气候变化领域集成服务门户(CCPortal): New observations of the distribution, morphology and dissolution dynamics of cryogenic gypsum in the Arctic Ocean

CCPortal

DOI	10.5194/tc-14-1795-2020
	New observations of the distribution, morphology and dissolution dynamics of cryogenic gypsum in the Arctic Ocean
	Wollenburg J.E.; Iversen M.; Katlein C.; Krumpen T.; Nicolaus M.; Castellani G.; Peeken I.; Flores H.
发表日期	2020
ISSN	19940416
起始页码	1795
结束页码	1808
卷号	14 期号:6
英文摘要	To date, observations on a single location indicate that cryogenic gypsum (Ca[SO4]ĝ «2H2O) may constitute an efficient but hitherto overlooked ballasting mineral enhancing the efficiency of the biological carbon pump in the Arctic Ocean. In June-July 2017 we sampled cryogenic gypsum under pack ice in the Nansen Basin north of Svalbard using a plankton net mounted on a remotely operated vehicle (ROVnet). Cryogenic gypsum crystals were present at all sampled stations, which suggested a persisting cryogenic gypsum release from melting sea ice throughout the investigated area. This was supported by a sea ice backtracking model, indicating that gypsum release was not related to a specific region of sea ice formation. The observed cryogenic gypsum crystals exhibited a large variability in morphology and size, with the largest crystals exceeding a length of 1 cm. Preservation, temperature and pressure laboratory studies revealed that gypsum dissolution rates accelerated with increasing temperature and pressure, ranging from 6 % d-1 by mass in polar surface water (-0.5 ĝˆ C) to 81 % d-1 by mass in Atlantic Water (2.5 ĝˆ C at 65 bar). When testing the preservation of gypsum in formaldehyde-fixed samples, we observed immediate dissolution. Dissolution at warmer temperatures and through inappropriate preservation media may thus explain why cryogenic gypsum was not observed in scientific samples previously. Direct measurements of gypsum crystal sinking velocities ranged between 200 and 7000 m d-1, suggesting that gypsum-loaded marine aggregates could rapidly sink from the surface to abyssal depths, supporting the hypothesized potential of gypsum as a ballasting mineral in the Arctic Ocean. © 2020 Copernicus GmbH. All rights reserved.
英文关键词	biological pump; cryogenic fluid; crystal structure; dissolution; gypsum; melting; remotely operated vehicle; sea ice; spatial distribution; surface water; Arctic; Arctic Ocean; Atlantic Ocean; Eurasian Basin; Nansen Basin; Svalbard; Svalbard and Jan Mayen
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202250
作者单位	Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, 27570, Germany; MARUM - Zentrum für Marine Umweltwissenschaften der Universität Bremen, University of Bremen, Bremen, 27359, Germany
推荐引用方式 GB/T 7714	Wollenburg J.E.,Iversen M.,Katlein C.,et al. New observations of the distribution, morphology and dissolution dynamics of cryogenic gypsum in the Arctic Ocean[J],2020,14(6).
APA	Wollenburg J.E..,Iversen M..,Katlein C..,Krumpen T..,Nicolaus M..,...&Flores H..(2020).New observations of the distribution, morphology and dissolution dynamics of cryogenic gypsum in the Arctic Ocean.Cryosphere,14(6).
MLA	Wollenburg J.E.,et al."New observations of the distribution, morphology and dissolution dynamics of cryogenic gypsum in the Arctic Ocean".Cryosphere 14.6(2020).