Modelling LAI at a regional scale with ISBA-A-gs: comparison with satellite-derived LAI over southwestern France
-
Published:2009-08-05
Issue:8
Volume:6
Page:1389-1404
-
ISSN:1726-4189
-
Container-title:Biogeosciences
-
language:en
-
Short-container-title:Biogeosciences
Author:
Brut A.,Rüdiger C.,Lafont S.,Roujean J.-L.,Calvet J.-C.,Jarlan L.,Gibelin A.-L.,Albergel C.,Le Moigne P.,Soussana J.-F.,Klumpp K.,Guyon D.,Wigneron J.-P.,Ceschia E.
Abstract
Abstract. A CO2-responsive land surface model (the ISBA-A-gs model of Météo-France) is used to simulate photosynthesis and Leaf Area Index (LAI) in southwestern France for a 3-year period (2001–2003). A domain of about 170 000 km2 is covered at a spatial resolution of 8 km. The capability of ISBA-A-gs to reproduce the seasonal and the interannual variability of LAI at a regional scale, is assessed with satellite-derived LAI products. One originates from the CYCLOPES programme using SPOT/VEGETATION data, and two products are based on MODIS data. The comparison reveals discrepancies between the satellite LAI estimates and between satellite and simulated LAI values, both in their intensity and in the timing of the leaf onset. The model simulates higher LAI values for the C3 crops than the satellite observations, which may be due to a saturation effect within the satellite signal or to uncertainties in model parameters. The simulated leaf onset presents a significant delay for C3 crops and mountainous grasslands. In-situ observations at a mid-altitude grassland site show that the generic temperature response of photosynthesis used in the model is not appropriate for plants adapted to the cold climatic conditions of the mountainous areas. This study demonstrates the potential of LAI remote sensing products for identifying and locating models' shortcomings at a regional scale.
Publisher
Copernicus GmbH
Subject
Earth-Surface Processes,Ecology, Evolution, Behavior and Systematics
Reference54 articles.
1. Allard, V., Soussana, J.-F., Falcimagne, R., Berbigier, P., Bonnefond, J. M., Ceschia, E., D'hour, P., Hénault, C., Laville, P., Martin, C., and Pinarès-Patino, C.: The role of grazing management for the net biome productivity and greenhouse gas budget (CO2, N2O and CH4) of semi-natural grassland, Agr. Ecosyst. Environ., 121, 47–58, https://doi.org/10.1016/j.agee.2006.12.004, 2007. 2. Alessandri, A., Gualdi, S., Polcher, J., and Navarra, A.: Effects of Land Surface-Vegetation on the Boreal Summer Surface Climate of a GCM, J. Climate, 20(2), 225–278, 2007. 3. Baret, F., Hagolle, O., Geiger, B., Bicheron, P., Miras, B., Huc, M., Berthelot, B., Niño, F., Weiss, M., Samain, O., Roujean, J.-L., and Leroy, M.: LAI, fAPAR and fCover CYCLOPES global products derived from VEGETATION. Part 1: Principles of the algorithm, Remote Sens. Environ., 110, 275–286, 2007. 4. Béziat, P., Ceschia, E., and Dedieu, G.: Carbon balance of a three crop succession over two cropland sites in South West France, Agr. Forest Meteorol., 149, 1628–1645, 2009. 5. Calvet, J.-C., Noilhan, J., Roujean, J.-L., Bessemoulin, P., Cabelguenne, M., Olioso, A., and Wigneron, J.-P.: An interactive vegetation SVAT model tested against data from six contrast ing sites, Agr. Forest Meteorol., 92, 73–95, 1998.
Cited by
43 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献
|
|