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High-resolution precipitation data
Monitoring precipitation on small spatial scales, including the variation of extremes, is a prerequisite for the development of adaptation options in a future with changing precipitation characteristics.
Different types of downscaling methods are used in the EURO4M project. The coarse fields of a global reanalysis dataset at ~ 125 km (ERA40) are dynamically downscaled to a resolution of 25 km in the EURO4M area. The increased resolution provides more detail and realism due to the use of both an advanced analysis of observations (3D-VAR) and a 25 km grid point model. Fields from this reanalysis are then used in a second two-dimentional mesoscale downscaling step involving additional observations. This results in a dataset with a spatial resolution of the order of 5 km. This is possible by an optimal combination of observations and model fields where errors based on, for example, differences in topography and land/water mask are taken into consideration.
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Accumulated precipitation over the Baltic region during the month of January 2009 based on a mesoscale reanalysis at a resolution of 10 km. (Source: SMHI)
Precipitation over the Alps feeds four major European rivers and plays a crucial role in supplying water to the continent, in shaping Alpine ecosysems and in providing hydropower for civilization. Heavy precipitation can also cause flash floods, land slides and avalanches. This map shows observed precipitation in August 2005, when more than 150 mm of rain fell within 3 days over Austria, Germany and Switzerland. Six casualties and more than 2 billion Euros in damage occured within Switzerland alone. (Source: MeteoSwiss)
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