| Using hourly datas of23stations in the coastal areas of Jiangsu, included wind, pressure and temperature datas from2005to2008, improved the sea-land breeze separation technique based on monthly predecessor to the new one which is based on daily average and prove it. The result shows that the improved method can separate sea-land breeze component from large scale wind component included monsoon and daily wind parts. It can be used to establish a pure sea-land breeze data by which coastal station lacked horizontal data in monsoon region.Stat the characters of main wind direction, critical wind speed and some geographical features like the trend of coastline etc, quantized as a criterion which is applied to coastal areas of Jiangsu. Then use it to study every features included the day frequency, mean wind velocity, the strength and onset-end-duration time of sea-land breeze.The results indicated that:1) The number and frequency of sea-land day is higher in summer and autumn, lower in winter and spring.2) Sea-land breeze onset-end time is earlier in Jan than in Jul; land breeze onset time is on the contrary Spatial distribute between Jan and Jul.3) The strength of sea breeze in offshore is greater than the one inland, and it take less time from sea breeze onset to the maximum speed time in offshore station.4) The peak of sea breeze direction frequency is from17:00to20:00, and the land breeze’s is from01:00to06:00.5) The onset sea wind direction is mainly in E direction in Lian Yungang, NNE～NE in Yancheng and ENE-E in Nantong; the onset sea wind speed is mostly in the interval of2to3m/s.Further researches on influence of unban heat island on sea-land breeze, the results revealed that1) The difference is clearly only in strong heat island condition.2) Strong heat island makes the speed of sea and land breeze both increase,and the land breeze speed growth more clearly, also the land wind end time and sea wind onset-end time is in advance clearly in strong heat island condition. |
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