气候变化领域集成服务门户(CCPortal): Arctic Ocean stratification set by sea level and freshwater inputs since the last ice age

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DOI	10.1038/s41561-021-00789-y
	Arctic Ocean stratification set by sea level and freshwater inputs since the last ice age
	Farmer J.R.; Sigman D.M.; Granger J.; Underwood O.M.; Fripiat F.; Cronin T.M.; Martínez-García A.; Haug G.H.
发表日期	2021
ISSN	17520894
英文摘要	Salinity-driven density stratification of the upper Arctic Ocean isolates sea-ice cover and cold, nutrient-poor surface waters from underlying warmer, nutrient-rich waters. Recently, stratification has strengthened in the western Arctic but has weakened in the eastern Arctic; it is unknown if these trends will continue. Here we present foraminifera-bound nitrogen isotopes from Arctic Ocean sediments since 35,000 years ago to reconstruct past changes in nutrient sources and the degree of nutrient consumption in surface waters, the latter reflecting stratification. During the last ice age and early deglaciation, the Arctic was dominated by Atlantic-sourced nitrate and incomplete nitrate consumption, indicating weaker stratification. Starting at 11,000 years ago in the western Arctic, there is a clear isotopic signal of Pacific-sourced nitrate and complete nitrate consumption associated with the flooding of the Bering Strait. These changes reveal that the strong stratification of the western Arctic relies on low-salinity inflow through the Bering Strait. In the central Arctic, nitrate consumption was complete during the early Holocene, then declined after 5,000 years ago as summer insolation decreased. This sequence suggests that precipitation and riverine freshwater fluxes control the stratification of the central Arctic Ocean. Based on these findings, ongoing warming will cause strong stratification to expand into the central Arctic, slowing the nutrient supply to surface waters and thus limiting future phytoplankton productivity. © 2021, The Author(s).
语种	英语
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/206889
作者单位	Department of Geosciences, Princeton University, Princeton, NJ, United States; Max Planck Institute for Chemistry, Mainz, Germany; Department of Marine Sciences, University of Connecticut, Groton, CT, United States; Department of Geosciences, Environment and Society, Université Libre de Bruxelles, Brussels, Belgium; Florence Bascom Geoscience Center, US Geological Survey, Reston, VA, United States; Department of Earth Sciences, ETH Zürich, Zurich, Switzerland
推荐引用方式 GB/T 7714	Farmer J.R.,Sigman D.M.,Granger J.,et al. Arctic Ocean stratification set by sea level and freshwater inputs since the last ice age[J],2021.
APA	Farmer J.R..,Sigman D.M..,Granger J..,Underwood O.M..,Fripiat F..,...&Haug G.H..(2021).Arctic Ocean stratification set by sea level and freshwater inputs since the last ice age.Nature Geoscience.
MLA	Farmer J.R.,et al."Arctic Ocean stratification set by sea level and freshwater inputs since the last ice age".Nature Geoscience (2021).