| Abstract: | The reconstruction of air trapped in ice cores provides us the most di- rect information about atmospheric CH_4 variations in the past history.Ice core records from the“Three Poles(Antarctica,Greenland and Tibetan Plateau)”re- veal the detailed fluctuations of atmospheric CH_4 concentration with time and are allowed to quantify the CH_4 differences among latitudes.These data are indis- pensably in the farther study of the relationship between greenhouse gases and climatic change,and of the past changes in terrestrial CH_4 emissions.Ice cores reconstruction indicates that atmospheric CH_4 concentration has increased quickly since industrialization,and the present day's level of atmospheric CH_4(1800 pp- by)is unprecedented during the past Glacial-Interglacial climate cycles. |
