Global Vector Winds, Wind Turbulence, and ABL Structure from the Coherent WIND-SP Instrument Concept

NASA LaRC is developing an advanced Doppler Wind Lidar (DWL) instrument concept to meet the most recent NRC Decadal Survey call for global tropospheric winds including a focus on the atmospheric boundary layer (ABL). While significant efforts have been made to characterize the data products from an orbiting (Polar and Equatorial) DWL for use in numerical weather prediction, the ABL has not previously been a major target for the instrument and mission design.

The focus upon the ABL raises issues such as ABL depth, mixing or turbulence within the ABL, vertical position and intensity of ABL jets, as well as sea state. All of the above have been derived from measurements made with coherent airborne DWLs for many years. The challenge is to design a space based coherent DWL that can deliver useful observations of those ABL and sea surface properties.

The NASA LaRC’s WIND-SP instrument concept builds upon the successful performance of the NASA DAWN (the airborne version of the WIND-SP) during the 2017 CPEX campaign in the GoM, Caribbean and western Atlantic. This paper will provide examples of how ABL properties are derived from DAWN flights over both land and water. Particular attention will be on the derivation of turbulence and the intensity of mixing within the ABL.

In addition to illustrating how ABL properties will be derived from space-based coherent DWL measurements, the expected vertical coverage of WIND-SP instrument and performance in the presence of broken cloud coverage will be discussed using simulated observations based upon global numerical weather models.