Mesoscale Meteorological Model Tsunm3 for the Study and Forecast of Meteorological Parameters of the Atmospheric Surface Layer Over a Major Population Center

Abstract

The paper describes the mathematical formulation and numerical method of the TSUNM3 high-resolution mesoscale meteorological model being developed at Tomsk State University. The model is nonhydrostatic and includes three-dimensional nonstationary equations of hydrothermodynamics of the atmospheric boundary layer with parameterization of turbulence, moisture microphysics, long-wave and short-wave (solar) radiation, and advective and latent heat flows in the atmosphere and at the boundary of its interaction with the underlying surface. The numerical algorithm is constructed using structured grids with uniform spacing in horizontal directions and condensing to the Earth surface in the vertical direction. When approximating the differential formulation of the problem, the finite volume method with the second order approximation in the spatial variables is used. Explicit-implicit approximations in time (Adams–Bashforth and Crank–Nicolson) are used to achieve second-order accuracy in time. The paper presents results of numerical forecasting of the main meteorological parameters of the atmosphere (temperature, humidity, wind speed and direction) and precipitation in different seasons in the Siberian region. The models were tested with the help of observations obtained using the Volna-4M sodar, MTR-5 temperature profile meter, and Meteo-2 ultrasonic weather stations of the Atmosfera Collective Use Center. The improved TSUNM3 model is shown to adequately reflect the precipitation time and intensity. However, in some cases, the times of its beginning and end do not always coincide, the difference can reach several hours. The precipitation phase state is reflected reliably. Over 70% of precipitation cases are confirmed by numerical calculations. The model satisfactorily predicts temperature and humidity characteristics. The quality of the precipitation forecast model is comparable to the modern mesoscale models, such as the Weather Research and Forecasting (WRF) model.

Application of the numerical model TSUNM3 to study the urban heat island and the intensity of precipitation over the Siberian city of Tomsk

“…The developed mesoscale model was applied to the study of meteorological conditions over the city of Tomsk (85.0 о E 56.5 о N, center of the city) and Bogashevo airport (Aeroport, 85.21 о E, 56.38 о N) (Figure 1). The results of calculations using the TSUNM3 model [5] were compared with measurements obtained using meteorological instruments (ultrasonic meteorological stations «Meteo-2», temperature profiler MTP-5, sodar «Volna-4M») of the Joint Use Center "Atmosphere" IAO SB RAS for various seasonal conditions [22]. Ultrasonic meteorological stations "Meteo-2" are installed at points IAO and BEC, and the temperature profiler МТР-5 at point IAO.…”

“…The aim of this work is to simulate numerically the atmospheric boundary layer parameters over a particular territory of the Siberian region as a result of the application of the mesoscale meteorological model TSUNM3 (Tomsk State University Nonhydrostatic Mesoscale Meteorology Model) [5], and to make a comparative analysis of the calculation results with observational data reached using the meteorological instruments of "Atmosphere".…”

A local observation data assimilation in mesoscale numerical weather prediction models

“…The observation results under scrutiny were used in data assimilation and in estimating the quality of numerical prediction in the TSUNM3 mesoscale model [3]. The TSUNM3 model uses a system of non-hydrostatic equations of motion and non-stationary three-dimensional equations of heat and moisture transfer in the troposphere and in the upper soil layer.…”

“…The mathematical method developed to solve the main problem in this paper is based on the optimal interpolation algorithm [1] which uses an optimal estimate of the state of the atmosphere carried out on the basis of a weighted sum of the first approximation and meteorological observations. The high-resolution Tomsk State University Nonhydrostatic Mesoscale Meteorological Model (TSUNM3) is used as a numerical model [3]. The horizontal grid of the 100 × 100 model with a resolution of 1 km covers the study area centered at a point with geographical coordinates of 56.5 o N and 85.0 o E. The vertical grid has up to 50 levels with an upper boundary at a height of 10 km.…”

Numerical Simulation of Meteorological Conditions and Air Quality above Tomsk, West Siberia

“…The purpose of this work is to test and apply the developed mesoscale model of atmospheric air quality [7,8] for the Siberian region in order to determine the most unfavorable meteorological conditions at low ambient temperatures that lead to the accumulation of pollutants near the earth's surface where the main human activity occurs.…”