The Contribution of Sulfate and Nitrate to Atmospheric Fine Particles During Winter Inversion Fogs in Cache Valley, Utah

• Published in: Journal of the Air & Waste Management Association (1995) Vol. 47; no. 2; pp. 167 - 175
• Main Authors: Mangelson, Nolan F., Lewis, Laura, Joseph, Jyothi M., Cui, Wenxuan, Machir, James, Eatough, Delbert J., Rees, Lawrence B., Wilkerson, Tom, Jensen, Don T.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Pittsburgh, PA Taylor & Francis Group 01-02-1997; Air & Waste Management Association
• Subjects: Applied sciences; Atmospheric pollution; Exact sciences and technology; Pollutants physicochemistry study: properties, effects, reactions, transport and distribution; Pollution; United States; North America; Utah; America; Suspended particle; Chemical analysis; Pollution source; Aerosols; Atmospheric inversion; Air pollution; Nitrates; Sampling; Sulfates; Fog
• ISSN: 1096-2247; 2162-2906
• DOI: 10.1080/10473289.1997.10464429

Air pollutants were collected in Logan, Cache County, UT, in February 1993 during two periods of atmospheric inversion accompanied by fog. The following atmospheric species were determined: (1) gaseous SO
2
, NO
2
(semi-quantitatively),HNO3, NH3, and HF; (2) fine particulate SO
4
=
, NO
3
-
, NH
4
+
, F-, H
+
, C, Si, S, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Pb, Se, Br, and Sr, and; (3) fine particulate mass, which was calculated. The major components of fine particulate matter were carbonaceous material, ammonium nitrate, and ammonium sulfate, while the soil component was small. Calculated, fine particulate mass averaged 80 μg/m
3
and reached concentrations as high as 120 μg/m
3
. SO
2
/So
x
and NO
2
/NO
y
mole ratios generally varied between 0.2 and 0.1 during inversions. These ratios also showed moderate but consistent diurnal patterns. The emission inventory for Cache County indicates sources of SO
2
and NO
x
but not significant amounts of primary sulfate and nitrate. The observations reported here indicate there is significant conversion of SO
2
and NO
x
in the presence of excess oxidants to sulfuric and nitric acid that are neutralized by excess ammonia.