CAJ | 학술논문

利用近20年的卫星遥感海面绝对动力高度(Absolute Dynamic Topography, ADT)数据、表层流数据及Argos表面漂流浮标数据等研究了热带东印度洋表层环流的季节变化特征。分析结果显示,热带东印度洋表层环流的变化与季风演替基本同步,赤道以北海域环流季节变化特征甚为显著。与此大尺度环流年循环同步,孟加拉湾湾口环流也相应变化：湾口东部在5~9月为南向流,一直延伸至苏门答腊岛外海,其他月份,从湾口东部至整个苏门答腊岛外海(4°S以北)为北向流；湾口西部经向流的变化大体与东部相反。Argos漂流浮标轨迹进一步揭示了湾内外各季节水交换路径：西南季风期,源自阿拉伯海及印度半岛南部海域的漂流浮标主要通过西南季风漂流由湾口西侧进入湾内,湾内的漂流浮标通过湾口东侧沿着苏门答腊岛进入赤道印度洋；东北季风期,漂流浮标进出湾口的途径大体与西南季风期相反。本研究还表明,季风海流及赤道急流的纬向流速季节变化最大,而经向流速的季节方差最大的则为东印度沿岸流及拉克沙群岛高压(拉克沙群岛低压)。
이용근20년적위성요감해면절대동력고도(Absolute Dynamic Topography, ADT)수거、표층류수거급Argos표면표류부표수거등연구료열대동인도양표층배류적계절변화특정。분석결과현시,열대동인도양표층배류적변화여계풍연체기본동보,적도이북해역배류계절변화특정심위현저。여차대척도배류년순배동보,맹가랍만만구배류야상응변화：만구동부재5~9월위남향류,일직연신지소문답석도외해,기타월빈,종만구동부지정개소문답석도외해(4°S이북)위북향류；만구서부경향류적변화대체여동부상반。Argos표류부표궤적진일보게시료만내외각계절수교환로경：서남계풍기,원자아랍백해급인도반도남부해역적표류부표주요통과서남계풍표류유만구서측진입만내,만내적표류부표통과만구동측연착소문답석도진입적도인도양；동북계풍기,표류부표진출만구적도경대체여서남계풍기상반。본연구환표명,계풍해류급적도급류적위향류속계절변화최대,이경향류속적계절방차최대적칙위동인도연안류급랍극사군도고압(랍극사군도저압)。
Seasonal variation of the surface-layer circulation in the eastern tropical Indian Ocean (ETIO) is analyzed using nearly 20 years of surface absolute dynamic topography (ADT) data derived from satellite observations, ocean surface current analysis-realtime (OSCAR) data and the trajectories of Argos surface drifters. The results show that the seasonal variations of the surface circulation and the monsoons in the ETIO are almost coinstantaneous. The seasonal variations are more significant north of the equator. With this seasonal cycle of large-scale circulation, the circulation at the mouth of the Bay of Bengal changes accordingly. During May-September, the eastern mouth of the bay is dominated by the southward meridional current, which extends further southward off Sumatra, while it reverses to flow northward during the rest months. The meridional current in the western bay mouth is generally opposite to that in the east. The Argos drifting buoy trajectories further reveal that the water exchange pathways in and out the bay change seasonally. During the summer monsoon, the drifting buoys from the southern India Ocean and the Arabian Sea are mainly drifted into the bay from the west side of the bay mouth, while those from the bay are drifted out from the east side. The pathway reverses during the winter monsoon. This study also shows that the maximum variance of the zonal currents is caused by the monsoon currents including the Wyrtki Jet, while the maximum variance of the meridional currents is due to the East Indian Coastal Current (EICC) and Lakshadweep High (Lakshadweep Low).