{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T21:08:09Z","timestamp":1766178489525,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,5]],"date-time":"2018-10-05T00:00:00Z","timestamp":1538697600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000104","name":"National Aeronautics and Space Administration","doi-asserted-by":"publisher","award":["NNX15AB11G"],"award-info":[{"award-number":["NNX15AB11G"]}],"id":[{"id":"10.13039\/100000104","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41331171"],"award-info":[{"award-number":["41331171"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chinese Scholarship Council","award":["201606040098"],"award-info":[{"award-number":["201606040098"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Earth\u2019s reflectivity is among the key parameters of climate research. National Aeronautics and Space Administration (NASA)\u2019s Earth Polychromatic Imaging Camera (EPIC) onboard National Oceanic and Atmospheric Administration (NOAA)\u2019s Deep Space Climate Observatory (DSCOVR) spacecraft provides spectral reflectance of the entire sunlit Earth in the near backscattering direction every 65 to 110 min. Unlike EPIC, sensors onboard the Earth Orbiting Satellites (EOS) sample reflectance over swaths at a specific local solar time (LST) or over a fixed area. Such intrinsic sampling limits result in an apparent Earth\u2019s reflectivity. We generated spectral reflectance over sampling areas using EPIC data. The difference between the EPIC and EOS estimates is an uncertainty in Earth\u2019s reflectivity. We developed an Earth Reflector Type Index (ERTI) to discriminate between major Earth atmosphere components: clouds, cloud-free ocean, bare and vegetated land. Temporal variations in Earth\u2019s reflectivity are mostly determined by clouds. The sampling area of EOS sensors may not be sufficient to represent cloud variability, resulting in biased estimates. Taking EPIC reflectivity as a reference, low-earth-orbiting-measurements at the sensor-specific LST tend to overestimate EPIC values by 0.8% to 8%. Biases in geostationary orbiting approximations due to a limited sampling area are between     \u2212 0.7 %     and 12%. Analyses of ERTI-based Earth component reflectivity indicate that the disagreement between EPIC and EOS estimates depends on the sampling area, observation time and vary between     \u2212 10 %     and 23%.<\/jats:p>","DOI":"10.3390\/rs10101594","type":"journal-article","created":{"date-parts":[[2018,10,5]],"date-time":"2018-10-05T12:16:44Z","timestamp":1538741804000},"page":"1594","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Implications of Whole-Disc DSCOVR EPIC Spectral Observations for Estimating Earth\u2019s Spectral Reflectivity Based on Low-Earth-Orbiting and Geostationary Observations"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3321-1499","authenticated-orcid":false,"given":"Wanjuan","family":"Song","sequence":"first","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"},{"name":"State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences, Beijing, 100875, China"},{"name":"Beijing Engineering Research Center for Global Land Remote Sensing Products, Institute of Remote Sensing Science and Engineering, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China"}]},{"given":"Yuri","family":"Knyazikhin","sequence":"additional","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"}]},{"given":"Guoyong","family":"Wen","sequence":"additional","affiliation":[{"name":"NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA"}]},{"given":"Alexander","family":"Marshak","sequence":"additional","affiliation":[{"name":"NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2745-1966","authenticated-orcid":false,"given":"Matti","family":"M\u00f5ttus","sequence":"additional","affiliation":[{"name":"VTT Technical Research Centre of Finland, 02044 Espoo, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4262-1772","authenticated-orcid":false,"given":"Kai","family":"Yan","sequence":"additional","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"},{"name":"State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences, Beijing, 100875, China"},{"name":"Beijing Engineering Research Center for Global Land Remote Sensing Products, Institute of Remote Sensing Science and Engineering, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6127-3385","authenticated-orcid":false,"given":"Bin","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"},{"name":"College of Electrical and Information Engineering, Hunan University, Changsha 410082, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2068-8610","authenticated-orcid":false,"given":"Baodong","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"},{"name":"Macro Agriculture Research Institute, College of Resource and Environment, Huazhong Agricultural University, Wuhan 430070, China"}]},{"given":"Taejin","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8079-4079","authenticated-orcid":false,"given":"Chi","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4267-1841","authenticated-orcid":false,"given":"Yelu","family":"Zeng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences, Beijing, 100875, China"},{"name":"Department of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5030-748X","authenticated-orcid":false,"given":"Guangjian","family":"Yan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences, Beijing, 100875, China"},{"name":"Beijing Engineering Research Center for Global Land Remote Sensing Products, Institute of Remote Sensing Science and Engineering, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4812-3045","authenticated-orcid":false,"given":"Xihan","family":"Mu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences, Beijing, 100875, China"},{"name":"Beijing Engineering Research Center for Global Land Remote Sensing Products, Institute of Remote Sensing Science and Engineering, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China"}]},{"given":"Ranga B.","family":"Myneni","sequence":"additional","affiliation":[{"name":"Department of Earth and Environment, Boston University, Boston, MA 02215, USA"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4287","DOI":"10.1029\/JD092iD04p04287","article-title":"Reflectivity of earth\u2019s surface and clouds in ultraviolet from satellite observations","volume":"92","author":"Eck","year":"1987","journal-title":"J. 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