The Arctic Ocean has been getting warmer since the beginning of the 20th century – decades earlier than records suggest – due to warmer water flowing into the delicate polar ecosystem from the Atlantic Ocean.

An international group of researchers reconstructed the recent history of ocean warming at the gateway to the Arctic Ocean in a region called the Fram Strait, between Greenland and Svalbard.

Using the chemical signatures found in marine microorganisms, the researchers found that the Arctic Ocean began warming rapidly at the beginning of the last century as warmer and saltier waters flowed in from the Atlantic – a phenomenon called Atlantification – and that this change likely preceeded the warming documented by modern instrumental measurements. Since 1900, the ocean temperature has risen by approximately 2 degrees Celsius, while sea ice has retreated and salinity has increased.

Read the full article about Atlantification by the University of Cambridge at Environmental News Network.