Engineering Commons^™

Intraurban Variability Of Ambient Particulate Matter, Varun Yadav

All Theses and Dissertations (ETDs)

An understanding of spatial and temporal variability in ambient particulate matter: PM) is important for effective air quality management and for assessing potential exposure misclassification in epidemiological and exposure studies used to support health-based standards. Spatiotemporal variability of PM in urban areas can be influenced by many factors, such as local sources of primary PM; source locations and their emission profiles; topographic barriers; meteorological patterns; behavior of semi-volatile components; and measurement errors. Intraurban variability is often gauged by conducting measurements at a network of monitoring stations across the region of interest. While certain statistical metrics are commonly used and interpreted …

Effects Of Nitrogen Deposition And Empirical Nitrogen Critical Loads For Ecoregions Of The United States, Linda Pardo, Mike Fenn, Christine Goodale, Linda. Geiser, Charles Driscoll, Edith Allen, Jill Baron, Roland Bobbink, Williams Bowman, Christopher Clark, Bridget Emmett, Frank Gilliam, Tara Greaver, Sharon Hall, Erik Lilleskov, Lingli Liu, Jason Lynch, Knute Nadelhoffer, Steven Perakis, Molly Robin-Abbott, John Stoddard, Kathleen Weathers, Robin Dennis

Frank S. Gilliam

Human activity in the last century has led to a significant increase in nitrogen (N) emissions and atmospheric deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the deposition of pollution that would be harmful to ecosystems is the determination of critical loads. A critical load is defined as the input of a pollutant below which no detrimental ecological effects occur over the long-term according to present knowledge.

The objectives of this project were to synthesize …