Climatology of precipitation in the Vosges Mountain range area

Abstract

The aim of this work is to study the climatology of atmospheric precipitation in the study area situated in north-eastern France. It is shown that the Vosges mountain range, due to its position almost perpendicular to the prevailing western airflow, affects the spatial and temporal distribution (and thus the seasonality) of precipitation at a regional scale. This is carried out by computing the daily rainfall at 14 meteorological stations over the period 1950-2011. Different levels of rainfall resolution were examined - at first the annual rainfall which varies greatly between the windward side and the highest part of the Vosges mountain range and the Upper Rhine Plain (the difference is as large as 1700 mm per average year), then the monthly rainfall and distribution of precipitation within the year and finally the daily rainfall variability. Three categories of stations were determined according to their annual precipitation distribution: (i) mountain stations with a winter precipitation maximum, (ii) leeward slope stations with two precipitation maxima, i.e. in winter and summer and (iii) leeward stations located in the Upper Rhine Plain eastward of the Vosges with a summer precipitation maximum. Quantitative methods of ombric continentality demonstrate that the Vosges represent a limit between oceanic and a more continental climate. However, the empirical formulas are not satisfying and further research is required.