Meteorological observations at Syowa Station in 2000 by the 41st Japanese Antarctic Research Expedition

This report is a collection of results on meteorological observations performed by the 41st Japanese Antarctic Research Expedition from February 1, 2000 through January 31, 2001 at Syowa Station. The measuring instruments and means of compiling statistics were almost the same as those used on the 40th Expedition. Remarkable weather phenomena during the wintering period are as follows.1) In surface weather observations, fine weather continued in March, the minimum monthly mean temperature, monthly lowest temperature, and maximum duration of monthly sunshine were recorded. On the other hand, cloudy weather continued in October, the maximum monthly mean cloud amount and the minimum duration of monthly sunshine were recorded.2) In upper air observations, heavy westerly wind blew above 50hPa compared to a normal year, in September and October.3) The large-scale ozone hole was observed, as in the previous year. The ozone hole disappeared on December 1; the recovery of the total amount of ozone was secondary earliest in the last 9 years.4) In observations using aerosol sondes, we observed variations of polar stratospheric clouds (PSCs), which are thought to be the most important cause of ozone holes formed in the springtime Antarctic lower stratosphere