Wettermustern

Wettermustern is a term used in meteorology to describe recurring weather configurations that shape the climate of a region over extended periods. In German-language literature the expression conveys patterns of temperature, precipitation, wind, and cloudiness that tend to reappear seasonally or persist for weeks to months.

These patterns result from the interaction of large-scale atmospheric circulation, including jet streams and pressure systems, with regional factors such as sea surface temperatures, land-sea contrasts, and topography. They can be quasi-stationary, as in blocking patterns that divert prevailing winds, or more dynamic, evolving with seasonal transitions.

Common examples include the Atlantic storm track and associated rainfall in Western Europe, persistent dry spells caused by blocking highs in parts of mid-latitude continents, monsoon-related rainfall regimes in South and Southeast Asia, and the modulation of weather by ENSO in various regions. The specific wettermustern of a region are influenced by long-term climate variability and short-term atmospheric variability, making them more or less pronounced from year to year.

Study and forecasting of wettermustern rely on long-term observations, reanalysis data, and climate models. Pattern-detection methods such as empirical orthogonal functions, cluster analysis, and teleconnection indices help scientists describe their typical forms and potential changes.

Understanding wettermustern supports weather planning, agriculture, water resources management, and disaster risk reduction. Ongoing climate change is expected to modify the frequency, intensity, and geographic location of certain patterns, with implications for regional climate projections. See also weather pattern, atmospheric blocking, NAO, ENSO, PNA.