Using the monthly Qinghai-Xizang Plateau snow depth derived from satellite data,the observations of surface temperature for 101 stations in the plateau,the extended reconstructed SST in the Pacific for earlier periods and so on,this study analyzes the correlations between ENSO and snow depth averaged over the whole plateau,the eastern plateau or the western plateau and their continuity for nearly 20 years.The results are:(1) The correlations are greatly different between SST in the eastern equatorial Pacific and snow depth averaged over the eastern and western plateau.The positive correlation is over 95% confidence level between snow depth averaged over the western plateau and SST in the eastern equatorial Pacific to the east of 130°W of prior late autumn and early winter,which persists to April;however,there is no significant positive correlation in the eastern equatorial Pacific corresponding to the eastern plateau.(2) During April and May after the occurrence of El Niño,surface temperature in the eastern plateau is higher than normal greatly,and the correlation coefficients with the mean SST for early November and December in the region of Niño3 are respectively 0.44 and 0.52,which is over 95% confidence level.(3) From the mature phase of El Niño in winter and before April,the extratropical westerly jet at 200 hPa is very active,which benefits the propagation along the jet to the plateau of the Rossby waves excited by SST anomaly in the eastern equatorial Pacific in the upper troposphere and then results in the enhancement of local convective activities and increased rainfall and snowfall.With weakening of ENSO signal and the westerly jet as waveguide,the Rossby waves tend to disappear and the snow depth anomaly in the plateau caused by ENSO also becomes not important.
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