The Arctic is Getting Rainier

The Arctic is known for its cold temperatures, which allow precipitation to fall as snow. But as temperatures warm, that snow is being replaced by rain. These changes can affect sea ice in the Arctic and weather patterns throughout the Northern Hemisphere. NASA scientists examined rainfall trends over the Arctic and North Atlantic oceans from 1980 to 2016 and found an increase in the frequency of rainy days. They also found that the length of the annual rainy season grew longer. The results were published in the Journal of Climate.

The most dramatic changes took place in the North Atlantic, where it rained on average five more days per decade at the end of the 36-year study period than at the beginning. The rest of the study region—the central Arctic Ocean and its peripheral seas—saw an average of two additional rainy days per decade. This comes as temperatures in the Arctic are warming four times faster than the rest of the planet.

The map above shows the change in number of rainy days per year, which has contributed to this decadal trend toward a rainier Arctic. It is based on the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), a global reanalysis product developed by NASA’s Global Modeling and Assimilation Office. The product takes in-situ and satellite observations, including from NASA’s Atmospheric Infrared Sounder (AIRS) on the Aqua satellite, and uses them to reproduce conditions that have occurred across the globe.

Source: ENN