Measurements are essential to improve our understanding of atmospheric processes and interactions in the climate system. This directly influences our ability to simulate and predict past, present and future climate. In particular, there is a strong need for observations suitable to validate parameterizations used in numerical climate (and weather prediction) models and to provide ground-truth for the derivation of atmospheric parameters from satellite data. Land surface heterogeneity poses special challenges to experimental techniques to match scales between measurements, models and satellite images. A particular important role in the climate system is played by fluxes of momentum, energy and mass, these represent the interaction processes between the atmosphere and the earth’s surface.

This session is intended to give a forum to discuss recent developments and achievements in local to regional measurement concepts and technology (scales of the order of 1 to 10 km) over land with special emphasis on the measurement of fluxes of momentum, energy, water, and trace compounds. Focus will be put on techniques suitable for continuous, long-term measurements of these fluxes including radiation, turbulent energy exchange, soil heat and water fluxes, evaporation, precipitation, as well as fluxes of trace gases and aerosols. Techniques may cover in-situ and remote sensing measurements. Contributions are also invited that make use of flux data for model assessment and satellite data validation.