Atmosphere data assimilation system for the Siberian region with the WRF-ARW model and three-dimensional variational analysis WRF 3D-Var

The system of the cyclic assimilation of data on atmospheric conditions used in the West Siberian Administration for Hydrometeorology and Environmental Monitoring is described. It is based on the WRF-ARW mesoscale atmospheric model and on the WRF 3D-Var system of the three-dimensional variational analysis of data. The system is verified when the first approximation data (6-hour forecast) and WRF-ARW forecasts with the lead time up to 24 hours are compared with the observational data. The problems of assimilation of observations from the AMSU-A and AIRS satellite instruments are considered. The effect of using AMSU-A and AIRS for the analysis in the Novosibirsk region is estimated. The experiments demonstrated that the cyclic data assimilation system operates successfully. The AMSU-A observations improve the quality of analyses and forecasts in winter. In summer the impact of satellite observations on the forecast skill scores is ambiguous. Good short-term forecasts are provided by the initial conditions obtained using the system of detailing of the NCEP large-scale analysis.     

The impact of radar data assimilation on atmosphere state analysis in the Moscow region

The results of numerical experiments with the data assimilation system including the WRF-ARW mesoscale atmospheric model and WRFDA analysis package in the 3D-Var mode are considered. The focus is on the impact of Doppler weather radar data on the quality of short-range weather forecasting. The maps of weather events and cloud top constructed from the modeling by GIMET-2010 software package are analyzed using the web-GIS METEORAD. The experiments in the Moscow region demonstrated that if only radial wind is assimilated, the intensity of simulated cloud and precipitation formation is the closest to the observed one; however, the spatial mismatches of simulated and observed cloud systems are possible. If Doppler radar data on radial wind and reflectivity are assimilated, the general pattern and location of clouds and precipitation are simulated more accurately, but there is a certain overestimation of convection intensity which leads to the overestimation of the number of thunderstorms and rainfall rate.     

Observed and calculated variability of the particulate matter concentration in Moscow and in Zelenograd

The results of a comparative analysis of temporal and spatial variations in the particulate matter (PM₁₀) 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 PM₁₀ concentration (an averaged correlation coefficient is 0.8), but systematically underestimated the absolute values of the PM₁₀ 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 PM₁₀ concentration and their dependence on meteorological conditions were revealed. The reasons of the formation of episodes of a high PM₁₀ concentration are considered.     

Multiscale Global Atmosphere Model SL-AV: the Results of Medium-range Weather Forecasts

Development of the multiscale version of the global atmosphere model SL-AV required many improvements in the dynamical core, replacement or refinement of parameterization algorithms and complex tuning of the model. These modifications were initially tested with the experiments on modern climate simulation and then incorporated into the model configuration for medium-range numerical weather prediction. The impact of these model improvements on forecast quality is studied in this paper. The increase in accuracy of model climate characteristics has led to the reduction of forecast errors. The comparison of quality for numerical forecasts starting from the initial data of Hydrometcenter of Russia and ECMWF is carried out. The effect of replacing the initial data turned out to be comparable to the effect of multi-year works on model development. This shows the importance and necessity of development and improvement of the Hydrometcenter of Russia data assimilation system.     

Modified equations in the theory of induced gravity. Solution to the cosmological constant problem

This research is an extension of the author’s works, in which conformally invariant generalization of string theory was suggested to higher-dimensional objects. Special cases of the proposed theory are Einstein’s theory of gravity and string theory. This work is devoted to the formation of self-consistent equations of the theory of induced gravity in the presence of matter in the form of a perfect fluid that interacts with scalar fields. The study is done to solve these equations for the case of the cosmological model. In this model time-evolving gravitational and cosmological “constants” take place which are determined by the square of scalar fields. The values of which can be matched with the observational data. The equations that describe the theory have solutions that can both match with the solutions of the standard theory of gravity as well as it can differ from it. This is due to the fact that the fundamental “constants” of the theory, such as gravitational and cosmological, can evolve over time and also depend of the coordinates. Thus, in a rather general case the theory describes the two systems (stages): Einstein and “evolving”. This process is similar to the phenomenon of phase transition, where the different phases (Einstein gravity system, but with different constants) transit into each other.     

Development of forecasting technologies for meteorological support of the Sochi-2014 Winter Olympic Games

In February–March 2014 the Winter Olympic Games will be held in Sochi. Sharp weather contrasts and high spatiotemporal variability are typical of the region of the Sochi-2014 Games. The complex mountain terrain and the intricate mixture of marine subtropical and Alpine conditions make the weather forecasting in this region extremely challenging. Although all lead times of the forecast are important for the Games, primary needs for these sport events are associated with the nowcasting and the short-range weather forecasting. The complexity of the Sochi region stimulates the development of high-resolution mesoscale modeling as a backbone of the Olympic meteorological services. Presented are the main branches of the current research in this area carried out in Roshydromet.     

WRF ARW and CHIMERE models for numerical forecasting of surface ozone concentration

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.     

Simulation of the seasonal atmospheric circulation with the new version of the semi-Lagrangian atmospheric model

Simulation of the atmospheric circulation on the seasonal scale with the new version of the global semi-Lagrangian model is considered. The new version includes land surface processes parameterization taking into account influence of the vegetation and also freezing and melting of soil moisture. The new version also includes improved parameterization for short and long wave radiation, cloudiness and atmospheric boundary layer.