{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T22:29:47Z","timestamp":1768256987457,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2020,6,30]],"date-time":"2020-06-30T00:00:00Z","timestamp":1593475200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Airborne interferometric data, obtained from the Cirrus Coupled Cloud-Radiation Experiment (CIRCCREX) and from the PiknMix-F field campaign, are used to test the ability of a machine learning cloud identification and classification algorithm (CIC). Data comprise a set of spectral radiances measured by the Tropospheric Airborne Fourier Transform Spectrometer (TAFTS) and the Airborne Research Interferometer Evaluation System (ARIES). Co-located measurements of the two sensors allow observations of the upwelling radiance for clear and cloudy conditions across the far- and mid-infrared part of the spectrum. Theoretical sensitivity studies show that the performance of the CIC algorithm improves with cloud altitude. These tests also suggest that, for conditions encompassing those sampled by the flight campaigns, the additional information contained within the far-infrared improves the algorithm\u2019s performance compared to using mid-infrared data only. When the CIC is applied to the airborne radiance measurements, the classification performance of the algorithm is very high. However, in this case, the limited temporal and spatial variability in the measured spectra results in a less obvious advantage being apparent when using both mid- and far-infrared radiances compared to using mid-infrared information only. These results suggest that the CIC algorithm will be a useful addition to existing cloud classification tools but that further analyses of nadir radiance observations spanning the infrared and sampling a wider range of atmospheric and cloud conditions are required to fully probe its capabilities. This will be realised with the launch of the Far-infrared Outgoing Radiation Understanding and Monitoring (FORUM) mission, ESA\u2019s 9th Earth Explorer.<\/jats:p>","DOI":"10.3390\/rs12132097","type":"journal-article","created":{"date-parts":[[2020,6,30]],"date-time":"2020-06-30T09:36:04Z","timestamp":1593509764000},"page":"2097","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Cirrus Cloud Identification from Airborne Far-Infrared and Mid-Infrared Spectra"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5479-5062","authenticated-orcid":false,"given":"Davide","family":"Magurno","sequence":"first","affiliation":[{"name":"Department of Physics and Astronomy, University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0349-1488","authenticated-orcid":false,"given":"William","family":"Cossich","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy, University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9582-5029","authenticated-orcid":false,"given":"Tiziano","family":"Maestri","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy, University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Richard","family":"Bantges","sequence":"additional","affiliation":[{"name":"Physics Department, Imperial College London, London SW7 2BU, UK"},{"name":"National Centre for Earth Observation, Leicester LE1 7RH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Helen","family":"Brindley","sequence":"additional","affiliation":[{"name":"Physics Department, Imperial College London, London SW7 2BU, UK"},{"name":"National Centre for Earth Observation, Leicester LE1 7RH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stuart","family":"Fox","sequence":"additional","affiliation":[{"name":"Met Office, FitzRoy Road, Exeter EX1 3PB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chawn","family":"Harlow","sequence":"additional","affiliation":[{"name":"Met Office, FitzRoy Road, Exeter EX1 3PB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathan","family":"Murray","sequence":"additional","affiliation":[{"name":"Physics Department, Imperial College London, London SW7 2BU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juliet","family":"Pickering","sequence":"additional","affiliation":[{"name":"Physics Department, Imperial College London, London SW7 2BU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura","family":"Warwick","sequence":"additional","affiliation":[{"name":"Physics Department, Imperial College London, London SW7 2BU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3542-1337","authenticated-orcid":false,"given":"Hilke","family":"Oetjen","sequence":"additional","affiliation":[{"name":"European Space Agency, ESTEC, 2201 AZ Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"RG4004","DOI":"10.1029\/2007RG000233","article-title":"The Far-infrared Earth","volume":"46","author":"Harries","year":"2008","journal-title":"Rev. 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