Category: Europe

Europe – annual rainfall
The distribution of precipitation in Europe is decisively influenced by the topography. In addition to the altitude, windward and leeward effects also play an important role.

Much of the precipitation in Europe falls from migrating low pressure eddies. Since the lifespan of these “wandering cyclones” is usually only a few days, the associated precipitation over Europe is gradually decreasing from west to east. This results in a gradient in the distribution of precipitation from the western edge to the interior of the continent. In addition, to the east there is an increasing annual pattern of precipitation with a summer rain maximum, also known as hygric continentality. The increased rainfall in summer results from the strong warming of the mainland masses in the interior of the continent. This leads to vertical air movements and convective clouds with corresponding precipitation.

In addition to the west-east gradient in the distribution of precipitation in Europe, there is a clear change in the elevation of the amount of precipitation. As a rule, precipitation increases with increasing altitude. The reasons for this are both congestion effects and the higher wind speeds in the mountain regions, which accelerate the supply of moist air masses. A north-south orientation of the mountain ranges additionally intensifies this effect due to the westerly winds prevailing in the altitude. This is particularly evident in the western roof of the Scandinavian Mountains. In the lee of such mountains, precipitation decreases significantly due to the effects of the wind, such as in the highlands of Spain.

In summer, a wedge of the subtropical high over the Azores diverts the low pressure areas over Europe to the north, thereby keeping them away from the Mediterranean. In winter, however, the west wind jet is shifted south and now directs Atlantic lows into the Mediterranean area. In addition, independent low-pressure eddies arise over the relatively warm Mediterranean region, such as over the Golfe du Lion or the Gulf of Genoa. For this reason, the rainfall around the Mediterranean falls mainly in the winter half-year. For more information about the continent of Europe, please check politicsezine.com.