Applied Research in Geographical Sciences

Applied Research in Geographical Sciences

Investigation of nitrogen dioxide behavior in Mashhad and its relationship with Meteorological Parameters

Authors
1 University of Zanjan
2 University of Isfahan
Abstract
Urban development and air pollution are among the most important issues related to climate. The expansion of urbanization and urban development, population growth, industrial development and excessive use of fossil fuels significantly increased air pollution and it is more than the capacity of the environment. In our country, the emissions of air pollutants in some metropolitan areas have reached a dangerous level, Mashhad is considered to be the most polluted cities of the country in some days of the year. Nitrogen dioxide is one of the indicators of air pollution. In this study, the OMI data and atmospheric parameters such as wind, surface temperature, and horizontal visibility data for the period from 2004 to May 2016 were used to investigate the air pollution in Mashhad. The results show that the maximum (minimum) nitrogen dioxide levels occur in the cold (hot) season. The highest amount of nitrogen dioxide in January is equal to 5.56 × 1015 molec/cm2 and its lowest value in September is 4.18 × 1015 molec/cm2. Standard deviation of nitrogen dioxide also indicates that the greatest changes occur in cold seasons. Also, the results showed that the dominant wind in the city of Mashhad is from the south, and most of the winds are slow. Correlation coefficient of nitrogen dioxide with wind and surface temperature is -0.36 and -0.57, respectively, which shows the higher importance of temperature in nitrogen dioxide changes in Mashhad city. The correlation coefficient of nitrogen dioxide with horizontal visibility is -0.15, which indicates that with increasing nitrogen dioxide contamination, horizontal visibility decreases. Spectral analysis of least squares of the six and twelve-month periods of rotation was observed, they were also statistically significant. After eliminating the significant components of the time series of the average monthly nitrogen dioxide, the trend was calculated. The amount of nitrogen dioxide in each year for Mashhad was 2.41 × 1013 molec/cm2.
Keywords

Ghude, S. D., Van der A, R. J., Beig, G., Fadnavis, S. (2009). Trends in NO2 over the major global hotspot.
https://aura.gsfc.nasa.gov/omi.htm.
Lamsal, L. N., Duncan, B. N., Yoshida, Y., Krotkov, N. A., Pickering, k. E., Streets, D. G., Lu, Z. (2015). US NO2 trends (2005-2013): EPA Air Quality System (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI). Atmospheric Environment, 110, 130-143.
Pagiatakis, S. D. (1999). Stochastic significance of peaks in the least- squares spectrum. Journal of Geodesy, 73(2), 67-78.
Samet JM and et al. The National Morbidity, Mortality and Air Pollution Study. Health Effects Institute.
Schneider, P., Lahoz, W. A., van der A, R (2015). Recent satellite-based trends of tropospheric nitrogen dioxide over large urban agglomerations worldwide. Atmospheric Chemistry and Physics, 15(3), 1205-1220.
Shepard, Ch.(2004). Sea surface temperature 1871-2099 in 14 cells around the United Kingdom. Marine Pollution Bulletin.
Van Der A, R. J., Peters, D. H. M. U., Eskes, H., Boersma, K. F., Van Roozendael, M., De Smedt, I., kelder, H. M (2006). Detection of the trend and seasonal variation in tropospheric NO2 over China. Journal of Geophysical Research: Atmospheres, 111(D12).
Vanicek, P. (1971). Further development and properties of the spectral analysis by leastsquares. Astrophysics and Space Science, 12(1), 10-33.
www.irimo.ir.
Zhang, R., Tie, X., and Bond, D. W. (2003). Impacts of anthropogenic and natural NOx sources over the U.S. on tropospheric chemistry, Proceedings of the National Academy of Sciences of the United States of America (PNAS), 100, 1505-1509.Pagiatakis, S. D. (1999). Stochastic significance of peaks in the least- squares spectrum. Journal of Geodesy, 73(2), 67-78.
Zhou, Y., Brunner, D., Hueglin, C., Henne, S. and Staehelin, J.(2012). Changes in OMI tropospheric NO2 columns over Europe from 2004 to 2009 and the influence of meteorological variability, Atmospheric Environment, 46, 482-495.