The French-German Climate Monitoring Initiative on Global Observations of Atmospheric Methane

Abstract

Knowledge of concentrations and fluxes of the most important long-lived greenhouse carbon dioxide (CO2) and methane (CH4) is a key element of climate change research. We report on the status of the French-German Climate Monitoring Initiative which aims on global observations of atmospheric methane. This mission which has recently been selected for joint Phase0/A studies at CNES and DLR is intended to improve our understanding of the Global Methane Cycle and the exploration of the nature of the processes which govern the exchange of methane between atmosphere and biosphere. As a novel feature, the observational instrument of this mission will be an Integrated Path Differential-Absorption (IPDA) lidar system embarked on the French spacecraft MYRIADE for the measurement of the column-weighted dry-air mixing ratio of CH4. This data will be provided by the lidar technique with no bias due to particles scattering in the light path and can directly be used as input for flux inversion calculation. Other geophysical quantities which can be derived from the measurements comprise information on vegetation height, cloud layers, and surface retro-reflectance.