资源环境科技发展态势分析平台

The present study investigates relationship between interannual variations of snow cover and local surface and atmospheric variables, and the formation of interannual snow cover anomalies over the Tibetan Plateau in the cold seasons (autumn, winter, and spring). It is shown that the snow-related surface heat flux and atmospheric heat source anomalies increase from autumn to spring, whereas precipitation anomalies are most prominent in autumn. This suggests that snow cover anomalies over the central eastern Tibetan Plateau are mainly formed in autumn and their impacts are most prominent in spring. The central eastern Tibetan Plateau snow cover anomalies have high month-to-month persistence during October through April, indicative of a large contribution of persistence to snow cover anomalies in winter and spring. The Tibetan Plateau snow cover anomalies in cold seasons are influenced by large-scale atmospheric circulation anomaly pattern of different paths. In autumn, a wave pattern from the North Pacific to the Tibetan Plateau via the North Atlantic, induced by eastern North Pacific and western North Atlantic sea surface temperature anomalies, plays an important role in the formation of snow cover anomalies. In winter, a North Atlantic Oscillation related wave pattern from the North Atlantic to East Asia may contribute to snow cover anomalies. In spring, a midlatitude wave pattern originating over the western North Atlantic and propagating through the Mediterranean Sea to southern Tibetan Plateau may have a supplementary contribution to snow cover anomalies.