Impacts of Land Surface Heterogeneity on Thermodynamic Variables Collected from Unmanned Aircraft Systems: Results from the 2018 LAPSE-RATE Field Campaign

In the past, it has been difficult to collect systematic thermodynamic measurements in the atmospheric boundary level (the first 1000m of the atmosphere) because meteorological towers and weather balloons are limited in their spatial and/or temporal sampling frequencies. Using sUAS (small unmanned aircraft systems), scientists are now able to capture measurements, such as temperature and humidity, at high spatial and temporal scales, providing much greater insight into atmospheric dynamics that can potentially be used to improve weather forecasting. However, we do not yet know how these fine scale variables are related to land surface heterogeneity characteristics, such as terrain and land cover. . In this study, we aim to determine how two thermodynamic variables collected via sUAS, temperature and humidity, change with respect to land cover and terrain. We captured atmospheric transects at different altitudes over differing terrain and land covers with sUAS in summer 2018 in the San Luis Valley of Colorado as part of the ISARRA LAPSE-RATE field campaign. In combination with a high-resolution digital terrain model produced from UAS imagery using the structure for motion technique and land cover variables extracted from satellite data acquired concurrently, we investigate how the atmospheric variables change with respect to varying terrain and land cover. Preliminary results indicate that both land cover, as measured through the normalized difference vegetation index (NDVI) and the ratio vegetation index (RVI) and terrain may influence these variables at small scales.