Skip to main content Accessibility help

Rapid bottom-water circulation changes during the last glacial cycle in the coastal low-latitude NE Atlantic

  • David Gallego-Torres (a1) (a2), Oscar E. Romero (a1), Francisca Martínez-Ruiz (a1), Jung-Hyun Kim (a3), Barbara Donner (a4) and Miguel Ortega-Huertas (a2)...


Previous paleoceanographic studies along the NW African margin focused on the dynamics of surface and intermediate waters, whereas little attention has been devoted to deep-water masses. Currently, these deep waters consist mainly of North Atlantic Deep Waters as part of the Atlantic Meridional Overturning Circulation (AMOC). However, this configuration was altered during periods of AMOC collapse. We present a high-resolution reconstruction of bottom-water ventilation and current evolution off Mauritania from the last glacial maximum into the early Holocene. Applying redox proxies (Mo, U and Mn) measured on sediments from off Mauritania, we describe changes in deep-water oxygenation and we infer the evolution of deep-water conditions during millennial-scale climate/oceanographic events in the area. The second half of Heinrich Event 1 and the Younger Dryas were recognized as periods of reduced ventilation, coinciding with events of AMOC reduction. We propose that these weakening circulation events induced deficient deep-water oxygenation in the Mauritanian upwelling region, which together with increased productivity promoted reducing conditions and enhanced organic-matter preservation. This is the first time the effect of AMOC collapse in the area is described at high resolution, broadening the knowledge on basin-wide oceanographic changes associated with rapid climate variability during the last deglaciation.


Corresponding author

*Corrresponding author: Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR). Avenida de las Palmeras, 4. 18100 Armilla, Granada, Spain. E-mail address: (D. Gallego-Torres).


Hide All
Adkins, J.F., McIntyre, K., and Schrag, D.P. The salinity, temperature, and δ18O of the glacial deep ocean. Science 298, (2002). 17691773.
Algeo, T.J., and Tribovillard, N. Environmental analysis of paleoceanographic systems based on molybdenum–uranium covariation. Chemical Geology 268, (2009). 211225.
Arthur, M.A., Brumsack, H.-J., Jenkyns, H.C., and Schlanger, S.O. Stratigraphy, geochemistry, and paleoceanography of organic carbon-rich Cretaceous sequences. Ginsburg, R.N., and Beauoin, B. Cretaceous Resources, Events and Rhythms. (1990). Kluwer, Dordrecht. 75119.
Bard, E. Correction of accelerator mass spectrometry 14C ages measured in planktonic foraminifera: paleoceanographic implications. Paleoceanography 3, (1988). 635645.
Bloemsma, M.R. et al. Modelling the joint variability of grain size and chemical composition in sediments. Sedimentary Geology 280, (2012). 135148.
Brumsack, H.J. Geochemistry of Cretaceous black shales from the Atlantic Ocean (DSDP Legs 11, 14, 36 and 41). Chemical Geology 31, (1980). 125.
Calvert, S.E., and Pedersen, T.F. Geochemistry of recent oxic and anoxic marine sediments: implications for the geological record. Marine Geology 113, (1993). 6788.
Calvert, S.E., and Pedersen, T.F. Chapter fourteen elemental proxies for palaeoclimatic and palaeoceanographic variability in marine sediments: interpretation and application. Developments in Marine Geology (2007). 567644.
Chapman, M.R., and Shackleton, N.J. Millennial-scale fluctuations in North Atlantic heat flux during the last 150 000 years. Earth and Planetary Science Letters 159, (1998). 5770.
Dansgaard, W., Johnsen, S.J., Clausen, H.B., Dahl-Jensen, D., Gundestrup, N.S., Hammer, C.U., Hvidberg, C.S., Steffensen, J.P., Sveinbjörnsdottir, A.E., Jouzel, J., and Bond, G. Evidence for general instability of past climate from a 250-ka ice-core record. Nature 364, (1993). 218220.
de Lange, G.J. Distribution of exchangeable, fixed, organic and total nitrogen in interbedded turbiditic/pelagic sediments of the Madeira Abyssal Plain, eastern North Atlantic. Marine Geology 109, (1992). 95114.
de Lange, G.J. Oxic vs. anoxic diagenetic alteration of turbiditic sediments in the Madeira Abyssal Plain, eastern North Atlantic. Proceedings of the Ocean Drilling Program: Scientific Results 157, (1998). 573580.
de Lange, G.J., and Ten Haven, H.L. Recent sapropel formation in the Eastern Mediterranean. Nature 305, (1983). 797798.
de Lange, G.J., Thomson, J., Reitz, A., Slomp, C.P., Principato, M.S., Erba, E., and Corselli, C. Synchronous basin-wide formation and redox-controlled preservation of a Mediterranean sapropel. Nature Geoscience 1, (2008). 606610.
de Menocal, P., Ortiz, J., Guilderson, T., Adkins, J., Sarnthein, M., Baker, L., and Yarusinsky, M. Abrupt onset and termination of the African Humid Period: rapid climate responses to gradual insolation forcing. Quaternary Science Reviews 19, (2000). 347361.
de Menocal, P., Ortiz, J., Guilderson, T., and Sarnthein, M. Coherent high- and low-latitude climate variability during the Holocene warm period. Science 288, (2000). 21982202.
Eberwein, A., and Mackensen, A. Last Glacial Maximum paleoproductivity and water masses off NW-Africa: evidence from benthic foraminifera and stable isotopes. Marine Micropaleontology 67, (2008). 87103.
Filipsson, H.L., Romero, O.E., Jan-Berend, W.S., and Donner, B. Relationships between primary productivity and bottom-water oxygenation off northwest Africa during the last deglaciation. Journal of Quaternary Science 26, (2011). 448456.
Froelich, P.N., Klinkhammer, G.P., Bender, M.L., Luedtke, N.A., Heath, G.R., Cullen, D., Dauphin, P., Hammond, D., Hartman, B., and Maynard, V. Early oxidation of organic matter in pelagic sediments of the eastern equatorial Atlantic: suboxic diagenesis. Geochimica et Cosmochimica Acta 43, (1979). 10751090.
Gallego-Torres, D., Martinez-Ruiz, F., Paytan, A., Jimenez-Espejo, F.J., and Ortega-Huertas, M. Pliocene–Holocene evolution of depositional conditions in the eastern Mediterranean: role of anoxia vs. productivity at time of sapropel deposition. Palaeogeography, Palaeoclimatology, Palaeoecology 246, (2007). 424439.
Gallego-Torres, D., Martinez-Ruiz, F., De Lange, G., Jimenez-Espejo, F.J., and Ortega-Huertas, M. Trace-elemental derived paleoceanographic and paleoclimatic conditions for Pleistocene Eastern Mediterranean sapropels. Palaeogeography Palaeoclimatology Palaeoecology 293, (2010). 7689.
Gherardi, J.M., Labeyrie, L., McManus, J.F., Francois, R., Skinner, L.C., and Cortijo, E. Evidence from the Northeastern Atlantic basin for variability in the rate of the meridional overturning circulation through the last deglaciation. Earth and Planetary Science Letters 240, (2005). 710723.
Grootes, P.M., and Stuiver, M. Oxygen 18/16 variability in Greenland snow and ice with 10-3- to 105-year time resolution. Journal of Geophysical Research 102, (1997). 2645526470.
Hall, I.R., Evans, H.K., and Thornalley, D.J.R. Deep water flow speed and surface ocean changes in the subtropical North Atlantic during the last deglaciation. Global and Planetary Change 79, (2011). 255263.
Haslett, S.K., and Davies, C.F.C. Late Quaternary climate-ocean changes in western North Africa: offshore geochemical evidence. Transactions of the Institute of British Geographers 31, (2006). 3452.
Jones, B., and Manning, D.A.C. Comparison of geochemical indices used for the interpretation of palaeoredox conditions in ancient mudstones. Chemical Geology 111, (1994). 111129.
Kim, J.H., Meggers, H., Rimbu, N., Lohmann, G., Freudnethal, T., Müller, P.J., and Schneider, R.R. Impacts of the North Atlantic gyre circulation on Holocene climate off northwest Africa. Geology 35, (2007). 387390.
Kim, J.H., Romero, O.E., Lohmann, G., Donner, B., Laepple, T., Haam, E., and Sinninghe Damste, J.S. Pronounced subsurface cooling of North Atlantic waters off Northwest Africa during Dansgaard–Oeschger interstadials. Earth and Planetary Science Letters 339–340, (2012). 95102.
Kuhlmann, H., Meggers, H., Freudenthal, T., and Wefer, G. The transition of the monsoonal and the N Atlantic climate system off NW Africa during the Holocene. Geophysical Research Letters 31, (2004). 14.
Labeyrie, L., Waelbroeck, C., Cortijo, E., Michel, E., and Duplessy, J.C. Changes in deep water hydrology during the last deglaciation. Changements de l'hydrologie profonde pendant la dernière déglaciation 337, (2005). 919927.
Lippold, J., Mulitza, S., Mollenhauer, G., Weyer, S., Heslop, D., and Christl, M. Boundary scavenging at the East Atlantic margin does not negate use of 231 Pa/230Th to trace Atlantic overturning. Earth and Planetary Science Letters 333–334, (2012). 317331.
Lynch-Stieglitz, J., Adkins, J.F., Curry, W.B., Dokken, T., Hall, I.R., Herguera, J.C., Hirschi, J.J.M., Ivanova, E.V., Kissel, C., Marchal, O., Marchitto, T.M., McCave, I.N., McManus, J.F., Mulitza, S., Ninnemann, U., Peeters, F., Yu, E.F., and Zahn, R. Atlantic meridional overturning circulation during the last glacial maximum. Science 316, (2007). 6669.
Marchal, O., François, R., Stocker, T.F., and Joos, F. Ocean thermohaline circulation and sedimentary 231PA/230Th ratio. Paleoceanography 15, (2000). 625641.
Martinez, P., Bertrand, P., Shimmield, G.B., Cochrane, K., Jorissen, F.J., Foster, J., and Dignan, M. Upwelling intensity and ocean productivity changes off Cape Blanc (northwest Africa) during the last 70,000 years: geochemical and micropalaeontological evidence. Marine Geology 158, (1999). 5774.
Martrat, B. et al. Four climate cycles of recurring deep and surface water destabilizations on the Iberian margin. Science 317, 5837 (2007). 502507.
McManus, J.F., Francois, R., Gherardl, J.M., Kelgwin, L., and Drown-Leger, S. Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes. Nature 428, (2004). 834837.
McManus, J., Berelson, W.M., Klinkhammer, G.P., Hammond, D.E., and Holm, C. Authigenic uranium: relationship to oxygen penetration depth and organic carbon rain. Geochimica et Cosmochimica Acta 69, (2005). 95108.
Mittelstaedt, E. The ocean boundary along the northwest African coast: circulation and oceanographic properties at the sea surface. Progress in Oceanography 26, (1991). 307355.
Morford, J.L., Emerson, S.R., Breckel, E.J., and Kim, S.H. Diagenesis of oxyanions (V, U, Re, and Mo) in pore waters and sediments from a continental margin. Geochimica et Cosmochimica Acta 69, (2005). 50215032.
Morford, J.L., Martin, W.R., François, R., and Carney, C.M. A model for uranium, rhenium, and molybdenum diagenesis in marine sediments based on results from coastal locations. Geochimica et Cosmochimica Acta 73, (2009). 29382960.
Mulitza, S. et al. Sahel megadroughts triggered by glacial slowdowns of Atlantic meridional overturning. Paleoceanography 23, 4 (2008).
Piotrowski, A.M., Galy, A., Nicholl, J.A.L., Roberts, N., Wilson, D.J., Clegg, J.A., and Yu, J. Reconstructing deglacial North and South Atlantic deep water sourcing using foraminiferal Nd isotopes. Earth and Planetary Science Letters 357–358, (2012). 289297.
Piper, D.Z., and Calvert, S.E. A marine biogeochemical perspective on black shale deposition. Earth-Science Reviews 95, (2009). 6396.
Praetorius, S.K., McManus, J.F., Oppo, D.W., and Curry, W.B. Episodic reductions in bottom-water currents since the last ice age. Nature Geoscience 1, (2008). 449452.
Rahmstorf, S. Ocean circulation and climate during the past 120,000 years. Nature 419, (2002). 207214.
Roberts, N.L., Piotrowski, A.M., McManus, J.F., and Keigwin, L.D. Synchronous deglacial overturning and water mass source changes. Science 327, (2012). 7578.
Romero, O.E., Kim, J.H., and Donner, B. Submillennial-to-millennial variability of diatom production off Mauritania, NW Africa, during the last glacial cycle. Paleoceanography 23, (2008).
Rutberg, R.L., Hemming, S.R., and Goldstein, S.L. Reduced North Atlantic Deep Water flux to the glacial Southern Ocean inferred from neodymium isotope ratios. Nature 405, (2000). 935938.
Sarnthein, M., Tetzlaff, G., Koopmann, B., Wolter, K., and Pflaumann, U. Glacial and interglacial wind regimes over the eastern subtropical Atlantic and North-West Africa. Nature 293, (1981). 193196.
Schmidt, B.C., and Lynch-Stieglitz, J. Florida Straits deglacial temperature and salinity change: implications for tropical hydrologic cycle variability. Paleoceanography 26, (2011). PA4205
Skinner, L.C., and Shackleton, N.J. Deconstructing terminations I and II: revisiting the glacioeustatic paradigm based on deep-water temperature estimates. Quaternary Science Reviews 25, (2006). 33123321.
Staubwasser, M., Sirocko, F., Grootes, P.M., and Erlenkeuser, H. South Asian monsoon climate change and radiocarbon in the Arabian Sea during early and middle Holocene. Paleoceanography 17, (2002). 15-1
Stuiver, M., Reimer, P.J., Bard, E., Beck, J.W., Burr, G.S., Hughen, K.A., Kromer, B., McCormac, G., Van Der Plicht, J., and Spurk, M. INTCAL98 radiocarbon age calibration, 24,000-0 cal BP. Radiocarbon 40, (1998). 10411083.
Thomson, J., Higgs, N.C., Croudace, I.W., Colley, S., and Hydes, D.J. Redox zonation of elements at an oxic/postoxic boundary in deep-sea sediments. Geochemical and Comochimical Acta 57, (1993). 579595.
Thomson, J., Higgs, N.C., Wilson, T.R.S., Croudace, I.W., de Lange, G.J., and van Santvoort, P.J.M. Redistribution and geochemical behaviour of redox-sensitive elements around S1, the most recent eastern Mediterranean sapropel. Geochimica et Cosmochimica Acta 59, (1995). 34873501.
Thornalley, D.J.R., Elderfield, H., and McCave, I.N. Reconstructing North Atlantic deglacial surface hydrography and its link to the Atlantic overturning circulation. Global and Planetary Change 79, (2011). 163175.
Tjallingii, R. et al. Coherent high- and low-latitude control of the northwest African hydrological balance. Nature Geoscience 1, 10 (2008). 670675.
Tribovillard, N., Algeo, T.J., Lyons, T., and Riboulleau, A. Trace metals as paleoredox and paleoproductivity proxies: an update. Chemical Geology 232, (2006). 1232.
van Der Weijden, C.H. Pitfalls of normalization of marine geochemical data using a common divisor. Marine Geology 184, (2002). 167187.
van Santvoort, P.J.M., de Lange, G.J., Thomson, J., Cussen, H., Wilson, T.R.S., Krom, M.D., and Strohle, K. Active post-depositional oxidation of the most recent sapropel (S1) in sediments of the eastern Mediterranean Sea. Geochimica et Cosmochimica Acta 60, (1996). 40074024.
Zhao, M., Eglinton, G., Haslett, S.K., Jordan, R.W., Sarnthein, M., and Zhang, Z. Marine and terrestrial biomarker records for the last 35,000 years at ODP site 658C off NW Africa. Organic Geochemistry 31, (2000). 919930.


Related content

Powered by UNSILO

Rapid bottom-water circulation changes during the last glacial cycle in the coastal low-latitude NE Atlantic

  • David Gallego-Torres (a1) (a2), Oscar E. Romero (a1), Francisca Martínez-Ruiz (a1), Jung-Hyun Kim (a3), Barbara Donner (a4) and Miguel Ortega-Huertas (a2)...


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.