{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T15:34:17Z","timestamp":1783784057848,"version":"3.55.0"},"reference-count":52,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,8,11]],"date-time":"2017-08-11T00:00:00Z","timestamp":1502409600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006360","name":"Bundesministerium f\u00fcr Wirtschaft und Energie","doi-asserted-by":"publisher","award":["50EE1218"],"award-info":[{"award-number":["50EE1218"]}],"id":[{"id":"10.13039\/501100006360","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010661","name":"Horizon 2020","doi-asserted-by":"publisher","award":["641762"],"award-info":[{"award-number":["641762"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Quantifying the accuracy of remote sensing products is a timely endeavor given the rapid increase in Earth observation missions. A validation site for Sentinel-2 products was hence established in central Germany. Automatic multispectral and hyperspectral sensor systems were installed in parallel with an existing eddy covariance flux tower, providing spectral information of the vegetation present at high temporal resolution. Normalized Difference Vegetation Index (NDVI) values from ground-based hyperspectral and multispectral sensors were compared with NDVI products derived from Sentinel-2A and Moderate-resolution Imaging Spectroradiometer (MODIS). The influence of different spatial and temporal resolutions was assessed. High correlations and similar phenological patterns between in situ and satellite-based NDVI time series demonstrated the reliability of satellite-based phenological metrics. Sentinel-2-derived metrics showed better agreement with in situ measurements than MODIS-derived metrics. Dynamic filtering with the best index slope extraction algorithm was nevertheless beneficial for Sentinel-2 NDVI time series despite the availability of quality information from the atmospheric correction procedure.<\/jats:p>","DOI":"10.3390\/s17081855","type":"journal-article","created":{"date-parts":[[2017,8,11]],"date-time":"2017-08-11T10:07:40Z","timestamp":1502446060000},"page":"1855","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":83,"title":["Validating MODIS and Sentinel-2 NDVI Products at a Temperate Deciduous Forest Site Using Two Independent Ground-Based Sensors"],"prefix":"10.3390","volume":"17","author":[{"given":"Maximilian","family":"Lange","sequence":"first","affiliation":[{"name":"Department Computational Landscape Ecology, Helmholtz-Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5171-2364","authenticated-orcid":false,"given":"Benjamin","family":"Dechant","sequence":"additional","affiliation":[{"name":"Department Computational Landscape Ecology, Helmholtz-Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany"},{"name":"Department Computational Hydrosystems, Helmholtz-Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Corinna","family":"Rebmann","sequence":"additional","affiliation":[{"name":"Department Computational Hydrosystems, Helmholtz-Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6048-1163","authenticated-orcid":false,"given":"Michael","family":"Vohland","sequence":"additional","affiliation":[{"name":"Leipzig University, Institute for Geography, Geoinformatics and Remote Sensing, Johannisallee 19a, 04103 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Cuntz","sequence":"additional","affiliation":[{"name":"Department Computational Hydrosystems, Helmholtz-Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany"},{"name":"INRA, Universit\u00e9 de Lorraine, UMR1137 Ecologie et Ecophysiologie Foresti\u00e8re, 54280 Champenoux, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Doktor","sequence":"additional","affiliation":[{"name":"Department Computational Landscape Ecology, Helmholtz-Centre for Environmental Research-UFZ, Permoserstr. 15, 04318 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3383","DOI":"10.1080\/014311600750020000","article-title":"Developments in the \u2018validation\u2019 of satellite sensor products for the study of the land surface","volume":"21","author":"Justice","year":"2000","journal-title":"Int. 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