| A morphology-based edge detection method is used to study the sea surface temperature(SST) fronts around the Taiwan Strait.The method is based on mathematical morphology,using multi-dimension and multi-structure elements.With this strong anti-noise method,we can distinguish the large thermal fronts as well as the smaller ones.Then we used this method as well as routine method in high resolution and long time series remote sensing SST data to study the thermal fronts and their seasonal,monthly and Intra-monthly variations.Hydrologic data observed along Fujian coast are also used in this study.Followings are the major conclusions:(1) According to analysis of the remote sensing data,there are four major SST fronts in the study area,namely Taiwan Bank Front,Zhe-Min Coastal Front, Zhang-Yun Ridge Front and Kuroshio Front.(2) Affected by solar radiation and monsoon,the thermal fronts in study area have seasonal variations.The fronts in winter and spring are always stronger than those in summer and autumn,both in the SST gradient magnitude and in the frontal range.(3) The thermal fronts in this study area also have monthly variations.April or October is the transition period for SST and fronts.April is the period from the winter-half-year to the summer-half-year,when SST starts to increase but the SST fronts begin to decrease.October is the period from the summer-half-year to the winter-half-year,when SST starts to decrease but the SST fronts increase.(4) Turning of the wind direction has significant effects on SST fronts,and these effects are applied through the sea surface currents such as Zhe-Min Coastal Current and Kuroshio branch.(5) According to the sea surface temperature measured by underway observation system,Fujian coast is regarded as frequent occurrence area of SST front, because of the diluted water,upwellings in Dongshan and Pingtan,tide,and Zhe-Min Coastal Current.The frontal variations in near shore are much more acute than in the offshore regions.
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