Impact of Remote and Local Sources on Particulate Matter in Urban Environment

Abstract

In this paper, the impact of natural and anthropogenic sources on particulate matter with diameter less than 10 µm (PM 10) was investigated in Jeddah urban area, Saudi Arabia to identify and quantify the major particle pollution source classes. Hourly data of PM 10 and other gaseous pollutants (NO x , CO, SO 2 and O 3) and meteorological factors (temperature, relative humidity, atmospheric pressure, wind speed and wind direction) were collected at two air quality monitoring sites for the period of March 2008 to February 2009. The air mass origin was determined using 5-day backward trajectories arriving to Jeddah by using HYSPLIT model. Results show that the PM 10 Daily Limit Value was exceeded. The most frequent air masses entering Jeddah and thereby influencing PM 10 concentrations come from the East, specifically the SE and NE directions, 84% of the trajectories were originated over the Arabian Peninsula including Saudi Arabia mainland and the Arabian Gulf. The Mediterranean Sea and southern Europe were the origin source of 8% of the air mass trajectories, another 8% were originated from North Africa and Sahara Desert. The majority of PM 10 episodes were attributed to the intrusion of dust to Jeddah urban air.