Long-term atmospheric measurements are essential to improve our understanding of atmospheric processes and our ability to simulate climate. In particular, there is a strong need for observations suitable to validate numerical climate and weather prediction models, to detect climate change and to validate atmospheric parameters derived from satellite data. Land surface heterogeneity poses special challenges to experimental techniques to match scales between measurements and models.

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 continuous data sets over several years up to the decadal time scale. Focus will be put on techniques suitable for continuous, long-term measurements of variables characterising the energy and water cycle components, like temperature and humidity profiles (mean values and spatial / temporal statistics), heat and water storage in the soil, radiation and turbulent energy fluxes.

Contributions are invited to report about current progress and results from methods of observation using (networks of) in-situ sensors, ground-based remote sensing techniques (such as scintillometry, lidar, sodar, radar and RASS), and operational meteorological satellites. Studies on aspects of sensors / systems performance, (automatic) quality control and quality assurance are welcomed also.