Quantification of ikaite in first and multi year sea ice

• Main Author: Kyle, Heather Marie
• Other Authors: Rysgaard, Søren (Geological Sciences), Fayek, Mostafa (Geological Sciences) Wang, Feiyue (Environment & Geography)
• Format: Master Thesis
• Language: English
• Published: 2017
• Subjects: Ikaite; Sea ice; Arctic; Carbon fluxes; Carbonate system; Climate change; Cambridge Bay; Greenland; Nunavut; Station Nord
• Online Access: http://hdl.handle.net/1993/32387

Ikaite (CaCO₃•6H₂O) is a metastable calcium carbonate mineral that forms in all types of sea ice that may play a significant role in the sea ice driven carbon pump, particularly with the increasing abundance of seasonal sea ice in the Arctic. Due to difficulties in determining its concentration and abundance, the spatial and temporal dynamics, and therefore the significance, of ikaite are poorly understood. To improve knowledge of ikaite in sea ice, a new method of quantification using dissolved inorganic carbon (DIC) analysis was developed and tested at the Sea-ice Environmental Research Facility (SERF), at Station Nord, Greenland, and at Cambridge Bay, Nunavut. Environmental parameters, including temperature, salinity, total alkalinity (TA), and DIC were also measured at all sampling sites. Ikaite concentrations ranged from 8 to 2595 μmol kg⁻¹ and were generally highest in low temperature, high salinity sea ice with high TA:DIC ratios. Results indicate that the new method of ikaite quantification is an effective technique that can be used in the future to improve understanding of ikaite and its role in carbon dynamics in ice covered seas. October 2017