本文選題：南海 + 熱帶氣旋��； 參考：《廣東海洋大學(xué)》2016年碩士論文

【摘要】：南海是西北太平洋最大的邊緣海,存在著豐富的熱帶氣旋現(xiàn)象。熱帶氣旋作為南海重要的物理過(guò)程,對(duì)海洋物理、化學(xué)及生態(tài)環(huán)境等各方面都有著重要影響。開(kāi)展上層海洋對(duì)于熱帶氣旋的響應(yīng)研究,對(duì)于深入了解上層海洋—低層大氣生物地球化學(xué)與物理過(guò)程耦合機(jī)制具有重要的科學(xué)意義與實(shí)際應(yīng)用價(jià)值。本文通過(guò)現(xiàn)場(chǎng)觀測(cè)數(shù)據(jù)并結(jié)合熱帶風(fēng)暴過(guò)境期間的衛(wèi)星遙感數(shù)據(jù),主要關(guān)注2005年第8號(hào)熱帶風(fēng)暴“天鷹”發(fā)生期間,南海西北部上層海洋對(duì)其的熱力學(xué)、動(dòng)力學(xué)響應(yīng)特征,得到了具有一定價(jià)值的定量結(jié)果,并對(duì)南海西北部上層海洋對(duì)熱帶氣旋的響應(yīng)機(jī)制進(jìn)行了分析。2005年7月30日,熱帶風(fēng)暴“天鷹”過(guò)境期間,由于風(fēng)攪動(dòng)引起的強(qiáng)烈混合以及水平流垂向剪切不穩(wěn)定導(dǎo)致的夾卷與抽吸,在南海西北部海域引起了很強(qiáng)的海表面溫度下降,在“天鷹”移動(dòng)軌跡右側(cè)存在最大降溫(3.6℃),并且降溫具有明顯的右偏性;熱帶風(fēng)暴在觀測(cè)站點(diǎn)處引起的海表面降溫約為2℃。由觀測(cè)站點(diǎn)溫度剖面發(fā)現(xiàn),混合層加深10-20 m,海洋內(nèi)部不同深處對(duì)熱帶風(fēng)暴“天鷹”的響應(yīng)存在不同,上混合層處于降溫狀態(tài),而溫躍層以下至70 m水深則處于增溫狀態(tài)。熱帶風(fēng)暴過(guò)境期間,在低溫區(qū)中存在著強(qiáng)烈的上升流,其最大抽吸速度大于1.6×10-4 m/s。通過(guò)混合層內(nèi)的熱收支,分別計(jì)算出各項(xiàng)因素的貢獻(xiàn),結(jié)果表明垂向混合起主導(dǎo)作用,約占70%,而�？寺梦饔玫认鄬�(duì)較弱。熱帶風(fēng)暴過(guò)后,由熱帶風(fēng)暴引起的近慣性振蕩,周期為35 h,略小于當(dāng)?shù)氐膽T性振蕩周期,最大流速約為0.2 m/s存在于混合層,且近慣性波動(dòng)向下傳播;流速隨水深加深而減弱,上混合層內(nèi)與深層流速呈反方向。利用現(xiàn)場(chǎng)觀測(cè)數(shù)據(jù)進(jìn)行計(jì)算分析后,發(fā)現(xiàn)熱帶風(fēng)暴“天鷹”過(guò)境后上層海洋混合率平均增強(qiáng)了3倍以上。
[Abstract]:The South China Sea is the largest marginal sea in the Northwest Pacific Ocean, and there are abundant tropical cyclones. As an important physical process in the South China Sea, tropical cyclones play an important role in marine physics, chemistry and ecological environment. The research on the response of the upper ocean to tropical cyclones is of great scientific significance and practical value in understanding the coupling mechanism of biogeochemistry and physical processes in the upper ocean-lower atmosphere. Based on the field observation data and satellite remote sensing data during the transit of tropical storms, this paper focuses on the thermodynamic and dynamic response of the upper seas in the northwestern South China Sea during the occurrence of Tropical Storm No. 8 in 2005. Some valuable quantitative results are obtained, and the response mechanism of the upper ocean in the northwestern South China Sea to tropical cyclones is analyzed. On July 30, 2005, during the transit of Tropical Storm "Sky Eagle", Due to the strong mixing caused by wind agitation and the entrainment and suction caused by vertical shear instability of horizontal flow, strong sea surface temperature drops have been caused in the northwestern South China Sea. The maximum temperature drop (3.6 鈩，

本文編號(hào)：2086175