Climate studies

are on the one hand long-term analyses about measurements of different climate parameters (e.g. rainfall, temperature, phenology) and on the other hand, data from climate projections to be analyzed and further processed for practical applications.

Both types of studies are performed by our team.

Analysis of climate measurements

Long-term measurements (over a period of at least 30 – 50 years) are analyzed to investigate if systematic changes occurred. These changes can be visible on parameters like the annual sum, yearly rainfall, extreme values on the daily or hourly time scale.
In cooperation with Dr. Papadakis GmbH and aqua_plan GmbH, we showed within the project ExUS for the LANUV NRW, that between 1950 and 2008 in NRW the rainfall during winter seasons increased significantly. However, there was no clear tendency for summer rainfalls.

Karte Exus Winter 1950-2008

For the federal land Sachsen-Anhalt we performed a climate analysis together with CEC Potsdam. It could be demonstrated for the years from 1951 to 2014, that the yearly rainfall has changed, the temperature has increased and that the growing season has extended by several days.

Titelseite des Endberichts

Climate Projections

Climate projections are calculations which are performed by climate models to calculate the conditions in the future (generally until 2100). The results can show the following characteristics, which prevent a direct application in the hydrological practice (e.g. rainfall-runoff-simulation or sewer models):

  • systematic deviation (Bias): a correction needs to be determined, which transfers the conditions of a historical time period, for which model data and measurement data are available, to future periods.

  • temporal resolution: for a lot of applications temporal resolutions in the range of 1 hour or 1 day are too inaccurate (particularly urban hydrology, small catchment basins, extreme events). A temporal downscaling will be necessary.

  • spatial resolution: climate models can exhibit a spatial grid resolution of 100 to 400 km². This is too coarse for most hydrological applications and requires a spatial downscaling process.

We have developed a downscaling strategy during our participation in the BMBF-project dynaklim and have used this technique in different projects (e.g. DynAlp, DevoBeta-CC, ConQuad).

Downscaling Dynaklim