The alpine atmosphere
Weather forecasters and researchers both increasingly depend on certain kinds of atmospheric models. However, the realism of such models has not been fully verified, particularly in alpine areas where fewer data points exist. The EU-funded project ROTOR (Small-scale processes in complex terrain) aimed to provide the verification. The study planned to separately examine three aspects of orographic phenomena (the atmospheric effects of mountainous terrain), at European and North and South American locations. Respective processes were studied using various high-resolution airborne measurements, plus in situ and satellite data. The project ran for four years to September 2014. Data supplied by the project supported six sub-studies. The first considered dynamics of a mobile atmospheric rotor downwind of a Wyoming mountain range, which combined simulations with measurements from a dual-Doppler cloud radar. The next involved interaction of atmospheric and oceanic wakes at Madeira, integrating simulations with readings of wind, temperature and humidity. ROTOR also modelled the propagation of an atmospheric wave over the Gulf of Mexico. Study four involved analysing Austrian ground-based wind measurements using profiling LIDAR, focusing on the wakes created by wind turbines. A modelling study further considered the effects of large orographic obstacles on convective storms. Finally, data regarding dynamically forced westerly winds in northern California fed into complex simulations. Each of the above topics was the subject of at least one master's thesis, with the students being supported by grants. Team members made numerous presentations at five separate conferences. The ROTOR project supplied atmospheric data from mountainous regions. The work helped refine and verify current models, particularly in areas having data sparsity.
