利用简单生物圈模式SiB2模拟锡林浩特草原地表湍流通量

Modeling of the Surface Turbulence Fluxes over a Typical Steppe Prairie in Inner Mongolia,China by Using the Simple Biosphere Model 2(SiB2)

利用简单生物圈模式SiB2模拟了2007年7月1日至9月30日期间锡林浩特草原的地表能量分配、CO2通量、地表有效辐射温度和土壤湿度。采用锡林浩特国家气候观象台野外试验基地实地测量资料确定SiB2所需要的参数和初始值后,由该资料中30min一次的太阳短波辐射、大气长波辐射、水汽压、气温、水平风速和降水驱动SiB2,最后将模拟结果与实际测量的湍流通量、CO2通量、地表有效辐射温度和土壤湿度进行了对比。结果表明:1)模式分别高估净辐射、潜热通量和土壤热量通量1.1%、10%和5%,低估感热通量6%;2)模拟的7月和8月CO2通量和观测值有较好的一致性,9月低估CO2通量14.2%;3)模式得出的地表有效辐射温度白天低估、晚上高估;4)土壤湿度模拟合理。

Surface energy distribution,CO2 flux,surface effective radiative temperature,and soil moisture over a typical steppe prairie in Inner Mongolia,China from 1 July to 30 September 2007 were simulated by using Simple Biosphere model 2（SiB2）.Based on the surface flux monitoring system data,the model was initialized and driven by using short-wave solar radiation,atmospheric long-wave radiation,vapor pressure,air temperature,wind speed,and precipitation.Then the simulated and observed turbulent flux,surface effective radiative temperature,and soil moisture were compared.The results show that：1）SiB2 overestimated net radiation,latent heat flux,and soil heat flux by 1.1%,10%,and 5%,respectively,and it underestimated sensible heat flux by 6%.2）The simulated CO2 fluxes in July and August were consistent with the observation.But the model underestimated the CO2 flux in September by 14.2%.3）Surface effective radiative temperature was underestimated（overestimated）in the day（night）.4）Soil moisture was estimated reasonably.