HR: 16:15h
AN: A34B-02 INVITED     [Abstracts]
TI: Radiative consequences of recent Arctic variability
AU: * Key, E L
EM: ekey@rsmas.miami.edu
AF: University of Miami, RSMAS, 4600 Rickenbacker Causeway MPO, Miami, FL 33149 United States
AU: Minnett, P J
EM: pminnett@rsmas.miami.edu
AF: University of Miami, RSMAS, 4600 Rickenbacker Causeway MPO, Miami, FL 33149 United States
AB: Surface cloud forcing in polar regions may either be positive, and encourage warming and ice melt, or negative, and cool or promote re-freeze. Prior to 2001, the cloud forcing calculated at the Arctic surface in polynyas and leads indicated that the clouds were preferentially scattering light, leading to a cooling or negative forcing. However, in recent years, pronounced sea ice retreat has occurred along the continental margins of the Arctic Ocean, including the Beaufort Sea. The expanding open water area has created a seasonal "mega-polynya" north of Alaska that is a source of additional moisture and cloud condensation nuclei for enhanced cloud formation. Generally, this area is characterized by mixed phase clouds, which form under specific cryospheric and atmospheric conditions. The eroding sea ice and increased turbulent heat and moisture fluxes may alter mixed phase cloud distributions, amount, and type. This has the potential to perturb regional cloud forcing in a fashion which is yet unclear. Using cloud amount, distribution, and forcing values derived from recent satellite data, we describe the interaction of an increasingly ice-free Arctic with its overlying atmosphere.
DE: 0321 Cloud/radiation interaction
DE: 0752 Polynas (4540)
DE: 0754 Leads (4540)
DE: 1637 Regional climate change
DE: 9315 Arctic region (0718, 4207)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005