Air mass

The term air mass is used in meteorology and climatology when relatively uniform parts of the troposphere are described.

With the weather forecast, the modeling of air masses with uniform temperature or humidity is an important method to predict about the course and the time evolution of fronts.

In particular, the sliding up of warm air masses relative thereto colder air masses is a physically well be modeled process by which can also be the increase in the relative humidity and the formation of clouds and precipitation fairly accurately predict.

For some phenomena also much more spacious calculations of the movement of air masses are possible - such as when global, very stable system of trade winds or jet streams.

Air mass classification

The classification of air masses takes place on the basis of the investigator tions at the University of Bergen from 1918 to 1923, led by Vilhelm Bjerknes, whose son Jacob, Halvor Solberg, and Tor Bergeron. In his dissertation (1928 ) Bergeron showed that the temperature and humidity characteristics of air masses does not change over time, while these flow over the earth's surface. The boundary between two air masses are called front and thus become a key information for weather forecasts, since this may also change the weather with the front. The difference of this air masses was attributed to two main factors. The latitude of education after four regions:

And the surface texture in these regions:

Mathematically, it can form eight basic air masses. But since Arctic or Antarctic air masses always dry and equatorial air masses are always very moist, remain six basic classes:

Air masses of Europe

The weather in Europe is mainly influenced by the following air masses.