c98.
For radiative forcing of methane, see IPCC (2007), chapter 2, p 212, table 2.14. See also p 33, table TS.2. And a 2009 study further suggests that estimates for the GWP of methane should be raised Editor’s note: When measuring mass, Fleming uses the British English term “tonne”. This is equivalent to the American English term “metric ton”, and means a mass of 1,000 kg or approximately 2204.6 pounds. Note that this is different from both the American English “ton” (aka “short ton”) of 2,000 pounds, and the British English “ton” (aka “long ton” or “imperial ton”) of 2,240 pounds. To approximately convert a mass given in tonnes to the same mass given in American English tons, multiply the figure by 1.1023. To approximately convert a mass given in tonnes to the same mass given in British English tons, multiply the figure by 0.9842. by one third to take into account the effect of methane in breaking down the airborne sulphate particles, which help to cool atmosphere as they reflect heat. See Mark Henderson, “Methane’s Impact on Global Warming Far Higher than Previously Thought”, The Times, 30 October 2009.