对一个西北太平洋上冷锋结构和锋生过程的分析  

Structure and Frontogenesis of a Cold Front over the Northwestern Pacific During the Period 3 to 4 January, 2003

作　　者：毕玮[1] 傅刚[1] 杨育强 郭敬天[1] 石睿[1] 

机构地区：[1]中国海洋大学海洋气象系,山东青岛266003 [2]青岛市气象局,山东青岛266003

出　　处：《中国海洋大学学报（自然科学版）》2005年第4期527-533,共7页Periodical of Ocean University of China

基　　金：国家自然科学基金项目 (41 2 750 33 ;40 2 4 0 4 2 0 564)资助

摘　　要：为做好海上危险天气系统的预报,利用GMS(GeostationaryMeteorologySatellite) 5红外卫星云图和美国国家环境预报中心NCEP(NationalCentersforEnvironmentalPrediction)的航空FNL(FinalAnalysis)资料对2 0 0 3年1月3日至4日发生在西北太平洋上的1个典型冷锋结构和相伴随的锋生过程进行了研究。卫星云图显示,该冷锋于2 0 0 3年1月3日0 0UTC形成于西北太平洋上空,与锋面相伴随的云带呈东北 西南走向,东起日本岛西南部,西至台湾岛以西。该冷锋于1月4日0 4UTC在西北太平洋上空消亡。FNL资料分析表明,在锋区内存在1个较大的水平温度梯度带,水平风切变明显。该冷锋在垂直方向上具有明显的“鼻状”结构,“鼻尖”约在90 0hPa高度上。分析发现锋生函数呈水平带状分布,其后缘基本上与海洋冷锋相重合。90 0hPa以下的低空锋区内剪切项起主要的锋生作用,85 0hPa以上的高空锋区内拉伸项起主要的锋生作用,而扭转项与锋生函数的特征一致———锋生作用在锋前最为显著。In this paper the horizontal and vertical structure of a cold front that that and frontogenesis process of a typical cold front that occurred over the Northwestern Pacific during the period 3 to 4 January 2003 are presented. Satellite images showed that this cold front formed over the Northwestern Pacific at 00 UTC 3 January 2003. The cloud band associated with the cold front was oriented in the NE-SW direction. The cold front did not dissipate over the ocean until 04 UTC 4 January. According to the FNL (Final Analysis) data, the cold front was found to have a typical horizontal and vertical structure with a maximum temperature gradient and obvious wind shear. A distinct nose-shaped vertical structure of the wind shear existed at 900hPa. It was found that the band-zone ahead of the cold front was also a zone of maximum frontogenesis. The shearing term contributed positively below 900hPa. The major contributor to the frontogenesis was the stretching term above 850hPa. The frontogenesis ahead of the frontal zone was mainly due to the twisting term.

关 键 词：冷锋 锋生函数 鼻状结构 

分 类 号：P732.7[天文地球—海洋科学]