{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T13:58:33Z","timestamp":1766066313105,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2013,7,19]],"date-time":"2013-07-19T00:00:00Z","timestamp":1374192000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Detection of subsurface returns from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite were demonstrated. Despite the coarse range resolution of this aerosol lidar, evidence of subsurface scattering was observed as a delay and broadening of the cross-polarized signal relative to the co-polarized signal in the three near-surface range bins. These two effects contributed to an increased depolarization at the nominal depth of 25 m. These features were all correlated with near-surface chlorophyll concentrations. An increase in the depolarization was also seen at a depth of 50 m under certain conditions, suggesting that chlorophyll concentration at that depth could be estimated if an appropriate retrieval technique can be developed. At greater depths, the signal is dominated by the temporal response of the detectors, which was approximated by an analytical expression. The depolarization caused by aerosols in the atmosphere was calculated and eliminated as a possible artifact.<\/jats:p>","DOI":"10.3390\/rs5073457","type":"journal-article","created":{"date-parts":[[2013,7,19]],"date-time":"2013-07-19T12:12:52Z","timestamp":1374235972000},"page":"3457-3475","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["Subsurface Ocean Signals from an Orbiting Polarization Lidar"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1586-2300","authenticated-orcid":false,"given":"James","family":"Churnside","sequence":"first","affiliation":[{"name":"Earth System Research Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, CO 80305, USA"}]},{"given":"Brandi","family":"McCarty","sequence":"additional","affiliation":[{"name":"Cooperative Institute for Research in Environmental Sciences, University of Colorado, 325 Broadway, Boulder, CO 80305, USA"}]},{"given":"Xiaomei","family":"Lu","sequence":"additional","affiliation":[{"name":"Langley Research Center, National Aeronautics and Space Administration, Hampton, VA 23666, USA"}]}],"member":"1968","published-online":{"date-parts":[[2013,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1120","DOI":"10.1006\/jmsc.2002.1282","article-title":"Remote sensing of capelin and other biological features in the north Pacific using lidar and video technology","volume":"59","author":"Brown","year":"2002","journal-title":"ICES J. 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