Spatial-Temporal Variability in Aerosols from Multiple GEO, LEO and suborbital platforms during FIREX-AQ Field Campaign

Abstract:

The Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) experiment provided a great opportunity to characterize the retrievability and the spatial-temporal variability of smoke as observed by various remote sensing imagers. These imagers deployed and/or operational during the FIREX-AQ period and domain (August 2019 over the Western U.S) included the two Moderate resolution Imaging Spectrometers (MODIS on Terra and Aqua) and the Visible Near-Infrared Imaging Suite (VIIRS on Suomi-NPP) in Low Earth Orbit (LEO), the two Advanced Baseline Imagers (ABI on GOES-E and GOES-W) in Geostationary Orbit (GEO), as well as the enhanced-MODIS simulator (eMAS on the ER-2) in suborbital altitude. Using a consistent Dark Target (DT) retrieval algorithm on all observations, we created an aerosol dataset that spanned a range of spatial (~10 km to 500 m) and temporal (~daily to ~sub-hourly) resolutions. After generally validating each sensor’s results against the ground-based AErosol RObotic NETwork (AERONET) stationary and mobile sites observations, we inter-compared the retrievals to assess the spatial and temporal variability of smoke from the fires. We specifically focused on retrievals over the Williams Flat Fire (northeast Washington State) on August 6, 2019, thereby exploring the spatial variability within and surrounding the smoke plumes benefiting from the vast different pixel resolution among sensors. With multiple eMAS flight tracks over the same fire plume, multiple GEO images throughout the day, and near nadir observations from the LEO sensors, the various spatial-temporal sampling from these platforms have the potential to observe complex wildfire and agricultural fire smoke in synergy.