A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Aqueous Elemental Mercury Production versus Mercury Inventories in the Lake Michigan Airshed: Deciphering the Spatial and Diel Controls of Mercury Gradients in Air and Water
https://orcid.org/0000-0003-2806-1895
https://orcid.org/0000-0003-4430-5319
https://orcid.org/0000-0003-1964-5020
Atmospheric delivery of mercury (Hg) is important to the Upper Great Lakes, and understanding gaseous Hg exchange between surface water and air is critical to predicting the effects of declining mercury emissions. Speciated atmospheric Hg, dissolved gaseous Hg (DGM), and particulate and filter passing total Hg were measured on a cruise in Lake Michigan. Low mercury levels reflected pristine background conditions, especially in offshore regions. In the atmosphere, reactive and particle-associated fractions were low (1.0 ± 0.5%) compared to gaseous elemental Hg (1.34 ± 0.14 ng m–3) and were elevated in the urbanized southern basin. DGM was supersaturated, ranging from 17.5 ± 4.8 pg L–1 (330 ± 80%) in the main lake to 33.2 ± 2.4 pg L–1 (730 ± 70%) in Green Bay. Diel cycling of surface DGM showed strong Hg efflux during the day due to increased winds, and build-up at night from continued DGM production. Epilimnetic DGM is formed from photochemical reduction, while hypolimnetic DGM originates from biological Hg reduction. We found that DGM concentrations were greatest below the thermocline (30.8 ± 13.6 pg L–1), accounting for 68–92% of the total DGM in Lake Michigan, highlighting the importance of nonphotochemical reduction in deep stratified lakes.
We examined when and where gaseous mercury is produced in Lake Michigan to infer controlling processes and declines in mercury concentrations over the past 25 years.
Aqueous Elemental Mercury Production versus Mercury Inventories in the Lake Michigan Airshed: Deciphering the Spatial and Diel Controls of Mercury Gradients in Air and Water
https://orcid.org/0000-0003-2806-1895
https://orcid.org/0000-0003-4430-5319
https://orcid.org/0000-0003-1964-5020
Atmospheric delivery of mercury (Hg) is important to the Upper Great Lakes, and understanding gaseous Hg exchange between surface water and air is critical to predicting the effects of declining mercury emissions. Speciated atmospheric Hg, dissolved gaseous Hg (DGM), and particulate and filter passing total Hg were measured on a cruise in Lake Michigan. Low mercury levels reflected pristine background conditions, especially in offshore regions. In the atmosphere, reactive and particle-associated fractions were low (1.0 ± 0.5%) compared to gaseous elemental Hg (1.34 ± 0.14 ng m–3) and were elevated in the urbanized southern basin. DGM was supersaturated, ranging from 17.5 ± 4.8 pg L–1 (330 ± 80%) in the main lake to 33.2 ± 2.4 pg L–1 (730 ± 70%) in Green Bay. Diel cycling of surface DGM showed strong Hg efflux during the day due to increased winds, and build-up at night from continued DGM production. Epilimnetic DGM is formed from photochemical reduction, while hypolimnetic DGM originates from biological Hg reduction. We found that DGM concentrations were greatest below the thermocline (30.8 ± 13.6 pg L–1), accounting for 68–92% of the total DGM in Lake Michigan, highlighting the importance of nonphotochemical reduction in deep stratified lakes.
We examined when and where gaseous mercury is produced in Lake Michigan to infer controlling processes and declines in mercury concentrations over the past 25 years.
Aqueous Elemental Mercury Production versus Mercury Inventories in the Lake Michigan Airshed: Deciphering the Spatial and Diel Controls of Mercury Gradients in Air and Water
https://orcid.org/0000-0003-2806-1895
https://orcid.org/0000-0003-4430-5319
https://orcid.org/0000-0003-1964-5020
Atmospheric delivery of mercury (Hg) is important to the Upper Great Lakes, and understanding gaseous Hg exchange between surface water and air is critical to predicting the effects of declining mercury emissions. Speciated atmospheric Hg, dissolved gaseous Hg (DGM), and particulate and filter passing total Hg were measured on a cruise in Lake Michigan. Low mercury levels reflected pristine background conditions, especially in offshore regions. In the atmosphere, reactive and particle-associated fractions were low (1.0 ± 0.5%) compared to gaseous elemental Hg (1.34 ± 0.14 ng m–3) and were elevated in the urbanized southern basin. DGM was supersaturated, ranging from 17.5 ± 4.8 pg L–1 (330 ± 80%) in the main lake to 33.2 ± 2.4 pg L–1 (730 ± 70%) in Green Bay. Diel cycling of surface DGM showed strong Hg efflux during the day due to increased winds, and build-up at night from continued DGM production. Epilimnetic DGM is formed from photochemical reduction, while hypolimnetic DGM originates from biological Hg reduction. We found that DGM concentrations were greatest below the thermocline (30.8 ± 13.6 pg L–1), accounting for 68–92% of the total DGM in Lake Michigan, highlighting the importance of nonphotochemical reduction in deep stratified lakes.
We examined when and where gaseous mercury is produced in Lake Michigan to infer controlling processes and declines in mercury concentrations over the past 25 years.
Aqueous Elemental Mercury Production versus Mercury Inventories in the Lake Michigan Airshed: Deciphering the Spatial and Diel Controls of Mercury Gradients in Air and Water
Lepak, Ryan F. (author) / Tate, Michael T. (author) / Ogorek, Jacob M. (author) / DeWild, John F. (author) / Peterson, Benjamin D. (author) / Hurley, James P. (author) / Krabbenhoft, David P. (author)
ACS ES&T Water ; 1 ; 719-727
2021-03-12
Article (Journal)
Electronic Resource
English
Assessment of Exposure to Mercury Vapor in Indoor Air from Spilled Elemental Mercury
| British Library Online Contents | 2004