Abstract:

The meteorological factors at Inexpressible Island in the Ross Sea, which will be the candidate site of Chinese third perennial Antarctic research station, are introduced in this study. The analysis of observations from the automatic weather station indicates that the area is dominated by winds driven by the katabatic wind in excess of 10.8 m·s–1. The main wind direction is W-NW and the maximum wind speed is in excess of 32.5 m·s–1. In 2013, the lowest wind speeds were in January, November and December(the local summer). Further examination using results from the Polar Weather Research and Forecasting(Polar-WRF) Model based on NCEP Climate Forecast System Reanalysis(CFSR) sea-ice data suggests that the physical characteristics of the katabatically driven winds can be reproduced well. The higher the resolution ratio, the better the characteristics of the wind are simulate. The strong katabatic wind at Inexpressible Island results from topographic forcing. The airstream from the Reeves Glacier is its main source. The horizontal distribution of strong winds is about 50 km. A steep hill between the altitude of 1 400 m and 300 m is the key area accelerating the air flow. Therefore, the usefulness of the wind fields of the model results is verified.

Key words: Inexpressible Island, katabatic wind, automatic weather station, Polar-WRF, numerical simulation