HR: 0800h
AN: C11B-0455    [Abstracts]
TI: Estimating Melt Pond Fraction and Surface Albedo During the Melt Season Using Passive Microwave Data
AU: * Douglas, D C
EM: ddouglas@usgs.gov
AF: USGS Alaska Science Center, 3100 National Park Rd, Juneau, AK 99801, United States
AU: Eremeev, V A
EM: belchans@eimb.ru
AF: Russian Academy of Sciences, Institute of Ecology and Evolution Leninsky Prospect 33, Moscow, 119071, Russian Federation
AU: Mordvintsev, I N
EM: belchans@eimb.ru
AF: Russian Academy of Sciences, Institute of Ecology and Evolution Leninsky Prospect 33, Moscow, 119071, Russian Federation
AU: Platonov, N G
EM: belchans@eimb.ru
AF: Russian Academy of Sciences, Institute of Ecology and Evolution Leninsky Prospect 33, Moscow, 119071, Russian Federation
AB: New techniques are presented for estimating and mapping melt pond fraction and all-sky broadband surface albedo using passive microwave brightness temperatures and estimates of sea ice concentration, age, and thickness. The method is based on non-linear parameterization of NSIDC AVHRR Polar Pathfinder broadband albedo and melt pond fraction. The latter was implicitly investigated using 2D look-up tables for NSIDC AVHRR Polar Pathfinder broadband albedo and surface temperature. Methods were verified with SHEBA field data and high-resolution optical satellite imagery. Derived daily maps (1979-2006) of melt pond fraction and broadband albedo (in the NSIDC Polar stereo 25km grid) clearly illustrate the negative relationship between these two parameters. Melt pond fraction has greater interannual variability in the seasonal ice zone. During the 1990s, surface albedo (melt pond fraction) decreased (increased) in the Beaufort and Chukchi Seas and increased (decreased) in the East Siberian Sea. Duration of the melt pond period was limited by melt onset date in the spring, and freeze onset date or ice disappearance date in the end. There were indications of earlier melt onset dates in the central Arctic. The earliest melt onset dates were observed in 2005 and 2006, while freeze onset dates did not show significant trends during 1979-2006. Mean July melt pond fraction did not show a significant trend, however, surface albedo in July slightly decreased south of 80-degrees north latitude.
DE: 0748 Ponds
DE: 0758 Remote sensing
DE: 4540 Ice mechanics and air/sea/ice exchange processes (0700, 0750, 0752, 0754)
SC: Cryosphere [C]
MN: 2007 Fall Meeting