Journal ArticleDOI
Deepwater source variations during the last climatic cycle and their impact on the global deepwater circulation
J.-C. Duplessy,N.J. Shackleton,Richard G. Fairbanks,Laurent Labeyrie,Delia W Oppo,Nejib Kallel +5 more
TLDR
In this paper, a detailed reconstruction of the geographic distribution of ∂13C in benthic foraminifera in the Atlantic Ocean during the last glacial maximum was presented.Abstract:
The degree of similarity of the ∂13C records of the planktonic foraminiferal species N. pachyderma and of the benthic foraminiferal genus Cibicides in the high-latitude basins of the world ocean is used as an indicator of the presence of deepwater sources during the last climatic cycle. Whereas continuous formation of deep water is recognized in the southern ocean, the Norwegian Sea stopped acting as a sink for surface water during isotope stage 4 and the remainder of the last glaciation. However, deep water formed in the north Atlantic south of the Norwegian Sea during the last climatic cycle as early as isotope substage 5d, and this area was also the only active northern source during stages 4–2. A detailed reconstruction of the geographic distribution of ∂13C in benthic foraminifera in the Atlantic Ocean during the last glacial maximum shows that the most important deepwater mass originated from the southern ocean, whereas the Glacial North Atlantic Deep Water cannot be traced south of 40°N. At shallower depth an oxygenated 13C rich Intermediate Water mass extended from 45°N to 15°S. In the Pacific Ocean a ventilation higher than the modern one was also found in open ocean in the depth range 700–2600 m and is best explained by stronger formation of Intermediate Water in high northern latitudes.read more
Citations
More filters
Journal ArticleDOI
Intermediate water links to Deep Western Boundary Current variability in the subtropical NW Atlantic during marine isotope stages 5 and 4
TL;DR: In this article, the Deep Western Boundary Current (DWBC) was reconstructed from Ocean Drilling Program Sites 1057 and 1059 (2584 m and 2985 m water depth, respectively) to reconstruct the behavior of the DWBC on the Blake Outer Ridge (BOR).
Journal ArticleDOI
Deepwater circulation on Blake Outer Ridge (western North Atlantic) during the Holocene, Younger Dryas, and Last Glacial Maximum
Helena Kay Evans,Ian Hall +1 more
TL;DR: In this paper, the position and relative intensity of the Western Boundary Undercurrent (WBUC) during the Holocene, the Last Glacial Maximum (LGM), and the Younger Dryas (YD) intervals were investigated along the Blake Outer Ridge in the western subtropical North Atlantic.
Journal ArticleDOI
Enhanced Atlantic Meridional Overturning Circulation supports the Last Glacial Inception
Abel Guihou,Abel Guihou,Sylvain Pichat,Aline Govin,Silvia Osorio Nave,Elisabeth Michel,Jean-Claude Duplessy,Philippe Telouk,Laurent Labeyrie +8 more
TL;DR: In this paper, the authors presented a reconstruction of the evolution of the vertical structure of the rate of the AMOC from the Last Interglaciation to the subsequent glaciation (128,000-60,000 years ago) based on sedimentary ((231)Pa/(230)Th) records.
Journal ArticleDOI
The Role of North Atlantic Deep Water Formation in an OGCM’s Ventilation and Thermohaline Circulation
TL;DR: In this article, two coarse-resolution model experiments are carried out on an OGCM to examine the effects of North Atlantic Deep Water (NADW) formation on the thermohaline circulation (THC) and ventilation timescales of the abyssal ocean.
Journal ArticleDOI
Simulated ocean circulation and sediment transport in the North Atlantic during the Last Glacial Maximum and today
Dan Seidov,Bernd J. Haupt +1 more
TL;DR: In this paper, a large-scale ocean general circulation model (OGCM) is used to simulate the North Atlantic Ocean at the last glacial maximum (LGM) and the output of the model is used in a sedimentation model and in a model to trace water parcel trajectories.
References
More filters
Journal ArticleDOI
Smoothing and Differentiation of Data by Simplified Least Squares Procedures.
Journal ArticleDOI
The distribution of 13C of ΣCO2 in the world oceans
TL;DR: In this article, the results from 2252 samples from 107 hydrographic stations are presented as north-south vertical (depth) sections with δ13C contoured at intervals of 0.5−0.0075·AOU.
Journal ArticleDOI
North Atlantic thermohaline circulation during the past 20,000 years linked to high-latitude surface temperature
Edward A. Boyle,Lloyd D Keigwin +1 more
TL;DR: In this paper, the authors show that during a surface cooling event 10,000 to 12,000 years ago, higher Cd/Ca and lower 13C/12C ratios are observed in benthic foraminifera shells from rapidly accumulating western North Atlantic sediments.
Journal ArticleDOI
Comparison of Atlantic and Pacific paleochemical records for the last 215,000 years : changes in deep ocean circulation and chemical inventories
Edward A. Boyle,Lloyd D Keigwin +1 more
TL;DR: In this article, detailed Cd/Ca and δ 13 C data have been obtained for benthic foraminifera from western North Atlantic and Equatorial Pacific sediment cores, which indicate that bottom waters overlying the Atlantic site have been nutrient depleted relative to those at the Pacific site over the last 215,000 years.
Related Papers (5)
North Atlantic thermohaline circulation during the past 20,000 years linked to high-latitude surface temperature
Edward A. Boyle,Lloyd D Keigwin +1 more