In fall and winter, when westerly and south-westerly winds dominate, there is a strong orographic control of precipitation distribution and amounts (Isemer et al. Several observational studies have assessed extreme precipitation events in the Fenno-Scandinavian region and the associated role of certain atmospheric circulation patterns, on an annual basis (Irannezhad et al. Projected changes in precipitation amounts, snowpack and snow cover will considerably impact surface hydrology through, for example, changed surface runoff as well as timing and amplitude of the spring flood (von Storch et al. Further, the hydrological cycle intensifies (Bengtsson 2010) leading to more precipitation as well as more intense extreme events (e.g. As a result of global warming, the probabilities for winter cold episodes in this region are projected to decrease significantly (Benestad 2011) and summer warm extremes to be more pronounced (e.g. Projected future warming in northern Europe is among the largest in the world, driven to a large extent by the strong positive feedback involving reduction of snow and ice as the climate warms (Collins et al. These results, indicating clear benefits of convection-permitting models, are encouraging motivating further exploration of added value in this region, and provide a valuable basis for impact studies. Examining instead the relative occurrence of snowfall versus rain, which is sensitive to variance in topographic heights it is shown that HCLIM3 provides added value compared to HCLIM12 also for winter precipitation. Considerable undercatchment in observations may partly explain the wet bias. Simulated winter precipitation is biased high, primarily over complex terrain. This is the case even though the model exhibits a cold bias in near-surface temperature, particularly for daily maximum temperatures in summer. HCLIM3 strongly improves the representation of precipitation compared to HCLIM12, most evident through reduced “drizzle” and increased occurrence of higher intensity events as well as improved timing and amplitude of the diurnal cycle. Model results are evaluated against reanalysis and various observational data sets, some at high resolutions. HCLIM12 uses lateral boundaries from ERA-Interim reanalysis. We use the HARMONIE-Climate (HCLIM) model on two nested grids one covering Europe at 12 km resolution (HCLIM12) using parameterized convection, and one covering Fenno-Scandinavia with 3 km resolution (HCLIM3) with explicit deep convection. Here, we present the first long-term (1998–2018) simulation with a regional convection-permitting climate model for Fenno-Scandinavia. Convection-permitting climate models have shown superior performance in simulating important aspects of the precipitation climate including extremes and also to give partly different climate change signals compared to coarser-scale models.
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