TY - JOUR
T1 - Acidification of East Siberian Arctic Shelf waters through addition of freshwater and terrestrial carbon
AU - Semiletov, Igor Petrovich
AU - Pipko, Irina Ivanovna
AU - Gustafsson, Örjan
AU - Anderson, Leif G.
AU - Sergienko, Valentin
AU - Pugach, Svetlana Petrovna
AU - Dudarev, Oleg Victorovich
AU - Charkin, Alexander
AU - Gukov, Alexander
AU - Bröder, Lisa
AU - Andersson, August
AU - Spivak, Eduard
AU - Shakhova, Natalia Evgenievna
PY - 2016/5/1
Y1 - 2016/5/1
N2 - Ocean acidification affects marine ecosystems and carbon cycling, and is considered a direct effect of anthropogenic carbon dioxide uptake from the atmosphere. Accumulation of atmospheric CO2 in ocean surface waters is predicted to make the ocean twice as acidic by the end of this century. The Arctic Ocean is particularly sensitive to ocean acidification because more CO2 can dissolve in cold water. Here we present observations of the chemical and physical characteristics of East Siberian Arctic Shelf waters from 1999, 2000-2005, 2008 and 2011, and find extreme aragonite undersaturation that reflects acidity levels in excess of those projected in this region for 2100. Dissolved inorganic carbon isotopic data and Markov chain Monte Carlo simulations of water sources using salinity and Î 18 O data suggest that the persistent acidification is driven by the degradation of terrestrial organic matter and discharge of Arctic river water with elevated CO2 concentrations, rather than by uptake of atmospheric CO2. We suggest that East Siberian Arctic Shelf waters may become more acidic if thawing permafrost leads to enhanced terrestrial organic carbon inputs and if freshwater additions continue to increase, which may affect their efficiency as a source of CO2.
AB - Ocean acidification affects marine ecosystems and carbon cycling, and is considered a direct effect of anthropogenic carbon dioxide uptake from the atmosphere. Accumulation of atmospheric CO2 in ocean surface waters is predicted to make the ocean twice as acidic by the end of this century. The Arctic Ocean is particularly sensitive to ocean acidification because more CO2 can dissolve in cold water. Here we present observations of the chemical and physical characteristics of East Siberian Arctic Shelf waters from 1999, 2000-2005, 2008 and 2011, and find extreme aragonite undersaturation that reflects acidity levels in excess of those projected in this region for 2100. Dissolved inorganic carbon isotopic data and Markov chain Monte Carlo simulations of water sources using salinity and Î 18 O data suggest that the persistent acidification is driven by the degradation of terrestrial organic matter and discharge of Arctic river water with elevated CO2 concentrations, rather than by uptake of atmospheric CO2. We suggest that East Siberian Arctic Shelf waters may become more acidic if thawing permafrost leads to enhanced terrestrial organic carbon inputs and if freshwater additions continue to increase, which may affect their efficiency as a source of CO2.
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U2 - 10.1038/ngeo2695
DO - 10.1038/ngeo2695
M3 - Article
AN - SCOPUS:84971272978
VL - 9
SP - 361
EP - 365
JO - Nature Geoscience
JF - Nature Geoscience
SN - 1752-0894
IS - 5
ER -