散射计资料对台风海平面气压场的反演和定位的新方法研究

文章首先利用QuikSCAT散射计获取的海面风场资料,利用华盛顿大学行星边界层(UWPBL)模式对台风海平面气压场进行反演(称为直接反演),并对其强度进行了分析;然后对获取的海面风场,采用变分方法对风场进行分解,分解出无旋和有旋风场,对分解出的有旋风场,再利用UWPBL模式对魔羯台风的海平面气压场进行了反演,对所得结果与通常直接反演、NCEP海平面气压场及台风报文资料进行一一对比,结果表明:新的反演定位的方法对台风海平面气压场中心气压的定位精度有了进一步的提高,此种定位的方法为散射计资料在台风中的实际应用开辟了一条新的思路.关键词：散射计风场变分方法台风海平面气压场

A new method of retrieving typhoon's sea level pressure fields and central positions from scatterometer-derived sea surface winds

First, UWPBL model(the university of washington planetary boundary layer model) is used to retrieve YaGi typhoon sea level pressure from sea surface wind data of SeaWinds which are obtained from QuikSCAT(called direct retrieving) and these strength results are analyzed. Then the variational method is used to decompose the sea surface winds field into two parts: vortex and irrotational environmental flow field, the UWPBL model is used again to retrieve YaGi typhoon sea level pressure from the vortex flow field, the results of typhoon central positions are analyzed by comparing the results with the results of direct retrieving, NCEP data and typhoon annual reports. It turns out that the accuracy of the typhoon sea level pressure central position is obviously improved. This method offers a new idea for the study of typhoon from microwave scatterometer data.