Performance Assessments of High-Resolution Marine Atmospheric Boundary Layer Observations from a Ship-Deployed Small Unmanned Aerial Vehicle

The deployment of small unmanned aerial systems (UASs) from marine vessels, integrated with meteorological sensors, has the potential to fill traditionally challenging observational gaps in the maritime environment. In this work we assessed observations from an iMET-XQ2 sensor used to characterize the marine atmospheric boundary layer (MABL) during a November 2019 field effort near San Clemente Island SCI). Complex atmospheric variability in the sampling region east of SCI was evident due primarily to westerly/northwesterly winds interacting with the changing elevations of SCI. The horizontal and vertical spatiotemporal variability made comparisons of UAS observations to the more traditional weather balloon radiosonde observations (RAOB) a challenge. However, approximately co-located (spatially and temporally) RAOB-UAS observations exhibit trends that are consistent with previous UAS studies that found iMET-XQ sensor aspiration was essential for proper performance. Specifically, at least 3 m/s of flow over the sensor is recommended, either in the form of UAS ascent speed, ambient wind speeds, or from propeller wash. The increased spatial and temporal resolution of MABL observations from UAS platforms will allow for meteorological verification of the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS ^®1 ) performance as well as verification of COAMPS driven electromagnetic (EM) propagation. These efforts are essential to the continued development and improvement of the Navy’s numerical weather prediction and EM radiofrequency (RF) propagation prediction capabilities.