Compact Raman Lidar for Aerosol Extinction Profiling 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. As the Arctic region responds to climate forcings, monitoring how aerosol distributions respond and modify their impact on radiative transfer will also become important in refining climate models and predictions. 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 vertical profile of atmospheric aerosol optical properties can provide new data crucial to understanding climate change in the Arctic. New instrumentation is required to enable routine, widespread measurements with good precision from unmanned aircraft. These new observations will 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, eye safe lidar that will enable vertical profiling of aerosol optical extinction and scattering 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 lidar will enable measurements of aerosol optical extinction 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 measurement of aerosols where sensor robustness and size are critical to performance, such as monitoring networks for the boundary layer, as well as hazardous volcanic ash clouds.