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| Titel |
Changing Atmospheric Acidity and the Oceanic Solubility of Nutrients |
| VerfasserIn |
Alex Baker, Manmohan Sarin, Robert Duce, Tim Jickells, Maria Kanakidou, Stelios Myriokefalitakis, Akinori Ito, David Turner, Natalie Mahowald, Rob Middag, Cecile Guieu, Yuan Gao, Peter Croot, Rachel Shelley, Morgane Perron |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250144755
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| Publikation (Nr.) |
 EGU/EGU2017-8619.pdf |
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| Zusammenfassung |
| The atmospheric deposition of nutrients to the ocean is known to play a significant role in the
marine carbon cycle. The impact of such deposition is dependent on the identity of the
nutrient in question (e.g., N, P, Fe, Co, Zn, Ni, Cd), the location of the deposition, and the
bioavailability of the deposited nutrient. Bioavailability is largely governed by the chemical
speciation of a nutrient and, in general, insoluble species are not bioavailable. For Fe and P
(and perhaps the other nutrient trace metals) solubility increases during transport through the
atmosphere. The causes of this increase are complex, but interactions of aerosol particles with
acids appears to play a significant role. Emissions of acidic (SO2 and NOx) and
alkaline (NH3) gases have increased significantly since the Industrial Revolution, with
a net increase in atmospheric acidity. This implies that Fe and P solubility may
also have increased over this time period, potentially resulting in increased marine
productivity. More recently, pollution controls have decreased emissions of SO2 from some
regions and further reductions in SO2 and NOx are likely in the future. Emissions of
NH3 are much more difficult to control however, and are projected to stabilise or
increase slightly to the end of this century. Future anthropogenic emissions are
thus likely to change the acidity of the atmosphere downwind of major urban /
industrial centres, with potential consequences for the supply of soluble nutrients to the
ocean.
To address these issues UN/GESAMP Working Group 38, The Atmospheric Input of
Chemicals to the Ocean, is convening a workshop on this topic at the University of East
Anglia in February, 2017. The goals of this workshop are to review and synthesize the current
scientific information on the solubility of aerosol-associated key biogeochemical elements,
the biogeochemical controls on aerosol solubility, and the pH sensitivity of those controls;
to consider the likely changes in solubility of key species into the future and the
potential biogeochemical consequences of such changes; and to identify the key future
research needs to reduce uncertainties in predictive capability in this area. The
results, conclusions, and recommendations of this workshop will be presented. |
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