Due to climate change, the cycle of precipitation and evaporation is going to be intensified. Within the next hundred years, the global mean precipitation might increase by several percent. For scenario A1B for example, our simulations show an increase of approximately 7 percent by 2100. However, the spatial and temporal distribution of the rainfall will also change: increases are shown with red colors, decreases are shown in blue.

IPCC A1B Precipitation Change (Summer/Winter) with ECHAM5/MPI-OM

 

In order to evaluate the simulated percentaged precipitation changes for January and July shown above, it might be helpul to know the "normal" mean rainfall in the different regions for the respective seasons. The following images and the animation concurrently show the simulated precipitation for 1961-1990 and the changes by the end of this century simulated for IPCC scenario A1B.

 

Precipitation and Precipitation Change for the Summer Season The simulated mean precipitation over land in the summer season (June, July, August) for the period 1961-1990 is shown by the height of the bars. The percentaged changes in the mean precipitation for scenario A1B, simulated for 2070-2100, is given by the colors. (JPEG, 130 kB).
Precipitation and Precipitation Change for the Winter Season The simulated mean precipitation over land in the winter season (December, January, February) for the period 1961-1990 is shown by the height of the bars. The percentaged changes in the mean precipitation for scenario A1B, simulated for 2070-2100, is shown by the colors. (JPEG, 130 kB).
Niederschlagsänderung DJF Thumb Based on the 20C simulations, this animation shows the annual cycle of the mean monthly precipitation for 1961-1990, being visualiszed by the height of the bars. The percentaged changes in the mean monthly precipitation for scenario A1B in 2070-2100 are shown by the colors. (MPEG, 2.7 MB).

 

It can be expected, that a strong decrease in precipitation (yellow to red) will have a strong impact on the vegetation and agriculture, especially in areas with naturally little precipitation (short bars).