Abstract
Chlorophyll fluorescence (ChF) is a relevant indicator of the actual plant physiological status. In this article different methods to measure ChF from remote sensing are evaluated: the Fraunhofer Line Discrimination (FLD), the Fluorescence Radiative Method (FRM) and the improved Fraunhofer Line Discrimination (iFLD). The three methods have been applied to data acquired in the framework of the CarboEurope, FLEX and Sentinel-2 (CEFLES2) campaign in Les Landes, France in September 2007. Comparing with in situ measurements, the results indicate that the methods that provide the best results are the FLD and the iFLD with root mean square errors (RMSEs) of 0.4 and 0.5 mW m−2 sr−1 nm−1, respectively, while the FRM provides an error of 0.8 mW m−2 sr−1 nm−1.
Acknowledgements
The authors would like to thank the European Spatial Agency (CEFLES2, project 20801/07/I-LG), the Ministerio de Ciencia y Tecnología (EODIX, project AYA2008-0595-C04-01) and the European Union (CEOP-AEGIS, project FP7-ENV-2007-1 proposal no. 212921; WATCH, project 036946) for their support. We would also like to thank the groups that provided us with the data: the Laboratoire de Météorologie Dynamique (LMD) that provided us with the Airflex data and the group from University of Milano-Bicocca (UNIMIB) that provided us with the in situ measurements.