The opponent is Professor Joaquim Pinto from the Karlsruhe Institute of Technology and the custos is Docent Victoria Sinclair from the University of Helsinki.
The defence will take place in Physicum (A.I. Virtasen aukio 1, Helsinki), Auditorium E204. The public examination can also be followed online: https://video.helsinki.fi/unitube/live-stream.html?room=l41
In the dissertation, the climatological characteristics of winds and windstorms in northern Europe and Finland were studied. The results show that the wind speeds and the number of windstorms vary largely between years but no significant long-term trends were identified. The dissertation also investigated the typical structure of windstorms, how the strong wind gusts develop and what meteorological factors are most important in the subsequent development of intense windstorms in different seasons. The wind gusts were found to be at their strongest around at the same time as the minimum pressure of the windstorm occurs. The region of strongest gusts moves and extends during the windstorm development from the warm sector to behind the cold front. The analysis also shows that the strength of the windstorms is most strongly regulated by the low-level temperature gradient. Finally the dissertation examined in-depth the unique windstorm Mauri (22nd of September 1982) and its meteorological development. The investigation showed that the evolution of storm Mauri was complex and diverged from the typical development path. The results from the dissertation highlight that better understanding on windstorm development is gained when both climatological aspects and individual case studies are considered.