This is a proposal for a reintegration activity at the Department of Meteorology and Geophysics at the University of Vienna. Proposed is an atmospheric study of small-scale processes in complex terrain that cover a range of atmospheric conditions and terrain configurations. The small-scale orographic phenomena to be examined include the following: 1) Gap flow and flow channelling in the Hinlopenstretet between the Spitzbergen and Nordaustlandet islands in the Svalbard Archipelago, 2) Atmospheric rotors in the lee of the Sierra Nevada in California and the Snowy Range in Wyoming, 3) Mountain waves and rotors in the airflow past Villarrica volcano in the Andes. These phenomena and the dynamical processes governing their generation and evolution will be examined using high-resolution airborne observations, including in situ and remote sensing data, that has been collected during several recent observational field campaigns (e.g., THORPEX-IPY, T-REX). The observational data analysis will be done in conjunction with high-resolution real-data and idealized numerical simulations using a mesoscale atmospheric numerical model (WRF) for dynamical process studies. The objective of this research is to advance our understanding of small-scale severe phenomena in complex terrain. The results of this research are expected to lead to improved accuracy of numerical weather prediction in mountainous regions. The reintegration strategy rests on building a center of excellence in mesoscale dynamics and modeling research within the Theoretical Meteorology group at the Department of Meteorology and Geophysics at the University of Vienna.