Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice
Cracks are common and natural features of sea ice formed in the polar oceans. In this study, a sea ice crack in flooded, multiyear, land-fast Antarctic sea ice was examined to assess its influence on biological productivity and the transport of nutrients and microalgae into the upper layers of neigh...
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fthokunivhus:oai:eprints.lib.hokudai.ac.jp:2115/71232 2023-09-05T13:13:48+02:00 Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice Nomura, Daiki Aoki, Shigeru Simizu, Daisuke Iida, Takahiro http://hdl.handle.net/2115/71232 https://doi.org/10.1002/2017JC012941 eng eng American Geophysical Union http://hdl.handle.net/2115/71232 Journal of Geophysical Research Oceans, 123(2): 939-951 http://dx.doi.org/10.1002/2017JC012941 Copyright 2018 American Geophysical Union sea ice biogeochemical cycles Southern Ocean crack nutrient algae 660 article fthokunivhus https://doi.org/10.1002/2017JC012941 2023-08-18T00:06:05Z Cracks are common and natural features of sea ice formed in the polar oceans. In this study, a sea ice crack in flooded, multiyear, land-fast Antarctic sea ice was examined to assess its influence on biological productivity and the transport of nutrients and microalgae into the upper layers of neighboring sea ice. The water inside the crack and the surrounding host ice were characterized by a strong discoloration (brown color), an indicator of a massive algal bloom. Salinity and oxygen isotopic ratio measurements indicated that 64-84% of the crack water consisted of snow meltwater supplied during the melt season. Measurements of nutrient and chlorophyll a concentrations within the slush layer pool (the flooded layer at the snow-ice interface) revealed the intrusion of water from the crack, likely forced by mixing with underlying seawater during the tidal cycle. Our results suggest that sea ice crack formation provides conditions favorable for algal blooms by directly exposing the crack water to sunlight and supplying nutrients from the under-ice water. Subsequently, constituents of the crack water modified by biological activity were transported into the upper layer of the flooded sea ice. They were then preserved in the multiyear ice column formed by upward growth of sea ice caused by snow ice formation in areas of significant snow accumulation. Plain Language Summary Formation of cracks in sea ice affects the environment associated with biological production and biogeochemical cycling in the surface ocean of sea ice systems. Because cracks are likely to form frequently within the sea ice during the season of ice melting and ice breaking, the contributions of cracks to biological production and biogeochemical cycling may be significant in ice-covered oceans. In the future, the melting of sea ice in polar oceans will strongly affect the output of biogeochemical parameters trapped within sea ice and their use in primary and secondary production within surface oceans. In the case of multiyear, land-fast ice, ... Article in Journal/Newspaper Antarc* Antarctic Sea ice Southern Ocean Hokkaido University Collection of Scholarly and Academic Papers (HUSCAP) Antarctic Southern Ocean Journal of Geophysical Research: Oceans 123 2 939 951 |
institution |
Open Polar |
collection |
Hokkaido University Collection of Scholarly and Academic Papers (HUSCAP) |
op_collection_id |
fthokunivhus |
language |
English |
topic |
sea ice biogeochemical cycles Southern Ocean crack nutrient algae 660 |
spellingShingle |
sea ice biogeochemical cycles Southern Ocean crack nutrient algae 660 Nomura, Daiki Aoki, Shigeru Simizu, Daisuke Iida, Takahiro Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice |
topic_facet |
sea ice biogeochemical cycles Southern Ocean crack nutrient algae 660 |
description |
Cracks are common and natural features of sea ice formed in the polar oceans. In this study, a sea ice crack in flooded, multiyear, land-fast Antarctic sea ice was examined to assess its influence on biological productivity and the transport of nutrients and microalgae into the upper layers of neighboring sea ice. The water inside the crack and the surrounding host ice were characterized by a strong discoloration (brown color), an indicator of a massive algal bloom. Salinity and oxygen isotopic ratio measurements indicated that 64-84% of the crack water consisted of snow meltwater supplied during the melt season. Measurements of nutrient and chlorophyll a concentrations within the slush layer pool (the flooded layer at the snow-ice interface) revealed the intrusion of water from the crack, likely forced by mixing with underlying seawater during the tidal cycle. Our results suggest that sea ice crack formation provides conditions favorable for algal blooms by directly exposing the crack water to sunlight and supplying nutrients from the under-ice water. Subsequently, constituents of the crack water modified by biological activity were transported into the upper layer of the flooded sea ice. They were then preserved in the multiyear ice column formed by upward growth of sea ice caused by snow ice formation in areas of significant snow accumulation. Plain Language Summary Formation of cracks in sea ice affects the environment associated with biological production and biogeochemical cycling in the surface ocean of sea ice systems. Because cracks are likely to form frequently within the sea ice during the season of ice melting and ice breaking, the contributions of cracks to biological production and biogeochemical cycling may be significant in ice-covered oceans. In the future, the melting of sea ice in polar oceans will strongly affect the output of biogeochemical parameters trapped within sea ice and their use in primary and secondary production within surface oceans. In the case of multiyear, land-fast ice, ... |
format |
Article in Journal/Newspaper |
author |
Nomura, Daiki Aoki, Shigeru Simizu, Daisuke Iida, Takahiro |
author_facet |
Nomura, Daiki Aoki, Shigeru Simizu, Daisuke Iida, Takahiro |
author_sort |
Nomura, Daiki |
title |
Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice |
title_short |
Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice |
title_full |
Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice |
title_fullStr |
Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice |
title_full_unstemmed |
Influence of Sea Ice Crack Formation on the Spatial Distribution of Nutrients and Microalgae in Flooded Antarctic Multiyear Ice |
title_sort |
influence of sea ice crack formation on the spatial distribution of nutrients and microalgae in flooded antarctic multiyear ice |
publisher |
American Geophysical Union |
url |
http://hdl.handle.net/2115/71232 https://doi.org/10.1002/2017JC012941 |
geographic |
Antarctic Southern Ocean |
geographic_facet |
Antarctic Southern Ocean |
genre |
Antarc* Antarctic Sea ice Southern Ocean |
genre_facet |
Antarc* Antarctic Sea ice Southern Ocean |
op_relation |
http://hdl.handle.net/2115/71232 Journal of Geophysical Research Oceans, 123(2): 939-951 http://dx.doi.org/10.1002/2017JC012941 |
op_rights |
Copyright 2018 American Geophysical Union |
op_doi |
https://doi.org/10.1002/2017JC012941 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
123 |
container_issue |
2 |
container_start_page |
939 |
op_container_end_page |
951 |
_version_ |
1776204953071648768 |