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Astronomical tuning of sediment sequences requires both unambiguous cycle-pattern recognition in climate proxy records and astronomical solutions, and independent information about the phase relationship between these two. Here we present two different astronomically tuned age models for the Oligocene-Miocene Transition (OMT) from Integrated Ocean Drilling Program Site U1334 (equatorial Pacific Ocean) to assess the effect tuning has on astronomically calibrated ages and the geologic time scale. These alternative age models (from ~22 to ~24 Ma) are based on different tunings between proxy records and eccentricity: the first age model is based on an aligning CaCO3 weight (wt%) to Earth's orbital eccentricity, the second age model is based on a direct age calibration of benthic foraminiferal stable carbon isotope ratios (d13C) to eccentricity. To independently test which tuned age model and associated tuning assumptions is in best agreement with independent ages based on tectonic plate-pair spreading rates, we assign our tuned ages to the magnetostratigraphic reversals identified in deep-marine magnetic anomaly profiles. Subsequently, we compute tectonic plate-pair spreading rates based on the tuned ages. The resultant, alternative spreading rate histories indicate that the CaCO3 tuned age model is most consistent with a conservative assumption of constant, or linearly changing, spreading rates. The CaCO3 tuned age model thus provides robust ages and durations for polarity chrons C6Bn.1n-C6Cn.1r, which are not based on astronomical tuning in the latest iteration of the Geologic Time Scale. Furthermore, it provides independent evidence that the relatively large (several 10,000 years) time lags documented in the benthic foraminiferal isotope records relative to orbital eccentricity, constitute a real feature of the Oligocene-Miocene climate system and carbon cycle. The age constraints from Site U1334 thus provide independent evidence that the delayed responses of the Oligocene-Miocene climate-cryosphere system and carbon cycle resulted from highly nonlinear feedbacks to astronomical forcing. Supplement to: Beddow, Helen M; Liebrand, Diederik; Wilson, Douglas S; Hilgen, Frederik J; Sluijs, Appy; Wade, Bridget S; Lourens, Lucas Joost (2018): Astronomical tunings of the Oligocene-Miocene transition from Pacific Ocean Site U1334 and implications for the carbon cycle. Climate of the Past, 14(3), 255-270

Pelagic sediments from the subtropical South Atlantic Ocean contain geographically extensive Oligocene ooze and chalk layers that consist almost entirely of the calcareous nannofossil Braarudosphaera. Poor recovery and the lack of precise dating of these horizons in previous studies has limited our understanding of the exact number of acmes, their timing and durations, and the causes of their recurrence. Here we present a high-resolution, astronomically tuned stratigraphy of Braarudosphaera oozes (29.5-27.9 Ma) from Ocean Drilling Program Site 1264 in the subtropical southeastern Atlantic Ocean. We identify seven acme events in the Braarudosphaera abundance record. The longest lasting acme event corresponds to a strong minimum in the ~2.4-My eccentricity cycle, and four acme events coincide with ~110-ky and 405-ky eccentricity maxima. We propose that eccentricity-modulated precession forcing of the freshwater budget of the South Atlantic Ocean resulted in the episodic formation of a shallow pycnocline and hyperstratification of the upper water column. We speculate that stratified surface water conditions may have served as a virtual sea floor, which facilitated the widespread Braarudosphaera acmes. This explanation reconciles the contrasting distribution patterns of Braarudosphaera in the modern ocean, limited largely to shallow water coastal settings, compared to their relatively brief and expanded oceanic distribution in the past. Supplement to: Liebrand, Diederik; Raffi, Isabella; Fraguas, Ángela; Laxenaire, Rémi; Bosmans, Joyce H C; Hilgen, Frederik J; Wilson, Paul A; Batenburg, Sietske J; Beddow, Helen M; Bohaty, Steven M; Bown, Paul R; Crocker, Anya J; Huck, Claire E; Lourens, Lucas Joost; Sabia, Luciana (2018): Orbitally Forced Hyperstratification of the Oligocene South Atlantic Ocean. Paleoceanography and Paleoclimatology, 33(5), 511-529

We use the fully coupled atmosphere-ocean three-dimensional model of intermediate complexity iLOVECLIM to simulate the climate and oxygen stable isotopic signal during the Last Glacial Maximum (LGM, 21 000 yr). By using a model that is able to explicitly simulate the sensor (d18O), results can be directly compared with data from climatic archives in the different realms.Our results indicate that iLOVECLIM reproduces well the main feature of the LGM climate in the atmospheric and oceanic components. The annual mean d18O in precipitation shows more depleted values in the northern and southern high latitudes during the LGM. The model reproduces very well the spatial gradient observed in ice core records over the Greenland ice-sheet. We observe a general pattern toward more enriched values for continental calcite d18O in the model at the LGM, in agreement with speleothem data. This can be explained by both a general atmospheric cooling in the tropical and subtropical regions and a reduction in precipitation as confirmed by reconstruction derived from pollens and plant macrofossils.Data-model comparison for sea surface temperature indicates that iLOVECLIM is capable to satisfyingly simulate the change in oceanic surface conditions between the LGM and present. Our data-model comparison for calcite d18O allows investigating the large discrepancies with respect to glacial temperatures recorded by different microfossil proxies in the North Atlantic region. The results argue for a trong mean annual cooling between the LGM and present (>6°C), supporting the foraminifera transfer function reconstruction but in disagreement with alkenones and dinocyst reconstructions. The data-model comparison also reveals that large positive calcite d18O anomaly in the Southern Ocean may be explained by an important cooling, although the driver of this pattern is unclear. We deduce a large positive d18Osw anomaly for the north Indian Ocean that contrasts with a large negative d18Osw anomaly in the China Sea between the LGM and present. This pattern may be linked to changes in the hydrological cycle over these regions. Our simulation of the deep ocean suggests that changes in d18Osw between the LGM and present are not spatially homogenous. This is supported by reconstructions derived from pore fluids in deep-sea sediments. The model underestimates the deep ocean cooling thus biasing the comparison with benthic calcite d18O data. Nonetheless, our data-model comparison support a heterogeneous cooling of few degrees (2-4°C) in the LGM Ocean. The supplement contains two excel files in zip-archive with compiled planktic and benthic foraminifera calcite d18O measurements of deep-sea cores for which both Last Glacial Maximum and Late Holocene d18O exist. The data are from various publications as given in the reference-column. Using individual datasets requires the citation of the original paper. Supplement to: Caley, Thibaut; Roche, D M; Waelbroeck, Claire; Michel, Elisabeth (2014): Oxygen stable isotopes during the Last Glacial Maximum climate: perspectives from data–model (iLOVECLIM) comparison. Climate of the Past, 10(6), 1939-1955

Antarctic ice sheet and Southern Ocean paleoceanographic configurations during the late Oligocene are not well resolved. They are however important to understand the influence of high-latitude Southern Hemisphere feedbacks on global climate under CO2 scenarios (between 400 and 750 ppm) projected by the IPCC for this century, assuming unabated CO2 emissions. Sediments recovered by the Integrated Ocean Drilling Program (IODP) at Site U1356, offshore of the Wilkes Land margin in East Antarctica, provide an opportunity to study ice sheet and paleoceanographic configurations during the late Oligocene (26-25 Ma). Our study, based on a combination of sediment facies analysis, magnetic susceptibility, density, and X-Ray Fluorescence geochemical data, shows that glacial and interglacial sediments are continuously reworked by bottom-currents, with maximum velocities occurring during the interglacial periods. Glacial sediments record poorly ventilated, low-oxygenation bottom water conditions, interpreted to result from a northward shift of westerly winds and surface oceanic fronts. Interglacial sediments record more oxygenated and ventilated bottom water conditions and strong current velocities, which suggests enhanced mixing of the water masses as a result of a southward shift of the Polar Front. Intervals with preserved carbonated nannofossils within some of the interglacial facies are interpreted to form under warmer paleoclimatic conditions when less corrosive warmer northern component water (e.g. North Atlantic sourced deep water) had a greater influence on the Site. Spectral analysis on the late Oligocene sediment interval show that the glacial-interglacial cyclicity and related displacements of the Southern Ocean frontal systems between 26-25 Ma were forced mainly by obliquity. The paucity of iceberg rafted debris (IRD) throughout the studied interval contrasts with earlier Oligocene and post-Miocene Climate Optimum sections from Site U1356 and with late Oligocene strata from the Ross Sea, which contain IRD and evidence for coastal glaciers and sea ice. These observations, supported by elevated sea surface paleotemperatures, the absence of sea-ice, and reconstructions of fossil pollen between 26 and 25 Ma at Site U1356, suggest that open ocean water conditions prevailed. Combined, these evidences suggest that glaciers or ice caps likely occupied the topographic highs and lowlands of the now marine Wilkes Subglacial Basin (WSB). Unlike today, the continental shelf was not over-deepened and thus ice sheets in the WSB were likely land-based and marine-based ice sheet expansion was likely limited to coastal regions. Supplement to: Salabarnada, Ariadna; Escutia, Carlota; Röhl, Ursula; Nelson, C Hans; McKay, Robert M; Jiménez-Espejo, Francisco Jose; Bijl, Peter K; Hartman, Julian D; Strother, Stephanie L; Salzmann, Ulrich; Evangelinos, Dimitris; López-Quirós, Adrián; Flores, José Abel; Sangiorgi, Francesca; Ikehara, Minoru; Brinkhuis, Henk (2018): Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 1: Insights from late Oligocene astronomically paced contourite sedimentation. Climate of the Past, 14(7), 991-1014

To quantitatively reconstruct the kinematic evolution of Central and Eastern Anatolia within the framework of Neotethyan subduction accommodating Africa-Eurasia convergence, we paleomagnetically assess timing and amount of vertical axis rotations across the Ulukisla and Sivas regions. We show paleomagnetic results from ~30 localities identifying a coherent rotation of a block - comprising the southern Kirsehir Block, the Ulukisla basin, the Central and Eastern Taurides, and the southern part of the Sivas basin. This block experienced a ~30° counter-clockwise vertical axis rotation since Oligocene time. Sediments in the northern Sivas region show clockwise rotations. We use the rotation patterns together with known fault zones to argue that the counter-clockwise rotating domain of south-central Turkey was bounded by the Savcili Thrust Zone and Deliler-Tecer Fault Zone in the north and by the African-Arabian trench in the south, the western boundary of which is poorly constrained and requires future study. Our new paleomagnetic constraints provide a key ingredient for future kinematic restorations of the Anatolian tectonic collage. We combine our extensive new dataset with existing data (Guerer et al., 2018, and references therein) to identify the dimension of rotating domains in Central and Eastern Anatolia, and identify structures that may have accommodated these rotations. Paleomagnetic interpretations and statistical analyses were carried out using the platform independent portal Paleomagnetism.org (Koymans et al., 2016). Supplement to: Gürer, Derya; van Hinsbergen, Douwe J J; Özkaptan, Murat; Creton, Iverna; Koymans, Mathijs R; Cascella, Antonio; Langereis, Cornelis G (2018): Paleomagnetic constraints on the timing and distribution of Cenozoic rotations in Central and Eastern Anatolia. Solid Earth, 9(2), 295-322

Supplement to: Bijl, Peter K; Houben, Alexander J P; Hartman, Julian D; Pross, Jörg; Salabarnada, Ariadna; Escutia, Carlota; Sangiorgi, Francesca (2018): Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 2: Insights from Oligocene–Miocene dinoflagellate cyst assemblages. Climate of the Past, 14(7), 1015-1033 Palynological counts from IODP Leg 318 Hole U1356A, Cores 95R-11R, and the lithological facies as observed in Salabarnada et al., CP 2018. Reworked dinocysts (as by Bijl et al., JM 2018), in situ dioncysts, acritarchs and terrestrial palynomorphs, as well as dinocyst ecogroups.

A brief (~150 kyr) period of widespread global average surface warming marks the transition between the Paleocene and Eocene epochs, ~56 million years ago. This so-called "Paleocene-Eocene thermal maximum" (PETM) is associated with the massive injection of 13C-depleted carbon, reflected in a negative carbon isotope excursion (CIE). Biotic responses include a global abundance peak (acme) of the subtropical dinoflagellate Apectodinium. Here we identify the PETM in a marine sedimentary sequence deposited on the East Tasman Plateau at Ocean Drilling Program (ODP) Site 1172 and show, based on the organic paleothermometer TEX86, that southwest Pacific sea surface temperatures increased from ~26 °C to ~33°C during the PETM. Such temperatures before, during and after the PETM are >10 °C warmer than predicted by paleoclimate model simulations for this latitude. In part, this discrepancy may be explained by potential seasonal biases in the TEX86 proxy in polar oceans. Additionally, the data suggest that not only Arctic, but also Antarctic temperatures may be underestimated in simulations of ancient greenhouse climates by current generation fully coupled climate models. An early influx of abundant Apectodinium confirms that environmental change preceded the CIE on a global scale. Organic dinoflagellate cyst assemblages suggest a local decrease in the amount of river run off reaching the core site during the PETM, possibly in concert with eustatic rise. Moreover, the assemblages suggest changes in seasonality of the regional hydrological system and storm activity. Finally, significant variation in dinoflagellate cyst assemblages during the PETM indicates that southwest Pacific climates varied significantly over time scales of 103 - 104 years during this event, a finding comparable to similar studies of PETM successions from the New Jersey Shelf. Supplement to: Sluijs, Appy; Bijl, Peter K; Schouten, Stefan; Röhl, Ursula; Reichart, Gert-Jan; Brinkhuis, Henk (2011): Southern ocean warming, sea level and hydrological change during the Paleocene-Eocene thermal maximum. Climate of the Past, 7(1), 47-61

In this study we have applied different indices based on long chain diols, i.e., the Long chain Diol Index (LDI) as proxy for past SST, the Diol Index as indicator of past upwelling conditions and the Nutrient Diol Index (NDI) as proxy for nitrate and phosphate concentrations in seawater. The proxies were analyzed in marine sediments recovered at ODP Site 1234, located within the Peru-Chile upwelling system, with a 2 kyr resolution, covering the last 150 kyrs. We also generated TEX^H^~86 and U_K'37 temperature and planktonic δ^18^O records, as well as total organic carbon (TOC) and accumulation rates (ARs) of TOC and lipid biomarkers (i.e., C~37~ alkenones, GDGTs, dinosterol and loliolide) to reconstruct past phytoplankton production. The LDI-derived SST record co-varies with TEX^H^86- and UK'37-derived SST records as well as with the planktonic δ^18^O record, implying that the LDI reflects past SST variations at this site. TOC and phytoplankton AR records indicate increased export production during the Last Interglacial (MIS 5), simultaneous with a peak in the abundance of preserved _Chaetoceros diatoms, suggesting intensified upwelling during this period. The Diol Index is relatively low during the upwelling period, but peaks before and after this period, suggesting that Proboscia diatoms were more abundant before and after the period of upwelling. The NDI reveals the same trends as the Diol Index suggesting that the input of nitrate and phosphate was minimal during upwelling, which is unrealistic. We suggest that the Diol Index and NDI should perhaps be considered as indicators for Proboscia productivity instead of upwelling conditions or nutrient concentrations. Supplement to: de Bar, Marijke W; Stolwijk, Dave; McManus, Jerry F; Sinninghe Damsté, Jaap S; Schouten, Stefan (2018): A Late Quaternary climate record based on long-chain diol proxies from the Chilean margin. Climate of the Past, 14(11), 1783-1803