| Recent years, the development of remote sensing technology provides powerfultools for snow study. In this study, based on two kinds of remote-sensing data (snowdepth of SSM/I, snow cover of NOAA/AVHRR and one kind of in situ data, thetemporal and spatial distribution and the influencing factors of snow cover in Naquregion were analyzed:1) From the last period of 1960s snow cover was reduced; but in 1980s, snowcover was increased as a whole, and from 1990s snow cover was decreased. So it is aprocess about reduce increase-reduce. We make a wavelet analysis on temporaldistributions of snow, it has mainly oscillation periods of quasi-2-3 yr. The snowheavy years are 1967/1968, 1977/1978, 1980/1981, 1982/1983, 1989/1990 and1997/1998.The snow light years are 1968/1969, 1972/1973, 1975/1976 and1983/1984. The east part of Naqu region is the primary snow cover area, and thesnow cover areas exceed 15 ten-days over every half-year, and was obviouslydistinguished from the western Naqu region. The spatial distribution of snow cover iscorrelated with longitude and latitude also.2) We selected eight important factors influencing snow cover: temperature,precipitation, sunshine time, wind velocity and so on. And calculated multiple linearregression. The result showed that the correlation coefficients between simulatedoutputs and observation data were all passed the remarkable test of 0.01.3) The effect of factors influencing snow cover is very different. The method ofprincipal component analysis is used to study the principal snow distribution factors.The result shows that the principal factors are different in different area of Naqu.4) Elevation influences the distribution of snow cover.Study the impossiblerelation between atmospheric circulations and snow anomaly in naqu. There ismarked correlation between snow anomaly and MEI (Multivariate ENSOIndex).And in snow anomalies years, the subtropical anticyclone, the trough overEurope and the ridge over Ural all shows different exposures.
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