气候变化领域集成服务门户(CCPortal): Coastal alterations influence deep water renewal in Norwegian sill fjords

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DOI	10.1016/j.ecss.2023.108604
	Coastal alterations influence deep water renewal in Norwegian sill fjords
	Johnsen, Ingrid A.; Loeng, Harald; Myksvoll, Mari S.
发表日期	2024
ISSN	0272-7714
EISSN	1096-0015
起始页码	297
卷号	297
英文摘要	Recent observations have heightened concerns that the reduced density of coastal water is leading to a decrease in the frequency of basin water renewal in Norwegian sill fjords. There are indications that coastal water is becoming lighter due to climate change. The renewal of fjord basin water constitutes the primary source of oxygenation in these fjords, and many sill fjords naturally undergo stagnation periods lasting up to several years. In this paper, we have mapped alterations in coastal water using time series data from hydrographic measurements along the coastline, utilizing them as input for a simplified two-layer fjord model. We demonstrate that the temperature has risen, salinity has decreased, and consequently, the density of coastal water has declined since approximately 1990. At a depth of 10 m, the rise in temperature and the reduction in salinity made similar contributions to the decrease in density. However, at depths of 50 and 100 m, the increasing temperature emerged as the primary factor. The density exhibited a more substantial decrease in the upper layers compared to the lower layers. Consequently, not only was the water less dense, but the stability of the water column had also increased. The estimated temperature in the fjord basins increased after 1990 in 98 out of 101 evaluated fjords, with an average increase of 0.6 degrees C. The altered coastal stratification had an impact on the estimated work against the buoyant forces in the fjord basins. In 78 out of the 101 fjords, the work against buoyant forces by diapycnal mixing increased. In most of the fjord basins where the work against buoyant forces increased, the rise was insufficient to compensate for the decreasing density at the coast. Consequently, basin water renewal occurred less frequently in 65 out of the 101 fjord basins along the Norwegian coast
英文关键词	fjord; Basin; Exchange; Sustainability; Climate change; Stratification
语种	英语
WOS研究方向	Marine & Freshwater Biology ; Oceanography
WOS类目	Marine & Freshwater Biology ; Oceanography
WOS记录号	WOS:001158700300001
来源期刊	ESTUARINE COASTAL AND SHELF SCIENCE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/290163
作者单位	Institute of Marine Research - Norway
推荐引用方式 GB/T 7714	Johnsen, Ingrid A.,Loeng, Harald,Myksvoll, Mari S.. Coastal alterations influence deep water renewal in Norwegian sill fjords[J],2024,297.
APA	Johnsen, Ingrid A.,Loeng, Harald,&Myksvoll, Mari S..(2024).Coastal alterations influence deep water renewal in Norwegian sill fjords.ESTUARINE COASTAL AND SHELF SCIENCE,297.
MLA	Johnsen, Ingrid A.,et al."Coastal alterations influence deep water renewal in Norwegian sill fjords".ESTUARINE COASTAL AND SHELF SCIENCE 297(2024).