气候变化领域集成服务门户(CCPortal): Effects of buoyancy and wind forcing on southern ocean climate change

CCPortal

DOI	10.1175/JCLI-D-19-0877.1
	Effects of buoyancy and wind forcing on southern ocean climate change
	SHI J.-R.; TALLEY L.D.; XIE S.-P.; LIU W.; GILLE S.T.
发表日期	2020
ISSN	0894-8755
起始页码	10003
结束页码	10020
卷号	33 期号:23
英文摘要	Observations show that since the 1950s, the Southern Ocean has stored a large amount of anthropogenic heat and has freshened at the surface. These patterns can be attributed to two components of surface forcing: Poleward-intensified westerly winds and increased buoyancy flux from freshwater and heat. Here we separate the effects of these two forcing components by using a novel partial-coupling technique. We show that buoyancy forcing dominates the overall response in the temperature and salinity structure of the Southern Ocean. Wind stress change results in changes in subsurface temperature and salinity that are closely related to intensified residual meridional overturning circulation. As an important result, we show that buoyancy and wind forcing result in opposing changes in salinity: The wind-induced surface salinity increase due to upwelling of saltier subsurface water offsets surface freshening due to amplification of the global hydrological cycle. Buoyancy and wind forcing further lead to different vertical structures of Antarctic Circumpolar Current (ACC) transport change; buoyancy forcing causes an ACC transport increase (3.161.6 Sv; 1 Sv[106m3 s21) by increasing the meridional density gradient across the ACC in the upper 2000 m, while the wind-induced response is more barotropic, with the whole column transport increased by 8.7 6 2.3 Sv. While previous research focused on the wind effect on ACC intensity, we show that surface horizontal current acceleration within the ACC is dominated by buoyancy forcing. These results shed light on how the Southern Ocean might change under global warming, contributing to more reliable future projections. © 2020 American Meteorological Society.
英文关键词	Global warming; Ocean currents; Wind effects; Antarctic circumpolar current; Coupling techniques; Horizontal currents; Hydrological cycles; Meridional overturning circulations; Subsurface temperature; Vertical structures; Wind-induced response; Buoyancy; buoyancy; buoyancy forcing; climate change; climate forcing; global warming; marine atmosphere; reliability analysis; salinity; temperature effect; wind forcing; Southern Ocean
语种	英语
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/170997
作者单位	Scripps Institution of Oceanography, University of California San Diego, San Diego, CA, United States; Department of Earth and Planetary Sciences, University of California Riverside, Riverside, CA, United States
推荐引用方式 GB/T 7714	SHI J.-R.,TALLEY L.D.,XIE S.-P.,et al. Effects of buoyancy and wind forcing on southern ocean climate change[J],2020,33(23).
APA	SHI J.-R.,TALLEY L.D.,XIE S.-P.,LIU W.,&GILLE S.T..(2020).Effects of buoyancy and wind forcing on southern ocean climate change.Journal of Climate,33(23).
MLA	SHI J.-R.,et al."Effects of buoyancy and wind forcing on southern ocean climate change".Journal of Climate 33.23(2020).