The Response of Summer Rainfall in Tibet to Polar Vortex Index

Study the response of summer precipitation in Tibetan to polar vortex index, using singular spectrum analysis (SSA) . The result show, the positive correlation polar vortex index with summer precipitation in most area of Qinghai provinces, then negative all of Tibetan in the winter; the positive correlation polar vortex index with summer precipitation in Qinghai and Tibetan in the spring. Correlation Polar vortex index of December with summer precipitation in Tibetan of June display “+-+”from south-east to north-west of Qinghai-Xizang plateau; Correlation Polar vortex index of January with summer precipitation in Tibetan of July display“+-”from south to north; Correlation Polar vortex index of February with summer precipitation in Tibetan of August except north of Qaidam basin and west of Tibetan display negative correlation, then other area of QinghaiXizang plateau display positive correlation.