OBSERVATION AND INVESTIGATION OF VARIABILITIES OF BASELINE CO2 CONCENTRATION OVER WALIGUAN MOUNTAIN IN QINGHAI PROVINCE OF CHINA

In-situ measurement of atmospheric COwas made at the top of the Waliguan Mountain(36°17′N,100°54′E,3816m asl).where the air is not directly affected by the local anthropogenic and natural sources,by using a nondispersiveinfrared(NDIR)analyzer and following the procedures proposed by WMO.The COin the flask samples collected onthe mountain was also analyzed in a laboratory.The measurements uncover the daily,monthly and seasonal variabilitiesand the baseline level of the COin the air over the“clean”area of Chinese hinterland.Results suggest that theCOconcentration over the East Asia continent has evident periodical variation,similar to that of global distribution.In1992,an annual mean baseline COconcentration of 356.4 ppm over the continent was obtained.The annual mean val-ue was 357.2 ppm for 1993.Some relationships between the COconcentration at Waliguan and the weather conditions,especially,wind speed and direction are found through the observation.