Climate Exchange

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and studies use the Intergovernmental Panel on Climate Change

(IPCC) emission scenarios A1B, A2, B1 and B2. However, other

emission scenarios are also applied in a few projects and studies.

Different Global and Regional Circulation Models are used as

meteorological drivers, so spatial resolution of the simulation

results varies. The future development is mainly based on single

model runs, only some projects use ensemble model runs. Finally,

different dynamical and statistical downscaling methods are

applied to model the future development of air temperature and

precipitation with a spatial resolution between 1 km and 10 km.

As reference periods mainly the periods 1961-1990 and 1971-2000

are used and most of the simulations are projected for the future

periods 2021-2050 and 2071-2100.

Air temperature

In total, 59 projects and studies with statements regarding IPCC

scenarios or trends were analysed, and all of them assume a tempera-

ture increase during this century, both annually and in every season,

with a rising gradient from north-west to south-east in the DRB.

While there are considerable differences in the investigated areas

due to climate influencing factors like altitude, mountainous massifs

and seas, the main future trends are similar for all areas. Also the

mean temperatures of all seasons are likely to increase, only for

winter all models show a relatively high uncertainty.

Precipitation

The DRB is located in the transition zone between expected

increasing (Northern Europe) and decreasing (Southern Europe)

future precipitation. According to the analysed projects, mean

annual values in many countries of the DRB will most likely remain

almost constant, but seasonally and regionally large changes are

projected for the twenty-first century. A decrease in summer

Source: LMU

Change of mean annual and mean summer temperature in the Danube River Basin for 2021-2050

and 2071-2100 according to A1B scenario of different model results

Source: LMU

Change of mean annual precipitation in the

Danube River Basin for the periods 2021-2050 and

2071-2100 according to A1B scenario of different

model results

2021-2050

2071-2100

2021-2050

2071-2100

Mean annual

temperature changes

Mean summer

temperature changes