Precise and continuous measurement of atmospheric CH_4 concentration was initiated at Syowa Station in February 1988. A diurnal variation of CH_4 concentration was not observable throughout the year, but irregular variations with periods of a few days and an amplitude of about 5ppbv at most were sometimes observed. A regular seasonal cycle of CH_4 concentration with a winter maximum and a summer minimum was clearly seen. The peak-to-peak amplitude of the averaged seasonal cycle was 30ppbv. CH_4 concentration was secularly increasing; the mean rate of the increase between 1988 and 1992 was 10.4ppbv yr^<-1>.
昭和基地における大気中のメタン濃度の連続観測
.png)
KJ00000140320
(300.62KB)
概要
