青藏高原春季土壤湿度对长江中下游地区初夏短期气候影响的数值模拟

An Numerical Simulation on the Effect of Spring Soil Moisture in Tibetan Plateau on Early Summer Short-term Climate over Middle and Lower Reaches of Yangtze River

为了解高原春季土壤湿度变化与中国长江中下游地区短期气候变化的关系,使用NCEP全球再分析资料,利用WRF3.4.1中尺度模式,模拟长江中下游地区的初夏降水和气温。选取青藏高原(26°N^40°N,73°E^105°E)为敏感区域,通过减少(增加)敏感区域土壤湿度原始值的50%而模式中的其他参数均保持不变,进行干、湿两组敏感性试验。结果表明:若春季高原土壤湿度偏湿,长江中下游地区初夏降水大范围减小,气温在长江中游地区升高,下游地区变化幅度不明显;反之,若春季高原土壤湿度偏干,长江中下游地区降水明显增多,气温降低。

To further understand the plateau soil moisture changes in spring and its relationship with short-term climate changes in the middle and lower reaches of Yangtze River in China, we used the NCEP reanalysis data global and simulated the early summer precipitation and the temperature in the middle and lower reaches of Yangtze River with WRF3.4.1 mesoscale model. We chose the area （ 26 ° N - 40 ° N,73 ° E - 105 °E） of the Tibet Plateau as sensitive area, by decreasing （increasing） the original soil moisture of the Tibet Plateau by 50 % while other parameters in mode remain unchangeable, conduct dry and wet condition tests. The results show that if the plateau soil moisture in the spring tends to be wet, the early summer precipitation will reduce in the middle and lower reaches of Yangtze River, while the temperature will rise up in Middle reaches of Yangtze River and it varies slightly in ower reaches of Yangtze River. Conversely, if the plateau soil moisture in the spring tends to be dry, the precipitation will increase obviously and the temperature will decline.