By using the surface sensible heat flux data of ERA-interim reanalysis,we researched the inter-annual variabilityof spring Tibetan Plateau (TP)surface sensible heat flux (TPSH)during the period of 1981 to 2010 aswell as its connection to the sea surface temperature over different oceans,and such connection may affect the precipitationof East China.The main conclusions are as follows:(1)the two main modes of TPSH inter-annual variabilityare well associated with Pacific and India Ocean sea surface temperature (SST)separately.The middle andeastern tropical Pacific SST anomaly are affected by winter (DJF)ENSO signal which can stimulate a westwardand poleward wave train to change the precipitation anomaly over the southern TP.Through this process,a zonaldipole SH distribution is formed as the first mode with a periodicity of 5 a.On the other hand,an across equatorwave train was excited by the spring India Ocean SSTA tripole pattern. It may cause the east wind anomaly overTP,weakening the Background Westerly,causing an opposite SH distribution between body region of TP and thesurrounding area with a periodicity of 5 a to 7 a.(2 )The influence of ENSO SSTA over Pacific Ocean and the SSTAtripole pattern over spring India Ocean combined with the two modes of TP spring SH to the precipitation ofEast China are synergistic and it is found that TP spring SH have greater effect to spring precipitation at middleand higher latitudes.%本文利用在青藏高原适用性较好的ERA-interim地表感热通量资料,研究了1981—2010年青藏高原春季地表感热通量的年际变率与前期不同海区海温强迫的联系,以及这种联系对我国东部降水可能造成的影响.结果表明,春季青藏高原地表感热通量的年际变化有两个主要的模态,分别与前期太平洋以及印度洋海温有密切联系.与冬季ENSO事件相应的赤道中东太平洋海温强迫可以激发一个向极向西的波列,通过改变青藏高原南侧的环流和降水异常,形成一个纬向偶极型分布的高原感热第一模态,其对应的时间序列主要表现为准5 a的振荡,与ENSO事件的周期较为吻合;而春季印度洋的三极型海温分布可以强迫出一个跨越南北半球的波列,使青藏高原主体表现为东风异常,减弱背景西风,从而形成一个青藏高原主体与周围反相关的回字形感热第二模态,其主要呈现5~7a的振荡周期.ENSO事件以及印度洋海温分布分别与青藏高原春季感热两个主模态相联系,并且冬春季海温与高原春季感热主模态对我国东部春季降水有协同影响,对于我国北方降水异常而言,高原的贡献相对海洋更重要.
展开▼
