Grantee Research Project Results

Final Report: Tracer Studies of Sulfur Dioxide Oxidation in Clouds

EPA Grant Number: R823422
Title: Tracer Studies of Sulfur Dioxide Oxidation in Clouds
Investigators: Husain, Liaquat
Institution: The State University of New York
EPA Project Officer: Hahn, Intaek
Project Period: September 1, 1995 through August 31, 1998
Project Amount: $335,659
RFA: Exploratory Research - Chemistry and Physics of Air (1995) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Air , Safer Chemicals

Objective:

The primary objective of this project was to quantify the oxidation of sulfur dioxide in cloud droplets in the Northeastern United States.

Summary/Accomplishments (Outputs/Outcomes):

We have reported experimental evidence showing a sharp decrease in aerosol levels in northeastern United States caused by reduction in SO₂ emissions in the midwestern United States. Continuous measurements were made at Whiteface Mountain in the Adirondack region of New York State from 1979 to 1996 and Mayville in the western part of the State from 1983 to 1996. The results show that from 1981 to 1991 the concentration remained the same within experimental uncertainties. Similarly, slight reductions occurred in SO₂ emissions in the midwest during this period. However, reductions of nearly 47 percent in at Whiteface Mt and 30 percent at Mayville, compared to 1981-91 period, were observed during 1995 and 1996. This sharp decline in concentrations coincided with a 36 percent reduction in SO₂ emissions in the midwest. Linear relationship between and total S (sum of S present as SO₂ + ) and the midwestern SO₂ emissions was observed for the entire period at the two sites, 530 km apart. The mean ratio of concentrations to SO₂ emissions for the eighteen year period at Whiteface Mountain is 0.11 + 0.014 and for thirteen years at Mayville is 0.23 + 0.014 µg /m³ per 10³ metric tons SO₂ emitted per day. The data suggest that the observed relationship could be used to predict decreases in atmospheric levels based on SO₂ emissions several years hence. Furthermore, it appears feasible to develop an empirical source-receptor relationship if similar data were acquired from a network of strategically located sampling sites.

Journal Articles on this Report : 2 Displayed | Download in RIS Format

Publications Views

Other project views:	All 2 publications	2 publications in selected types	All 2 journal articles

Publications

Type	Citation	Project	Document Sources
Journal Article	Dutkiewicz VA, Das M, Husain L. The relationship between regional SO2 emissions and downwind aerosol sulfate concentrations in the northeastern US. Atmospheric Environment 2000;34(11):1821-1832.	R823422 (Final)	not available
Journal Article	Husain L, Dutkiewicz VA, Das M. Evidence for decrease in atmospheric sulfur burden in the eastern United States caused by reduction in SO2 emissions. Geophysical Research Letters 1998;25(7):967-970.	R823422 (Final)	not available

Supplemental Keywords:

air, ambient air, atmosphere, oxidants, sulfates, H2O2, SO2, environmental chemistry, monitoring, measurement methods, northeast, New York, NY, Region 2., Air, Scientific Discipline, Geographic Area, EPA Region, State, Chemistry, Environmental Chemistry, Engineering, Chemistry, & Physics, Physics, aerosol particles, meterology, ambient aerosol, tracer studies, source receptor relationship, fate and transport, field monitoring, sulfur dioxide absorption, New York (NY), gas-phase oxidation, acid rain, anthropogenic stress

Progress and Final Reports:

Original Abstract

1996

1997