摘要
利用中国"海洋一号(HY-1B)"卫星海洋水色水温扫描仪(COCTS)和美国Terra卫星中分辨率成像光谱仪(MODIS)等观测数据对2011年3月2日济州岛东南海域的冯·卡门(von Krmn)大气涡街现象进行了观测和动力分析。COCTS和MODIS观测得到大气涡街涡列距离和涡旋间距比(h/a)均值分别为0.32和0.35;在大气涡街发生海域存在低风速海面风涡旋和海面温度暖舌;济州岛的大气垂直结构存在一逆温层。利用COCTS和MODIS伪彩色合成图观测时间差异,计算得到涡旋移动速率为12.2m/s,而分别利用它们各自的几何观测参数(h/a),结合涡街动力模型计算得到涡旋移动速率分别为12.8m/s和12.3m/s。利用上述观测结果计算得到大气涡街个例的脱落频率为1.24×10-4 s-1,脱落周期为134min,其中雷诺数范围为60～75,涡街运动学黏性系数范围为2 200～2 750,弗劳德数为0.10,罗斯比数为0.43。分析结果表明中国"海洋一号"卫星数据可用于冯·卡门大气涡街等海洋大气现象的定量化研究。
von Krmn vortex streets in the southeast ocean area off the Jeju Island were observed on 2March 2011 by using the Chinese Ocean Color Temperature Scanner（COCTS）data onboard Chinese Haiyang-1（HY-1B）satellite.The dynamics of the von Krmn streets were further analyzed in conjunction with observations from Moderate Resolution Imaging Spectroradiometer（MODIS）.The averaged ratios（h/a）of the spacing of two atmospheric vortex street rows to that of individual vortex from COCTS and MODIS images are 0.32and 0.35,respectively.Low wind speed vortices near sea surface and warm SST tongue were also observed in the vortex streets area,as well as an inversion temperature layer in the vertical atmosphere.The displacement speed of the vortices,12.2m/ s,was computed from two cloud images of COCTS and MODIS in adjacent time,and the values calculated using the geometrical size（h/a）and the dynamical model for the COCTS and MODIS images are 12.8m/s and 12.3m/ s,respectively.The dynamical parameters of vortex streets were estimated including shedding rate of the atmospheric vortex 1.24×10-4 s-1,shedding period 134min,Reynolds number 60to 75,kinematic vortex viscosity 2 200to 2 750,Froude number 0.10,and Rossby number 0.43.The analyzed results in this study indicate that the Chinese HY-1Bsatellite data are useful for quantitative studies on oceanic and atmospheric processes,such as von Krmn atmospheric vortex streets.
出处
《海洋学报》
CAS
CSCD
北大核心
2013年第3期96-103,共8页
基金
国家海洋局青年海洋科学基金(2012427)
国家自然科学基金项目--面上项目(41076012)
国家自然科学基金项目--青年科学基金项目(41006112)
海洋公益性行业科研专项(201005030)
