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Wang Z.-W.,Changzhi Meteorological Bureau | Zhao G.-X.,Shanxi Provincial Meteorological Office | Zhang R.-T.,Changzhi Meteorological Bureau | Li H.-F.,Changzhi Meteorological Bureau | Chen Y.-B.,Changzhi Meteorological Bureau
Journal of Natural Disasters | Year: 2010

Based on the air temperature data from 11 ground meterological stations in southeast area of Shanxi Proince during 1969 -2008, and used the contrast analysis and wavelet analysis methods,the comprehensive analysis of cold wave distribution charachtristics in the province was carried out. the results indicate that ( 1 ) in southeast part of the province,the cold wave is from September to May of next year; the earliest average time appears on September 13, the latest average time is on May 18;the24h cold wave has the highest frequency in January and April, and that of 48h cold wave is in January and October,December, cold waves appears rarely in May and September; the cold wave in plane is more than in mountainous region,and in canyon is more than in the basin. (2) In the last 40years,there are 7-8 year and 14year periodic change of cold wave total times,as well the periods of end time with 10 year and start time with 7 year, moreover their 20 year period is also more obvious. (3) Along with the climate warming,cold wave times reduces, initial period delays and end period advances.

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