A comparison of AIRS, MODIS and OMI sulphur dioxide retrievals in volcanic clouds
Document Type
Article
Publication Date
9-1-2011
Abstract
Volcanic degassing is a major contributor to the global sulphur dioxide (SO 2) budget, characterized by quiescent emissions in the lower troposphere with sporadic, spatially variable explosive eruptions into the upper troposphere and lower stratosphere (UTLS). The volcanic input of SO 2 to the atmosphere can be quantified using a suite of satellite-based instruments with a range of orbits and resolutions, resulting in differing estimates of SO 2 extent and concentration from eruptions. We compare near-coincident retrievals of SO 2 from the Moderate Resolution Imaging Spectroradiometer (MODIS), Atmospheric Infrared Radiation Sounder (AIRS) and OzoneMonitoring Instrument (OMI) at four eruptive settings. The OMI instrument is the most sensitive, with the ability to detect both low and high altitude clouds, but as an ultraviolet sensor, retrievals are limited to daytime, unlike the infrared sensors. AIRS retrievals are up to an order of magnitude less sensitive than OMI, restricted to water-free clouds in the upper troposphere. MODIS has the lowest sensitivity and is therefore constrained to the largest eruptions. Total tonnages from each sensor reflect these varying sensitivities along with potential calibration discrepancies. Results suggest that by using a number of instruments in synergy a more complete method of eruption detection is achieved. © 2011 Taylor & Francis.
Publication Title
Geomatics, Natural Hazards and Risk
Recommended Citation
Thomas, H.,
Watson, I.,
Carn, S.,
Prata, A.,
&
Realmuto, V.
(2011).
A comparison of AIRS, MODIS and OMI sulphur dioxide retrievals in volcanic clouds.
Geomatics, Natural Hazards and Risk,
2(3), 217-232.
http://doi.org/10.1080/19475705.2011.564212
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/9509