Los Gatos Research (LGR) proposes to develop highly-accurate, lightweight, low-power gas analyzers for measurements of carbon dioxide (CO2) and water vapor (H2O) aboard NASAs Sensor Integrated Environmental Remote Research Aircraft (SIERRA) unmanned aerial system (UAS). These analyzers, which will exploit both conventional mid and near-infrared tunable diode laser spectrometry and LGR's patented Off-Axis ICOS technology, will be capable of meeting the stringent weight, power, and environmental requirements for UAS deployments. At the conclusion of the Phase II effort, LGR will deliver and deploy two complete systems. The first analyzer will make extremely rapid (> 20 Hz) airborne eddy flux covariance measurements of CO2 and H2O. The second instrument will measure CO2 isotopes aboard SIERRA, allowing a better understanding of the chemistry, transport, and exchange of carbon between the atmosphere, anthropogenic sources, and natural carbon sinks and sources in the terrestrial biosphere. Airborne measurements enable regional-scale investigations of carbon sources and sinks as well as measurements where conventional tower flux deployments are infeasible. These data will complement current satellite observations by providing higher horizontal resolution and vertical profiling, enabling better quantification of carbon sources and sinks. Such deployments are critically important to NASA's Earth Science Division, because they enable more efficient and cost-effective Earth observations.