鄂尔多斯夏季降水变化及对春季青藏高原地面感热的响应

The Variation Characteristics of Summer Precipitation in Ordos and Its Response to Spring Surface Sensible Heat in Tibetan Plateau

基于 1967~2000 年 ECMWF 逐月地面感热通量再分析资料及鄂尔多斯八个气象观测站夏季降水资料,研究鄂尔多斯地区夏季降水变化特征,分析该地区夏季降水对高原春季地面感热的响应。结果表明:鄂尔多斯夏季降水由西南向东北依次增加, 年代际降水呈波动减少趋势, 年际变化具有 2~3 年和准 10 年的周期演变特征;高原春季地面感热通量存在 2~4 年和准 10 年振荡周期,总体呈减小趋势;进一步研究表明,高原春季地面感热通量与鄂尔多斯夏季降水关系密切,当高原地面感热通量呈增加趋势时,鄂尔多斯夏季降水趋于增加,当高原地面感热通量呈减小趋势时,鄂尔多斯夏季降水呈减少趋势。

Based on monthly ECMWF surface sensible heat flux reanalyzed data and summer precipitation data of eight meteorological observation stations in Ordos from 1967 to 2000, the variation of summer precipitation in Ordos and its response to summer surface sensible heat are analyzed. The results show that the summer precipitation was increased from south-west to north-east in Ordos. The trends of fluctuations decrease with inter-decadal variation of the summer precipitation that circles of 2 - 3 and 10 years are prominent. There are two circles of 2 - 4 and 10 years in the decadal variation of spring surface sensible heat flux in Tibetan Plateau and the trends of fluctuations decrease. The further research shows that summer precipitation in Ordos has a close relationship with spring surface sensible heat flux in Tibetan Plateau. Summer precipitation increased in Ordos when the spring surface sensible heat flux in Tibetan plateau showed a trend of increase, or summer precipitation decreased.