Regional atmospheric and surface layer data as a result of use of WRF and WRF- FDDA based on ERA-40 reanalysis and observation data

At present northern regions demonstrate climate change acceleration. For investigation of regional climate changes and analysis of the reasons of changes inhomogeneities it is necessary to have data with higher spatial resolution, which takes into account region specificity. Modern mesoscale meteorological models and assimilation systems can be used to solve this task. The regional weather forecast model (WRF) and data assimilation system WRF-VAR (WRFDA) are used to obtain fields of atmospheric and surface layer data for chosen calculation area of Western Siberia (2500x2000 km.). At the first stage the time slot considered is 1990-2000. Vertical boundary conditions, as well as initial conditions are formed using ERA-40 reanalysis data, while NCEP data and USGS LULC map with spatial resolution of 9.25 km are used to determine lower boundary conditions. Measurements of weather stations, located within calculation area, are used for analysis nudging. As a result of the model run, we have meteorological fields, which are reanalysis fields’ projections with high spatial resolution (10-20 km) corrected by weather stations’ measurements. On the next step it is planned to calculate data for time slot 1960-1990. Primary analysis of the data obtained allows us to depict changes of climatic characteristics for local areas not as smoothed disturbances (as for reanalysis fields), but as local inhomogeneities that have specific geographical reference to regional ecosystem. Key parameters characterizing the main local climate dynamics trends will be chosen for further analysis and processing. The work has been partially supported by SB RAS integration projects Nos. 50 and 66.