Methane's Solar Radiative Forcing

Methane (CH4) has significant absorption bands at wavelengths of 1.7, 2.3, 3.3 and 7.6 ?m which absorb incoming solar ‘shortwave’ (SW) radiation contribute to radiative forcing (RF). A comprehensive quantification CH4 SW RF is presented using a narrow-band transfer model calculate spatially monthly resolved estimates its impact on longwave (LW) stratospheric temperature adjusted (SARF). These new calculations include satellite measurements distribution spectrally varying surface albedo, mid-infrared by methane's band. factors substantially influence effect. For 750–1,800 ppb perturbation, the all-sky top-of-atmosphere instantaneous 0.082 W m?2; tropopause it 0.002 m?2, considerably smaller than previous estimates. Including increases SARF 0.039 m?2 (or 7%) compared LW-only SARF.