Dynamic downscaling of global climate projections for Eastern Europe with a horizontal resolution of 7 km

Abstract

Climate change is one of the key factors influencing the quantity and quality of water resources in hydrologically sensitive regions. In order to downscale global climate simulations from horizontal resolutions of about 125-200 km to about 7 km, a double nesting strategy was chosen. The modelling approach was implemented with the Regional Climate Model CCLM (COSMOClimate Local Model) with a first nesting covering a central part of Europe and with a second nesting covering parts of Poland, Belarus, and the Ukraine. A control run-driven by global reanalysis data-was evaluated by comparing the model results with corresponding reference data. Longterm yearly and monthly mean differences of temperature and precipitation were statistically assessed. As reference data for the first nesting, the gridded CRU data set with a horizontal resolution of about 55 km was used. Station data of the NOAA and ECA databases were interpolated to provide an appropriate reference data set for the second nesting. Both nestings overestimated long-term yearly precipitation means. Seasonal evaluation of the first nesting showed positive precipitation biases for spring and winter months and negative biases in summer. Furthermore, differences in the spatial precipitation patterns occured, especially in the high mountain area of the Carpathians. The second nesting overestimated precipitation in spring and summer with smaller biases than in the first nesting. Long-term area means of temperature were properly reproduced. The first nesting showed an overestimation for all months with maximal deviations in summer and spring. In contrast, the second nesting was slightly too warm for summer and autumn and too cold for winter and spring.

High-Resolution Dynamical Downscaling of ERA-Interim Using the WRF Regional Climate Model for the Area of Poland. Part 1: Model Configuration and Statistical Evaluation for the 1981–2010 Period

“…by MAROSZ et al (2013) and MAROSZ and JAKUSIK (2014). Examples of dynamical downscaling at high spatial resolution include simulations for short periods or limited to small areas of selected catchments (PAVLIK et al 2011;CZERNECKI 2013). The results of the European Coordinated Regional Climate Downscaling Experiment (EURO-CORDEX) project show the importance of dynamical downscaling for this area and also address the uncertainties related with this approach (GIORGI and GUTOWSKI 2015).…”

Comparison between high-resolution climate simulations using single- and double-nesting approaches within the Big-Brother experimental protocol

“…Hohenegger et al 2008;Chan et al 2012;Lauwaet et al 2013;Ban et al 2015;Prein et al 2015) and climate-change projections (e.g. Trapp et al 2007;Pavlik et al 2012;Kendon et al 2014) using multiple grid nesting. Such simulations indicate great perspectives for added value of high-resolution climate simulations.…”

The IWAS-ToolBox: Software coupling for an integrated water resources management

“…The river Poltva, located at Western Ukraine is a tributary to the Bug River and heavily affected by wastewater discharges and diffusive agricultural emissions, both causing severe water quality problems Pavlik et al 2011).…”