关键词: 积雪, 持续性, 青藏高原

Abstract: By using the data of daily snow depth from the month of station built to December 1999 at 72 meteorological stations over the Qinghai- Tibetan Plateau, according to the rule that the snow cover day indicates the day which the snow depth ≥0.5 cm, the monthly, the winter-spring and the annual number of snow cover days are summarized. The anomalous winter-spring snow years are determined and the persistence characters of the snow anomaly on the Qinghai-Tibetan Plateau are analyzed. It is showed that the anomalies of the winter-spring snow cover are mainly decided by the snow anomalies from November to March, and arent in accordance with the ones in May and June. The negative anomalies can persist for 4 months at least in general and more than 6 months in most years, while the positive anomalies can last for 6 months in individual year and 2～4 months in general with ending in March in general. It was hardly happened that the positive or negative anomalies of the winter-spring snow persist to May and June. The main melting season of the snow in snowy winter-spring occurs from the later of February to the early of March. The snow of the winter-spring exists mainly on some high mountains. It is showed that there are four regions of the maximal value in the distribution map of the snow cover days observed by the stations. These regions are the northern slopes of the Himalaya Mountain, the region from the west of the South Qinghai Plateau to the North Tibetan Plateau, the East Plateau Pasturing Region from the eastern slopes of the Bayan Har Mountains to the southern slopes of the Anyêmaqên Mountain, the southern slopes of the Qilian Mountains in the northeastern Qinghai Province.

Key words: snow, persistence, Qinghai-Tibetan Plateau