Abstract: New GPS radiosonde system was launched to detect the vertical structure of the atmosphere around the southeast Indian Ocean fronts region during the 25th Chinese Antarctic expedition. The detailed information regarding vertical profile of wind speed and air temperature above fronts between Chinese Zhongshan Station and Frementle port was described for the first time. The research reveals that the distinct vertical structure appeared at the warm/cold side of subantarctic front between Chinese Zhongshan Station and Frementle port, the low level wind speed of warm side was stronger than the cold one, which confirmed the special atmosphere-ocean interaction at the front area in the southeast Indian Ocean region. A low-level jet was observed above the subantarctic front between Chinese Zhongshan Station and Frementle port. Vertical structure of the atmosphere around the Antarctic front is quite different compared with the subantarctic front.

Key words: subantarctic front, polar front, observation, temperature, wind speed