{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T23:49:45Z","timestamp":1773359385373,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2015,11,18]],"date-time":"2015-11-18T00:00:00Z","timestamp":1447804800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Postdoctoral Science Foundation","award":["2015M570886"],"award-info":[{"award-number":["2015M570886"]}]},{"name":"Open fund of state key laboratory of remote sensing science","award":["OFSLRSS201518"],"award-info":[{"award-number":["OFSLRSS201518"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Albedo characterizes the radiometric interface of land surfaces, especially vegetation, and the atmosphere. Albedo is a critical input to many models, such as crop growth models, hydrological models and climate models. For the extensive attention to crop monitoring, a physical albedo model for crops is developed based on the law of energy conservation and spectral invariants, which is derived from a prior forest albedo model. The model inputs have been efficiently and physically parameterized, including the dependency of albedo on the solar zenith\/azimuth angle, the fraction of diffuse skylight in the incident radiance, the canopy structure, the leaf reflectance\/transmittance and the soil reflectance characteristics. Both the anisotropy of soil reflectance and the clumping effect of crop leaves at the canopy scale are considered, which contribute to the improvement of the model accuracy. The comparison between the model results and Monte Carlo simulation results indicates that the canopy albedo has high accuracy with an  RMSE &lt; 0.005. The validation using ground measurements has also demonstrated the reliability of the model and that it can reflect the interaction mechanism between radiation and the canopy-soil system.<\/jats:p>","DOI":"10.3390\/rs71115536","type":"journal-article","created":{"date-parts":[[2015,11,18]],"date-time":"2015-11-18T10:35:12Z","timestamp":1447842912000},"page":"15536-15560","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Estimating Crop Albedo in the Application of a Physical  Model Based on the Law of Energy Conservation and  Spectral Invariants"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6512-2066","authenticated-orcid":false,"given":"Jingjing","family":"Peng","sequence":"first","affiliation":[{"name":"Institute of RS and GIS, Peking University, Beijing 100871, China"},{"name":"State Key Laboratory of Remote Sensing Science, jointly sponsored by Institute of Remote Sensing and Digital Earth of CAS and Beijing Normal University, Beijing 100101, China"}]},{"given":"Wenjie","family":"Fan","sequence":"additional","affiliation":[{"name":"Institute of RS and GIS, Peking University, Beijing 100871, China"},{"name":"The Beijing Key Laboratory of Spatial Information Integration and 3S Application, Beijing 100871, China"}]},{"given":"Xiru","family":"Xu","sequence":"additional","affiliation":[{"name":"Institute of RS and GIS, Peking University, Beijing 100871, China"},{"name":"The Beijing Key Laboratory of Spatial Information Integration and 3S Application, Beijing 100871, China"}]},{"given":"Lizhao","family":"Wang","sequence":"additional","affiliation":[{"name":"Beijing Research Institute of Automation for Machinery Industry, Beijing 100120, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3713-9511","authenticated-orcid":false,"given":"Qinhuo","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Remote Sensing Science, jointly sponsored by Institute of Remote Sensing and Digital Earth of CAS and Beijing Normal University, Beijing 100101, China"},{"name":"Joint Center for Global Change Studies, Beijing 100875, China"}]},{"given":"Jvcai","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of RS and GIS, Peking University, Beijing 100871, China"},{"name":"The Beijing Key Laboratory of Spatial Information Integration and 3S Application, Beijing 100871, China"}]},{"given":"Peng","family":"Zhao","sequence":"additional","affiliation":[{"name":"Institute of RS and GIS, Peking University, Beijing 100871, China"},{"name":"The Beijing Key Laboratory of Spatial Information Integration and 3S Application, Beijing 100871, China"}]}],"member":"1968","published-online":{"date-parts":[[2015,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Jacob, F., and Olioso, A. 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