The 23rd Conference on Hurricanes and Tropical Meteorology

5B.3
SURFACE ENERGY BUDGET AND WARM POOL RESPONSE DURING TOGA COARE

Xiaoqing Wu, NCAR, Boulder, CO; and M. W. Moncrieff

The effect of cloud systems on the air-sea interaction is one of the major uncertainties in climate system modeling due to the great uncertainty in the parameterization of subgrid scale clouds and air-sea fluxes. Cloud systems affect the surface energy budget as well as the coupling between the atmosphere and the ocean through their influence on the surface radiative, heat, moisture and momentum fluxes. In order to fully investigate the cloud-ocean as well as cloud-radiation interaction, realistic cloud-scale fields have to be observed or modeled. In this regard, the cloud-resolving modeling (CRM), which resolves cloud and mesoscale dynamics and covers large domains, has ability to simulate the long-term evolution of tropical cloud systems by incorporating the fine-scale numerical model with TOGA COARE observations. The DYNAMICALLY CONSISTENT surface radiative fluxes, heat fluxes and precipitation from the CRM provide an excellent synthetic forcing for using ocean models to study the relationships among cloud systems, surface radiative and heat fluxes, sea surface temperature (SST), and upper ocean structure.

The CRM was driven by the observed evolving large-scale forcing for temperature and moisture, evolving large-scale horizontal winds, and evolving SST over the Intensive Flux Array of TOGA COARE. The model-produced month-long surface forcing was then used to force a one-dimensional (1D) ocean model. It was shown that the 1D ocean model with a nonlocal K profile parameterization can simulate the major features of the warm pool response to the atmospheric forcing. The inclusion of advective tendencies of temperature and salt in the 1D ocean model improves the simulation of SST. Sensitivity tests were conducted to examine the effects of cloud systems on the surface energy budget and the roles of the surface radiative and heat flux, precipitation, and wind stress in the evolution of SST and upper ocean structure over the tropical western Pacific.

The 23rd Conference on Hurricanes and Tropical Meteorology