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Title: Changes in Atmospheric Aqueous Chemistry at Whiteface Mountain: Shifting focus from Acid rain
Whiteface Mountain is home to an historical cloud water monitoring site, with cloud water collection dating as far back as the 1970s. The cloud collection was largely founded to investigate and monitor the growing problems associated with acid deposition with regular monitoring beginning in 1994 and continuing to this date. Findings from sites like Whiteface Mountain help contributed to the Clean Air Act Amendments of 1990s which contributed to significant reductions in emissions of SO2 and NOx, leading to significant decreases in SO4 and NO3 concentrations in both Whiteface Mountain cloud water and NADP National Trend Network sites nationwide. Recently, a significant milestone for acid deposition was reached at WFM: median concentrations of Ca were higher than SO4 concentrations, with a correspondingly high median pH of 6.3 in 2020. Additionally, there are increasing trends in Ca, K, Mg, and potentially total organic carbon, while NH4 and NO3 exhibit no trend. These changes point to a considerably different chemical system that have important implications for not only acid deposition but for nitrogen deposition, base cation deposition, and secondary organic and inorganic aerosol formation. This presentation will discuss the significant changes to major base cations and organic carbon (total organic carbon and organic acids) and their inter-relationships. Statistical techniques such as factor analysis and positive matrix factorization will be used for source apportionment. Comparisons of cloud composition will be made with regional NADP National Trend Network sites to investigate the potential changes in base cation deposition. Lastly, future implications will be discussed for air quality, ecosystem health, and climate.  more » « less
Award ID(s):
1945563
PAR ID:
10313982
Author(s) / Creator(s):
Date Published:
Journal Name:
National Acid Deposition Program (NADP) Scientific Symposium & Fall Meeting
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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