This paper presents a novel global estimate of wetland methane emissions based on atmospheric inverse modeling of CH4 fluxes and observed temperature and precipitation.
Figure 1. Response of wetland CH4 emissions to climate variables. Median value of the normalized emission En as function of the precipitation P and the temperature T is shown for the five climate zones (A to E) and at global scale (F). Emissions are derived from MACC project over 2000–2012 (MACC_NOAA INV). Precipitation P and temperature T are from the CRU database. The map of climate zones and the relevant mean value of wetland CH4 flux (Fm), together with the wetland area (Aw), are dis- played. The sizes of the temperature Tc and precipitation Pc bins are set to 1°C and 1 cm/month, respectively.