Remote sensing atmospheric CO2 column abundance using an airborne pulsed laser sounder at 13 km altitude

Accurate global measurements of tropospheric Carbon Dioxide abundance to the “parts per million” (ppm) level is required to better quantify processes that regulate CO₂ exchange between atmosphere, land and ocean. To measure CO₂ globally NASA has planned the ASCENDS mission, Active Sensing of CO₂ Emissions over Nights, Days and Seasons. We report on an airborne laser-based remote sensing instrument we have developed at NASA-GSFC as a candidate for the ACENDS mission. Preliminary analyses of data from initial flight testing to 13 km altitude indicates a CO₂ mixing ratio of 396 ppm from CO₂ column abundance where in situ sensors determine 390 ppm mixing ratio.