A database containing sub-seasonal to seasonal forecasts from 11 operational 30 centres is available to the research community and will help advance our understanding of 31 the sub-seasonal to seasonal time range.Abstract 51 52Demands are growing rapidly in the operational prediction and applications communities for 53 forecasts that fill the gap between medium-range weather and long-range or seasonal 54

No abstract

The results of a comparative analysis of temporal and spatial variations in the particulate matter (PM 10 ) concentration are under consideration; the information is obtained based on the measurement data from the Mosekomonitoring network of stations and results of calculations with the CHIMERE chemistry transport model adapted for the Russian central region. The intercomparison of measurement data obtained in summer 2007 and respective calculations showed that the model provided a satisfactory reproduction of the observed temporal variability of the daily mean PM 10 concentration (an averaged correlation coefficient is 0.8), but systematically underestimated the absolute values of the PM 10 concentration. It is shown that model data quality can be significantly improved due to a simple a priori correction of the model errors. Irregularities in the spatial distribution of the PM 10 concentration and their dependence on meteorological conditions were revealed. The reasons of the formation of episodes of a high PM 10 concentration are considered.

Results of joint calculations with meteorological WRF ARW model and chemistry transport CHIMERE model are considered as a basis of the modern system of the air quality assessment and forecasting. The system was designed in the Russian Hydrometeorological Center and Institute of Applied Physics of the Russian Academy of Sciences. Detailed prognostic information about the atmosphere state provided by the WRF ARW was used in the CHIMERE model for describing the air mass transport processes, chemical transformation, and pollution deposition. Results of retrieval and forecast of surface ozone concentration as one of main air quality indicators are under consideration. Calculations of ozone concentrations for different configurations of a prognostic system differ in resolution of model grid and in the way the boundary conditions are prescribed.

No abstract