Towards a standardized processing of Net Ecosystem Exchange measured with eddy covariance technique: algorithms and uncertainty estimation
1Department of Forest Science and Environment, University of Tuscia, 01100 Viterbo, Italy
2Max-Planck Institut fur Biogeochemie, P.O. Box 100164, 07701 Jena, Germany
3Faculté des Sciences Agronomiques, Avenue de la Faculté d'Agronomie 8, 5030 Gembloux, Belgium
4Dept. of Meteorology, Institute of Hydrology and-Meteorology, Technische Universitat Dresden, 01062 Dresden, Germany
5Ecologie et Ecophysiologie Forestières, Centre de Nancy, 54280 Champenoux, France
6Dream CEFE-CNRS, 1919 route de Mende, 34293 Montpellier, France
7Department of Physical Sciences, University of Helsinki, P.O. Box 64, FIN-00014, Finland
8Dept. of Environmental Sciences and Energy Research, Weizmann Institute of Science, P.O. Box 26, 76100 Rehovot, Israel
Abstract. Eddy covariance technique to measure CO2, water and energy fluxes between biosphere and atmosphere is widely spread and used in various regional networks. Currently more than 250 eddy covariance sites are active around the world measuring carbon exchange at high temporal resolution for different biomes and climatic conditions. In this paper a new standardized set of corrections is introduced and the uncertainties associated with these corrections are assessed for eight different forest sites in Europe with a total of 12 yearly datasets. The uncertainties introduced on the two components GPP (Gross Primary Production) and TER (Terrestrial Ecosystem Respiration) are also discussed and a quantitative analysis presented. Through a factorial analysis we find that generally, uncertainties by different corrections are additive without interactions and that the heuristic u*-correction introduces the largest uncertainty. The results show that a standardized data processing is needed for an effective comparison across biomes and for underpinning inter-annual variability. The methodology presented in this paper has also been integrated in the European database of the eddy covariance measurements.
Papale, D., Reichstein, M., Aubinet, M., Canfora, E., Bernhofer, C., Kutsch, W., Longdoz, B., Rambal, S., Valentini, R., Vesala, T., and Yakir, D.: Towards a standardized processing of Net Ecosystem Exchange measured with eddy covariance technique: algorithms and uncertainty estimation, Biogeosciences, 3, 571-583, doi:10.5194/bg-3-571-2006, 2006.