Modeling of the Calm Situations in the Atmosphere of Almaty
Open Access
- 30 June 2022
- journal article
- research article
- Published by Springer Science and Business Media LLC in Asian Journal of Atmospheric Environment
- Vol. 16 (2), 14-31
- https://doi.org/10.5572/ajae.2022.007
Abstract
This article addresses modeling of the atmospheric boundary layer of the city of Almaty (Kazakhstan) in stagnant, environmentally unfavorable conditions using WRF Model. The city is located on the northern slope of Trans-Ili Alatau, where the rate of recurrence of calm and low-wind (1-2 m/sec) days reaches about 80%. All simulations were made for a period from 28.11.2016 to 05.12.2016, covering main synoptic situations of the stagnant atmosphere: the extent of Asian anticyclone, higher and lower pressure gradient fields. The model integrated three nested domains with grid sizes 9, 3 and 1 km, respectively. The initial boundary conditions were formed based on ERA5-reanalysis. Subject to the WRF model requirements, the land-use map with a standard USGS set (24 categories) was developed, to which 3 categories of the urban areas were added. The most relevant configuration of parameterization methods was selected: short-wave and long-wave radiation (Mlawer), surface layer (Monin-Obukhov similarity theory), urban area (BEP), boundary layer (Bougeault-Lacarrere), turbulence (Smagorinsky). The article demonstrates that the WRF model adequately reflects fundamental urban atmosphere patterns in the most unfavorable anticyclone periods of the autumn-winter season. It was established that the accuracy of estimates decreases with the transition to weak cyclonic activity. Based on the simulation results and remote sensing data, the territory in question is divided into four climatic zones to which a comparative method was applied; however for a detailed correlative analysis a denser network of meteorological stations is required. Calculations showed that the wind along the Ili river valley prevails in the northern part, regularly changing its western direction to eastern. Near the mountain area mountain-valley wind circulation prevails. The blocking inversion layer has a strong impact. The urban heat islands strongly depend on wind conditions. For example, a nocturnal heat island is cooled by the cold wind flow from the mountains.Keywords
Funding Information
- Ministry of Education and Science of the Republic of Kazakhstan (AP05132380/GF)
This publication has 22 references indexed in Scilit:
- WUDAPT, an efficient land use producing data tool for mesoscale models? Integration of urban LCZ in WRF over MadridUrban Climate, 2016
- On the Ability of the WRF Model to Reproduce the Surface Wind Direction over Complex TerrainJournal of Applied Meteorology and Climatology, 2013
- WRF Simulations of the Urban Circulation in the Salt Lake City Area for CO2 ModelingJournal of Applied Meteorology and Climatology, 2013
- The integrated WRF/urban modelling system: development, evaluation, and applications to urban environmental problemsInternational Journal of Climatology, 2011
- Time SeriesPublished by Elsevier BV ,2011
- Sensitivity of Low-Level Winds Simulated by the WRF Model in California’s Central Valley to Uncertainties in the Large-Scale Forcing and Soil InitializationJournal of Applied Meteorology and Climatology, 2008
- Observed and WRF-Simulated Low-Level Winds in a High-Ozone Episode during the Central California Ozone StudyJournal of Applied Meteorology and Climatology, 2008
- Radiative forcing by long‐lived greenhouse gases: Calculations with the AER radiative transfer modelsJournal of Geophysical Research: Atmospheres, 2008
- Coupling a Single-Layer Urban Canopy Model with a Simple Atmospheric Model: Impact on Urban Heat Island Simulation for an Idealized CaseJournal of the Meteorological Society of Japan. Ser. II, 2004
- Predictability of Mesoscale Atmospheric MotionsPublished by Elsevier BV ,1985