Arctic Air Masses in a Warming World

Co-Author: Melissa Gervais

Co-Author: Eyad Atallah

Co-Author: John Gyakum

Co-Author: Bruno Tremblay

The purpose of this study is to understand how the internal variability of patterns of Arctic air masses might change in the future. To represent air masses, we look at patterns of equivalent potential temperature at 850hPa. We use self-organizing maps to define archetypical patterns of 850hPa equivalent potential temperature anomalies with respect to a changing climate. We can then examine changes in the frequency of occurrence of these patterns over the 21st century and propose mechanism for why this may be happening. Results from this study are in press at the Journal of Climate.

Further work will investigate some of the hypothesized mechanisms by which surface forcing might impact atmospheric circulation and air masses that were proposed in this paper. In particular, Melissa Gervais and Jeffrey Shaman at Columbia University plan to study how the North Atlantic warming hole influences downstream atmospheric circulation patterns using large ensemble experiments.