| Lifetime (year) | GWP20 | GWP100 | Descriptions |
---|---|---|---|---|
AR1 | 10 | 63 | 21 | Determined GWP of CH4 by including indirect effects on stratospheric water vapor, CO2 and tropospheric ozone |
SAR | 12 | 56 | 21 | Updated estimates of atmospheric lifetimes, molecular RF factors, and representation of the carbon cycle |
TAR | 12 | 62 | 23 | Decreased RF per kg of CO2 by 12% |
AR4 | 12 | 72 | 25 | Included climate-carbon feedbacks for calculating AGWP of CO2 based on Plattner et al. (2008). Increased the direct RF of CH4 by 25% (due to tropospheric ozone) and 15% (due to stratospheric H2O vapor) |
AR5 | 12.4 | 84 (85)a | 28 (30) | Included climate-carbon feedbacks for calculating the AGWP of CO2 based on Joos et al. (2013) |
86 (87) | 34 (36) | Included climate-carbon feedbacks for calculating the AGWPs of both CO2 and CH4 |