Weakening Atlantic overturning circulation causes South Atlantic salinity pile-up

Zhu, Chenyu; Liu, Zhengyu

doi:10.1038/s41558-020-0897-7

Cited by 51 publications

(68 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(2020) showed that the pattern of warming and cooling described above emerges in coupled models as the spatial “fingerprint” of a weakening AMOC. The simulated AMOC weakening is consistent with a century‐scale reconstruction in the Florida Current region (Piecuch, 2020), remote salinity trends (Zhu & Liu, 2020), and shorter‐term circulation measurements at 26°N (Smeed et al., 2018), the latter of which have been linked directly to observed SST cooling south of Greenland via ocean heat transport calculations (Bryden et al., 2020).…”

Section: Introductionsupporting

confidence: 77%

“…In particular, while local forcing associated with internal atmospheric variability can superimpose short-term SST anomalies upon the long-term trend in this region (Chen et al, 2014(Chen et al, , 2015, studies like Caesar et al (2018) and Liu et al (2020) showed that the pattern of warming and cooling described above emerges in coupled models as the spatial "fingerprint" of a weakening AMOC. The simulated AMOC weakening is consistent with a century-scale reconstruction in the Florida Current region (Piecuch, 2020), remote salinity trends (Zhu & Liu, 2020), and shorter-term circulation measurements at 26°N (Smeed et al, 2018), the latter of which have been linked directly to observed SST cooling south of Greenland via ocean heat transport calculations (Bryden et al, 2020).…”

supporting

confidence: 80%

See 1 more Smart Citation

The Atmospheric Response to North Atlantic SST Trends, 1870–2019

Karnauskas

Zhang

Amaya

2021

Geophysical Research Letters

View full text Add to dashboard Cite

Many of the ways in which the atmospheric circulation has changed, and will change, in response to anthropogenic radiative forcing are a direct result of global energy imbalances. For example, the Hadley cells are expected to expand poleward due to perturbations in the global, zonal mean atmospheric energy budget (see Staten et al., 2020, and references therein). In the tropical Pacific, changes in the Walker circulation have been the subject of intense research, with a leading theory pointing to atmospheric thermodynamic constraints (e.g.

show abstract

Section: Introductionsupporting

confidence: 77%

supporting

confidence: 80%

The Atmospheric Response to North Atlantic SST Trends, 1870–2019

Karnauskas

Zhang

Amaya

2021

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…This signal is particularly visible in the redistributed heat content of the North Atlantic, which peaks in 2037 before declining rapidly, as well as the redistributed salinity content of the South Atlantic, which begins to increase at approximately the same time. This is consistent with previous studies (Zhu and Liu, 2020) which find a 'pile up' of salinity in the South Atlantic as a result of AMOC slowdown.…”

Section: Implementation: Estimating Redistributionsupporting

confidence: 93%

“…Curiously, we find that the penetration to depth of the excess redistributed salinity and density signals are far weaker than that of temperature, which, particularly in the Atlantic, accounts for the majority of deep warming. However, we do find several signals in surface excess and redistributed salinity changes consistent with hydrological amplification, as well as a salinity signal in the South Atlantic as a previously identified 'salinity pile up' in the South Atlantic consistent with AMOC slowdown (Zhu and Liu, 2020). By the 2090's, the Southern and Subtropical North Atlantic show increasing redistributed surface salinity as a result of AMOC slowdown, with a decreasing redistributed salinity in the Subpolar North Atlantic.…”

Section: Discussionsupporting

confidence: 73%

Decomposing oceanic temperature and salinity change using ocean carbon change

Turner

Brown

Oliver

et al. 2021

Preprint

View full text Add to dashboard Cite

Abstract. As the planet warms due to the accumulation of anthropogenic CO2 in the atmosphere, the global ocean uptake of heat can largely be described as a linear function of anthropogenic CO2 uptake. This relates the oceans mitigation of atmospheric warming and carbon sequestration, as well as its increasing heat content. Patterns of ocean salinity also change as the earth system warms due to hydrological cycle intensification and perturbations to air-sea freshwater fluxes. Local temperature and salinity change in the ocean may result from perturbed air-sea fluxes of heat and freshwater (excess temperature, salinity), or from variability resulting from reorganisation of the preindustrial temperature and salinity fields (redistributed temperature, salinity), which are largely due to circulation changes. Here, we present a novel method in which, by tracking the redistribution of preindustrial carbon, we may estimate the redistribution of temperature and salinity using only local spatial information. We demonstrate this technique by estimating the redistribution of heat and salinity in the NEMO OGCM coupled to the MEDUSA-2 Biogeochemistry model under a RCP8.5 scenario over 1860–2099. We find on the longest timescales, the patterns of excess heat and salinity storage are dominated by increases in excess heat and salinity in the Atlantic, and that excess salinity is generally negative in other basins, compensating for strong atmospheric transport of excess salinity to the Atlantic. We also find significant redistribution of heat away from the North Atlantic, and of salinity to the South Atlantic, consistent with AMOC slowdown. Temperature change at depth is accounted for predominately by redistributed, rather than excess heat, but the opposite is true for salinity, where the excess component accounts for the majority of changes at depth. Though by the end of the simulation excess heat is the largest contribution to density change and steric sea level rise, the storage of excess salinity greatly reduces variability in excess density, particularly in the Atlantic. Here, redistribution of the preindustrial heat and salinity fields also produce generally opposing changes in sea level, though patterns are less clear elsewhere. As expected, the regional strength of excess heat and salinity signal grows through the model run. In addition, the regional strength of the redistributed temperature and salinity signals also grow, indicating increasing circulation variability or systematic circulation change on at least the time scale of the model run.

show abstract

“…There is increasing evidence from paleoclimate proxies as well as modern sea level and salinity observations that the Atlantic Meridional Overturning Circulation (AMOC) has significantly weakened in past decades and is at its weakest in at least a millennium (Caesar et al, 2021;Piecuch, 2020;Zhu & Liu, 2020). Recent statistical analyses of sea-surface temperature and salinity observations give rise to the concern that this decline may be a sign for an ongoing loss of stability of the circulation, rather than just a temporal weakening (Boers, 2021).…”

Section: New Evidence Of Changementioning

confidence: 99%

Ten new insights in climate science 2021: a horizon scan

et al. 2021

View full text Add to dashboard Cite

Non-technical summaryWe summarize some of the past year's most important findings within climate change-related research. New research has improved our understanding about the remaining options to achieve the Paris Agreement goals, through overcoming political barriers to carbon pricing, taking into account non-CO 2 factors, a well-designed implementation of demand-side and nature-based solutions, resilience building of ecosystems and the recognition that climate change mitigation costs can be justified by benefits to the health of humans and nature alone. We consider new insights about what to expect if we fail to include a new dimension of fire extremes and the prospect of cascading climate tipping elements.

show abstract

Weakening Atlantic overturning circulation causes South Atlantic salinity pile-up

Cited by 51 publications

References 43 publications

The Atmospheric Response to North Atlantic SST Trends, 1870–2019

The Atmospheric Response to North Atlantic SST Trends, 1870–2019

Decomposing oceanic temperature and salinity change using ocean carbon change

Ten new insights in climate science 2021: a horizon scan

Contact Info

Product

Resources

About