A Compact Trace Gas Lidar for Simultaneous Measurements of Methane and Water Vapor Column Abundance

Methane is the second most important anthropogenic greenhouse gas. Understanding current global methane trends is a difficult challenge that cannot be resolved by existing measurement networks or satellite observations. Our proposed technology will directly address the objectives of NASA's Earth Science Decadal Survey which called explicitly for cost-effective global methane measurement technology and will enable global CH4 and H2O measurements with sufficient coverage, sensitivity, and precision to address pressing science questions for the carbon cycle and climate change. For this effort we propose to advance the technology readiness level for a CH4/H2O lidar operating at 1651 nm that can measure methane with very high spatial resolution and precision and extend the measurement to water vapor. Specifically we are proposing to: 1) Scale the laser transmitter energy to 300 µJ and package the transmitter for a future airborne demonstration. 2) Measure methane column abundance with a 1% precision. 3) Extend the wavelength coverage to detect water vapor. 4) Advance the technology readiness level (TRL) of our laboratory instrument from TRL 3 to TRL 6.The proposed work will commence in February 2015 and conclude three years later. Our team is uniquely qualified for this work. Over the past decade our group at Goddard Space Flight Center has built lidars for several space missions and demonstrated a strong capability for the remote measurements of several trace gases on the ground and from airborne platforms. Our group was the first to demonstrate CH4 column measurements from a high altitude aircraft. More »