کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
975025 1480146 2015 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Statistical persistence of air pollutants (O3,SO2,NO2 and PM10) in Mexico City
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات فیزیک ریاضی
پیش نمایش صفحه اول مقاله
Statistical persistence of air pollutants (O3,SO2,NO2 and PM10) in Mexico City
چکیده انگلیسی


• Air-pollutants in Mexico City exhibit long-range persistence.
• Persistence shows scale and time dependences.
• Environmental (daily and yearly) and business (weekly) cycles affect the persistence characteristics.
• Persistence is explained from the self-organized critically framework.

The rescaled range (R/S)(R/S) analysis was used for analyzing the statistical persistence of air pollutants in Mexico City. The air-pollution time series consisted of hourly observations of ozone, nitrogen dioxide, sulfur dioxide and particulate matter obtained at the Mexico City downtown monitoring station during 1999–2014. The results showed that long-range persistence is not a uniform property over a wide range of time scales, from days to months. In fact, although the air pollutant concentrations exhibit an average persistent behavior, environmental (e.g., daily and yearly) and socio-economic (e.g., daily and weekly) cycles are reflected in the dependence of the persistence strength as quantified in terms of the Hurst exponent. It was also found that the Hurst exponent exhibits time variations, with the ozone and nitrate oxide concentrations presenting some regularity, such as annual cycles. The persistence dynamics of the pollutant concentrations increased during the rainy season and decreased during the dry season. The time and scale dependences of the persistence properties provide some insights in the mechanisms involved in the internal dynamics of the Mexico City atmosphere for accumulating and dissipating dangerous air pollutants. While in the short-term individual pollutants dynamics seems to be governed by specific mechanisms, in the long-term (for monthly and higher scales) meteorological and seasonal mechanisms involved in atmospheric recirculation seem to dominate the dynamics of all air pollutant concentrations.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica A: Statistical Mechanics and its Applications - Volume 427, 1 June 2015, Pages 202–217
نویسندگان
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