Using detailed elemental analysis of airborne particulate matter to quantify local and global dust sources
Shankar Chellam
Department of Civil and Environmental Engineering
University of Houston
Abstract
Airborne particulate matter contributes to haze, acid rain, global climate change, asthma and other respiratory ailments, cardiopulmonary disease, and decreased life expectancy. For the past approximately 10-years, we have successfully quantified emissions from petroleum refining operations, tailpipe and non-tailpipe emissions from light-duty motor vehicles, and formation of secondary sulfate aerosols. More recently, we have demonstrated that long-range transport of dust from North Africa occasionally increases fine and coarse particulate matter concentrations in Houston. This was accomplished by systematic and highly sensitive measurements of representative elements as well as transition and lanthanoid metals in ambient urban aerosols and source samples using inductively coupled plasma – mass spectrometry. The seminar will cover two topics: (1) the routine and episodic atmospheric enrichment of rare earth elements in Houston that was traced to crude oil cracking catalysts and (2) trans-Atlantic transport of dust from the Sahara-Sahel region which occasionally increases ambient aerosol concentrations in Houston.