HR: 09:45h
AN: A31D-07    [Abstracts]
TI: The warm bias in the Southeastern Pacific in the NCEP CFS model
AU: * Wang, W
EM: wanqiu.wang@noaa.gov
AF: NOAA Climate Prediction, 5200 Auth Road, RM 605, Camp Springs, MD 20746, United States
AU: Xie, P
EM: pingping.xie@noaa.gov
AF: NOAA Climate Prediction, 5200 Auth Road, RM 605, Camp Springs, MD 20746, United States
AU: Higgins, W
EM: wayne.higgins@noaa.gov
AF: NOAA Climate Prediction, 5200 Auth Road, RM 605, Camp Springs, MD 20746, United States
AU: Cronin, M
EM: Meghan.F.Cronin@noaa.gov
AF: NOAA PMEL, 7600 Sand Point Way NE, Seattle, WA 98115, United States
AU: Arkin, P
EM: parkin@essic.umd.edu
AF: Univ of MD / ESSIC, 2203 Computer and Space Sciences Bldg (#224) , College Park, MD 20742, United States
AU: Weller, R
EM: rweller@whoi.edu
AF: Woods Hole Oceanographic Institution, Clark 204A, MS#29, Woods Hole, MA 02543, United States
AB: As in many contemporary coupled atmosphere-ocean general circulation models, there exists a sea surface temperature (SST) warm bias in the Southeastern Pacific (SEP) in the National Centers for Environmental Prediction (NCEP) coupled Climate Forecast System (CFS) model. This study examines the formation of this warm bias, its association with the deficiency of model-produced stratus clouds, and its impact on the model's time-mean state and interannual variability. Questions we will address include: (1) Where does the warm bias start, how does it evolve in space, and how quickly does it develop? (2) How does the warm bias relate to the deficiency of model-produced stratus clouds, and what is the contribution of the associated excessive surface radiation fluxes? (3) What is the role of oceanic dynamics in the evolution of the warm bias? (4) What are the impacts of the warm bias on the mean state of the model and on its interannual variability? These questions are addressed based on outputs from a suite of CFS integrations, including: (a) retrospective 9-month seasonal forecasts from realistic atmospheric and oceanic initial conditions from each month of 1981-2004, (b) long-term multi-decade free simulations, (c) experimental free simulations with mean surface radiation errors over the SEP area [30°S-0°; 90°W-68°W] corrected, and (d) simulations with the uncoupled oceanic component of the CFS with and without mean surface radiation errors over the SEP area.
DE: 3339 Ocean/atmosphere interactions (0312, 4504)
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly