FLUXNET is a global network of micrometeorological tower sites that use eddy covariance methods to measure the exchanges of carbon dioxide, water vapor, and energy between the biosphere and atmosphere. FLUXNET is a global 'network of regional networks' that serves to provide an infrastructure to compile, archive and distribute data for the scientific community. It works to ensure that different flux networks are calibrated to facilitate comparison between sites, and it provides a forum for the distribution of knowledge and data between scientists.