Characterization of Fire Diurnal Cycles using GOES-R ABI Fire Observations across North and South America

Abstract:

Biomass burning plays a key role in the interaction between the atmosphere and biosphere and affects atmospheric chemistry and the carbon cycle. Fire diurnal cycle characterizes diurnal dynamics of biomass burning and reveals the daily human activity in agriculture burnings, prescribed fires, and deforestation-related burnings. More importantly, fire diurnal cycle is an essential component in estimation of biomass burning emissions and a very important part of air quality forecast models. Accurate characterization of fire diurnal cycles requires high-spatiotemporal-resolution fire observations, which is beyond the capability of polar-orbiting satellites because of their very temporally sparse observations and legacy geostationary satellites due to their coarse spatial resolution. The Advanced Baseline Imager (ABI) on board the Geostationary Operational Environmental Satellite R (GOES-R) series observes fires at an unprecedented resolution of 2 km every 10 minutes in full disk across most areas of North and South America and every 5 minutes across the conterminous United States (CONUS). This study is to investigate the land cover specific diurnal cycle of fire hotspots and fire radiative power (FRP) across North and South America using three-year fire observations from the first two GOES-R satellites-GOES-16 and GOES-17 during 2018-2020. Our preliminary results suggest that fire diurnal cycle varies with land cover types and fire activity mainly happens during daytime. However, nocturnal fire activity is very significant in the western CONUS forest fires. During a day, fire activity generally peaks between noon and early afternoon, which is approximately 1-2 hours earlier in North America than South America for the same land cover type. In South America, fire activity peaks about one hour earlier in deforestation fire dominated evergreen broadleaf forests than in other land cover types. The derived land cover specific fire diurnal cycles are expected to improve the estimation of biomass burning emissions and air quality forecast.