ANALYSIS ON THE CHARACTERISTICS OF TROPICAL CYCLONES MAKING LANDFALL ON DIFFERENT REGIONS OF CHINESE MAINLAND

The locations(longitudes and latitudes)of the tropical cyclones(TCs)making landfall on the Chinese mainland from 1949 to 2008 are investigated in detail by using ArcGis and FORTRAN routine.The southeast coastline[110 to 122°E)with most landfall TCs was selected as the key region,which was divided into 12 subsections with 1°intervals of longitude.The study period was from July to September in each year.The result showed that the average sustaining time of TCs making landfall on the subsections east of 118°E is longer than those west of 118°E.Before landfall,the averaged TC intensity in the subsections east of118°E is stronger than that west of it.After landfall,however,the difference between the west and east is not significant.The index of destructive potential for the period before/after landfall was defined as TDP1/TDP2.The maximum of TDP1/TDP2 occurred in the subsection of[119,120°E)/[110,111°E).The ENSO impact on the frequency and average location of landfall TC over the whole region at 110 to 122°E is not obvious,but the effect varies with specific subsections.There is little differences of averaged TDP1 in the subsections between different phases of ENSO events,but the averaged TDP2 is larger in the warm events than that in the cold events.The rainstorm days of each station caused by TCs in different subsections were counted respectively.The results suggested that the rainstorm days of the subsections east of 118°E are much more than those west of 118°E.The larger values are primarily distributed at the subsections of[119,120°E)and[110,111°E).

Weather Typing and Dissipation Forecast of Fog in Haizhou Bay

[ Objective] The research aimed to study weather typing and dissipation forecast of the fog in Haizhou Bay. [ Method] Based on the me- teorological observation data of three representative stations in Lianyungang, we analyzed weather situation before fog occurrence as well as the meteorological elements of coastal fog in Haizhou Bay, and established dissipation rating forecast equation of the fog. [ Result] From the surface weather chart, the fog in Haizhou Bay was divided into four types： low-pressure inverted trough type, prefrontal warm-zone type, high-pressure rear type and high-pressure bottom type. FOg formation was closely related to stratification stability, temperature, relative humidity, wind direction and wind velocity. By using multiple linear regression method, dissipation rating prediction equation of the fog was established. Via test, prediction was correct basically, and it reached 77% that forecast rating error was below level 0.5.[Conclusion] The research could provide favorable reference for forecast and warninq of the fo_q in Haizhou Bay.