Ice-core evidence of late-Holocene reduction in North Atlantic Ocean heat transport

1999 ◽  
pp. 301-312 ◽  
Author(s):  
R. B. Alley ◽  
A. M. Ágústsdóttir ◽  
P. J. Fawcett
Keyword(s):  
Atlantic Ocean ◽  
Heat Transport ◽  
North Atlantic ◽  
Late Holocene ◽  
North Atlantic Ocean ◽  
Ice Core ◽  
Ocean Heat Transport

scholarly journals Impact of model resolution on Arctic sea ice and North Atlantic Ocean heat transport

2019 ◽  
Vol 53 (7-8) ◽  
pp. 4989-5017 ◽  
Author(s):  
David Docquier ◽  
Jeremy P. Grist ◽  
Malcolm J. Roberts ◽  
Christopher D. Roberts ◽  
Tido Semmler ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Sea Ice ◽  
Heat Transport ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Arctic Sea Ice ◽  
Model Resolution ◽  
Ocean Heat Transport ◽  
Arctic Sea

Micropaleontological Evidence for Increased Meridional Heat Transport in the North Atlantic Ocean During the Pliocene

Science ◽  
1992 ◽  
Vol 258 (5085) ◽  
pp. 1133-1135 ◽  
Author(s):  
H. J. Dowsett ◽  
T. M. Cronin ◽  
R. Z. Poore ◽  
R. S. Thompson ◽  
R. C. Whatley ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Heat Transport ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Meridional Heat Transport ◽  
The North ◽  
The North Atlantic

scholarly journals The Rapid Warming of the North Atlantic Ocean in the Mid-1990s in an Eddy-Permitting Ocean Reanalysis (1982–2013)

2016 ◽  
Vol 29 (15) ◽  
pp. 5417-5430 ◽  
Author(s):  
Chunxue Yang ◽  
Simona Masina ◽  
Alessio Bellucci ◽  
Andrea Storto
Keyword(s):  
Atlantic Ocean ◽  
Heat Transport ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Ocean Reanalysis ◽  
The North ◽  
Mean Temperature ◽  
The Mean ◽  
The North Atlantic ◽  
Mean State

Abstract The rapid warming in the mid-1990s in the North Atlantic Ocean is investigated by means of an eddy-permitting ocean reanalysis. Both the mean state and variability, including the mid-1990s warming event, are well captured by the reanalysis. An ocean heat budget applied to the subpolar gyre (SPG) region (50°–66°N, 60°–10°W) shows that the 1995–99 rapid warming is primarily dictated by changes in the heat transport convergence term while the surface heat fluxes appear to play a minor role. The mean negative temperature increment suggests a warm bias in the model and data assimilation corrects the mean state of the model, but it is not crucial to reconstruct the time variability of the upper-ocean temperature. The decomposition of the heat transport across the southern edge of the SPG into time-mean and time-varying components shows that the SPG warming is mainly associated with both the anomalous advection of mean temperature and the mean advection of temperature anomalies across the 50°N zonal section. The relative contributions of the Atlantic meridional overturning circulation (AMOC) and gyre circulation to the heat transport are also analyzed. It is shown that both the overturning and gyre components are relevant to the mid-1990s warming. In particular, the fast adjustment of the barotropic circulation response to the NAO drives the anomalous transport of mean temperature at the subtropical/subpolar boundary, while the slowly evolving AMOC feeds the large-scale advection of thermal anomalies across 50°N. The persistently positive phase of the NAO during the years prior to the rapid warming likely favored the cross-gyre heat transfer and the following SPG warming.

scholarly journals Reduction in Ocean Heat Transport at 26°N since 2008 Cools the Eastern Subpolar Gyre of the North Atlantic Ocean

2020 ◽  
Vol 33 (5) ◽  
pp. 1677-1689 ◽  
Author(s):  
Harry L. Bryden ◽  
William E. Johns ◽  
Brian A. King ◽  
Gerard McCarthy ◽  
Elaine L. McDonagh ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Heat Transport ◽  
North Atlantic ◽  
Ocean Heat Transport ◽  
North Atlantic Current ◽  
The North ◽  
Heat Uptake ◽  
The North Atlantic ◽  
Atlantic Current

AbstractNorthward ocean heat transport at 26°N in the Atlantic Ocean has been measured since 2004. The ocean heat transport is large—approximately 1.25 PW, and on interannual time scales it exhibits surprisingly large temporal variability. There has been a long-term reduction in ocean heat transport of 0.17 PW from 1.32 PW before 2009 to 1.15 PW after 2009 (2009–16) on an annual average basis associated with a 2.5-Sv (1 Sv ≡ 106 m3 s−1) drop in the Atlantic meridional overturning circulation (AMOC). The reduction in the AMOC has cooled and freshened the upper ocean north of 26°N over an area following the offshore edge of the Gulf Stream/North Atlantic Current from the Bahamas to Iceland. Cooling peaks south of Iceland where surface temperatures are as much as 2°C cooler in 2016 than they were in 2008. Heat uptake by the atmosphere appears to have been affected particularly along the path of the North Atlantic Current. For the reduction in ocean heat transport, changes in ocean heat content account for about one-quarter of the long-term reduction in ocean heat transport while reduced heat uptake by the atmosphere appears to account for the remainder of the change in ocean heat transport.

scholarly journals Mid-Pliocene Atlantic Meridional Overturning Circulation simulated in PlioMIP2

2020 ◽  
Author(s):  
Zhongshi Zhang ◽  
Xiangyu Li ◽  
Chuncheng Guo ◽  
Odd Helge Otterå ◽  
Kerim H. Nisancioglu ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Heat Transport ◽  
North Atlantic ◽  
Atlantic Meridional Overturning Circulation ◽  
Meridional Overturning Circulation ◽  
Ocean Heat Transport ◽  
Surface Warming ◽  
The North ◽  
Meridional Overturning ◽  
The North Atlantic

Abstract. In the Pliocene Model Intercomparison Project phase 2 (PlioMIP2), coupled climate models have been used to simulate an interglacial climate during the mid-Piacenzian warm period (mPWP, 3.264 to 3.025 Ma). Here, we compare the Atlantic Meridional Overturning Circulation (AMOC), poleward ocean heat transport and sea surface warming in the Atlantic simulated with these models. In PlioMIP2, all models simulate an intensified mid-Pliocene AMOC. However, there is no consistent response in the simulated Atlantic ocean heat transport, or the depth of the Atlantic overturning cell. The models show a large spread in the simulated AMOC maximum, the Atlantic ocean heat transport, as well as the surface warming in the North Atlantic. Although a few models simulate a surface warming of ~ 8–12 ° in the North Atlantic, similar to the reconstruction from Pliocene Research, Interpretation and Synoptic Mapping (PRISM), most models underestimate this warming. The large model-spread and model-data discrepancies in the PlioMIP2 ensemble does not support the hypothesis that an intensification of the AMOC, together with an increase in northward ocean heat transport, is the dominant forcing for the mid-Pliocene warm climate.

Coherency of late Holocene European speleothem δ18O records linked to North Atlantic Ocean circulation

2016 ◽  
Vol 49 (1-2) ◽  
pp. 595-618 ◽  
Author(s):  
Michael Deininger ◽  
Frank McDermott ◽  
Manfred Mudelsee ◽  
Martin Werner ◽  
Norbert Frank ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Ocean Circulation ◽  
North Atlantic ◽  
Late Holocene ◽  
North Atlantic Ocean

scholarly journals A new method to assess mesoscale contributions to meridional heat transport in the North Atlantic Ocean

2020 ◽  
Author(s):  
Andrew Delman ◽  
Tong Lee
Keyword(s):  
Atlantic Ocean ◽  
Heat Transport ◽  
North Atlantic ◽  
Large Scale ◽  
North Atlantic Ocean ◽  
Meridional Heat Transport ◽  
The North ◽  
Basin Scale ◽  
Wide Range ◽  
The North Atlantic

Abstract. The meridional heat transport (MHT) in the North Atlantic is critically important to climate variability and the global overturning circulation. A wide range of ocean processes contribute to North Atlantic MHT, ranging from basin-scale overturning and gyre motions to mesoscale instabilities (such as eddies). However, previous analyses of eddy MHT in the region have mostly focused on the contributions of time-variable velocity and temperature, rather than considering the spatial scales that are more fundamental to the physics of ocean eddies. In this study, a zonal spatial-scale decomposition separates large-scale from mesoscale velocity and temperature contributions to MHT, in order to characterize the physical processes driving MHT. Using this approach, we found that the mesoscale contributions to the time mean and interannual/decadal (ID) variability of MHT in the North Atlantic Ocean are larger than large-scale horizontal contributions, though smaller than the overturning contributions. Considering the 40° N transect as a case study, large-scale ID variability is mostly generated in the deeper part of the thermocline, while mesoscale ID variability has shallower origins. At this latitude, most ID MHT variability associated with mesoscales originates in two regions: a western boundary region (70°–60° W) associated with 1–4 year interannual variations, and an interior region (50°–35° W) associated with decadal variations. Surface eddy kinetic energy is not a reliable indicator of high MHT episodes, but the large-scale meridional temperature gradient is an important factor, by influencing the local temperature variance as well as the local correlation of velocity and temperature. Most of the mesoscale contribution to MHT at 40° N is associated with transient and propagating processes, but stationary mesoscale dynamics contribute substantially to MHT south of the Gulf Stream separation, highlighting the differences between the temporal and spatial decomposition of meridional temperature fluxes.

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