{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:55:54Z","timestamp":1760241354378,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,18]],"date-time":"2018-01-18T00:00:00Z","timestamp":1516233600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100017325","name":"ERC","doi-asserted-by":"publisher","award":["727626","279802"],"award-info":[{"award-number":["727626","279802"]}],"id":[{"id":"10.13039\/100017325","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>CO2 is the second most abundant volatile species of degassing magma. CO2 fluxes carry information of incredible value, such as periods of volcanic unrest. Ground-based laser remote sensing is a powerful technique to measure CO2 fluxes in a spatially integrated manner, quickly and from a safe distance, but it needs accurate knowledge of the plume speed. The latter is often difficult to estimate, particularly for complex topographies. So, a supplementary or even alternative way of retrieving fluxes would be beneficial. Here, we assess Bayesian inversion as a potential technique for the case of the volcanic crater of Solfatara (Italy), a complex terrain hosting two major CO2 degassing fumarolic vents close to a steep slope. Direct integration of remotely sensed CO2 concentrations of these vents using plume speed derived from optical flow analysis yielded a flux of 717 \u00b1 121 t day\u22121, in agreement with independent measurements. The flux from Bayesian inversion based on a simple Gaussian plume model was in excellent agreement under certain conditions. In conclusion, Bayesian inversion is a promising retrieval tool for CO2 fluxes, especially in situations where plume speed estimation methods fail, e.g., optical flow for transparent plumes. The results have implications beyond volcanology, including ground-based remote sensing of greenhouse gases and verification of satellite soundings.<\/jats:p>","DOI":"10.3390\/rs10010125","type":"journal-article","created":{"date-parts":[[2018,1,18]],"date-time":"2018-01-18T12:19:48Z","timestamp":1516277988000},"page":"125","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Ground-Based Remote Sensing of Volcanic CO2 Fluxes at Solfatara (Italy)\u2014Direct Versus Inverse Bayesian Retrieval"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2988-428X","authenticated-orcid":false,"given":"Manuel","family":"Quei\u00dfer","sequence":"first","affiliation":[{"name":"School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, UK"}]},{"given":"Mike","family":"Burton","sequence":"additional","affiliation":[{"name":"School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2831-723X","authenticated-orcid":false,"given":"Domenico","family":"Granieri","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia\u2014Sezione di Pisa, Via della Faggiola, 32, 56126 Pisa, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3794-5302","authenticated-orcid":false,"given":"Matthew","family":"Varnam","sequence":"additional","affiliation":[{"name":"School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, UK"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"McGee, K., Doukas, M.P., Kessler, R., and Gerlach, T.M. 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