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Due to differences identified between modeled and observed precipitation in the catchments of Evinos and Mornos, daily precipitation and temperature data provided by SWICCA, with spatial analysis of 0.5 degrees, were downscaled based on local data. Mean values, mean & variance and Full PDF correction was applied. We note that Full PDF correction led to historical time series with statistical characteristics better matching the observed time series, than BC corrected data. However, Full PDF correction led to time series for the future period which depict a significantly different climate change than the change predicted by the original, 0.5 degrees SWICCA data. This was not observed for the BC corrected time series.
In order to cope with this issue, there was an effort to change the Full PDF correction rules applied for close-to-zero daily precipitation, since we noticed that Full PDF correction led to time series with a lot of zero daily precipitation values. This effort led to slightly better results but still the problem remained. Another correction effort was based on removing the trend from the historical 0.5 degrees time series, applying the Full PDF correction then and adding the trend back again. That approach kind of corrected the problem. However, we decided to use the BC corrected time series.