南海与西北太平洋地区夏季热带气旋潜在生成指数的改进
投稿时间: 2017-12-28  最后修改时间: 2018-04-11  点此下载全文
引用本文:
摘要点击次数: 199
全文下载次数: 
作者单位E-mail
陶丽 南京信息工程大学 taoli@nuist.edu.cn 
张艺帆 南京信息工程大学  
基金项目:国家自然科学基金项目(面上项目,重点项目,重大项目)
中文摘要:现阶段使用的热带气旋潜在生成指数(genesis potential index,GPI)在气候场的空间分布上能很好地拟合了热带气旋的生成情况,但在热带气旋的年际变化拟合上效果很差。本研究考虑了相对涡度在热带气旋年际变化拟合上的重要作用,并以此为出发点,尝试改善GPI在西北太平洋地区拟合效果。基于对1979-2011年美国联合飓风警报中心提供的热带气旋最佳路径数据和NCEP/NCAR再分析资料数据集的研究,我们将之前GPI中的绝对涡度项替换为修正过的相对涡度项。科氏力项仍然保留。我们将南海(5˚-25˚N, 100˚-120˚E)与西北太平洋地区(5˚-40˚N, 120˚-180˚E)热带气旋生成的差异性也纳入了考量,并在这两个区域分别构建GPI公式,改善了对热带气旋生成的气候分布模拟。除此之外,较之已存的GPI指数,改进后的GPI还很大程度提高了GPI对热带气旋生成年际变化的拟合效果,特别是对弱热带气旋年际变化的拟合效果有了显著提升。
中文关键词:热带气旋,年际变化,潜在生成指数,西北太平洋
 
Improvement of genesis potential index for Western North Pacific tropical cyclones
Abstract:The previous genesis potential index (GPI) can simulate well the climate distribution of tropical cyclone (TC) genesis, but with a poor simulation of interannual variation of TC genesis. Our study attempts to improve the GPI over western North Pacific by considering the important impact of relative vorticity on interannual variation of TC genesis. Based on the Best-track from Joint Typhoon Warning Center and NCEP/NCAR reanalysis data from 1979 to 2011, we substitute the absolute vorticity in previous GPI with a modified relative vorticity. The Coriolis factor is still remained. The difference of tropical cyclone formation between the South China Sea(SCS) and the West North Pacific (WNP) is also taken into account and develop the GPI for the SCS (5˚-25˚N, 100˚-120˚E) and the WNP (5˚-40˚N, 120˚-180˚E) respectively. The modified GPI improve the simulation of the climate distribution of TC genesis. Moreover, compared with the previous GPI , the modified GPI much improve the simulation of the interannual variation of TC genesis, especially weak tropical cyclones.
keywords:tropical cyclone, interannual variation, genesis potential index, Western North Pacific
查看全文  查看/发表评论  下载PDF阅读器