Articles | Volume 19, issue 4
https://doi.org/10.5194/cp-19-765-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-19-765-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Late Neogene nannofossil assemblages as tracers of ocean circulation and paleoproductivity over the NW Australian shelf
Boris-Theofanis Karatsolis
CORRESPONDING AUTHOR
Department of Earth Sciences, Uppsala University, Uppsala, 752 36,
Sweden
Jorijntje Henderiks
Department of Earth Sciences, Uppsala University, Uppsala, 752 36,
Sweden
Related authors
No articles found.
Luka Šupraha and Jorijntje Henderiks
Biogeosciences, 17, 2955–2969, https://doi.org/10.5194/bg-17-2955-2020, https://doi.org/10.5194/bg-17-2955-2020, 2020
Short summary
Short summary
The cell size, degree of calcification and growth rates of coccolithophores impact their role in the carbon cycle and may also influence their adaptation to environmental change. Combining insights from culture experiments and the fossil record, we show that the selection for smaller cells over the past 15 Myr has been a common adaptive trait among different lineages. However, heavily calcified species maintained a more stable biogeochemical output than the ancestral lineage of E. huxleyi.
Andrea C. Gerecht, Luka Šupraha, Gerald Langer, and Jorijntje Henderiks
Biogeosciences, 15, 833–845, https://doi.org/10.5194/bg-15-833-2018, https://doi.org/10.5194/bg-15-833-2018, 2018
Short summary
Short summary
Calcifying phytoplankton play an import role in long-term CO2 removal from the atmosphere. We therefore studied the ability of a representative species to continue sequestrating CO2 under future climate conditions. We show that CO2 sequestration is negatively affected by both an increase in temperature and the resulting decrease in nutrient availability. This will impact the biogeochemical cycle of carbon and may have a positive feedback on rising CO2 levels.
M. Bordiga, J. Henderiks, F. Tori, S. Monechi, R. Fenero, A. Legarda-Lisarri, and E. Thomas
Clim. Past, 11, 1249–1270, https://doi.org/10.5194/cp-11-1249-2015, https://doi.org/10.5194/cp-11-1249-2015, 2015
Short summary
Short summary
Deep-sea sediments at ODP Site 1263 (Walvis Ridge, South Atlantic) show that marine calcifying algae decreased in abundance and size at the Eocene-Oligocene boundary, when the Earth transitioned from a greenhouse to a more glaciated and cooler climate. This decreased the food supply for benthic foraminifer communities. The plankton rapidly responded to fast-changing conditions, such as seasonal nutrient availability, or to threshold-levels in pCO2, cooling and ocean circulation.
A. C. Gerecht, L. Šupraha, B. Edvardsen, I. Probert, and J. Henderiks
Biogeosciences, 11, 3531–3545, https://doi.org/10.5194/bg-11-3531-2014, https://doi.org/10.5194/bg-11-3531-2014, 2014
Related subject area
Subject: Ocean Dynamics | Archive: Marine Archives | Timescale: Cenozoic
Nonlinear increase in seawater 87Sr ∕ 86Sr in the Oligocene to early Miocene and implications for climate-sensitive weathering
Limited exchange between the deep Pacific and Atlantic oceans during the warm mid-Pliocene and Marine Isotope Stage M2 “glaciation”
Late Cenozoic sea-surface-temperature evolution of the South Atlantic Ocean
Buoyancy forcing: a key driver of northern North Atlantic sea surface temperature variability across multiple timescales
Lipid-biomarker-based sea surface temperature record offshore Tasmania over the last 23 million years
Plio-Pleistocene Perth Basin water temperatures and Leeuwin Current dynamics (Indian Ocean) derived from oxygen and clumped-isotope paleothermometry
Temperate Oligocene surface ocean conditions offshore of Cape Adare, Ross Sea, Antarctica
A revised mid-Pliocene composite section centered on the M2 glacial event for ODP Site 846
Lessons from a high-CO2 world: an ocean view from ∼ 3 million years ago
Late Pliocene Cordilleran Ice Sheet development with warm northeast Pacific sea surface temperatures
Understanding the mechanisms behind high glacial productivity in the southern Brazilian margin
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 3: Insights from Oligocene–Miocene TEX86-based sea surface temperature reconstructions
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 2: Insights from Oligocene–Miocene dinoflagellate cyst assemblages
Variations in Mediterranean–Atlantic exchange across the late Pliocene climate transition
Revisiting the Ceara Rise, equatorial Atlantic Ocean: isotope stratigraphy of ODP Leg 154 from 0 to 5 Ma
Constraints on ocean circulation at the Paleocene–Eocene Thermal Maximum from neodymium isotopes
Expansion and diversification of high-latitude radiolarian assemblages in the late Eocene linked to a cooling event in the southwest Pacific
Microfossil evidence for trophic changes during the Eocene–Oligocene transition in the South Atlantic (ODP Site 1263, Walvis Ridge)
A major change in North Atlantic deep water circulation 1.6 million years ago
Contribution of changes in opal productivity and nutrient distribution in the coastal upwelling systems to Late Pliocene/Early Pleistocene climate cooling
Productivity response of calcareous nannoplankton to Eocene Thermal Maximum 2 (ETM2)
Technical note: Late Pliocene age control and composite depths at ODP Site 982, revisited
Pliocene three-dimensional global ocean temperature reconstruction
Heather M. Stoll, Leopoldo D. Pena, Ivan Hernandez-Almeida, José Guitián, Thomas Tanner, and Heiko Pälike
Clim. Past, 20, 25–36, https://doi.org/10.5194/cp-20-25-2024, https://doi.org/10.5194/cp-20-25-2024, 2024
Short summary
Short summary
The Oligocene and early Miocene periods featured dynamic glacial cycles on Antarctica. In this paper, we use Sr isotopes in marine carbonate sediments to document a change in the location and intensity of continental weathering during short periods of very intense Antarctic glaciation. Potentially, the weathering intensity of old continental rocks on Antarctica was reduced during glaciation. We also show improved age models for correlation of Southern Ocean and North Atlantic sediments.
Anna Hauge Braaten, Kim A. Jakob, Sze Ling Ho, Oliver Friedrich, Eirik Vinje Galaasen, Stijn De Schepper, Paul A. Wilson, and Anna Nele Meckler
Clim. Past, 19, 2109–2125, https://doi.org/10.5194/cp-19-2109-2023, https://doi.org/10.5194/cp-19-2109-2023, 2023
Short summary
Short summary
In the context of understanding current global warming, the middle Pliocene (3.3–3.0 million years ago) is an important interval in Earth's history because atmospheric carbon dioxide concentrations were similar to levels today. We have reconstructed deep-sea temperatures at two different locations for this period, and find that a very different mode of ocean circulation or mixing existed, with important implications for how heat was transported in the deep ocean.
Frida S. Hoem, Adrián López-Quirós, Suzanna van de Lagemaat, Johan Etourneau, Marie-Alexandrine Sicre, Carlota Escutia, Henk Brinkhuis, Francien Peterse, Francesca Sangiorgi, and Peter K. Bijl
Clim. Past, 19, 1931–1949, https://doi.org/10.5194/cp-19-1931-2023, https://doi.org/10.5194/cp-19-1931-2023, 2023
Short summary
Short summary
We present two new sea surface temperature (SST) records in comparison with available SST records to reconstruct South Atlantic paleoceanographic evolution. Our results show a low SST gradient in the Eocene–early Oligocene due to the persistent gyral circulation. A higher SST gradient in the Middle–Late Miocene infers a stronger circumpolar current. The southern South Atlantic was the coldest region in the Southern Ocean and likely the main deep-water formation location in the Middle Miocene.
Bjørg Risebrobakken, Mari F. Jensen, Helene R. Langehaug, Tor Eldevik, Anne Britt Sandø, Camille Li, Andreas Born, Erin Louise McClymont, Ulrich Salzmann, and Stijn De Schepper
Clim. Past, 19, 1101–1123, https://doi.org/10.5194/cp-19-1101-2023, https://doi.org/10.5194/cp-19-1101-2023, 2023
Short summary
Short summary
In the observational period, spatially coherent sea surface temperatures characterize the northern North Atlantic at multidecadal timescales. We show that spatially non-coherent temperature patterns are seen both in further projections and a past warm climate period with a CO2 level comparable to the future low-emission scenario. Buoyancy forcing is shown to be important for northern North Atlantic temperature patterns.
Suning Hou, Foteini Lamprou, Frida S. Hoem, Mohammad Rizky Nanda Hadju, Francesca Sangiorgi, Francien Peterse, and Peter K. Bijl
Clim. Past, 19, 787–802, https://doi.org/10.5194/cp-19-787-2023, https://doi.org/10.5194/cp-19-787-2023, 2023
Short summary
Short summary
Neogene climate cooling is thought to be accompanied by increased Equator-to-pole temperature gradients, but mid-latitudes are poorly represented. We use biomarkers to reconstruct a 23 Myr continuous sea surface temperature record of the mid-latitude Southern Ocean. We note a profound mid-latitude cooling which narrowed the latitudinal temperature gradient with the northward expansion of subpolar conditions. We surmise that this reflects the strengthening of the ACC and the expansion of sea ice.
David De Vleeschouwer, Marion Peral, Marta Marchegiano, Angelina Füllberg, Niklas Meinicke, Heiko Pälike, Gerald Auer, Benjamin Petrick, Christophe Snoeck, Steven Goderis, and Philippe Claeys
Clim. Past, 18, 1231–1253, https://doi.org/10.5194/cp-18-1231-2022, https://doi.org/10.5194/cp-18-1231-2022, 2022
Short summary
Short summary
The Leeuwin Current transports warm water along the western coast of Australia: from the tropics to the Southern Hemisphere midlatitudes. Therewith, the current influences climate in two ways: first, as a moisture source for precipitation in southwestern Australia; second, as a vehicle for Equator-to-pole heat transport. In this study, we study sediment cores along the Leeuwin Current pathway to understand its ocean–climate interactions between 4 and 2 Ma.
Frida S. Hoem, Luis Valero, Dimitris Evangelinos, Carlota Escutia, Bella Duncan, Robert M. McKay, Henk Brinkhuis, Francesca Sangiorgi, and Peter K. Bijl
Clim. Past, 17, 1423–1442, https://doi.org/10.5194/cp-17-1423-2021, https://doi.org/10.5194/cp-17-1423-2021, 2021
Short summary
Short summary
We present new offshore palaeoceanographic reconstructions for the Oligocene (33.7–24.4 Ma) in the Ross Sea, Antarctica. Our study of dinoflagellate cysts and lipid biomarkers indicates warm-temperate sea surface conditions. We posit that warm surface-ocean conditions near the continental shelf during the Oligocene promoted increased precipitation and heat delivery towards Antarctica that led to dynamic terrestrial ice sheet volumes in the warmer climate state of the Oligocene.
Timothy D. Herbert, Rocio Caballero-Gill, and Joseph B. Novak
Clim. Past, 17, 1385–1394, https://doi.org/10.5194/cp-17-1385-2021, https://doi.org/10.5194/cp-17-1385-2021, 2021
Short summary
Short summary
The Pliocene represents a geologically warm period with polar ice restricted to the Antarctic. Nevertheless, variability and ice volume persisted in the Pliocene. This work revisits a classic site on which much of our understanding of Pliocene paleoclimate variability is based and corrects errors in data sets related to ice volume and ocean surface temperature. In particular, it generates an improved representation of an enigmatic glacial episode in Pliocene times (circa 3.3 Ma).
Erin L. McClymont, Heather L. Ford, Sze Ling Ho, Julia C. Tindall, Alan M. Haywood, Montserrat Alonso-Garcia, Ian Bailey, Melissa A. Berke, Kate Littler, Molly O. Patterson, Benjamin Petrick, Francien Peterse, A. Christina Ravelo, Bjørg Risebrobakken, Stijn De Schepper, George E. A. Swann, Kaustubh Thirumalai, Jessica E. Tierney, Carolien van der Weijst, Sarah White, Ayako Abe-Ouchi, Michiel L. J. Baatsen, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Ran Feng, Chuncheng Guo, Anna S. von der Heydt, Stephen Hunter, Xiangyi Li, Gerrit Lohmann, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Christian Stepanek, and Zhongshi Zhang
Clim. Past, 16, 1599–1615, https://doi.org/10.5194/cp-16-1599-2020, https://doi.org/10.5194/cp-16-1599-2020, 2020
Short summary
Short summary
We examine the sea-surface temperature response to an interval of climate ~ 3.2 million years ago, when CO2 concentrations were similar to today and the near future. Our geological data and climate models show that global mean sea-surface temperatures were 2.3 to 3.2 ºC warmer than pre-industrial climate, that the mid-latitudes and high latitudes warmed more than the tropics, and that the warming was particularly enhanced in the North Atlantic Ocean.
Maria Luisa Sánchez-Montes, Erin L. McClymont, Jeremy M. Lloyd, Juliane Müller, Ellen A. Cowan, and Coralie Zorzi
Clim. Past, 16, 299–313, https://doi.org/10.5194/cp-16-299-2020, https://doi.org/10.5194/cp-16-299-2020, 2020
Short summary
Short summary
In this paper, we present new climate reconstructions in SW Alaska from recovered marine sediments in the Gulf of Alaska. We find that glaciers reached the Gulf of Alaska during a cooling climate 2.9 million years ago, and after that the Cordilleran Ice Sheet continued growing during a global drop in atmospheric CO2 levels. Cordilleran Ice Sheet growth could have been supported by an increase in heat supply to the SW Alaska and warm ocean evaporation–mountain precipitation mechanisms.
Rodrigo da Costa Portilho-Ramos, Tainã Marcos Lima Pinho, Cristiano Mazur Chiessi, and Cátia Fernandes Barbosa
Clim. Past, 15, 943–955, https://doi.org/10.5194/cp-15-943-2019, https://doi.org/10.5194/cp-15-943-2019, 2019
Short summary
Short summary
Fossil microorganisms from the last glacial found in marine sediments collected off southern Brazil suggest that more productive austral summer upwelling and more frequent austral winter incursions of nutrient-rich waters from the Plata River boosted regional productivity year-round. While upwelling was more productive due to the higher silicon content from the Southern Ocean, more frequent riverine incursions were modulated by stronger alongshore southwesterly winds.
Julian D. Hartman, Francesca Sangiorgi, Ariadna Salabarnada, Francien Peterse, Alexander J. P. Houben, Stefan Schouten, Henk Brinkhuis, Carlota Escutia, and Peter K. Bijl
Clim. Past, 14, 1275–1297, https://doi.org/10.5194/cp-14-1275-2018, https://doi.org/10.5194/cp-14-1275-2018, 2018
Short summary
Short summary
We reconstructed sea surface temperatures for the Oligocene and Miocene periods (34–11 Ma) based on archaeal lipids from a site close to the Wilkes Land coast, Antarctica. Our record suggests generally warm to temperate surface waters: on average 17 °C. Based on the lithology, glacial and interglacial temperatures could be distinguished, showing an average 3 °C offset. The long-term temperature trend resembles the benthic δ18O stack, which may have implications for ice volume reconstructions.
Peter K. Bijl, Alexander J. P. Houben, Julian D. Hartman, Jörg Pross, Ariadna Salabarnada, Carlota Escutia, and Francesca Sangiorgi
Clim. Past, 14, 1015–1033, https://doi.org/10.5194/cp-14-1015-2018, https://doi.org/10.5194/cp-14-1015-2018, 2018
Short summary
Short summary
We document Southern Ocean surface ocean conditions and changes therein during the Oligocene and Miocene (34–10 Myr ago). We infer profound long-term and short-term changes in ice-proximal oceanographic conditions: sea surface temperature, nutrient conditions and sea ice. Our results point to warm-temperate, oligotrophic, ice-proximal oceanographic conditions. These distinct oceanographic conditions may explain the high amplitude in inferred Oligocene–Miocene Antarctic ice volume changes.
Ángela García-Gallardo, Patrick Grunert, and Werner E. Piller
Clim. Past, 14, 339–350, https://doi.org/10.5194/cp-14-339-2018, https://doi.org/10.5194/cp-14-339-2018, 2018
Short summary
Short summary
We study the variability in Mediterranean–Atlantic exchange, focusing on the surface Atlantic inflow across the mid-Pliocene warm period and the onset of the Northern Hemisphere glaciation, still unresolved by previous works. Oxygen isotope gradients between both sides of the Strait of Gibraltar reveal weak inflow during warm periods that turns stronger during severe glacials and the start of a negative feedback between exchange at the Strait and the Atlantic Meridional Overturning Circulation.
Roy H. Wilkens, Thomas Westerhold, Anna J. Drury, Mitchell Lyle, Thomas Gorgas, and Jun Tian
Clim. Past, 13, 779–793, https://doi.org/10.5194/cp-13-779-2017, https://doi.org/10.5194/cp-13-779-2017, 2017
Short summary
Short summary
Here we introduce the Code for Ocean Drilling Data (CODD), a unified and consistent system for integrating disparate data streams such as micropaleontology, physical properties, core images, geochemistry, and borehole logging. As a test case, data from Ocean Drilling Program Leg 154 (Ceara Rise – western equatorial Atlantic) were assembled into a new regional composite benthic stable isotope record covering the last 5 million years.
April N. Abbott, Brian A. Haley, Aradhna K. Tripati, and Martin Frank
Clim. Past, 12, 837–847, https://doi.org/10.5194/cp-12-837-2016, https://doi.org/10.5194/cp-12-837-2016, 2016
Short summary
Short summary
The Paleocene-Eocene Thermal Maximum (PETM) was a brief period when the Earth was in an extreme greenhouse state. We use neodymium isotopes to suggest that during this time deep-ocean circulation was distinct in each basin (North and South Atlanic, Southern, Pacific) with little exchange between. Moreover, the Pacific data show the most variability, suggesting this was a critical region possibly involved in both PETM triggering and remediation.
K. M. Pascher, C. J. Hollis, S. M. Bohaty, G. Cortese, R. M. McKay, H. Seebeck, N. Suzuki, and K. Chiba
Clim. Past, 11, 1599–1620, https://doi.org/10.5194/cp-11-1599-2015, https://doi.org/10.5194/cp-11-1599-2015, 2015
Short summary
Short summary
Radiolarian taxa with high-latitude affinities are present from at least the middle Eocene in the SW Pacific and become very abundant in the late Eocene at all investigated sites. A short incursion of low-latitude taxa is observed during the MECO and late Eocene warming event at Site 277. Radiolarian abundance, diversity and taxa with high-latitude affinities increase at Site 277 in two steps in the latest Eocene due to climatic cooling and expansion of cold water masses.
M. Bordiga, J. Henderiks, F. Tori, S. Monechi, R. Fenero, A. Legarda-Lisarri, and E. Thomas
Clim. Past, 11, 1249–1270, https://doi.org/10.5194/cp-11-1249-2015, https://doi.org/10.5194/cp-11-1249-2015, 2015
Short summary
Short summary
Deep-sea sediments at ODP Site 1263 (Walvis Ridge, South Atlantic) show that marine calcifying algae decreased in abundance and size at the Eocene-Oligocene boundary, when the Earth transitioned from a greenhouse to a more glaciated and cooler climate. This decreased the food supply for benthic foraminifer communities. The plankton rapidly responded to fast-changing conditions, such as seasonal nutrient availability, or to threshold-levels in pCO2, cooling and ocean circulation.
N. Khélifi and M. Frank
Clim. Past, 10, 1441–1451, https://doi.org/10.5194/cp-10-1441-2014, https://doi.org/10.5194/cp-10-1441-2014, 2014
J. Etourneau, C. Ehlert, M. Frank, P. Martinez, and R. Schneider
Clim. Past, 8, 1435–1445, https://doi.org/10.5194/cp-8-1435-2012, https://doi.org/10.5194/cp-8-1435-2012, 2012
M. Dedert, H. M. Stoll, D. Kroon, N. Shimizu, K. Kanamaru, and P. Ziveri
Clim. Past, 8, 977–993, https://doi.org/10.5194/cp-8-977-2012, https://doi.org/10.5194/cp-8-977-2012, 2012
N. Khélifi, M. Sarnthein, and B. D. A. Naafs
Clim. Past, 8, 79–87, https://doi.org/10.5194/cp-8-79-2012, https://doi.org/10.5194/cp-8-79-2012, 2012
H. J. Dowsett, M. M. Robinson, and K. M. Foley
Clim. Past, 5, 769–783, https://doi.org/10.5194/cp-5-769-2009, https://doi.org/10.5194/cp-5-769-2009, 2009
Cited articles
Anand, P., Elderfield, H., and Conte, M. H: Calibration of Mg/Ca thermometry
in planktonic foraminifera from a sediment trap time series, Paleoceanography, 18, 1050, https://doi.org/10.1029/2002PA000846, 2003.
Aubry, M.-P.: A major Pliocene coccolithophore turnover: Change in morphological strategy in the photic zone, Geol. Soc. Am., 424, 51,
https://doi.org/10.1130/SPE424, 2007.
Auer, G., De Vleeschouwer, D., Smith, R. A., Bogus, K., Groeneveld, J.,
Grunert, P., Castañeda, I. S., Petrick, B., Christensen, B., Fulthorpe,
C., Gallagher, S. J., and Henderiks, J.: Timing and Pacing of Indonesian
Throughflow Restriction and Its Connection to Late Pliocene Climate Shifts,
Paleoceanogr. Paleoclim., 34, 635–657, https://doi.org/10.1029/2018PA003512, 2019.
Auer, G., Petrick, B., Yoshimura, T., Mamo, B. L., Reuning, L., Takayanagi,
H., De Vleeschouwer, D., and Martinez-Garcia, A.: Intensified organic carbon
burial on the Australian shelf after the Middle Pleistocene transition,
Quaternary Sci. Rev., 262, 106965, https://doi.org/10.1016/j.quascirev.2021.106965, 2021.
Ballegeer, A. M., Flores, J. A., Sierro, F. J., and Andersen, N.: Monitoring
fluctuations of the Subtropical Front in the Tasman Sea between 3.45 and
2.45 Ma (ODP site 1172), Palaeogeogr. Palaeoclim. Palaeoecol., 313–314,
215–224, https://doi.org/10.1016/j.palaeo.2011.11.001, 2012.
Beaufort, L., Lancelot, Y., Camberlin, P., Cayre, O., Vincent, E., Bassinot,
F., and Labeyrie, L.: Insolation cycles as a major control of equatorial
Indian Ocean primary production, Science, 278, 1451–1454,
https://doi.org/10.1126/science.278.5342.1451, 1997.
Boeckel, B. and Baumann, K.-H.: Vertical and lateral variations in coccolithophore community structure across the subtropical frontal zone in
the South Atlantic Ocean, Mar. Micropaleontol., 67, 255–273,
https://doi.org/10.1016/j.marmicro.2008.01.014, 2008.
Bolton, C. T., Hernández-Sánchez, M. T., Fuertes, M. Á., González-Lemos, S., Abrevaya, L., Mendez-Vicente, A., Flores, J. A.,
Probert, I., Giosan, L., Johnson, J., and Stoll, H. M.: Decrease in
coccolithophore calcification and CO2 since the middle Miocene, Nat. Commun., 7, 10284, https://doi.org/10.1038/ncomms10284, 2016.
Bordiga, M., Bartol, M., and Henderiks, J.: Absolute nannofossil abundance
estimates: Quantifying the pros and cons of different techniques, Rev.
Micropaleontol., 58, 155–165, https://doi.org/10.1016/j.revmic.2015.05.002, 2015.
Bralower, T. J.: Evidence of surface water oligotrophy during the Paleocene-Eocene thermal maximum: Nannofossil assemblage data from Ocean
Drilling Program Site 690, Maud Rise, Weddell Sea, Paleoceanography, 17,
583–592, https://doi.org/10.1029/2001pa000662, 2002.
Chen, M., Pattiaratchi, C. B., Ghadouani, A., and Hanson, C.: Influence of
Storm Events on Chlorophyll Distribution Along the Oligotrophic Continental
Shelf Off South-Western Australia, Front. Mar. Sci., 7, 1–19,
https://doi.org/10.3389/fmars.2020.00287, 2020.
Christensen, B. A., Renema, W., Henderiks, J., De Vleeschouwer, D., Groeneveld, J., Castañeda, I. S., Reuning, L., Bogus, K., Auer, G.,
Ishiwa, T., McHugh, C. M., Gallagher, S. J., Fulthorpe, C. S., Mamo, B. L.,
Kominz, M. A., McGregor, H. V., Petrick, B. F., Takayanagi, H., Levin, E.,
Korpanty, C. A., Potts, D. C., Baranwal, S., Franco, D. R., Gurnis, M.,
Haller, C., He, Y., Himmler, T., Iwatani, H., Jatiningrum, R. S., Lee, E.
Y., Rastigar, A., and Zhang, W.: Indonesian Throughflow drove Australian
climate from humid Pliocene to arid Pleistocene, Geophys. Res. Lett., 44, 6914–6925, https://doi.org/10.1002/2017GL072977, 2017.
D'Adamo, N., Fandry, C., Buchan, S., and Domingues, C.: Northern sources of
the Leeuwin Current and the “Holloway Current” on the North West Shelf, J.
Roy. Soc. West. Aust., 92, 53–66, 2009.
Dekens, P. S., Lea, D. W., Pak, D. K., and Spero, H. J.: Core top calibration of Mg/Ca in tropical foraminifera: Refining paleotemperature estimation, Geochem. Geophy. Geosy., 3, 1–29, https://doi.org/10.1029/2001GC000200, 2002.
De Vleeschouwer, D., Petrick, B. F., and Martínez-García, A.: Stepwise Weakening of the Pliocene Leeuwin Current, Geophys. Res. Lett., 46, 8310–8319, https://doi.org/10.1029/2019GL083670, 2019.
De Vleeschouwer, D., Peral, M., Marchegiano, M., Füllberg, A., Meinicke,
N., Pälike, H., Auer, G., Petrick, B., Snoeck, C., Goderis, S., and
Claeys, P.: Plio-Pleistocene Perth Basin water temperatures and Leeuwin Current dynamics (Indian Ocean) derived from oxygen and clumped-isotope
paleothermometry, Clim. Past, 18, 1231–1253, https://doi.org/10.5194/cp-18-1231-2022, 2022.
Dickens, G. R. and Owen, R. M.: The Latest Miocene-Early Pliocene biogenic
bloom: A revised Indian Ocean perspective, Mar. Geol., 161, 75–91,
https://doi.org/10.1016/S0025-3227(99)00057-2, 1999.
Diester-Haass, L., Billups, K., and Emeis, K. C.: In search of the late
Miocene-early Pliocene “biogenic bloom” in the Atlantic Ocean (Ocean
Drilling Program Sites 982, 925 and 1088), Paleoceanography, 20, 1–13,
https://doi.org/10.1029/2005PA001139, 2005.
Du, Y. and Qu, T.: Three inflow pathways of the Indonesian throughflow as
seen from the simple ocean data assimilation, Dynam. Atmos. Ocean., 50, 233–256, https://doi.org/10.1016/j.dynatmoce.2010.04.001, 2010.
Eglinton, T. I., Conte, M. H., Eglinton, G., and Hayes, J. M.: Proceedings
of a workshop on alkenone-based paleoceanographic indicators, Geochem. Geophy. Geosy., 2, 1031, https://doi.org/10.1029/2000GC000122, 2001.
Farrell, J. W., Raffi, I., Janecek, T. C., Murray, D. W., Levitan, M., Dadey, K. A., Emeis, K.-C., Lyle, M., Flores, J.-A., and Hovan, S.: Late Neogene Sedimentation Patterns in the Eastern Equatorial Pacific, Proc. Ocean Drill. Program, 138 Sci. Results, https://doi.org/10.2973/odp.proc.sr.138.143.1995, 1995.
Fedorov, A. V., Dekens, P. S., McCarthy, M., Ravelo, A. C., DeMenocal, P. B., Barreiro, M., Pacanowski, R. C., and Philander, S. G.: The Pliocene paradox (mechanisms for a permanent El Niño), Science, 312, 1485–1489, https://doi.org/10.1126/science.1122666, 2006.
Fedorov, A. V., Brierley, C. M., and Emanuel, K.: Tropical cyclones and permanent El Niño in the early Pliocene epoch, Nature, 463, 1066–1070, https://doi.org/10.1038/nature08831, 2010.
Feng, M., Meyers, G., Pearce, A., and Wijffels, S.: Annual and interannual
variations of the Leeuwin Current at 32∘ S, J. Geophys. Res.-Oceans, 108, 3355, https://doi.org/10.1029/2002jc001763, 2003.
Feng, M., Waite, A. M., and Thompson, P. A.: Climate variability and ocean
production in the Leeuwin Current system off the west coast of Western
Australia, J. Roy. Soc. West. Aust., 92, 67–81, 2009.
Furnas, M.: Intra-seasonal and inter-annual variations in phytoplankton biomass, primary production and bacterial production at North West Cape,
Western Australia: Links to the 1997–1998 El Niño event, Cont. Shelf
Res., 27, 958–980, https://doi.org/10.1016/j.csr.2007.01.002, 2007.
Gallagher, S. J., Wallace, M. W., Li, C. L., Kinna, B., Bye, J. T., Akimoto,
K., and Torii, M.: Neogene history of the West Pacific Warm Pool, Kuroshio
and Leeuwin currents, Paleoceanography, 24, PA1206, https://doi.org/10.1029/2008PA001660, 2009.
Gallagher, S. J., Fulthorpe, C. S., Bogus, K., Auer, G., Baranwal, S.,
Castañeda, I. S., Christensen, B. A., De Vleeschouwer, D., Franco, D. R.,
Groeneveld, J., Gurnis, M., Haller, C., He, Y., Henderiks, J., Himmler, T.,
Ishiwa, T., Iwatani, H., Jatiningrum, R. S., Kominz, M. A., Korpanty, C. A.,
Lee, E. Y., Levin, E., Mamo, B. L., McGregor, H. V., McHugh, C. M., Petrick,
B. F., Potts, D. C., Rastegar Lari, A., Renema, W., Reuning, L., Takayanagi,
H., and Zhang, W.: Expedition 356 summary, in: Indonesian Throughflow, edited by: Gallagher, S. J., Fulthorpe, C. S., Bogus, K., and the Expedition 356 Scientists, Proceedings of the International Ocean Discovery Program 356, College Station, TX, https://doi.org/10.14379/iodp.proc.356.101.2017, 2017a.
Gallagher, S. J., Fulthorpe, C. S., Bogus, K., Auer, G., Baranwal, S.,
Castañeda, I. S., Christensen, B. A., De Vleeschouwer, D., Franco, D. R.,
Groeneveld, J., Gurnis, M., Haller, C., He, Y., Henderiks, J., Himmler, T.,
Ishiwa, T., Iwatani, H., Jatiningrum, R. S., Kominz, M. A., Korpanty, C. A.,
Lee, E. Y., Levin, E., Mamo, B. L., McGregor, H. V., McHugh, C. M., Petrick,
B. F., Potts, D. C., Rastegar Lari, A., Renema, W., Reuning, L., Takayanagi,
H., and Zhang, W.: Site U1463, in: Indonesian Throughflow, edited by: Gallagher, S. J., Fulthorpe, C. S., Bogus, K., and the Expedition 356 Scientists, Proceedings of the International Ocean Discovery Program 356, College Station, TX, https://doi.org/10.14379/iodp.proc.356.108.2017, 2017b.
Gallagher, S. J., Fulthorpe, C. S., Bogus, K., Auer, G., Baranwal, S.,
Castañeda, I. S., Christensen, B. A., De Vleeschouwer, D., Franco, D. R.,
Groeneveld, J., Gurnis, M., Haller, C., He, Y., Henderiks, J., Himmler, T.,
Ishiwa, T., Iwatani, H., Jatiningrum, R. S., Kominz, M. A., Korpanty, C. A.,
Lee, E. Y., Levin, E., Mamo, B. L., McGregor, H. V., McHugh, C. M., Petrick,
B. F., Potts, D. C., Rastegar Lari, A., Renema, W., Reuning, L., Takayanagi,
H., and Zhang, W.: Site U1464, in: Indonesian Throughflow, edited by: Gallagher, S. J., Fulthorpe, C. S., Bogus, K., and the Expedition 356 Scientists, Proceedings of the International Ocean Discovery Program 356, College Station, TX, https://doi.org/10.14379/iodp.proc.356.109.2017, 2017c.
Gibbs, S., Shackleton, N., and Young, J.: Orbitally forced climate signals in
mid-Pliocene nannofossil assemblages, Mar. Micropaleontol., 51, 39–56, https://doi.org/10.1016/j.marmicro.2003.09.002, 2004.
Gibbs, S. J., Young, J. R., Bralower, T. J., and Shackleton, N. J.: Nannofossil evolutionary events in the mid-Pliocene: An assessment of the
degree of synchrony in the extinctions of Reticulofenestra pseudoumbilicus and Sphenolithus abies, Palaeogeogr. Palaeoclim. Palaeoecol., 217, 155–172, https://doi.org/10.1016/j.palaeo.2004.11.005, 2005.
Gibbs, S. J., Stoll, H. M., Bown, P. R., and Bralower, T. J.: Ocean acidification and surface water carbonate production across the Paleocene-Eocene thermal maximum, Earth Planet. Sc. Lett., 295, 583–592, https://doi.org/10.1016/j.epsl.2010.04.044, 2010.
Godfrey, J. S.: The effect of the Indonesian throughflow on ocean circulation and heat exchange with the atmosphere: A review, J. Geophys. Res.-Oceans, 101, 12217–12237, https://doi.org/10.1029/95JC03860, 1996.
Godfrey, J. S. and Ridgway, K. R.: The Large-Scale Environment of the Poleward-Flowing Leeuwin Current, Western Australia: Longshore Steric Height
Gradients, Wind Stresses and Geostrophic Flow, J. Phys. Oceanogr., 15, 481–495, https://doi.org/10.1175/1520-0485(1985)015<0481:TLSEOT>2.0.CO;2, 1985.
Godfrey, J. S., Vaudrey, D. J., and Hahn, S. D.: Observations of the Shelf-Edge Current South of Australia, Winter 1982, J. Phys. Oceanogr., 16, 668–679, https://doi.org/10.1175/1520-0485(1986)016<0668:OOTSEC>2.0.CO;2, 1986.
Gordon, A. L., Ma, S., Olson, D. B., Hacker, P., Ffield, A., Talley, L. D.,
Wilson, D., and Baringer, M.: Advection and diffusion of Indonesian throughflow water within the Indian Ocean South Equatorial Current, Geophys.
Res. Lett., 24, 2573–2576, https://doi.org/10.1029/97GL01061, 1997.
Gradstein, F. M., Ogg, J. G., Schmitz, M. D., and Ogg, G. M. (Eds.): The
Geologic Time Scale 2012, in: Vol. 2, Elsevier, Amsterdam, p. 1144, ISBN 9780444594488, 2012.
Groeneveld, J., De Vleeschouwer, D., McCaffrey, J. C., and Gallagher, S. J.:
Dating the Northwest Shelf of Australia since the Pliocene, Geochem. Geophy. Geosy., 22, 1–20, https://doi.org/10.1029/2020GC009418, 2021.
Hammer, Ø., Harper, D. A. T., and Ryan, P. D.: PAST: Paleontological
Statistics Software Package for education and data analysis, Palaeontol. Electron., 4, 1–9, 2001.
Hannisdal, B., Henderiks, J., and Liow, L. H.: Long-term evolutionary and
ecological responses of calcifying phytoplankton to changes in atmospheric
CO2, Global Change Biol., 18(12), 3504–3516, https://doi.org/10.1111/gcb.12007, 2012.
Haq, B. U.: Biogeographic history of Miocene calcareous nannoplankton and
paleoceanography of the Atlantic Ocean, Micropaleontology, 26, 414–443,
https://doi.org/10.2307/1485353, 1980.
Haq, B. U. and Lohmann, G. P.: Early Cenozoic calcareous nannoplankton
biogeography of the Atlantic Ocean, Mar. Micropaleontol., 1, 119–194,
https://doi.org/10.1016/0377-8398(76)90008-6, 1976.
Harlay, J., Borges, A. V., Van Der Zee, C., Delille, B., Godoi, R. H. M.,
Schiettecatte, L. S., Roevros, N., Aerts, K., Lapernat, P. E., Rebreanu, L.,
Groom, S., Daro, M. H., Van Grieken, R., and Chou, L.: Biogeochemical study
of a coccolithophore bloom in the northern Bay of Biscay (NE Atlantic Ocean)
in June 2004, Prog. Oceanogr., 86, 317–336, https://doi.org/10.1016/j.pocean.2010.04.029, 2010.
Harris, G., Nilsson, C., Clementson, L., and Thomas, D.: The water masses of
the east coast of Tasmania: Seasonal and interannual variability and the
influence on phytoplankton biomass and productivity, Aust. J. Mar. Freshw.
Res., 38, 569–590, https://doi.org/10.1071/MF9870569, 1987.
He, Y., Wang, H., and Liu, Z.: Development of the Leeuwin Current on the
northwest shelf of Australia through the Pliocene-Pleistocene period, Earth
Planet. Sc. Lett., 559, 116767, https://doi.org/10.1016/j.epsl.2021.116767, 2021.
Henderiks, J., Bartol, M., Pige, N., Karatsolis, B. T.m and Lougheed, B. C.:
Shifts in Phytoplankton Composition and Stepwise Climate Change During the
Middle Miocene, Paleoceanogr. Paleoclim., 35, e2020PA003915, https://doi.org/10.1029/2020PA003915, 2020.
Hermoyian, C. S. and Owen, R. M.: Late Miocene-early Pliocene biogenic
bloom: Evidence from low-productivity regions of the Indian and Atlantic
oceans, Paleoceanography, 16, 95–100, https://doi.org/10.1029/2000PA000501, 2001.
Hirst, G. and Godfrey, J. S.: The Role of Indonesian Throughflow in a Global
Ocean GCM, J. Phys. Oceanogr., 23, 1057–1086,
https://doi.org/10.1175/1520-0485(1993)023<1057:TROITI>2.0.CO;2, 1993.
Holloway, P. E. and Nye, H.: Leeuwin current and wind distributions on the
southern part of the Australian North West Shelf between January 1982 and
July 1983, Mar. Freshw. Res., 36, 123–137, https://doi.org/10.1071/MF9850123, 1985.
Imai, R., Farida, M., Sato, T., and Iryu, Y.: Evidence for eutrophication in
the northwestern Pacific and eastern Indian oceans during the Miocene to
Pleistocene based on the nannofossil accumulation rate, Discoaster abundance, and coccolith size distribution of Reticulofenestra, Mar. Micropaleontol., 116, 15–27, https://doi.org/10.1016/j.marmicro.2015.01.001, 2015.
Imai, R., Sato, T., Chiyonobu, S., and Iryu, Y.: Reconstruction of Miocene to
Pleistocene sea-surface conditions in the eastern Indian Ocean on the basis
of calcareous nannofossil assemblages from ODP Hole 757B, Isl. Arct., 29,
e12373, https://doi.org/10.1111/iar.12373, 2020.
Karas, C., Nürnberg, D., Gupta, A. K., Tiedemann, R., Mohan, K., and
Bickert, T.: Mid-Pliocene climate change amplified by a switch in Indonesian
subsurface throughflow, Nat. Geosci., 2, 434–438, https://doi.org/10.1038/ngeo520,
2009.
Karas, C., Nürnberg, D., Tiedemann, R., and Garbe-Schönberg, D.:
Pliocene Indonesian Throughflow and Leeuwin Current dynamics: Implications
for Indian Ocean polar heat flux, Paleoceanography, 26, 1–9,
https://doi.org/10.1029/2010PA001949, 2011.
Karatsolis, B.-T. and Henderiks, J.: Late Miocene to Pliocene calcareous nannofossil assemblage records and paleotemperature gradients from the NW Australian shelf (IODP Sites U1463, U1464), Zenodo [data set],
https://doi.org/10.5281/zenodo.6965870, 2022.
Karatsolis, B.-T., De Vleeschouwer, D., Groeneveld, J., Christensen, B., and
Henderiks, J.: The Late Miocene to Early Pliocene “Humid Interval” on the
NW Australian Shelf: Disentangling climate forcing from regional basin
evolution, Paleoceanogr. Paleoclim., 35, e2019PA003780, https://doi.org/10.1029/2019PA003780, 2020.
Karatsolis, B.-T., Lougheed, B. C., De Vleeschouwer, D., and Henderiks, J.:
Abrupt conclusion of the late Miocene-early Pliocene biogenic bloom at
4.6–4.4 Ma, Nat. Commun., 13, 1–9, https://doi.org/10.1038/s41467-021-27784-6, 2022.
Kendrick, G. A., Goldberg, N. A., Harvey, E. S., and McDonald, J.: Historical
and contemporary influence of the Leeuwin Current on the marine biota of the
southwestern Australian continental shelf and the Recherche Archipelago, J.
Roy. Soc. West. Aust., 92, 211–219, 2009.
Kim, J.-H., Villanueva, L., Zell, C., and Sinninghe Damsté, J. S.: Biological source and provenance of deep-water derived isoprenoid tetraether
lipids along the Portuguese continental margin, Geochim. Cosmochim. Ac., 172, 177–204, https://doi.org/10.1016/j.gca.2015.09.010, 2016.
Kimura, S., Nakata, H., and Okazaki, Y.: Biological production in meso-scale
eddies caused by frontal disturbances of the Kuroshio Extension, ICES J.
Mar. Sci., 57, 133–142, https://doi.org/10.1006/jmsc.1999.0564, 2000.
Koch, C. and Young, J. R.: A simple weighing and dilution technique for determining absolute abundances of coccoliths from sediment samples, J.
Nannoplankt. Res., 29, 67–69, 2007.
Koslow, J. A., Pesant, S., Feng, M., Pearce, A., Fearns, P., Moore, T., Matear, R., and Waite, A.: The effect of the Leeuwin Current on phytoplankton
biomass and production off Southwestern Australia, J. Geophys. Res.-Oceans,
113, C07050, https://doi.org/10.1029/2007JC004102, 2008.
Longhurst, A.: A major seasonal phytoplankton bloom in the Madagascar Basin,
Deep.-Sea Res. Pt. I, 48, 2413–2422, https://doi.org/10.1016/S0967-0637(01)00024-3, 2001.
Marino, M. and Flores, J. A.: Miocene to Pliocene calcareous nannofossil
biostratigraphy at ODP Leg 177 Sites 1088 and 1090, Mar. Micropaleontol., 45, 291–307, https://doi.org/10.1016/S0377-8398(02)00033-6, 2002.
Müller, P., J., Kirst, G., Ruhland, G., von Storch, I., and Rosell-Melé, A.: Calibration of the alkenone paleotemperature index
based on core-tops from the eastern South Atlantic and the global ocean (60∘ N–60∘ S), Geochim. Cosmochim. Ac., 62, 1757–1772, https://doi.org/10.1016/S0016-7037(98)00097-0, 1998.
O'Dea, S. A., Gibbs, S. J., Bown, P. R., Young, J. R., Poulton, A. J., Newsam, C., and Wilson, P. A.: Coccolithophore calcification response to past
ocean acidification and climate change, Nat. Commun., 5, 1–7,
https://doi.org/10.1038/ncomms6363, 2014.
Okada, H. and Wells, P.: Late quaternary nannofossil indicators of climate
change in two deep-sea cores associated with the Leeuwin Current off Western
Australia, Palaeogeogr. Palaeoclim. Palaeoecol., 131, 413–432,
https://doi.org/10.1016/S0031-0182(97)00014-X, 1997.
Poulton, A. J., Stinchcombe, M. C., Achterberg, E. P., Bakker, D. C. E.,
Dumousseaud, C., Lawson, H. E., Lee, G. A., Richier, S., Suggett, D. J., and
Young, J. R.: Coccolithophores on the north-west European shelf: Calcification rates and environmental controls, Biogeosciences, 11, 3919–3940, https://doi.org/10.5194/bg-11-3919-2014, 2014.
Ridgway, K. R. and Condie, S. A.: The 5500-km-long boundary flow off western
and southern Australia, J. Geophys. Res.-Oceans, 109, 1–18,
https://doi.org/10.1029/2003JC001921, 2004.
Ridgway, K. R. and Godfrey, J. S.: The source of the Leeuwin Current seasonality, J. Geophys. Res.-Oceans, 120, 6843–6864, https://doi.org/10.1002/2015JC011049, 2015.
Shannon, C. E.: A Mathematical Theory of Communication, Bell Syst. Tech. J.,
27, 379–423, https://doi.org/10.1002/j.1538-7305.1948.tb01338.x, 1948.
Sharples, J., Moore, C. M., Hickman, A. E., Holligan, P. M., Tweddle, J. F.,
Palmer, M. R., and Simpson, J. H.: Internal tidal mixing as a control on
continental margin ecosystems, Geophys. Res. Lett., 36, 1–5,
https://doi.org/10.1029/2009GL040683, 2009.
Smith, M., De Deckker, P., Rogers, J., Brocks, J., Hope, J., Schmidt, S.,
Lopes dos Santos, R., and Schouten, S.: Comparison of , TEX86H and LDI temperature proxies for reconstruction of south-east Australian ocean temperatures, Org. Geochem., 64, 94–104,
https://doi.org/10.1016/j.orggeochem.2013.08.015, 2013.
Stuut, J.-B. W., De Deckker, P., Saavedra-Pellitero, M., Bassinot, F., Drury, A. J., Walczak, M. H., Nagashima, K., and Murayama, M.: A 5.3-million-year history of monsoonal precipitation in northwestern Australia, Geophys. Res. Lett., 46, 6946–6954, https://doi.org/10.1029/2019GL083035, 2020.
Suchéras-Marx, B., Escarguel, G., Ferreira, J., and Hammer, Ø.:
Statistical confidence intervals for relative abundances and abundance-based
ratios: Simple practical solutions for an old overlooked question, Mar.
Micropaleontol., 151, 101751, https://doi.org/10.1016/j.marmicro.2019.101751, 2019.
Takahashi, K. and Okada, H.: The paleoceanography for the last 30,000 years
in the Southeastern Indian Ocean by means of calcareous nannofossils, Mar.
Micropaleontol., 40, 83–103, https://doi.org/10.1016/S0377-8398(00)00033-5, 2000.
Thierstein, H. R. and Young, J. R. (Eds.): Coccolithophores: From Molecular
Processes to Global Impact, Springer, Berlin, Heidelberg, 565 pp., https://doi.org/10.1007/978-3-662-06278-4, 2004.
Thompson, P. A., Pesant, S., and Waite, A. M.: Contrasting the vertical
differences in the phytoplankton biology of a dipole pair of eddies in the
south-eastern Indian Ocean, Deep-Sea Res. Pt. II, 54, 1003–1028, https://doi.org/10.1016/j.dsr2.2006.12.009, 2007.
Thompson, P. A., Wild-Allen, K., Lourey, M., Rousseaux, C., Waite, A. M.,
Feng, M., and Beckley, L. E.: Nutrients in an oligotrophic boundary current:
Evidence of a new role for the Leeuwin Current, Prog. Oceanogr., 91, 345–359, https://doi.org/10.1016/j.pocean.2011.02.011, 2011.
van der Weijst, C. M. H., van der Laan, K. J., Peterse, F., Reichart, G.-J.,
Sangiorgi, F., Schouten, S., Veenstra, T. J. T., and Sluijs, A.: A
15-million-year surface- and subsurface-integrated TEX86 temperature
record from the eastern equatorial Atlantic, Clim. Past, 18, 1947–1962,
https://doi.org/10.5194/cp-18-1947-2022, 2022.
Van Oostende, N., Harlay, J., Vanelslander, B., Chou, L., Vyverman, W., and
Sabbe, K.: Phytoplankton community dynamics during late spring coccolithophore blooms at the continental margin of the Celtic Sea (North
East Atlantic, 2006–2008), Prog. Oceanogr., 104, 1–16, https://doi.org/10.1016/j.pocean.2012.04.016, 2012.
Wade, B. S. and Bown, P. R.: Calcareous nannofossils in extreme environments: The Messinian Salinity Crisis, Polemi Basin, Cyprus, Palaeogeogr. Palaeoclim. Palaeoecol., 233, 271–286, https://doi.org/10.1016/j.palaeo.2005.10.007, 2006.
Wara, M. W., Ravelo, A. C., and Delaney, M. L.: Climate change: Permanent El Niño-like conditions during the Pliocene warm period, Science, 309, 758–761, https://doi.org/10.1126/science.1112596, 2005.
Young, J.: Size variation of Neogene Reticulofenestra coccoliths from Indian Ocean DSDP Cores, J. Micropalaeontol., 9, 71–85, https://doi.org/10.1144/jm.9.1.71, 1990.
Short summary
Ocean circulation around NW Australia plays a key role in regulating the climate in the area and is characterised by seasonal variations in the activity of a major boundary current named the Leeuwin Current. By investigating nannofossils found in sediment cores recovered from the NW Australian shelf, we reconstructed ocean circulation in the warmer-than-present world from 6 to 3.5 Ma, as mirrored by long-term changes in stratification and nutrient availability.
Ocean circulation around NW Australia plays a key role in regulating the climate in the area and...