HR: 1400h
AN: A23B-07    [Abstracts]
TI: Climatology of Marine Stratocumulus Cloud Fraction in the South-East Pacific Using Surface Longwave Radiative Flux Observations
AU: Ghate, V P
EM: vghate@rsmas.miami.edu
AF: RSMAS/University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, United States
AU: Albrecht, B A
EM: balbrecht@rsmas.miami.edu
AF: RSMAS/University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, United States
AU: * Fairall, C W
EM: chris.fairall@noaa.gov
AF: NOAA-ESRL/Physical Science Division, R/PSD3, 325 Broadway, Boulder, CO 80305, United States
AU: Weller, R A
EM: rweller@whoi.edu
AF: Woods Hole Oceanographic Institute, Clark 204 A, MS#29, Woods Hole, MA 02543, United States
AB: Although marine stratocumulus cloud coverage is regarded as one of the most significant regulators of the radiation budget over the eastern subtropical oceans, it is poorly represented in global climate models. The Woods Hole Oceanographic Institute (WHOI)'s Ocean Reference Station (WORS) located at 20° S 85° W has collected observations of surface thermodynamic variables and broadband radiative fluxes continuously since October 2000. A technique to derive stratocumulus cloud fraction using the WORS observations is presented and applied to the buoy observations to give a three-year climatology (for 2001-2003). The technique uses the surface downward longwave (LW) fluxes along with the clear sky LW flux estimated from a model calibrated during five WORS maintenance cruises conducted in the region. The results are compared with the satellite derived monthly cloud fraction and the ceilometer derived zenith cloud fraction (available during the maintenance cruises). The initial results and analysis show that the technique can be effectively applied to the longer datasets and the continuous observation from the WORS. Seasonal, inter-seasonal and average diurnal variations in cloud cover are obtained for the initial three years of observations.
DE: 3309 Climatology (1616, 1620, 3305, 4215, 8408)
DE: 3310 Clouds and cloud feedbacks
DE: 3360 Remote sensing
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly