| 摘要: |
| 有关太平洋海洋环流，特别是对亚热带(又称副热带)、热带和赤道带环流的调查研究，近数十年来在国内、外海洋学界已蓬勃展开。其中，日本气象厅于1967年至今在137°E断面上每年进行1-2次定期海洋观测，并于1972-1979年、1987-1995年在155°E断面上每年夏季进行一次观测。根据上述经向断面观测资料，许多学者对137°E断面的海流结构，温、盐分布，水团及其变异，以及与ENSO现象的关系作了细致的分析研究(邹娥梅等，1993；顾玉荷，1996；Guan，1986；Masuzawa，1967)；关于155°E断面的研究，则着重于太平洋赤道区域海流结构和它的变异及其与ENSO现象的关系等(顾玉荷，1990；Guan，1986)。本文拟根据155°E断面1972-1979年夏季(6-7月)日本气象厅的海洋水文气象观测资料(其中1974年无资料)，分析研究该断面(北亚热带、热带和赤道带海域)的温、盐度分布特征和热、盐含量及其年际变异，并探讨其与ENSO现象之间的关系。
155°E断面北起30°N，南至11°S，自北向南横穿北亚热带、热带、赤道带和南半球热带。测站的密度以1975-1977年最密(设55个测站)，1972年和1973年次之(分别设测站33个和40个)，1978年和1979年测站稀疏，仅为15个和12个。采样深度间隔于30m以浅为10m，50-150m层间为25m，150-300m层间为50m，300-1000m层间为100m。图1为断面的位置和站位分布(5028站至5058站每相邻两站中间省略一站位)。
为了便于分析断面上各纬度带的水文特征及年际变异,将该断面自北向南划分为4个纬度带，即北亚热带(18°-30°N)、北半球热带(2°-18°N，以下简称北热带)、赤道带(2°N-2°S)和南半球热带(2°S以南，以下简称南热带)。其中北热带又划分为北赤道流区(8°-18°N)和北赤道逆流区(2°-8°N)。 |
| 关键词: 155°E断面、夏季温、盐度 |
| DOI： |
| 分类号: |
| 基金项目:中国科学院海洋研究所调查研究报告第3305号；
国家自然科学基金资助项目，49576281号。 |
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| SUMMERY BASIC CHARACTERISTICS OF TEMPERATURE AND SALINITY AT 155︒E SECTION |
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Lan Shufang
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Institute of Oceanology, Chinese Academy of Sciences
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| Abstract: |
| Hydrological and meteorological data observed along 155?E section by the R/V Ryofu Maru of JMA in the summers of 1972 to 1979, were used to analyze and study the characteristics of temperature and salinity in the south tropical, tropical, north tropical, and north subtropical sea areas at this section; the heat contents along the zonal belts; the salt contents to the north and south of the high-salinity cores and their yearly variations; and their relationship to the ENSO phenomenon.
During the ENSO events in the summers of 1972 and 1976, the following similar abnormalities in temperature and salinity characteristics occurred:
1. The isotherm within the range of depth from the lower limit of the high temperature water of the upper uniform layer to the 250m in the north tropical belt near 7?to 8?N, became intensely arched, indicating considerable upwelling of cold waters.
2. The heat contents in depth<100m water layer in the north or south tropical belt appeared lower, being a negative anomaly.
3. Occupying volume and salt content of the high-salinity cores in the North or South Pacific Ocean were rather high, being a positive anomaly. Moreover, the high salinity core in the South Pacific Ocean across the equator, might extend further north, reaching as far as 6?N.
The occurrence and cause of the mentioned abnormal phenomena are discussed in this paper. |
| Key words: 155︒E section,summers,temperature and salinity |
