Spatial Shift of Greenland Moisture Sources Related to Enhanced Arctic Warming

Understanding the atmospheric moisture budget of Greenland is critical for predicting future Greenland climate. However, past attempts to quantify the provenance of Greenland precipitation have been limited to certain seasons. Here we present an analysis of Greenland moisture sources using water tracers in the Goddard Institute for Space Studies climate model, which can provide source estimates for all time periods. The North Atlantic is found to be the dominant moisture source, except during summer when continental sources increase substantially. The variability is also found to be partially correlated with the Greenland Blocking Index. The key finding, however, is a long-term trend in the moisture source location for Northwest Greenland, with an increase in more locally sourced moisture over time during nonsummer months. This is at least partially related to sea ice loss in the Baffin Bay region, along with a larger increase in sea surface temperatures for the region relative to other locales.