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The coarse resolution of global climate models implies that they have a relatively poor representation of local features such as land-sea distribution and height of mountains. Also, relevant processes of the climate system, such as low-pressure systems and associated areas of precipitation implies that such models are not always fit for purpose for representing regional or local features. This is particularly problematic for some high-impact events such as high-intensity precipitation and wind storms.
GCMs provide good information about climate characteristics on large regional scales. This includes differences between continents and oceans and between high and low latitudes in general. But, also, they can provide information about climate details in parts of a continent like southern and northern Europe etc. However, at a typical GCM-resolution of 100-200 km grid spacing, complex features of the European geography such as the Mediterranean and Baltic Sea, are not well resolved. Also, mountain chains are far too low implying that their role as barriers for precipitation are often underestimated. Moreover, high-intensity events on daily and sub-daily time scales are poorly represented by such coarse models.
techniques Techniques for downscaling global model information, either dynamically through regional limited area models, or through empirical statistical methods, have been developed for this purpose.
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