ATMOSPHERIC METHANE RATIO AND ENVIRONMENTAL-CHANGES IN THE SAHARA AND SAHEL DURING THE LAST 130 KYRS

The comparison of the Vostok CH4 curve, over the last 130 ka, with the dated succession of humid/arid phases in the 6,500,000 km2 area between 13-degrees-N and 27-degrees-N, in Africa, shows that they roughly co-vary. We propose those past ecological changes in vast tropical areas as one of the factors that contributed to the global increase/decrease of the methane production.