title: Time series analysis of air pollutants in Beirut, Lebanon.
abstract: This study reports for the first time a time series analysis of daily urban air pollutant levels (CO, NO, NO2, O3, PM10, and SO2) in Beirut, Lebanon. The study examines data obtained between September 2005 and July 2006, and their descriptive analysis shows long-term variations of daily levels of air pollution concentrations. Strong persistence of these daily levels is identified in the time series using an autocorrelation function, except for SO2. Time series of standardized residual values (SRVs) are also calculated to compare fluctuations of the time series with different levels. Time series plots of the SRVs indicate that NO and NO2 had similar temporal fluctuations. However, NO2 and O3 had opposite temporal fluctuations, attributable to weather conditions and the accumulation of vehicular emissions. The effects of both desert dust storms and airborne particulate matter resulting from the Lebanon War in July 2006 are also discernible in the SRV plots.
authors.affiliation: Département de Physique, F.S., Université Saint-Joseph, Campus des sciences et technologies, Mar Roukos, Mkalles. B.P. 11-514 Riad el Solh, Beirut, 11072050, Lebanon, wehbeh.farah@usj.edu.lb.
authors.forename: Wehbeh
authors.initials: W
authors.lastname: Farah
authors.forename: Myriam Mrad
authors.initials: MM
authors.lastname: Nakhlé
authors.forename: Maher
authors.initials: M
authors.lastname: Abboud
authors.forename: Isabella
authors.initials: I
authors.lastname: Annesi-Maesano
authors.forename: Rita
authors.initials: R
authors.lastname: Zaarour
authors.forename: Nada
authors.initials: N
authors.lastname: Saliba
authors.forename: Georges
authors.initials: G
authors.lastname: Germanos
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Gerard
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis / Q000706:statistics & numerical data*; D004784:Environmental Monitoring; D007861:Lebanon; D052638:Particulate Matter / Q000032:analysis; D001335:Vehicle Emissions / Q000032:analysis; D014887:Weather
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D001335:Vehicle Emissions