摘要
The Newtonian relaxation is used to assimilate data from the Second Global Soil Wetness Project (GSWP2) into the initial field for soil moisture in a regional climate model (i.e., BCC_RegCM 1.0, hereinafter called RegCM). The results show that different nudging parameters can improve the simulation of the air temperature and the precipitation to some extent in summertime season over East China. When the nudging intensity is 0.5 and nudging duration is 5 days, the result is desirable. Introducing the data assimilation of soil moisture into RegCM, the amelioration is not only in the spatial distribution pattern but also in the magnitude of the temperature and the precipitation. More specifically, the assimilation experiments have corrected the systematical cold bias of the air temperature and the precipitation on the low side, which is much closer to the observation compared with the control experiment. On the whole, the assimilation experiments shed light on the fact that the simulated bias in the original RegCM may be affected by the description of soil moisture in the land surface process. Therefore, the effect of soil moisture in RegCM should be paid more attention in the future.
The Newtonian relaxation is used to assimilate data from the Second Global Soil Wetness Project (GSWP2) into the initial field for soil moisture in a regional climate model (i.e., BCC_RegCM 1.0, hereinafter called RegCM). The results show that different nudging parameters can improve the simulation of the air temperature and the precipitation to some extent in summertime season over East China. When the nudging intensity is 0.5 and nudging duration is 5 days, the result is desirable. Introducing the data assimilation of soil moisture into RegCM, the amelioration is not only in the spatial distribution pattern but also in the magnitude of the temperature and the precipitation. More specifically, the assimilation experiments have corrected the systematical cold bias of the air temperature and the precipitation on the low side, which is much closer to the observation compared with the control experiment. On the whole, the assimilation experiments shed light on the fact that the simulated bias in the original RegCM may be affected by the description of soil moisture in the land surface process. Therefore, the effect of soil moisture in RegCM should be paid more attention in the future.
作者
HU YaMin1,2,3, DING YiHui4 & LIAO Fei2 1 Institute of Tropical and Marine Meteorology, China Meteorological Administration, Guangzhou 510080, China
2 Guangdong Climate Center, Guangzhou 510080, China
3 Chinese Academy of Meteorological Sciences, Beijing 100081, China
4 National Climate Center, China Meteorological Administration, Beijing 100081, China
基金
supported by the National Natural Science Foundation of China (Grant No. 40705026)
Guangzhou Regional Meteorological Center’s Programs for Science and Technology Development (Grant No. GRMC 2007B01)