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Global increase in atmospheric methane concentrations between 1978 and 1980

1982; American Geophysical Union; Volume: 9; Issue: 4 Linguagem: Inglês

10.1029/gl009i004p00477

1944-8007

D. R. Blake, Edward W. Mayer, Stanley C. Tyler, Yoshihiro Makide, Derek C. Montague, F. S. Rowland,

Atmospheric Ozone and Climate

The concentration of methane has been measured in tropospheric air samples collected in remote locations between 55°N and 53°S during six collection periods between November 1977 and November 1980. The observed concentrations of CH 4 have increased in each of six latitude locations by an average of 0.052±0.005 ppmv between January 1978 and January 1980. This (1.4±0.2)×10 14 gram increase in the total atmospheric burden of CH 4 corresponds to 35±12% of the yearly flux of (4.0±1.3)×10 14 grams needed to maintain the CH 4 concentration in steady‐state at its recent level of about 1.6 ppmv. The 1978‐1980 excess of about 0.7×10 14 grams per year of sources over sinks for CH 4 could arise from either an increase in biogenic releases or from a decrease in the average OH radical concentration in the lower troposphere, or from both.