OVERVIEW and STATUS of the METHANE REMOTE SENSING LIDAR MISSION: MERLIN

The Methane Remote Sensing Lidar Mission (MERLIN) aims at global ob servations of spatial and temporal gradients of atmospheric methane (CH4) using space borne active measurements based on an Integrated Path Differential Absorption (IPDA) nadir-viewing Lidar instrument. It is a joint French and German space mission which is currently in its phase D with a planned launch date in 2027. The main scientific goal of the mission is to provide the column-integrated dry-air mixing ratio of CH4 (XCH4) for all latitudes and for all seasons of the year with very small systematic errors. These precise spaceborne data will enable to significantly improve our knowledge of CH4 sources especially in regions like the tropics and high latitudes where data is still sparse compared to other regions of the world