Interpreting the volcanological processes of Kamchatka, based on multi-sensor satellite observations

Abstract

Volcanoes are complex environmental systems that pose challenges to scientific study, due to their inherently hazardous nature and in many cases, remote locations. Satellite-based remote sensing provides a useful tool for assessing both ongoing activity and retrospective eruptions. This paper represents an initial application of a multi-sensor approach, in part to demonstrate its strengths and limitations in a single volcanic region that is fairly well monitored in situ. We utilize data from five NASA satellite-based instruments, having up to 18 years of global observations, to conduct in-depth investigations of eight volcanoes on the Kamchatka Peninsula (Russia) that were active between 2000 and 2018. From 169 eruptive plumes observed, we performed detailed plume-dynamics analysis in eighty-two cases for which sufficiently favorable observations were obtained. Plume heights from MISR and CALIOP, microphysical particle properties (e.g. fine ash, sulfates) from MISR, thermal anomalies generated by lava features from MODIS, and sulfur dioxide (SO2) concentrations from OMI and OMPS are all considered. Evidence of eruption evolution over months-to-years was identified at Shiveluch, Kliuchevskoi, Kizimen, Karymsky, Zhupanovsky, Koryaksky and Kambalny. In cases with extensive data coverage (Kliuchevskoi, Kizimen, Karymsky and Zhupanovsky), underlying subsurface dynamics is inferred, corroborated where possible with detailed ground-based data records. The 1.1 km resolution of the particle property retrievals from the Multi-angle Imaging SpectroRadiometer (MISR) instrument capture downwind plume-particle evolution in many cases. Comparison of changes in aerosol optical depth (AOD), retrieved effective particle size (REPS) and retrieved effective particle absorption (REPA) map to six plume transport regimes, indicating varying degrees of downwind particle aggregation, deposition, and/or new particle formation. Distinct meteorological conditions are identified as likely driving these evolutionary processes, most notably the atmospheric static stability and wind shear at plume altitude. This approach can be applied to volcanic plumes globally, including those for which surface monitoring is limited or entirely absent.