Quantification of the Dry Deposition Flux and Air Water Exchange of Reactive and Reduced Nitrogen

EPA Grant Number: R826647
Title: Quantification of the Dry Deposition Flux and Air Water Exchange of Reactive and Reduced Nitrogen
Investigators: Holsen, Thomas M.
Institution: Clarkson University , Illinois Institute of Technology
Current Institution: Clarkson University
EPA Project Officer: Lasat, Mitch
Project Period: October 1, 1998 through September 30, 2001
Project Amount: $309,104
RFA: Exploratory Research - Environmental Chemistry (1998) RFA Text |  Recipients Lists
Research Category: Sustainability , Land and Waste Management , Air , Engineering and Environmental Chemistry

Description:

This research project will use a newly developed instrument, the Water Surface Sampler (WSS), to directly measure the dry deposition flux of reactive and reduced nitrogen. These species are responsible for acidification and eutrophication of many of our waterways. The specific objectives of the research are to: 1) use the Awater surface sampler@ to directly measure the dry deposition of both reactive and reduced nitrogen that exist in both the gas and particulate phases, 2) characterize the collection properties of the water surface for these compounds 3) develop techniques to analyze the data collected and 4) compare this technique to indirect methods currently being developed by NOAA.

Approach:

Dry deposition samples will be collected with both an aerodynamically smooth water surface and a knife-edge greased surrogate surface. These samples will be collected during periods of no rain or threat of rain. Ambient reactive and reduced nitrogen measurements and meteorological data will be obtained concurrently at the site. Particulate reactive and reduced nitrogen fluxes will be measured by extracting and analyzing samples collected on specially prepared media contained on a knife-edge surrogate surface. Dry deposition samples from the water surface, which will collect both particulate and gas phase deposition, will also be analyzed for reactive and reduced nitrogen. This work will initially be performed at IIT in Chicago during the first year of the project. During the second year measurements will be performed at the Chesapeake Biological Station (Univ of Maryland) in Solomons, MD with the help of Professor Joel Baker. Measurements will also be made alongside gradient methods currently under development by Bruce Hicks and his team at the NOAA Air Resources Laboratory.

Expected Results:

Specifically, these measurements will be used to: 1) determine which forms of nitrogen contribute to total N deposition to the Chesapeake Bay, 2) determine the importance of particulate and gas phase N deposition, 3) provide deposition velocity measurements to validate the models currently being used, 4) estimate atmospheric loadings to the Bay due to dry deposition and 5) provide information that can be used to determine the relative atmosphere loadings of N to the Bay. The results will be used to better understand how atmospheric nitrogen species affect coastal ecosystems and the related policy options to manage this resource, and aid in a cross-media approach needed to manage the atmospheric deposition and loadings of nitrogen species. Projections for the coming decades estimate that the atmosphere will become a more significant source of nitrogen loadings to coastal areas with anticipated increases in population and land development resulting from more mobile and new power plant emissions. A better understanding of atmospheric dry deposition is needed to understand the inputs and fates of reactive and reduced nitrogen to lakes, coastal regions and terrestrial systems and to describe the short and long range transport of air pollutants and their global behavior.

Publications and Presentations:

Publications have been submitted on this project: View all 1 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 1 journal articles for this project

Supplemental Keywords:

chemical transport, environmental chemistry, nitrogen oxides, modeling, monitoring, Chesapeake Bay., RFA, Scientific Discipline, Air, Water, Nutrients, particulate matter, Environmental Chemistry, Air Deposition, Engineering, Chemistry, & Physics, fate and transport, eutrophication, hydrological stability, dry deposition studies, environmental monitoring, reactive contaminant transport, particulates, aerosol particles, atmospheric particles, gas phase nitrogen deposition, chemical transport, chemical transport modeling, atmospheric nitrogen deposits, nutrient stress, chemical kinetics, nutrient cycling, meterology, atmospheric loading, water surface sampler, atmospheric deposition

Progress and Final Reports:

  • 1999 Progress Report
  • 2000
  • Final