西太平洋中南部冬季悬空波导统计分析及成因初探  

Preliminary investigation on the winter elevated duct over south-central western Pacific Ocean

作　　者：李晓东[1] 盛立芳[1] 邱静怡[1] 刁一娜[1] 刘珊[1] LI Xiaodong SHENG Lifang QIU Jingyi DIAO Yina LIU Shan(College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China)

机构地区：[1]中国海洋大学海洋与大气学院,山东青岛266100

出　　处：《海洋气象学报》2017年第2期51-56,共6页Journal of Marine Meteorology

摘　　要：利用2015年11月—2016年1月船载GPS探空数据和欧洲中心ERA-Interim再分析资料,对西太平洋中南部海域悬空波导现象进行了统计分析。探空资料分析表明:该区域出现悬空波导的发生概率为47%,平均高度为1 393 m,平均厚度为205 m,平均强度为11.7 M-unit,平均截止波长为2.7 m。悬空波导发生时,天气晴朗,云量较少,以积云为主。进一步分析发现5~30°N范围内悬空波导发生概率高达77%,在800 h Pa左右高度存在强悬空波导现象。ERA-Interim再分析资料表明强悬空波导出现在巨大反气旋运动区,副热带高压内部缓慢下沉引起的干燥大气与海洋边界层内湿润的、上升运动大气相遇,在800 h Pa附近形成较强的相对湿度梯度和逆温,导致强悬空波导的发生。The characteristics of elevated duct over south central region of western Pacific from November 2015 to January 2016 was analyzed by ship-based GPS sounding and ECMWF reanalysis data （ERA- Interim）. The results showed that the occurrence probability of elevated duct was 47%. The mean height, thickness, and magnitude were 1 393 m, 205 m, and 11.7 M-unit, respectively. When elevated duct occurred, the weather was fine with little cumulus. The occurrence probability of elevated duct in 5-- 30°N region was up to 77%, intense elevated duct existed at about 800 hPa. ERA-Interim reanalysis data indicated that the intense elevated duct occurred in huge anticyclones. Strong relative humidity gradient and temperature inversion, which make for the intense elevated duct, was caused by encounter of slowly sinking dry air inside the subtropical anticyclone with the wet ascending marine boundary air.

关 键 词：悬空波导 GPS探空数据 西太平洋中南部 副热带高压 

分 类 号：P401[天文地球—大气物理学与大气环境]