Skip to main content

IMIS

A new integrated search interface will become available in the next phase of marineinfo.org.
For the time being, please use IMIS to search available data

 

[ report an error in this record ]basket (0): add | show Print this page

Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period
Brown, K.; Miller, L.; Mundy, C.; Papakyriakou, T.; Francois, R.; Gosselin, M.; Carnat, G.; Swystun, K.; Tortell, P. (2015). Inorganic carbon system dynamics in landfast Arctic sea ice during the early-melt period. JGR: Oceans 120(5): 3542-3566. https://dx.doi.org/10.1002/2014JC010620
In: Journal of Geophysical Research-Oceans. AMER GEOPHYSICAL UNION: Washington. ISSN 2169-9275; e-ISSN 2169-9291, more
Peer reviewed article  

Available in  Authors 

Keyword
    Marine/Coastal
Author keywords
    sea ice; carbon cycling; CO2; brines; stable isotopes; Arctic Ocean

Authors  Top 
  • Brown, K.
  • Miller, L.
  • Mundy, C.
  • Papakyriakou, T.
  • Francois, R.
  • Gosselin, M.
  • Carnat, G., more
  • Swystun, K.
  • Tortell, P.

Abstract
    We present the results of a 6 week time series of carbonate system and stable isotope measurements investigating the effects of sea ice on air-sea CO2 exchange during the early melt period in the Canadian Arctic Archipelago. Our observations revealed significant changes in sea ice and sackhole brine carbonate system parameters that were associated with increasing temperatures and the buildup of chlorophyll a in bottom ice. The warming sea-ice column could be separated into distinct geochemical zones where biotic and abiotic processes exerted different influences on inorganic carbon and pCO(2) distributions. In the bottom ice, biological carbon uptake maintained undersaturated pCO(2) conditions throughout the time series, while pCO(2) was supersaturated in the upper ice. Low CO2 permeability of the sea ice matrix and snow cover effectively impeded CO2 efflux to the atmosphere, despite a strong pCO(2) gradient. Throughout the middle of the ice column, brine pCO(2) decreased significantly with time and was tightly controlled by solubility, as sea ice temperature and in situ melt dilution increased. Once the influence of melt dilution was accounted for, both CaCO3 dissolution and seawater mixing were found to contribute alkalinity and dissolved inorganic carbon to brines, with the CaCO3 contribution driving brine pCO(2) to values lower than predicted from melt-water dilution alone. This field study reveals a dynamic carbon system within the rapidly warming sea ice, prior to snow melt. We suggest that the early spring period drives the ice column toward pCO(2) undersaturation, contributing to a weak atmospheric CO2 sink as the melt period advances.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors