基于卫星高度计资料的黑潮入侵南海流径的时间变化规律研究

黑潮入侵南海对南海的温盐平衡、环流、涡旋和局地气候等具有重要作用。基于吕宋海峡处黑潮不同流径的识别方法,对1993～2021年的卫星高度计资料进行识别,获取黑潮不同流径的发生时间,探究黑潮入侵南海流径的时间变化规律。结果表明:(1)黑潮主要以流套(Looping)和分支(Leaking)两种流径入侵南海,Leaking流径发生的时长(710周)和概率(46.9%)要远高于Looping流径(时长218周,概率14.4%)。(2) Looping流径和Leaking流径均可将高温高盐的西北太平洋水带入南海,Looping流径下的平均吕宋海峡上层通量(6.3×10⁶ m³/s)略大于Leaking流径(5.6×10⁶ m³/s)Looping和Leaking流径在4×10⁶ m³/s～6×10⁶ m³/s区间发生时间最长。(3)季节变化上,Looping流径主要发生在冬季,Leaking流径在冬半年均较强,夏季二者发...

TEMPORAL VARIATION OF THE KUROSHIO INTRUSION PATH INTO THE SOUTH CHINA SEA BASED ON SATELLITE ALTIMETER DATA

The Kuroshio intrusion plays an important role in the thermohaline balance, circulation, mesoscale eddy, and local climate of the South China Sea. Based on the identification methods of different Kuroshio paths in the Luzon Strait and the altimeter data between 1993 and 2021, the occurrence time of different Kuroshio paths was identified and the temporal variation of the Kuroshio intrusion paths in the Luzon Strait was studied. Results show that (1) the Kuroshio mainly intrudes into the South China Sea in the paths of the Looping and Leaking. Leaking path occurs much longer (710 weeks) and more frequently (46.9%) than Looping paths (218 weeks, 14.4%); (2) both Looping and Leaking paths can carry warmer and saltier northwestern Pacific water into the South China Sea. In addition, the mean upper Luzon Strait flux in the Looping path is a little larger than that in the Leaking path. The Looping path and Leaking path both show longer occurrence time in the range 4×10⁶~6×10⁶ m³/s, respectively; (3) seasonally, the Looping path occurs mainly in winter and the Leaking path is strong in the whole winter half year, while both paths are weak in summer; (4) both Looping and Leaking paths have significant interannual variations. The Looping path occurred for the longest time in 1996 (up to 26 weeks), but almost disappeared in 2001; the Leaking path occurred for the longest time in 2005 (up to 40 weeks), but shortest in 2013; (5) the occurrence duration of the Looping path shows a long-term increasing trend of 0.15 weeks per year and the Leaking path shows a long-term decreasing trend of -0.17 weeks per year. The total occurrence time of Kuroshio intrusion presents a long-term decreasing trend; (6) The Looping path is modulated mainly by local wind and wind stress curl southwest of Taiwan Island at both seasonal and interannual scales, while the Leaking path is associated with the location of the North Equatorial Current Bifurcation.