{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,8]],"date-time":"2025-11-08T22:13:28Z","timestamp":1762640008432,"version":"build-2065373602"},"reference-count":57,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,11,25]],"date-time":"2020-11-25T00:00:00Z","timestamp":1606262400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["820852","731070"],"award-info":[{"award-number":["820852","731070"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"ESA project VISTA","award":["4000128399\/19\/I-DT"],"award-info":[{"award-number":["4000128399\/19\/I-DT"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Volcanic emissions are a well-known hazard that can have serious impacts on local populations and aviation operations. Whereas several remote sensing observations detect high-intensity explosive eruptions, few studies focus on low intensity and long-lasting volcanic emissions. In this work, we have managed to fully characterize those events by analyzing the volcanic plume produced on the last day of the 2018 Christmas eruption at Mt. Etna, in Italy. We combined data from a visible calibrated camera, a multi-wavelength elastic\/Raman Lidar system, from SEVIRI (EUMETSAT-MSG) and MODIS (NASA-Terra\/Aqua) satellites and, for the first time, data from an automatic sun-photometer of the aerosol robotic network (AERONET). Results show that the volcanic plume height, ranging between 4.5 and 6 km at the source, decreased by about 0.5 km after 25 km. Moreover, the volcanic plume was detectable by the satellites up to a distance of about 400 km and contained very fine particles with a mean effective radius of about 7 \u00b5m. In some time intervals, volcanic ash mass concentration values were around the aviation safety thresholds of 2 \u00d7 10\u22123 g m\u22123. Of note, Lidar observations show two main stratifications of about 0.25 km, which were not observed at the volcanic source. The presence of the double stratification could have important implications on satellite retrievals, which usually consider only one plume layer. This work gives new details on the main features of volcanic plumes produced during low intensity and long-lasting volcanic plume emissions.<\/jats:p>","DOI":"10.3390\/rs12233866","type":"journal-article","created":{"date-parts":[[2020,11,25]],"date-time":"2020-11-25T21:55:06Z","timestamp":1606341306000},"page":"3866","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Multi-Sensor Analysis of a Weak and Long-Lasting Volcanic Plume Emission"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8704-8629","authenticated-orcid":false,"given":"Simona","family":"Scollo","sequence":"first","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, Piazza Roma 2, 95125 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4996-7648","authenticated-orcid":false,"given":"Antonella","family":"Boselli","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, Istituto di Metodologie per l\u2019Analisi Ambientale, CNR-IMAA, 85050 Tito Scalo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9432-3246","authenticated-orcid":false,"given":"Stefano","family":"Corradini","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Nazionale Terremoti, via di Vigna Murata 605, 00143 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0040-5011","authenticated-orcid":false,"given":"Giuseppe","family":"Leto","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Astrofisica\u2014Osservatorio Astrofisico di Catania, 95123 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lorenzo","family":"Guerrieri","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Nazionale Terremoti, via di Vigna Murata 605, 00143 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6910-8800","authenticated-orcid":false,"given":"Luca","family":"Merucci","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Nazionale Terremoti, via di Vigna Murata 605, 00143 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5593-1775","authenticated-orcid":false,"given":"Michele","family":"Prestifilippo","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, Piazza Roma 2, 95125 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6997-0887","authenticated-orcid":false,"given":"Ricardo Zanmar","family":"Sanchez","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Astrofisica\u2014Osservatorio Astrofisico di Catania, 95123 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8836-9563","authenticated-orcid":false,"given":"Alessia","family":"Sannino","sequence":"additional","affiliation":[{"name":"Dipartimento di Fisica\u2014Universit\u00e0 degli studi Napoli \u201cFederico II\u201d, 80126 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5375-1738","authenticated-orcid":false,"given":"Dario","family":"Stelitano","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Nazionale Terremoti, via di Vigna Murata 605, 00143 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"732","DOI":"10.1007\/s00445-005-0412-z","article-title":"Types of eruptions of Etna volcano AD 1670\u20132003: Implications for short-term eruptive behaviour","volume":"67","author":"Branca","year":"2005","journal-title":"Bull. Volcanol."},{"key":"ref_2","first-page":"464","article-title":"Structural analysis of the eruptive fissures at Mount Etna (Italy)","volume":"54","author":"Mazzarini","year":"2011","journal-title":"Ann. Geophys."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"8009","DOI":"10.1029\/2019GL083120","article-title":"An integrated geophysical approach to track magma intrusion: The 2018 Christmas Eve eruption at Mount Etna","volume":"46","author":"Sciotto","year":"2019","journal-title":"Geophys. Res. Lett."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1111\/ter.12403","article-title":"Large dyke intrusion and small eruption: The December 24, 2018 Mt. Etna eruption imaged by Sentinel-1 data","volume":"31","author":"Bonforte","year":"2019","journal-title":"Terra Nova"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Calvari, S., Bilotta, G., Bonaccorso, A., Caltabiano, T., Cappello, A., Corradino, C., del Negro, C., Ganci, G., Neri, M., and Pecora, E. (2020). The VEI 2 Christmas 2018 Etna eruption: A small but intense eruptive event or the starting phase of a larger one?. Remote Sens., 12.","DOI":"10.5194\/egusphere-egu2020-9120"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Laiolo, M., Ripepe, M., Cigolini, C., Coppola, D., della Schiava, M., Genco, R., Innocenti, L., Lacanna, G., Marchetti, E., and Massimetti, F. (2019). Space- and ground-based geophysical data tracking of magma migration in shallow feeding system of Mount Etna volcano. Remote Sens., 11.","DOI":"10.3390\/rs11101182"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"448","DOI":"10.3934\/geosci.2019.3.448","article-title":"Volcanic risk and the role of the media. A case study in the Etna area","volume":"5","author":"Mercatanti","year":"2019","journal-title":"AIMS Geosci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1016\/j.jvolgeores.2009.01.008","article-title":"A multidisciplinary effort to assign realistic source parameters to models of volcanic ash-cloud transport and dispersion during eruptions (Book review)","volume":"186","author":"Mastin","year":"2009","journal-title":"J. Volcanol. Geotherm. Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2634","DOI":"10.1002\/2015GL063027","article-title":"Volcanic ash concentration during the 12 August 2011 Etna eruption","volume":"42","author":"Scollo","year":"2015","journal-title":"Geophys. Res. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Webster, H.N., Devenish, B.J., Mastin, L.G., Thomson, D.J., and van Eaton, A.R. (2020). Operational modelling of umbrella cloud growth in a lagrangian volcanic ash transport and dispersion model. Atmosphere, 11.","DOI":"10.3390\/atmos11020200"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"7860","DOI":"10.1038\/ncomms8860","article-title":"Hail formation triggers rapid ash aggregation in volcanic plumes","volume":"6","author":"Mastin","year":"2015","journal-title":"Nat. Commun."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1016\/j.atmosenv.2016.10.032","article-title":"The impact of Mount Etna sulfur emissions on the atmospheric composition and aerosol properties in the central Mediterranean: A statistical analysis over the period 2000\u20132013 based on observations and Lagrangian modelling","volume":"148","author":"Sellitto","year":"2017","journal-title":"Atmos. Environ."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"7763","DOI":"10.1002\/2014GL061541","article-title":"Total volcanic stratospheric aerosol optical depths and implications for global climate change","volume":"41","author":"Ridley","year":"2014","journal-title":"Geophys. Res. Lett."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"3705","DOI":"10.5194\/acp-13-3705-2013","article-title":"Detection and characterization of volcanic ash plumes over Lille during the Eyjafjallaj\u00f6kull eruption","volume":"13","author":"Mortier","year":"2013","journal-title":"Atmos. Chem. Phys."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s41598-020-69976-y","article-title":"Magma fragmentation and particle size distributions in low intensity mafic explosions: The July\/August 2015 Piton de la Fournaise eruption","volume":"10","author":"Edwards","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"29","DOI":"10.5194\/nhess-16-29-2016","article-title":"PM10 measurements in urban settlements after lava fountain episodes at Mt. Etna, Italy: Pilot test to assess volcanic ash hazard to human health","volume":"16","author":"Andronico","year":"2016","journal-title":"Nat. Hazards Earth Syst. Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"B08206\u2013n\/a","DOI":"10.1029\/2007JB005328","article-title":"Textural and geophysical characterization of explosive basaltic activity at Villarrica volcano","volume":"113","author":"Gurioli","year":"2008","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1016\/j.jvolgeores.2016.01.009","article-title":"Near-source Doppler radar monitoring of tephra plumes at Etna","volume":"312","author":"Donnadieu","year":"2016","journal-title":"J. Volcanol. Geotherm. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2383","DOI":"10.1007\/s00445-012-0669-y","article-title":"Monitoring Etna volcanic plumes using a scanning LiDAR","volume":"74","author":"Scollo","year":"2012","journal-title":"Bull. Volcanol."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Scollo, S., Prestifilippo, M., Pecora, E., Corradini, S., Merucci, L., Spata, G., and Coltelli, M. (2014). Eruption column height estimation of the 2011\u20132013 Etna lava fountains. Ann. Geophys., 57.","DOI":"10.4401\/ag-6396"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Corradini, S., Montopoli, M., Guerrieri, L., Ricci, M., Scollo, S., Merucci, L., Marzano, F., Pugnaghi, S., Prestifilippo, M., and Ventress, L. (2016). A multi-sensor approach for volcanic ash cloud retrieval and eruption characterization: The 23 November 2013 Etna lava fountain. Remote Sens., 8.","DOI":"10.3390\/rs8010058"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Corradini, S., Guerrieri, L., Lombardo, V., Merucci, L., Musacchio, M., Prestifilippo, M., Scollo, S., Silvestri, M., Spata, G., and Stelitano, D. (2018). Proximal monitoring of the 2011\u20132015 Etna lava fountains using MSG-SEVIRI data. Geosciences, 8.","DOI":"10.3390\/geosciences8040140"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Scollo, S., Prestifilippo, M., Bonadonna, C., Cioni, R., Corradini, S., Degruyter, W., Rossi, E., Silvestri, M., Biale, E., and Carparelli, G. (2019). Near-real-time tephra fallout assessment at Mt. Etna, Italy. Remote Sens., 11.","DOI":"10.3390\/rs11242987"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Corradini, S., Guerrieri, L., Stelitano, D., Salerno, G., Scollo, S., Merucci, L., Prestifilippo, M., Musacchio, M., Silvestri, M., and Lombardo, V. (2020). Near real-time monitoring of the Christmas 2018 Etna eruption using SEVIRI and products validation. Remote Sens., 12.","DOI":"10.3390\/rs12081336"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Boselli, A., Scollo, S., Leto, G., Sanchez, R.Z., Sannino, A., Wang, X., Coltelli, M., and Spinelli, N. (2018). First volcanic plume measurements by an elastic\/raman lidar close to the Etna summit craters. Front. Earth Sci., 6.","DOI":"10.3389\/feart.2018.00125"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1007\/BF00348608","article-title":"Combined raman elastic-backscatter LIDAR for vertical profiling of moisture, aerosol extinction, backscatter, and LIDAR ratio","volume":"55","author":"Ansmann","year":"1992","journal-title":"Appl. Phys. B"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"746","DOI":"10.1364\/OL.15.000746","article-title":"Measurement of atmospheric aerosol extinction profiles with a Raman lidar","volume":"15","author":"Ansmann","year":"1990","journal-title":"Opt. Lett."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1364\/AO.20.000211","article-title":"Stable analytical inversion solution for processing lidar returns","volume":"20","author":"Klett","year":"1981","journal-title":"Appl. Opt."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"652","DOI":"10.1364\/AO.23.000652","article-title":"Analysis of atmospheric lidar observations: Some comments","volume":"23","author":"Fernald","year":"1984","journal-title":"Appl. Opt."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1364\/OE.7.000427","article-title":"Polarization lidar: Correction of instrumental effects","volume":"7","author":"Biele","year":"2000","journal-title":"Opt. Express"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1111\/j.1600-0889.2008.00396.x","article-title":"Depolarization ratio profiling at several wavelengths in pure Saharan dust during SAMUM 2006","volume":"61","author":"Freudenthaler","year":"2017","journal-title":"Tellus Ser. B Chem. Phys. Meteorol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"D00U02","DOI":"10.1029\/2010JD015567","article-title":"Ash and fine-mode particle mass profiles from EARLINET-AERONET observations over central Europe after the eruptions of the Eyjafjallaj\u00f6kull volcano in 2010","volume":"116","author":"Ansmann","year":"2011","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1016\/j.atmosenv.2012.08.015","article-title":"Lidar depolarization measurement of fresh volcanic ash from Mt. Etna, Italy","volume":"62","author":"Pisani","year":"2012","journal-title":"Atmos. Environ."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"5824","DOI":"10.1109\/TGRS.2018.2826839","article-title":"Maximum-likelihood retrieval of volcanic ash concentration and particle size from ground-based scanning lidar","volume":"56","author":"Mereu","year":"2018","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/j.jvolgeores.2014.12.016","article-title":"Evolution of the 2011 Mt. Etna ash and SO2 lava fountain episodes using SEVIRI data and VPR retrieval approach","volume":"291","author":"Guerrieri","year":"2015","journal-title":"J. Volcanol. Geotherm. Res."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"3053","DOI":"10.5194\/amt-9-3053-2016","article-title":"Real time retrieval of volcanic cloud particles and SO2 by satellite using an improved simplified approach","volume":"9","author":"Pugnaghi","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1315","DOI":"10.5194\/amt-6-1315-2013","article-title":"A new simplified approach for simultaneous retrieval of SO2 and ash content of tropospheric volcanic clouds: An application to the Mt Etna volcano","volume":"6","author":"Pugnaghi","year":"2013","journal-title":"Atmos. Meas. Tech."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"023550","DOI":"10.1117\/1.3046674","article-title":"Mt. Etna tropospheric ash retrieval and sensitivity analysis using moderate resolution imaging spectroradiometer measurements","volume":"2","author":"Corradini","year":"2008","journal-title":"J. Appl. Remote Sens."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Corradini, S., Pugnaghi, S., Piscini, A., Guerrieri, L., Merucci, L., Picchiani, M., and Chini, M. (2015). Volcanic Ash and SO2 retrievals using synthetic MODIS TIR data: Comparison between inversion procedures and sensitivity analysis. Ann. Geophys., 57.","DOI":"10.4401\/ag-6616"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"919","DOI":"10.5194\/amt-7-919-2014","article-title":"Volcanic ash infrared signature: Porous non-spherical ash particle shapes compared to homogeneous spherical ash particles","volume":"7","author":"Kylling","year":"2014","journal-title":"Atmos. Meas. Tech."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"20673","DOI":"10.1029\/2000JD900282","article-title":"A flexible inversion algorithm for retrieval of aerosol optical properties from Sun and sky radiance measurements","volume":"105","author":"Dubovik","year":"2000","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Dubovik, O., Sinyuk, A., Lapyonok, T., Holben, B.N., Mishchenko, M., Yang, P., Eck, T.F., Volten, H., Mu\u00f1oz, O., and Veihelmann, B. (2006). Application of spheroid models to account for aerosol particle nonsphericity in remote sensing of desert dust. J. Geophys. Res. Atmos., 111.","DOI":"10.1029\/2005JD006619"},{"key":"ref_43","first-page":"D11208","article-title":"Spectral discrimination of coarse and fine mode optical depth","volume":"108","author":"Eck","year":"2003","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"2368","DOI":"10.1364\/AO.40.002368","article-title":"Modified angstr\u00f6m exponent for the characterization of submicrometer aerosols","volume":"40","author":"Dubovik","year":"2001","journal-title":"Appl. Opt."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"2059","DOI":"10.1175\/BAMS-D-14-00110.1","article-title":"NOAA\u2019S HYSPLIT atmospheric transport and dispersion modeling system","volume":"96","author":"Stein","year":"2015","journal-title":"Bull. Am. Meteorol. Soc."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s13617-017-0056-7","article-title":"Forecasting volcanic ash deposition using HYSPLIT","volume":"6","author":"Hurst","year":"2017","journal-title":"J. Appl. Volcanol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"1573","DOI":"10.5194\/nhess-9-1573-2009","article-title":"Monitoring and forecasting Etna volcanic plumes","volume":"9","author":"Scollo","year":"2009","journal-title":"Nat. Hazards Earth Syst. Sci."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1007\/s11069-009-9415-y","article-title":"Aviation hazards from volcanoes: The state of the science","volume":"51","author":"Prata","year":"2009","journal-title":"Nat. Hazards"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1007\/s13753-013-0003-0","article-title":"Volcanic ash in the atmosphere and risks for civil aviation: A study in European crisis management","volume":"4","author":"Alexander","year":"2013","journal-title":"Int. J. Disaster Risk Sci."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"9823","DOI":"10.1029\/2000JD900042","article-title":"Particle size distributions of Mount Etna\u2019s aerosol plume constrained by Sun photometry","volume":"105","author":"Watson","year":"2000","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"3561","DOI":"10.1016\/S1352-2310(01)00075-9","article-title":"Photometric observations of Mt. Etna\u2019s different aerosol plumes","volume":"35","author":"Watson","year":"2001","journal-title":"Atmos. Environ."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"1180","DOI":"10.1364\/AO.43.001180","article-title":"Inversion of multiwavelength Raman lidar data for retrieval of bimodal aerosol size distribution","volume":"43","author":"Veselovskii","year":"2004","journal-title":"Appl. Opt."},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"Western, L.M., Francis, P.N., Watson, I.M., and Mackie, S. (2016). Inferring the size distribution of volcanic ash from IASI measurements and optimal estimation. Atmos. Meas. Tech. Discuss., 1\u201325.","DOI":"10.5194\/amt-2016-92"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"10969","DOI":"10.1029\/JC088iC15p10969","article-title":"Estimating particle sizes, concentrations, and total mass of ash in volcanic clouds using weather radar","volume":"88","author":"Harris","year":"1983","journal-title":"J. Geophys. Res. Ocean."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3389\/feart.2019.00052","article-title":"Real-time geophysical monitoring of particle size distribution during volcanic explosions at Stromboli volcano (Italy)","volume":"7","author":"Pioli","year":"2019","journal-title":"Front. Earth Sci."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"12207","DOI":"10.1002\/2013JD020433","article-title":"Linking the IR transmittance to size and type of volcanic ash particles","volume":"118","author":"Scollo","year":"2013","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"B08209","DOI":"10.1029\/2004JB003515","article-title":"Modeling tephra sedimentation from a Ruapehu weak plume eruption","volume":"110","author":"Bonadonna","year":"2005","journal-title":"J. Geophys. Res. Solid Earth"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/23\/3866\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:37:21Z","timestamp":1760179041000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/23\/3866"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,11,25]]},"references-count":57,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2020,12]]}},"alternative-id":["rs12233866"],"URL":"https:\/\/doi.org\/10.3390\/rs12233866","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2020,11,25]]}}}