关键词: 沙尘暴, 时空分布, 突变, 预测模型, 河西走廊中部

Abstract: Using the sandstorm days data from 6 meteorological stations in central Hexi Corridor from 1960 to 2012, the inter-decadal, inter-annual, seasonal, monthly variation and spatial variation of the sandstorm days were analyzed. Whether there were mutations in the sandstorm sequence was tested by Mann-Kendall test. A mean generating function model for the prediction of sandstorm days in central Hexi Corridor was established based on analysis of the change rule of sandstorms. The results showed that the sandstorm days in this area presented a decline tendency at a rate of 11.75 d/10a from 1960 to 2012. It was a high frequency period of sandstorms from 1960s to the mid-1980s. It began to decline obviously during the late 1980s. The first many sandstorm days were in 1970s, second in 1960s, and it began to decline gradually from 1980s to the mid-1990s, and then it showed an ascending tendency from 1997 to 2004. The outstanding year was 2001 and a total of sandstorm weather was 21 d in this year. The sandstorm days in central Hexi Corridor had an obviously reduced mutation since 1983. There was a significant negative correlation between the annual average temperature and sandstorm days. It was the most relevant one, followed by the spring average temperature, the winter evaporation and spring evaporation. 5 meteorological stations' sandstorm days was negatively correlated with the spring average temperature, and positively correlated with the winter evaporation and spring evaporation. 3 meteorological stations' sandstorm days was negatively correlated with the winter average temperature and winter precipitation. It was predicted that the sandstorm days will be in a decreasing trend in the next 20 years in central Hexi Corridor.

Key words: sandstorm, spatiotemporal distribution, mutation, forecast model, central Hexi Corridor