摘要
利用NOAA最优插值逐日海表温度资料和AVISO中心的海表高度异常资料,分析了黑潮延伸体区域的海表温度锋的时空变化特征以及导致其年代际变化可能的原因。结果表明,气候平均态的黑潮延伸体区域海表温度锋位于黑潮延伸体区域北部边缘,在143°E和150°E附近存在两个弯曲,SST水平梯度最大值出现在142°E附近,强度超过4.5℃/(100 km),其后强度自西向东逐渐递减,在149°E附近又出现一个较弱的大值中心,在141~153°E范围内,海表温度锋位置的平均值为36.25°N,强度的平均值为3.22℃/(100 km)。黑潮延伸体区域的海表温度锋南北位置的季节变化很弱,而其强度的季节变化非常显著。相较于较弱的季节变化,海表温度锋位置的年际和年代际的低频变化则要显著得多,其南北变化跨度超过2°。海表温度锋强度的年际和年代际的低频变化也较强,超过4.5℃/(100 km)。黑潮延伸体区域的海表温度锋的变化与太平洋年代际振荡(PDO)以及北太平洋涡旋振荡(NPGO)存在显著的相关关系,NPGO和PDO在中东太平洋区域会强迫产生海表高度异常,随后向西传播,在约3年后到达黑潮延伸体区域,使该区域流场发生变化产生海洋热平流异常,最终导致海表温度锋强度发生变化。
By using NOAA daily Optimum Interpolation Sea Surface Temperature dataand AVISO sea surface heightanomaly data, this paper analyzes the variation of Kuroshio Extension SST front and the cause for its low-frequency variation. Result shows that the mean Kuroshio Extension SST front is adjacent to the Kuroshio Extension, with two meanders located at 143 °E and 150 °E, respectively. The maximum of the SST gradient is located near 142 °E, exceeding4.5 ℃/（100km）, and the strength of the SST front gradually decreases from west to east and has a weak maximum value center around 149 °E. Averaged over 141 - 153 °E, the mean position of the Kuroshio Extension SST front is 36.25 °N, and the mean strength is 3.22℃/（100km）. The seasonal variation of the SST front position is weak, but its strength has significantly strong seasonal variation. Compared with weak seasonal variation, the interannual to interdecadal variation of SST front position is relatively strong, which can exceed 2 ~. The strength of the Kuroshio Extension SST front also has significant interannual to interdecadal variation, which can exceed 4.5℃/ （100km）. The variation of Kuroshio Extension SST front is closely linked with the Pacific Decadal Oscillation（PDO） and North Pacific Gyre Oscillation （NPGO）, the sea surface height anomaly forced by the NPGO and PDO will propagate westward, and about 3 years later reaches the Kuroshio Extension and influences the variation of the sea surface height, and finally results in the variation of SST front strength.
作者
刘明洋
谭言科
李崇银
余沛龙
殷明
LIU Ming-yang;TAN Yan-ke;LI Chong-yin;YU Pei-long;YIN Ming(No. 91939 Troop of PLA, Jiangmen 529100, China;Institute of Meteorology and Oceanography, National University of Defense Technology, Nanjing 211101, China;State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China;No. 61936 Troop of PLA,Haikou 571199, China)
出处
《热带气象学报》
CSCD
北大核心
2017年第6期903-911,共9页
Journal of Tropical Meteorology
基金
国家"973"项目(2013CB956203)
国家自然科学基金项目(41490642
41475070)共同资助
