CHANGES IN HEAVY AND MEAN PRECIPITATION FROM REGIONAL CLIMATE MODEL SIMULATIONS IN EUROPE Sample Clauses

CHANGES IN HEAVY AND MEAN PRECIPITATION FROM REGIONAL CLIMATE MODEL SIMULATIONS IN EUROPE. Winter Figure 2 shows the trend of the 99th percentile of the daily precipitation sums for winter, estimated with the extreme value statistical method described above. The results are displayed separately for each model simulation of the ensemble for the time period from 1961 to 2099. In general we can see a positive trend in heavy precipitation in northern Europe which is indicated in the graphic by green and blue colours. The changes range from 1 to 10 mm with strongest values over Scandinavia. Here, an increase of 10 mm is equivalent to a 40 % higher value of the 99th percentile at the end of the time period compared to the beginning of the time period. In contrast to the positive trends in the major part of Norway, heavy precipitation along the western coast is projected to decrease or stay constant, depending on the simulation. In the graphics this is illustrated by light green or yellow colours. In comparison to northern Europe, the positive trends appear to be weaker in southern Europe. Most of the RCMs suggest that heavy precipitation decreases in the southern parts of the Iberian Peninsula and around the southern Mediterranean Sea, indicated by orange and red colours. In the strongest cases, the 99th percentiles decrease by up to 10 mm, which is equivalent to about 35-40 %. Besides the differences between northern and southern Europe, positive trends in winter are generally projected to be stronger over the continents than over the oceans. Figure 3 shows the robustness of the results in terms of inter-simulation agreement. Blue areas indicate that the majority of RCM simulations consistently project a positive trend in heavy precipitation, red areas a negative trend. The large-scale pattern of heavy precipitation changes appears to be very consistent across the simulations. The simulations agree in particular well on the positive changes in heavy precipitation over the northern and central European land masses. Inconsistencies are mainly found in regions where regional features play a large role. This is in particular the case in the mountainous regions or at the foothills of the mountains. Comparing the trends of the 99th percentile to trends in the mean precipitation (Figure 4), a similar pattern of changes is found. However, the trends in extreme precipitation are much larger in magnitude. Changes in mean precipitation range between -2 mm and 2 mm, in the graphic indicated by yellow and green colours, respectively. However, if seen in relative ...