Central Asia is vulnerable to climate change due to its scarce water resources and fragile ecosystems. However, the limited number of meteorological observations in the region restrict the study of its climate, hydrology and ecology. In order to improve the downscaled springtime temperature in Central Asia, this study explored the impact of atmospheric and snow data assimilation on climate simulations in Central Asia based on the Weather Research and Forecast (WRF) model and the WRF Data Assimilation (DA) system. The results based on climate simulations in Central Asia during the spring of 2017 show that the WRF model surface temperature simulation has a significant cold bias in Central Asia due to underestimation of snow melt. By assimilating conventional meteorological observations, the cold bias in Central Asia was reduced. This improvement is the result of both the direct effect of the analysis increment, and feedback effects from snow and atmosphere. In addition to the assimilation of atmospheric data, snow melt in Central Asia was better simulated through the assimilation of Japan Aerospace Exploration Agency (JAXA) Satellite Monitoring for Environmental Studies (JASMES) snow cover data. This further reduced the cold bias of the springtime temperature in Central Asia. Compared with an experiment that only assimilated atmospheric observations, the experiment that assimilated both snow and atmospheric data reduced the increase in temperature from the analysis and simulated a warmer land surface. This resulted in more sensible heat flux from the surface to the atmosphere and stronger sublimation and evaporation and thus improved the simulation of soil moisture.

中亚由于其水资源稀缺和生态系统脆弱而容易受到气候变化的影响。但是，该地区气象观测的数量有限，限制了其气候，水文和生态学的研究。为了改善中亚春季的降温温度，本研究基于天气研究与预报（WRF）模型和WRF数据同化（DA）系统，探讨了大气和雪数据同化对中亚气候模拟的影响。基于2017年春季中亚气候模拟的结果表明，由于低估了融雪，WRF模型地表温度模拟在中亚具有显着的冷偏差。通过吸收常规的气象观测资料，减少了中亚的冷偏见。这种改进既是分析增量的直接影响，又是来自雪和大气的反馈影响的结果。除了吸收大气数据外，还可以通过吸收日本航空航天局（JAXA）的环境研究卫星监测（JASMES）积雪数据来更好地模拟中亚的积雪。这进一步降低了中亚春季温度的冷偏差。与仅吸收大气观测值的实验相比，吸收雪和大气数据的实验减少了分析中温度的升高，并模拟了更温暖的陆地表面。这导致从地表到大气的热通量更大，升华和蒸发更强，从而改善了土壤水分的模拟。