SCREEN ET AL: FORCING OF ARCTIC WARMING

• Main Authors: J. A. Screen, C. Deser, I. Simmonds
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Sea ice
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.384.4267; http://www.cgd.ucar.edu/cas/cdeser/Docs/submitted.screen.arctic_forcing.mar12.pdf

The Arctic is warming two to four times faster than the global average. Debate continues on the relative roles of local forcing, such as that associated with sea ice reductions, versus remote forcing in driving, or amplifying, Arctic warming. This study examines the vertical profile and seasonality of observed tropospheric warming, and addresses its causes using atmospheric general circulation model simulations. The simulations enable the isolation and quantification of the role of three forcing factors to Arctic warming: 1) observed Arctic sea ice concentration (SIC) and sea surface temperature (SST) changes; 2) observed remote SST changes; and 3) direct radiative forcing (DRF) due to observed changes in greenhouse gases, ozone, aerosols, and solar output. Local SIC and SST changes explain a large portion of the observed Arctic near-surface warming, whereas remote SST changes explain the majority of observed warming aloft. DRF has primarily contributed to