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EPIC Spectral Observations of Variability in Earth’s Global Reflectance

NASA’s Earth Polychromatic Imaging Camera (EPIC) onboard NOAA’s Deep Space Climate Observatory (DSCOVR) satellite observes the entire sunlit Earth every 65 to 110 min from the Sun–Earth Lagrangian L1 point. This paper presents initial EPIC shortwave spectral observations of the sunlit Earth reflecta...

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Detalles Bibliográficos
Autores principales: Yang, Weidong, Marshak, Alexander, Várnai, Tamás, Knyazikhin, Yuri
Formato: Online Artículo Texto
Lenguaje:English
Publicado: 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6800679/
https://www.ncbi.nlm.nih.gov/pubmed/31632826
http://dx.doi.org/10.3390/rs10020254
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author Yang, Weidong
Marshak, Alexander
Várnai, Tamás
Knyazikhin, Yuri
author_facet Yang, Weidong
Marshak, Alexander
Várnai, Tamás
Knyazikhin, Yuri
author_sort Yang, Weidong
collection PubMed
description NASA’s Earth Polychromatic Imaging Camera (EPIC) onboard NOAA’s Deep Space Climate Observatory (DSCOVR) satellite observes the entire sunlit Earth every 65 to 110 min from the Sun–Earth Lagrangian L1 point. This paper presents initial EPIC shortwave spectral observations of the sunlit Earth reflectance and analyses of its diurnal and seasonal variations. The results show that the reflectance depends mostly on (1) the ratio between land and ocean areas exposed to the Sun and (2) cloud spatial and temporal distributions over the sunlit side of Earth. In particular, the paper shows that (a) diurnal variations of the Earth’s reflectance are determined mostly by periodic changes in the land–ocean fraction of its the sunlit side; (b) the daily reflectance displays clear seasonal variations that are significant even without including the contributions from snow and ice in the polar regions (which can enhance daily mean reflectances by up to 2 to 6% in winter and up to 1 to 4% in summer); (c) the seasonal variations of the sunlit Earth reflectance are mostly determined by the latitudinal distribution of oceanic clouds.
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spelling pubmed-68006792019-10-19 EPIC Spectral Observations of Variability in Earth’s Global Reflectance Yang, Weidong Marshak, Alexander Várnai, Tamás Knyazikhin, Yuri Remote Sens (Basel) Article NASA’s Earth Polychromatic Imaging Camera (EPIC) onboard NOAA’s Deep Space Climate Observatory (DSCOVR) satellite observes the entire sunlit Earth every 65 to 110 min from the Sun–Earth Lagrangian L1 point. This paper presents initial EPIC shortwave spectral observations of the sunlit Earth reflectance and analyses of its diurnal and seasonal variations. The results show that the reflectance depends mostly on (1) the ratio between land and ocean areas exposed to the Sun and (2) cloud spatial and temporal distributions over the sunlit side of Earth. In particular, the paper shows that (a) diurnal variations of the Earth’s reflectance are determined mostly by periodic changes in the land–ocean fraction of its the sunlit side; (b) the daily reflectance displays clear seasonal variations that are significant even without including the contributions from snow and ice in the polar regions (which can enhance daily mean reflectances by up to 2 to 6% in winter and up to 1 to 4% in summer); (c) the seasonal variations of the sunlit Earth reflectance are mostly determined by the latitudinal distribution of oceanic clouds. 2018 /pmc/articles/PMC6800679/ /pubmed/31632826 http://dx.doi.org/10.3390/rs10020254 Text en licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons by Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Yang, Weidong
Marshak, Alexander
Várnai, Tamás
Knyazikhin, Yuri
EPIC Spectral Observations of Variability in Earth’s Global Reflectance
title EPIC Spectral Observations of Variability in Earth’s Global Reflectance
title_full EPIC Spectral Observations of Variability in Earth’s Global Reflectance
title_fullStr EPIC Spectral Observations of Variability in Earth’s Global Reflectance
title_full_unstemmed EPIC Spectral Observations of Variability in Earth’s Global Reflectance
title_short EPIC Spectral Observations of Variability in Earth’s Global Reflectance
title_sort epic spectral observations of variability in earth’s global reflectance
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6800679/
https://www.ncbi.nlm.nih.gov/pubmed/31632826
http://dx.doi.org/10.3390/rs10020254
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