Extreme rainfall events in southern Sweden: where does the moisture come from?
Article first published online: 6 APR 2010
©2010 The Authors Tellus A © 2010 International Meteorological Institute in Stockholm
Volume 62, Issue 5, pages 605–616, October 2010
How to Cite
GUSTAFSSON, M., RAYNER, D. and CHEN, D. (2010), Extreme rainfall events in southern Sweden: where does the moisture come from?. Tellus A, 62: 605–616. doi: 10.1111/j.1600-0870.2010.00456.x
- Issue published online: 6 APR 2010
- Article first published online: 6 APR 2010
- (Manuscript received 23 September 2009; in final form 11 March 2010)
The atmospheric transport of moisture leading to extreme summer precipitation events in southern Sweden was investigated using a Lagrangian trajectory model. Surprisingly, we found that the trajectories crossed continental Europe and the Baltic Sea before arriving over Sweden; they did not arrive directly from the North Sea. Such transport pathways were not seen for a control sample of non-extreme rainfall events. We then used a new source region identification technique to investigate the hypothesis that Europe and the Baltic are important sources of the moisture that is rained out in the extreme events. Although the results varied between events, we found that this is indeed the case. Our results establish the atmospheric transport patterns that are apparently a pre-requisite for extreme rainfall events to occur in southern Sweden, and further suggest regional moisture availability may also play a key role.