Evaluation of WRF-Forecasts Over Siberia: Air Mass Formation, Clouds and Precipitation

摘要: The Weather Research and Forecasting (WRF) model was run as a regional without data assimilation or nudging (31 36h-simulations) for July December 2005 over limited area domain covering Siberia to examine weather formation in an air-mass source region. WRF-results were compared NCEP1/NCAR-reanalysis, International Satellite Cloud Climatology Project, Global Precipitation Centre Canadian Meteorological assess performance identify shortcomings. WRF is capable of predicting formation. Simulation errors are within the error range other models. timing best/worst agreement differs among quantities depending on their sensitivity systematic (model deficiencies) and/or unsystematic (e.g. initial conditions). Overall, agree better with reanalysis than December. best under persistent high pressure worst during frontal passages transition from one regime another. In July, provides smaller diurnal amplitudes 2m-temperature up 5.4 K lower, 3.5 higher values at 0000 1200 UTC reanalysis. December, overestimates by 1.4 K. WRF-temperatures excellently 700 hPa 300 hPa. Except passages, wind-speed shows positive bias. Typically root-mean-square standard deviation (temperature) increase (decrease) height. has difficulty position strength polar jet. underestimates cloudiness snow-depth, but precipitation. predicted convective precipitation related strongly boundaries between different land-cover. WRF-predicted snow-depth correlates terrain misses observed fine features.