Lidar ratios of stratospheric volcanic ash and sulfate aerosols retrieved from CALIOP measurements

摘要: Abstract. We apply a two-way transmittance constraint to nighttime CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) observations of volcanic aerosol layers retrieve estimates the particulate lidar ratio (Sp) at 532 nm. This technique is applied three eruption case studies that were found have injected aerosols directly into stratosphere. Numerous permitted characterization optical and geometric properties over time period 1–2 weeks. For ash-rich produced by Puyehue-Cordon Caulle (June 2011), we obtain mean median ratios 69 ± 13 sr 67 sr, respectively. sulfate-rich Kasatochi (August 2008) Sarychev Peak 2009), means retrieved 66 ± 19 sr (median 60 sr) 63 ± 14 sr 59 sr), The 532 nm layer-integrated depolarization (δp) observed for Puyehue (δp = 0.33 ± 0.03) much larger than those 0.09 ± 0.03) 0.05 0.04) eruptions. However, observe an exponential decay (e-folding 3.6 days) in δp from 0.27 0.03. Similar decreases attenuated colour case. In general, exhibited (χ′ 0.53 ± 0.07) what was 0.35 ± 0.07) 0.32 ± 0.07) layers, indicating generally composed particles. These are particularly relevant new stratospheric subtyping classification scheme, which has been incorporated version 4 level 2 CALIPSO Infrared Pathfinder Satellite Observation) data products.