OK Leland Palmer, I told you on several occasions where you tried to steer threads towards Methane that you should wait until WUWT had a thread that was relevant – here you go, have at it. – Anthony
One of the indisputable facts in the field of global climate change is that the atmospheric build-up of methane (CH4) has been, over the past few decades, occurring much more slowly than all predictions as to its behavior (Figure 1). Since methane is a particularly potent greenhouse gas (thought to have about 25 times the warming power of CO2), emissions scenarios which fail to track methane will struggle to well-replicate the total climate forcing, likely erring on the high side—and feeding too much forcing into climate models leads to too much global warming coming out of them.
Figure 1. Atmospheric methane concentrations, 1985-2008, with the IPCC methane projections overlaid (adapted from: Dlugokencky et al., 2009)
Figure 2 shows the year-over-year change in the methane concentration of the atmosphere, and indicates not only that the growth rate of methane has been declining, but also that on several occasions during the past decade or so, it has dropped to very near zero (or even below) indicating that no increase in the atmospheric methane concentration (or a even a slight decline) occurred from one year to the next.