Five-satellite-sensor study of the rapid decline of wildfire smoke in the stratosphere

Abstract. Smoke from western North American wildfires reached the stratosphere in large amounts August 2017. Limb-oriented satellite-based sensors are commonly used for studies of wildfire aerosol injected into (OMPS-LP (Ozone Mapping and Profiler Suite Limb Profiler) SAGE III/ISS (Stratospheric Aerosol Gas Experiment III on International Space Station)). We find that these methods inadequate first 1–2 months after such a strong fire event due to termination (“saturation”). The nadir-viewing lidar CALIOP (Cloud-Aerosol LIdar with Orthogonal Polarization) is less affected shorter path smoke; furthermore, it provides means develop method correct attenuation signal. After initial phase, optical depth (AOD) OMPS-LP show very good agreement above 380 K isentrope, whereas tends produce higher AOD than lowermost (LMS), probably reduced sensitivity at altitudes below 17 km. Time series attenuation-corrected stratospheric smoke an exponential decline during month fire, which coincides highly significant changes properties. verified by evolution layer composition, comparing scattering ratio (CALIOP) water vapor concentration MLS (Microwave Sounder). Initially comparable most important volcanic eruptions last 25 years. Wildfire declines much faster, 80 %–90 % removed half-life approximately 10 d. hypothesize this dramatic caused photolytic loss. This process rarely observed atmosphere. However, can be studied practically no influence wet deposition, contrast troposphere where main removal submicron particles. Despite loss, particles relevant climate.