MISR Radiance Anomalies Induced by Stratospheric Volcanic Aerosols

Date

2018-11-23

Department

Program

Citation of Original Publication

Dong L. Wu , Tao Wang , Tamás Várnai , James A. Limbacher, Ralph A. Kahn , Ghassan Taha , Jae N. Lee , Jie Gong and Tianle Yuan , MISR Radiance Anomalies Induced by Stratospheric Volcanic Aerosols, Remote Sens. 2018, 10(12), 1875; https://doi.org/10.3390/rs10121875

Rights

This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
Public Domain Mark 1.0

Abstract

The 16-year MISR monthly radiances are analyzed in this study, showing significant enhancements of anisotropic scattering at high latitudes after several major volcanic eruptions with injection heights greater than 14 km. The anomaly of deseasonalized radiance anisotropy between MISR’s DF and DA views (70.5° forward and aft) is largest in the blue band with amplitudes amounting to 5–15% of the mean radiance. The anomalous radiance anisotropy is a manifestation of the stronger forward scattering of reflected sunlight due to the direct and indirect effects of stratospheric volcanic aerosols (SVAs). The perturbations of MISR radiance anisotropy from the Kasatochi (August 2008), Sarychev (June 2009), Nabro (June 2011) and Calbuco (April 2015) eruptions are consistent with the poleward transported SVAs observed by CALIOP and OMPS-LP. In a particular scene over the Arctic Ocean, the stratospheric aerosol mid-visible optical depth can reach as high as 0.2–0.5. The enhanced global forward scattering by SVAs has important implications for the shortwave radiation budget.