作者: David R. Doelling , Patrick Minnis , Douglas A. Spangenberg , Venkatesan Chakrapani , Ashwin Mahesh
DOI: 10.1029/2000JD900455
关键词:
摘要: Cloud radiative forcing at the top of atmosphere is derived from narrowband visible and infrared radiances NOAA-12 NOAA-14 advanced very high resolution radiometer (AVHRR) data taken over Arctic Ocean during First ISCCP Regional Experiment (FIRE ACE) spring summer 1998. Shortwave longwave fluxes (TOA) were computed using narrowband-to-broadband conversion formulae based on coincident Earth Radiation Budget (ERBE) broadband AVHRR radiances. The NOAA-12/NOAA-14 validated model calculations flux Surface Heat experiment aircraft data. TOA albedos agreed with surface- aircraft-based to within one standard deviation ±0.029 an instantaneous basis. Mean differences ranged −0.012 0.023 depending platform. AVHRR-derived differed aircraft- surface-based by −0.2 −0.3 W m−2, average, when atmospheric profiles adjusted force agreement between observed calculated downwelling fluxes. deviations less than 2%. total albedo for domain 72°N 80°N 150°W 180°W changed 0.695 in May 0.510 July, while increased 217 228 m−2. Net radiation −89 −2 m−2 same period. cloud varied −15 −31 was nearly constant ∼8 dominated effect, ranging −22 −40 July. mean are consistent previous measurements ERBE, except greater maximum ERBE values. cloud-forcing results, similar some earlier estimates, most accurate values hitherto obtained regions Arctic. When no significant melting present, clear-sky showed a diurnal variation that land under clear skies. These should be valuable understanding energy budget constraining models ocean processes