| 1. |
- Breitbarth, Eike, et al.
(author)
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Iron biogeochemistry across marine systems – progress from the past decade
- 2010
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In: Biogeosciences. - 1726-4170. ; 7, s. 1075-1097
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Research review (peer-reviewed)abstract
- Based on an international workshop (Gothenburg, 14–16 May 2008), this review article aims to combine interdisciplinary knowledge from coastal and open ocean research on iron biogeochemistry. The major scientific findings of the past decade are structured into sections on natural and artificial iron fertilization, iron inputs into coastal and estuarine systems, colloidal iron and organic matter, and biological processes. Potential effects of global climate change, particularly ocean acidification, on iron biogeochemistry are discussed. The findings are synthesized into recommendations for future research areas.
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| 2. |
- Abbas, Zareen, 1962, et al.
(author)
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Monte Carlo simulation of the dissociation constants of CO2 in 0 to 1 molal sodium chloride between 0 and 25 °C
- 2013
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In: Marine Chemistry. - : Elsevier BV. - 0304-4203. ; 150:1, s. 1-10
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Journal article (peer-reviewed)abstract
- Stoichiometric dissociation constants of the carbon dioxide system in NaCl solution between 0 and 1 mol and 0 to 25 °C were estimated by Monte Carlo (MC) simulations, and compared with Pitzer calculations and experimental measurements. The MC simulations used experimentally determined dielectric constants of water at different temperatures, and optimal agreement with the experimental data and Pitzer calculations was achieved by adjusting the ionic radii. This simple procedure resulted in effective ionic radii which were further used to simulate the activity coefficients of salt mixtures. The first and second stoichiometric dissociation constants of carbonic acid in NaCl solution (pK1⁎ and pK2⁎) were estimated from the MC-derived activity coefficients of mixed salts in NaCl. The MC results are in good agreement with the experimental data as well as with the Pitzer calculations. This study shows that Monte Carlo simulations in the temperature and ionic strength range relevant to seawater can provide pK values of the same quality as Pitzer calculations, and constitutes the first step in developing a temperature-dependent MC model for seawater. While MC calculations require greater computing resources, the number of parameters derived by fitting to thermodynamic data is substantially smaller than for Pitzer calculations.
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| 3. |
- Hassellöv, Ida-Maja, 1974, et al.
(author)
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Shipping contributes to ocean acidification
- 2013
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In: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 40:11, s. 2731-2736
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Journal article (peer-reviewed)abstract
- The potential effect on surface water pH of emissions of SOX and NOX from global ship routes is assessed. The results indicate that regional pH reductions of the same order of magnitude as the CO2-driven acidification can occur in heavily trafficked waters. These findings have important consequences for ocean chemistry, since the sulfuric and nitric acids formed are strong acids in contrast to the weak carbonic acid formed by dissolution of CO2. Our results also provide background for discussion of expanded controls to mitigate acidification due to these shipping emissions.
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