气候变化领域集成服务门户(CCPortal): Meltwater-Enhanced Nutrient Export From Greenland's Glacial Fjords: A Sensitivity Analysis

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DOI	10.1029/2020JC016185
	Meltwater-Enhanced Nutrient Export From Greenland's Glacial Fjords: A Sensitivity Analysis
	Oliver H.; Castelao R.M.; Wang C.; Yager P.L.
发表日期	2020
ISSN	21699275
卷号	125 期号:7
英文摘要	As mass loss from the Greenland Ice Sheet accelerates, this modeling study considers how meltwater inputs to the ocean can impact marine ecosystems using a simplified fjord scenario. At marine-terminating glaciers in Greenland fjords, meltwater can be delivered far below the sea surface, both as subglacial runoff (from atmosphere-driven surface melt) and as basal melt (from ocean heat). Such delivery can result in buoyancy-driven upwelling and the upward entrainment of nutrient-rich deep water, which can support phytoplankton growth in fjord surface waters. For this study, we use an idealized fjord-scale model to investigate which properties of glaciers and fjords govern the transport of buoyantly upwelled nutrients from fjords. We model the influence of fjord geometry, hydrology, wind, tides, and phytoplankton growth within the fjord on meltwater-driven nutrient export to the ocean. We use the Regional Ocean Modeling System (ROMS) coupled to a buoyant plume model and a biogeochemical model to simulate physical and biogeochemical processes within an idealized tidewater glacial fjord. Results show that meltwater-driven nutrient export increases with larger subglacial discharge rates and deeper grounding lines, features that are both likely to change with continued ice sheet melting. Nutrient export decreases with longer residence times, allowing greater biological drawdown. While the absence of a coastal current in the model setup prevents the downstream advection of exported nutrients, results suggest that shelf-forced flows could influence nutrient residence time within fjords. This simplified model highlights key uncertainties requiring further observation to understand ecological impacts of Greenland mass loss. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	biogeochemical cycling; fjord circulation; Greenland marine-terminating glaciers; nutrient export; primary productivity; subglacial discharge plumes
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186781
作者单位	Department of Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, MA, United States; Department of Marine Sciences, University of Georgia, Athens, GA, United States; Department of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
推荐引用方式 GB/T 7714	Oliver H.,Castelao R.M.,Wang C.,et al. Meltwater-Enhanced Nutrient Export From Greenland's Glacial Fjords: A Sensitivity Analysis[J],2020,125(7).
APA	Oliver H.,Castelao R.M.,Wang C.,&Yager P.L..(2020).Meltwater-Enhanced Nutrient Export From Greenland's Glacial Fjords: A Sensitivity Analysis.Journal of Geophysical Research: Oceans,125(7).
MLA	Oliver H.,et al."Meltwater-Enhanced Nutrient Export From Greenland's Glacial Fjords: A Sensitivity Analysis".Journal of Geophysical Research: Oceans 125.7(2020).