南极普里兹湾海域夏季表层水与绕极深层水年际变化

利用中国第27、28、29和31次南极科学考察期间在普里兹湾海域获取的水文观测数据,分析了该海域的水团分布、夏季表层水年际变化及其原因和绕极深层水涌升的年际变化特征。研究发现:第27和31航次观测到的夏季表层水的温盐范围较大;第27航次观测到的夏季表层水温度相对较高,可达1.22℃;第29航次观测期间海冰较少,夏季表层水的厚度约为50 m(73.00°E、75.50°E和67.25°S断面),第31航次观测到的夏季表层水最深达到100 m;第28和29航次观测到较为明显的绕极深层水涌升,在73.00°E断面尤为突出;观测到的绕极深层水在第28航次向上涌升到90 m,在第29航次向南延伸较远,达到67.67°S;湾内气旋性环流对绕极深层水的涌升有明显的输运作用。

The inter-annual variation of summer surface water and circumpolar deep water in Prydz Bay,Antarctic

Based on the hydrographic data obtained from four CHINARE (Chinese National Antarctic Research Expedition) cruises (27th, 28th, 29th, 31st) in Prydz Bay, we analyze the distribution of water masses, the inter-annual variation of SSW (summer surface water) and the formation mechanisms, and the inter-annual variation of the upwelling CDW (circumpolar deep water). It is found that SSW has wide ranges of temperature and salinity, especially during the cruises of 27th and 29th and higher temperature up to 1.22 ℃ in the 27th cruise. Due to less sea ice cover, the area of the SSW during the 29th cruise was much larger. While the thickness of the SSW was 50 meters (in the sections of 73°E, 75.5°E and 67.25°S) during the 29th cruise, the depth of the SSW during the 31st cruise was 100 meters. The upwelling of CDW is clearly depicted especially in the section of 73°E in the cruises of 28th and 29th. It is observed that the CDW upwells to 90 m in the cruise of 28th and extends southward to 67.67°S in the 29th cruise. Cyclonic circulation has great effect on the transportation of the upwelling of CDW in the bay.