Brief Communication: Ikaite (CaCO 3 ·6H 2 O) discovered in Arctic sea ice

• Published in: The Cryosphere
• Main Authors: M. A. Granskog, S. Gerland, C. Uhlig, J. Göttlicher, G. Nehrke, G. S. Dieckmann, D. N. Thomas
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2010
• Subjects: Environmental sciences; GE1-350; Geology; QE1-996.5; Arctic; Antarctic; The Antarctic; Svalbard; Antarc*; Kongsfjord*; Kongsfjorden; Sea ice; The Cryosphere
• Online Access: https://doi.org/10.5194/tc-4-227-2010; https://doaj.org/article/d064237fdeff4171828a009dd3b513a0

We report for the first time on the discovery of calcium carbonate crystals as ikaite (CaCO 3 ·6H 2 O) in sea ice from the Arctic (Kongsfjorden, Svalbard) as confirmed by morphology and indirectly by X-ray diffraction as well as XANES spectroscopy of its amorophous decomposition product. This finding demonstrates that the precipitation of calcium carbonate during the freezing of sea ice is not restricted to the Antarctic, where it was observed for the first time in 2008. This observation is an important step in the quest to quantify its impact on the sea ice driven carbon cycle.