Abstract：The instantaneous wind direction data in Z-files from Jan.2009 to Sep.2009 in Jiangsu are analyzed and the distribution characteristics of wind direction frequency in A-files are researched.We found that the arrangement and intervals of instantaneous wind direction data are almost uniform in most stations.When the sensor is under abnormal condition,there will be an obvious regularity angle interval gap after instantaneous wind direction data being arranged.The larger angle interval gaps of wind
2010, Vol. 17 