says Prof. Rüdiger Gerdes, scientist at the Alfred Wegener Institute, who participated in this study.
The scientists had analyzed, if changes in atmospheric circulation are the driving force of accelerated river discharge. One example for a change in atmospheric circulation is the recent shift of the so-called Icelandic low-pressure system to regions further east. “Today air masses, which never made it to the basins of Lena, Ob and Yenissey before, reach those regions and bring a lot of moisture with them. Because the warmer the air gets, the more moisture it can contain”, Rüdiger Gerdes says.

In his opinion the accelerated river discharge into the Arctic Ocean will even further increase – du to global warming. Until now the growing input of river water hasn’t had any evident consequences for the Arctic Ocean. Its increasing body of fresh water is based on the decreasing volume of arctic sea ice, Rüdiger Gerdes says.

The study with the title: “Enhanced Poleward Moisture Transport and Amplified Northern High-Latitude Wetting Trend“ can be read here.