Latitudinal differences in methane fluxes from natural wetlands

Abstract

Natural wetlands contribute a significant proportion of the total source of methane (CH₄) to the troposphere. Latitudinal differences in the global CH₄ flux exist principally because of the type and extent of wetlands and the length of their active seasons. These characteristics are determined by broad latitudinal patterns of temperature and rainfall. This discussion focuses on the direct CH₄ flux measurements made by the Atmospheric Ground Emissions (AGE) program. This is the first program to investigate CH₄ fluxes on a global scale by systematically sampling wetlands over large latitudinal gradients. The initial data have shown significant CH₄ sources in tropical and boreal regions with temperate and arctic regions contributing less to the global CH₄ budget.