 |
| Titel |
Modelling LAI at a regional scale with ISBA-A-gs: comparison with satellite-derived LAI over southwestern France |
| VerfasserIn |
A. Brut, C. Rüdiger, S. Lafont, J.-L. Roujean, J.-C. Calvet, L. Jarlan, A.-L. Gibelin, C. Albergel, P. Moigne, J.-F. Soussana, K. Klumpp, D. Guyon, J.-P. Wigneron, E. Ceschia |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1726-4170
|
| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 6, no. 8 ; Nr. 6, no. 8 (2009-08-05), S.1389-1404 |
| Datensatznummer |
250003937
|
| Publikation (Nr.) |
 copernicus.org/bg-6-1389-2009.pdf |
|
|
|
|
|
| Zusammenfassung |
| 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. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|