迁站和仪器更换对阿拉山口风速资料的影响分析

Influence of Station and Instruments Change on Wind Speed Data in Alashankou

风是一个对测点环境变化较为敏感的气象要素,测站迁站、环境变化、仪器更换等因素均会导致风速序列的非均一性,从而使一地风资料缺乏真实性和可信度。阿拉山口是我国一个著名风门,并且阿拉山口站经历过多次迁站和仪器更换,因此对阿拉山口风资料的均一性检验很有必要,本文利用M-K突变检验法、标准差以及方差显著差异分析等方法对阿拉山口风速序列进行均一性检验,得出:阿拉山口站54 a平均风速序列在2004年发生突变,突变后风速大幅减小。2001年的迁站没有造成风速突变,且经过检验新、旧站风速资料可以合并统计;2004年更换自动测风仪所测风速比人工站大,与2004年后风速突然减小相反;阿拉山口站与周边对比站风速变化曲线在2004年后是反相的,分析可知风速突变的原因不是由仪器更换、气候变化直接导致,经调查分析与2004—2005年阿拉山口地区在气象站上风方大面积种植防风林带有关。

Alashankou is a famous gale gate and the station has been moved many times as well as instruments has been changed many times. To check consistency of wind data in Alashankou area is very necessary. In this article M-K mutation and standard deviation methods with significant variations analysis method on Alashankou wind data for its’ speed sequence was used. The conclusionis as follows. The variation of 54 years annual average wind speed showed catastrophe in 2004, then sharply decreased in Alashankou meteorological station. After test, it showed that the new and the old wind data can be statistically combined so that the station relocation did not cause wind speed catastrophe. The wind speed data measured by new installed automatic wind detecting instrument in 2004 was larger than the manual measurement. This increase was opposite to the sudden decrease in 2004. The variation curve of wind speed in Alashankou meteorological station was opposite to that of adjacent comparisonable station. The investigation showed the catastrophe was not directly caused by instrument replacement or climate change, it related to the large area shelter belt planted in the upwind direction of Alashankou meteorological station during 2004-2005.