Networkable Diode Laser Based Differential Absorption Lidar (DIAL) for Temperature Profiling in the Lower Troposphere

Montana State University, Bozeman MT

Investigators

Abstract

Weather forecasts, especially for short-term events, critically depend on the knowledge of the lower atmosphere temperature and moisture structure. Currently, the main method to obtain those measurement is through infrequent and sparely-situated weather balloons or high-powered laser-based systems that are impractical for long-term use. This project will build upon a series of awards that have resulted in a set of lower-power, laser-based instruments that can run unattended and retrieve water vapor in the lower atmosphere. This award will expand upon current techniques to allow for a system that can also retrieve temperature in the lower atmosphere at low-power, a capability that does not currently exist. If the work proves successful, it could have a significant impact on weather forecasting, especially for severe weather and precipitation. The project also includes a training component for the next generation of remote sensing scientists. The research team will develop and demonstrate the ability of the differential absorption lidar (DIAL) technique to profile temperature in the lower atmosphere. The DIAL technique has been successfully applied to water vapor, but additional work is required to demonstrate the capacity to retrieve temperature. The advantage that a DIAL-based instrument has over other current techniques to retrieve temperature profiles is the time and spatial resolution of the measurements and the potential for unattended, low-power operations. The long-term goal of this line of research and development is to produce networkable, low-cost, ground-based remote sensing instruments that can close the observational gaps in lower tropospheric thermodynamic profiling needed by the weather and climate communities. The main steps in the project will be to: 1) choose the appropriate oxygen absorption feature to work with, 2) build the new system using existing diode-laser-based (DLB) architecture, 3) develop the final retrieval algorithm and associated data acquisition software, 4) perform initial field testing of the instrument. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.