Abstract:

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.

Key words: Prydz Bay, summer surface water, circumpolar deep water upwelling, dynamic height, sea ice concentration