关键词: 新疆, 沙尘暴, 趋势, 突变

Abstract:

The trend, periods and abrupt change of sandstorm variation and the correlations between sandstorm variation and climate change were analyzed based on annual sandstorm days of 77 stations in Xingjian from 1961 to 2005 and with methods of Mann-Kendall trend test, maximum entropy spectrum and abrupt t-test. The results indicate: ①The sandstorm frequency trend is decreased in Xingjiang since 1961, the average trends are -0.25 and -0.06 in south and north of Xinjiang respectively, the decreased trend in south of Xinjiang is stronger than that in north of Xinjiang. The centers of decreased trend locate in Pishan, Andehe and both sides of middle Tianshan Mountains; the maximum decreased trend is in 1980's. ②The years when the trend is smaller than the average are mostly in recent 20 years; The sandstorm change periods are 2.9 years and 2.8 years in south of Xinjiang and 3.4 years and 2.3 years in north of Xinjiang; the quasi-periods of 3 years is common in Xiniang. ③The correlation is negative between sandstorm and temperature, precipitation, whereas positive between sandstorm and gale, and the positive correlation is closely high. The correlation significance level is different between sandstorm and temperature, precipitation in south and north of Xinjiang. As effect of gale and precipitation abrupt in 1987 and obvious temperature change during 1980s, the sandstorm frequency variation experienced abrupt changes in 1987 both in south and north of Xinjiang.

Key words: Xinjiang, sandstorm, trend, abrupt change