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  • Abstract: We present a 47-year-long record of sea surface temperature (SST) derived from Sr/Ca and U/Ca analysis of a massive Porites coral which grew at ~4150 calendar years before present (B.P.) in Vanuatu (southwest tropical Pacific Ocean). Mean SST is similar in both the modern instrumental record and paleorecord, and both exhibit El Niño-Southern Oscillation (ENSO) frequency SST oscillations. However, several strong decadal-frequency cooling events and a marked modulation of the seasonal SST cycle, with power at both ENSO and decadal frequencies, are observed in the paleorecord, which are unprecedented in the modern record. Category: geoscientificInformation Source: Supplement to: Corrège, Thierry; Delcroix, Thierry; Recy, Jacques; Beck, Warren; Cabioch, Guy; Le Cornec, Florence (2000): Evidence for stronger El Niño-Southern Oscillation (ENSO) Events in a Mid-Holocene massive coral. Paleoceanography, 15(4), 465-470, https://doi.org/10.1029/1999PA000409 Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: -15.670000 * LONGITUDE: 167.000000 * ELEVATION: 4.7 m * METHOD|DEVICE: Core drilling
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  • Abstract: Paleoenvironmental proxy data for ocean properties, eolian sediment input, and continental rainfall based on high-resolution analyses of sediment cores from the southwestern Black Sea and the northernmost Gulf of Aqaba were used to infer hydroclimatic changes in northern Anatolia and the northern Red Sea region during the last ~7500 years. Pronounced and coherent multicentennial variations in these records reveal patterns that strongly resemble modern temperature and rainfall anomalies related to the Arctic Oscillation/North Atlantic Oscillation (AO/NAO). These patterns suggest a prominent role of AO/NAO-like atmospheric variability during the Holocene beyond interannual to interdecadal timescales, most likely originating from solar output changes. Category: geoscientificInformation Source: Supplement to: Lamy, Frank; Arz, Helge Wolfgang; Bond, Gerard C; Bahr, André; Pätzold, Jürgen (2006): Multicentennial-scale hydrological changes in the Black Sea and northern Red Sea during the Holocene and the Arctic/North Atlantic Oscillation. Paleoceanography, 21(1), PA1008, https://doi.org/10.1029/2005PA001184 Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 29.501700 * LONGITUDE: 34.956700 * DATE/TIME: 1999-03-13T11:23:00 * ELEVATION: -464.0 m * Recovery: 3.43 m * LOCATION: Gulf of Aqaba * CAMPAIGN: M44/3 * BASIS: Meteor (1986) * METHOD/DEVICE: Gravity corer (Kiel type) EVENT LABEL: (633) * LATITUDE: 41.535000 * LONGITUDE: 31.166667 * DATE/TIME: 2001-12-25T14:04:00 * ELEVATION: -1306.0 m * Recovery: 7.68 m * LOCATION: SW Black Sea * CAMPAIGN: M51/4 * BASIS: Meteor (1986) * METHOD/DEVICE: Gravity corer (Kiel type) EVENT LABEL: (636) * LATITUDE: 41.445000 * LONGITUDE: 31.066667 * DATE/TIME: 2001-12-26T13:57:00 * ELEVATION: -1242.0 m * Recovery: 7.92 m * LOCATION: SW Black Sea * CAMPAIGN: M51/4 * BASIS: Meteor (1986) * METHOD/DEVICE: Gravity corer (Kiel type)
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  • Abstract: We investigate the long-term stability of El Niño-Southern Oscillation and Pacific Decadal Oscillation based on the examination of coccolithophore assemblages in a largely laminated 35 ka sedimentary record, retrieved in the Santa Barbara Basin (core MD02-2503). At a centennial scale coccolith assemblages indicate low primary production in the basin from 35 to 11.5 ka B.P., whereas the Holocene is characterized by high-productivity conditions. This pattern demonstrates the influence of the glacial-interglacial cycles on productivity and, by inference, on the nutrient supply by the upwelling cell off Point of Conception. On a shorter scale, laminations associated with Dansgaard-Oeschger events appear to be due to an injection of poorly oxygenated waters in the deepest part of the basin rather than anoxia due to high primary production. A seasonal sampling in seven laminated sections (spanning from 20 to 220 years) extracted from Holocene, Bølling-Allerød, and Dansgaard-Oeschger event 3 indicates El Niño probably existed continuously during the last 28 ka. The frequency of El Niño varied through time (between 1/2.5 and 1/5 event/a) and appearing to follow the precession cycle. El Niño exhibits higher (lower) frequencies when the precession values are lower (higher). Finally, the Holocene is characterized by a decrease in El Niño's frequencies due to the reinforcement of El Niño through this period. Category: geoscientificInformation Source: Supplement to: Grelaud, Michaël; Beaufort, Luc; Cuven, Stéphanie; Buchet, Noëlle (2009): Glacial to interglacial primary production and El Niño-Southern Oscillation dynamics inferred from coccolithophores of the Santa Barbara Basin. Paleoceanography, 24(1), PA1203, https://doi.org/10.1029/2007PA001578 Supplemental Information: Not Availble Coverage: Not Available
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  • Climate variability and El Niño Southern Oscillation... Frequency [%]... Frequency/ind [#/#]
    Data Types:
    • Tabular Data
    • Dataset
  • Abstract: Stable isotopic measurements of G. sacculifer and C. wuellerstorfi in a core from the western equatorial Atlantic imply that there are parallel, suborbital oscillations in surface water hydrography and deep water circulation occurring during oxygen isotope stages 2 and 3. Low values of G. sacculifer delta18O accompany high values of C. wuellerstorfi delta13C, linking warmer sea surface temperatures (SSTs) in the tropics with increased production of lower North Atlantic Deep Water (NADW). The amplitude of the delta18O oscillations is 0.6 per mil (or 2°-3°C), which is superimposed on a glacial/interglacial amplitude of about 2.1per mil. Using the G. sacculifer delta18O data, we calculate that surface waters were colder during stage 2 than calculated by CLIMAP [1976, 1981]. The longer-period (>2 kyr) oscillations in air temperature recorded in the Greenland and Antarctic ice cores appear to correlate with oscillations in sea surface temperature in the equatorial Atlantic. The magnitude of these oscillations in tropical SST is too large to have resulted from changes in meridional heat transport caused by the global conveyor alone. The apparent synchroneity of equatorial SST and polar air temperature changes, as well as the amplitude of the SST changes at the equator, are consistent with the climate effects expected from changes in the atmosphere's greenhouse gas content (H2Ovapor, CO2, and CH4). Category: geoscientificInformation Source: Supplement to: Curry, William B; Oppo, Delia W (1997): Synchronous, high-frequency oscillations in tropical sea surface temperatures and North Atlantic Deep Water productivity during the last glacial cycle. Paleoceanography, 12(1), 1-14, https://doi.org/10.1029/96PA02413 Supplemental Information: Not Availble Coverage: EVENT LABEL: * LATITUDE: 5.906700 * LONGITUDE: -44.195000 * ELEVATION START: -4056.0 m * ELEVATION END: 0.0 m * Recovery: 6 m * METHOD|DEVICE: Piston corer
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  • Abstract: This paper presents physical and nutrient results from the Etude du Broutage en Zone Equatoriale cruise, conducted in the equatorial Pacific along the 180° meridian from 8°S to 8°N. Cold conditions of the El Niño-Southern Oscillation cycle were evident during the cruise (October-November 1996), and the equatorial upwelling was in its far western extension. Along the sampled section the nutrient-enriched area was asymmetric around the equator, and a zone of high remineralization was found from 6° to 3°S. Intensive sampling at two 5-day time series stations (3°S and 0°) provided some insight on high-frequency variability. At 3°S a deep density mixed layer showed only small fluctuations in nutrients. On the equator a rapid reduction of surface nutrients during the time series station was attributed to advection of a different water mass from the northeast, in the southward branch of a Tropical Instability Wave (TIW). Measurements from the Tropical Atmosphere-Ocean (TAO) array in the area confirmed significant contemporaneous TIW activity, which was linked to the cold conditions. Thus, in contrast to previous observations, it is shown that TIWs can contribute to relative decrease of nutrients at the equator. During the two time series sampling efforts, variability at diurnal and semidiurnal periods were found in physical parameters, originating from surface atmospheric forcing and internal wave activity at tidal frequency, respectively. In the 0-150 m layer, where intensive sampling of nutrients was performed, high-frequency variability did not seem to modify nutrient distribution significantly and physical influences dominated over biology. Category: geoscientificInformation Source: Supplement to: Eldin, Gérard; Rodier, Martine (2003): Ocean physics and nutrient fields along 180° during an El Niño-Southern Oscillation cold phase. Journal of Geophysical Research: Oceans, 108(C12), 8137, https://doi.org/10.1029/2000JC000746 Supplemental Information: Not Availble Coverage: Not Available
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    • File Set
  • Climate variability and El Niño Southern Oscillation... Frequency [%]... Frequency [#]
    Data Types:
    • Tabular Data
    • Dataset
  • Abstract: Transport studies that employ column experiments in closed-flow mode complement classical approaches by providing new characteristic features observed in the breakthrough behavior and an equilibrium between liquid and solid phase. Specific to the closed-flow mode is the recirculation of the column effluent to the inflow via a mixing vessel. Depending on the ratio of volume of the water-filled pore space to the volume of the mixing vessel, a damped oscillating solute concentration emerges in effluent and mixing vessel. Oscillation frequency, extent of damping and amplitude are thereby governed by the transport properties of the porous medium. These characteristics allow for the analysis of transport processes in soils in a similar fashion as known for classical open-flow column experiments. However, the experimental design considers feedbacks of liquid solid interactions by connecting the effluent solution with the inflow. In this way, solute and porous medium can equilibrate with respect to all physicochemical parameters, thereby permitting a convenient consideration of mass balances. With this paper, the features emerging in the breakthrough of column experiments run in closed-flow mode and methods of evaluation are illustrated under experimental boundary conditions forcing the appearance of these oscillations. Additionally, the effect of flow velocity and mixing vessel volume on the breakthrough is investigated. We demonstrate that the water content of the porous medium and the pumping rate can be determined from a conservative tracer breakthrough curve. In this way, external preconditioning of the soil material, e.g., drying, can be avoided. This renders the closed-flow column approach especially interesting for the study of porous media with diverse mineral content and bacterial community that react strongly on changes in the water content. Furthermore, the basis for the modeling of closed-flow experiments is given by the derivation of constitutive equations and numerical implementation, validated by the presented experiments. Category: geoscientificInformation Source: Supplement to: Ritschel, Thomas; Totsche, Kai Uwe (2016): Closed-flow column experiments - insights into solute transport provided by a damped oscillating breakthrough behavior. Water Resources Research, 52(3), 2206-2221, https://doi.org/10.1002/2015WR018317 Supplemental Information: Not Availble Coverage: Not Available
    Data Types:
    • Dataset
    • File Set
  • Climate variability and El Niño Southern Oscillation... Frequency [#]
    Data Types:
    • Tabular Data
    • Dataset
  • Abstract: A winter (DJFM) North Atlantic Oscillation index (NAOi) has been reconstructed over the peridod 1781-1996 by calibrating the winter frequencies of Lamb weather types to the winter PC-based NAOi of Hurrell (1995, doi:10.1126/science.269.5224.676). The data file contains 4 columns: year of JFM, NAOi, uncertainty (1 std), number of unclassified days over this winter. The NAOi has no unit since regressed to a normalised index. Note that this index has not been renormalised (to an average value of zero and standard deviation of 1). The number of unclassified days directly affects the reliability and consistency of the NAOi. For instance, Delaygue et al. (2018) require less than 24 unclassified days per winter to consider the NAOi. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: Not Available
    Data Types:
    • Tabular Data
    • Dataset