76973 20200117221625.0 doi 10.3390/rs10122061 sideral 109864 ART-2018-109864 eng Melendo-Vega, J.R. Improving the performance of 3-D radiative transfer model FLIGHT to simulate optical properties of a tree-grass ecosystem 2018 Access copy available to the general public Unrestricted The 3-D Radiative Transfer Model (RTM) FLIGHT can represent scattering in open forest or savannas featuring underlying bare soils. However, FLIGHT might not be suitable for multilayered tree-grass ecosystems (TGE), where a grass understory can dominate the reflectance factor (RF) dynamics due to strong seasonal variability and low tree fractional cover. To address this issue, we coupled FLIGHT with the 1-D RTM PROSAIL. The model is evaluated against spectral observations of proximal and remote sensing sensors: the ASD Fieldspec® 3 spectroradiometer, the Airborne Spectrographic Imager (CASI) and the MultiSpectral Instrument (MSI) onboard Sentinel- 2. We tested the capability of both PROSAIL and PROSAIL+FLIGHT to reproduce the variability of different phenological stages determined by 16-year time series analysis of Moderate Resolution Imaging Spectroradiometer-Normalized Difference Vegetation Index (MODIS-NDVI). Then, we combined concomitant observations of biophysical variables and RF to test the capability of the models to reproduce observed RF. PROSAIL achieved a Relative Root Mean Square Error (RRMSE) between 6% to 32% at proximal sensing scale. PROSAIL+FLIGHT RRMSE ranged between 7% to 31% at remote sensing scales. RRMSE increased in periods when large fractions of standing dead material mixed with emergent green grasses -especially in autumn-; suggesting that the model cannot represent the spectral features of this material. PROSAIL+FLIGHT improves RF simulation especially in summer and at mid-high view angles. info:eu-repo/grantAgreement/ES/MINECO/CGL2015-G9095-R info:eu-repo/grantAgreement/ES/MINECO/CGL2012-34383 info:eu-repo/grantAgreement/ES/MEC/FPU15-03558 info:eu-repo/semantics/openAccess by http://creativecommons.org/licenses/by/3.0/es/ 4.118 2018 REMOTE SENSING 7 / 30 = 0.233 2018 Q1 T1 1.43 2018 Earth and Planetary Sciences (miscellaneous) 2018 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Martín, M.P. Pacheco-Labrador, J. González-Cascón, R. Moreno, G. (orcid)0000-0003-4831-4060 Pérez, F. Universidad de Zaragoza Migliavacca, M. García, M. North, P. Riaño, D. 3006 010 Universidad de Zaragoza Dpto. Geograf. Ordenac.Territ. Área Análisis Geográfico Regi. 10, 12 (2018), 2061 [33 pp] Remote sens. (Basel) Remote Sensing 2072-4292 1387931 http://zaguan.unizar.es/record/76973/files/texto_completo.pdf Versión publicada 105433 http://zaguan.unizar.es/record/76973/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:76973 articulos driver 2020-01-17-21:56:34 ARTICLE