Air-sea flux of CO 2 in arctic coastal waters influenced by glacial melt water and sea ice

Annual air–sea exchange ofCO2 inYoung Sound,NEGreenlandwas estimated using pCO2 surface-water measurements during summer (2006–2009) and during an ice-covered winter 2008. All surface pCO2 values were below atmospheric levels indicating an uptake of atmospheric CO2. During sea ice formation, dissolv...

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Bibliographic Details
Published in:Tellus B: Chemical and Physical Meteorology
Main Authors: Sejr, M.K., Krause-Jensen, Dorthe, Rysgaard, Søren, Sørensen, L.L., Christensen, P.B., Glud, Ronnie N.
Format: Article in Journal/Newspaper
Language:Danish
Published: 2011
Subjects:
Online Access:https://portal.findresearcher.sdu.dk/da/publications/07b1c008-4055-4d16-aedb-bc775e0b217f
https://doi.org/10.1111/j.1600-0889.2011.00540.x
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Summary:Annual air–sea exchange ofCO2 inYoung Sound,NEGreenlandwas estimated using pCO2 surface-water measurements during summer (2006–2009) and during an ice-covered winter 2008. All surface pCO2 values were below atmospheric levels indicating an uptake of atmospheric CO2. During sea ice formation, dissolved inorganic carbon (DIC) content is reduced causing sea ice to be under saturated in CO2. Approximately 1% of the DIC forced out of growing sea ice was released into the atmosphere while the remaining 99% was exported to the underlying water column. Sea ice covered the fjord 9 months a year and thereby efficiently blocked air–sea CO2 exchange. During sea ice melt, dissolution of CaCO3 combined with primary production and strong stratification of the water column acted to lower surface-water pCO2 levels in the fjord. Also, a large input of glacial melt water containing geochemically reactive carbonate minerals may contribute to the low surface-water pCO2 levels. The average annual uptake of atmospheric CO2 was estimated at 2.7 mol CO2 m−2 yr−1 or 32 g C m−2 yr−1 for the study area, which is lower than estimates from the Greenland Sea. Variability in duration of sea ice cover caused significant year-to-year variation in annual gas exchange.