Including a Cold Pool Representation in a Convection Parameterization and Simulating Its Impacts on the Spatial and Temporal Variability of the Precipitation in the NASA GEOS GCM

Freitas, Saulo R ; Grell, G A ; Arnold, N P ; Putman, W M

关键词: ATMOSPHERIC GENERAL CIRCULATION MODELS;    CONVECTION;    GOES 5;    PARAMETERIZATION;    PRECIPITATION (METEOROLOGY);    SIMULATION;    SPATIAL DISTRIBUTION;    TEMPORAL DISTRIBUTION;    HEAT FLUX;    STORMS (METEOROLOGY);   

RP-ID  :  GSFC-E-DAA-TN64710

学科分类：大气科学

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

We developed and implemented a simple representation of a cold pool in the Grell-Freitas (GF) convection parameterization. The cold pool parameterization is based on the observation that convective-scale downdrafts produce a local ‘deficit’ of the moist static energy (MSE). This information is advected and becoming downwind available to trigger and intensify new convection. The cold pool is dissipated by a simple exponential decay using a lifetime of a few hours, or by interacting with the underneath surface by exchanging latent and sensible heat fluxes. Preliminary results show some improvement of the simulation of the diurnal cycle of the precipitation over the land, mainly during the nighttime.