Links Between Arctic Amplification and Extreme Weather in Mid-Latitudes

• Main Authors: Jennifer Francis, Steve Vavrus
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.675.638; http://conference2011.wcrp-climate.org/posters/C11/C11_Francis_M123B.pdf

gov/psd/. Note large positive anomalies in surface temperatures, especially during fall and winter in close proximity to the ice pack, with evidence of effects of earlier snow melt during summer. Corresponding positive anomalies in 1000-500 hPa thickness are more widespread but largest in high latitudes. Figure 3: Surface air temperature anomalies by latitude band, offset by 1oC (figure by P. Hogarth based on CRUTEM3 and HadSST2 data). The existence of ice and snow in the Arctic enhances its sensitivity to forcing anomalies. Note that Arctic temperatures (bottom curve) exhibit larger fluctuations, as well as larger positive trends since mid-century. Extreme weather comes in many flavors. In this study we refer to events that result from persistent weather conditions, such as heat waves, cold spells, droughts, and prolonged precipitation that causes floods and snowy winters. These types of events are associated with high-amplitude patterns in 500 hPa heights that tend to move slowly and create persistent