Compact QCL spectrometer for carbon isotopologue measurements from Small UAVs

Recent work by several groups has resulted in the recognition of the potential for Arctic tundral regions to become a significant net source of carbon greenhouse gases from thawing permafrost. The Department of Energy, NASA, and NSF have launched several new programs to increase observations and incorporate findings into large scale climate models. Given the difficulty of ground-based observations in the Arctic, instrumented Unmanned Aircraft Systems (UASs) represent one means to efficiently monitor large areas. Measurement of the ratio of the concentrations of the stable isotopologues of CO2 in the atmosphere can provide new data crucial to understanding the magnitude of new emissions as a function of space and time as the Arctic responds to climate forcing. New instrumentation is required to enable routine, widespread measurements with good precision from unmanned aircraft. These new observations may have important implications for global climate change modeling and, ultimately, international energy policy making. In the Phase I program, we will develop a complete conceptual design for a flight-worthy, compact sensor with the precision and accuracy required for the target measurements and that will be deployable on a compact unmanned aircraft system like the ScanEagle. In the Phase II program, we will fabricate, test, and field demonstrate a prototype sensor. Commercial Applications and Other Benefits: The proposed airborne sensor for the stable isotopologues of CO2 will enable measurements of carbon dioxide on a wider scale and at higher frequencies than are possible now. This is especially important in monitoring climate change in the Arctic. The larger database from more frequent studies will directly benefit the goals of DoEs Terrestrial Carbon Program and the North American Carbon Program. The basic sensor platform will be adaptable to applications requiring sensitive measurement of trace gases where sensor robustness and size are critical to performance, such as monitoring networks for greenhouse gases, as well as emissions from the hydraulic fracturing industry and natural gas pipeline distribution networks.