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  1. Article: Paleoenvironmental response of midlatitudinal wetlands to Paleocene–early Eocene climate change (Schöningen lignite deposits, Germany)

    Methner, Katharina / Lenz, Olaf K.

    Climate of the past, 15(5):1741-1755

    2019  

    Abstract: The early Paleogene is marked by multiple negative carbon isotope excursions (CIEs) that reflect massive short-term carbon cycle perturbations that coincide with significant warming during a high-pCO2 world, affecting both marine and terrestrial ... ...

    Institution Senckenberg Gesellschaft für Naturforschung
    Abstract The early Paleogene is marked by multiple negative carbon isotope excursions (CIEs) that reflect massive short-term carbon cycle perturbations that coincide with significant warming during a high-pCO2 world, affecting both marine and terrestrial ecosystems. Records of such hyperthermals from the marine–terrestrial interface (e.g., estuarine swamps and mire deposits) are therefore of great interest as their present-day counterparts are highly vulnerable to future climate and sea level change. Here, we assess paleoenvironmental changes of midlatitudinal late Paleocene–early Eocene peat mire records along the paleo-North Sea coast. We provide carbon isotope data of bulk organic matter (δ13CTOC), organic carbon content (%TOC), and palynological data from an extensive peat mire deposited at a midlatitudinal (ca. 41∘ N) coastal site (Schöningen, Germany). The δ13CTOC data show a carbon isotope excursion of −1.3 ‰ (mean decrease in δ13CTOC; −1.7 ‰ at the onset of CIE) coeval with a conspicuous Apectodinium acme. Due to the exceptionally large stratigraphic thickness of the CIE at Schöningen (10 m of section) we established a detailed palynological record that indicates only minor changes in paleovegetation leading into and during this event. Instead, paleovegetation changes mostly follow natural successions in response to changes along the marine–terrestrial interface. The available age constraints for the Schöningen Formation hamper a solid assignment of the detected CIE to a particular hyperthermal such as the Paleocene–Eocene Thermal Maximum (PETM) or any succeeding hyperthermal event such as the Eocene Thermal Maximum 2 (ETM2). Compared to other nearby peat mire records (Cobham, UK; Vasterival, F) it appears that wetland deposits around the Paleogene North Sea have a consistent CIE magnitude of ca. −1.3 ‰ in δ13CTOC. Moreover, the Schöningen record shares major characteristics with the Cobham Lignite PETM record, including evidence for increased fire activity prior to the CIE, minor plant species change during the hyperthermal, a reduced CIE in δ13CTOC, and drowning of the mire (marine ingressions) during much of the Schöningen CIE event. This suggests that either the Schöningen CIE reflects the PETM or that early Paleogene hyperthermals similarly affected paleoenvironmental conditions of a major segment of the paleo-North Sea coast.
    Language English
    Document type Article
    Database Repository for Life Sciences

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  2. Article ; Online: Middle Miocene long-term continental temperature change in and out of pace with marine climate records.

    Methner, Katharina / Campani, Marion / Fiebig, Jens / Löffler, Niklas / Kempf, Oliver / Mulch, Andreas

    Scientific reports

    2020  Volume 10, Issue 1, Page(s) 7989

    Abstract: Reconstructing long-term continental temperature change provides the required counterpart to age equivalent marine records and can reveal how terrestrial and marine temperatures were related during times of extreme climate change such as the Miocene ... ...

    Abstract Reconstructing long-term continental temperature change provides the required counterpart to age equivalent marine records and can reveal how terrestrial and marine temperatures were related during times of extreme climate change such as the Miocene Climatic Optimum (MCO) and the following Middle Miocene Climatic Transition (MMCT). Carbonate clumped isotope temperatures (T(Δ
    Language English
    Publishing date 2020-05-14
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-020-64743-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Book ; Online: The effects of diachronous surface uplift of the European Alps on regional climate and the oxygen isotopic composition of precipitation

    Boateng, Daniel / Mutz, Sebastian G. / Ballian, Armelle / Meijers, Maud J. M. / Methner, Katharina / Botsyun, Svetlana / Mulch, Andreas / Ehlers, Todd A.

    eISSN: 2190-4987

    2023  

    Abstract: This study presents the simulated response of regional climate and the oxygen isotopic composition of precipitation ( δ 18 O p ) to different along-strike topographic evolution scenarios. These simulations are conducted to determine if the previously ... ...

    Abstract This study presents the simulated response of regional climate and the oxygen isotopic composition of precipitation ( δ 18 O p ) to different along-strike topographic evolution scenarios. These simulations are conducted to determine if the previously hypothesized diachronous surface uplift in the Western and Eastern Alps would produce δ 18 O p signals in the geologic record that are sufficiently large and distinct to be detected using stable isotope paleoaltimetry. We present a series of topographic sensitivity experiments conducted with the water-isotope-tracking atmospheric general circulation model (GCM) ECHAM5-wiso. The topographic scenarios are created from the variation of two free parameters, (1) the elevation of the Western–Central Alps and (2) the elevation of the Eastern Alps. The results indicate Δ δ 18 O p values (i.e., the difference between δ 18 O p values at the low- and high-elevation sites) of up to −8 ‰ along the strike of the Alps for the diachronous uplift scenarios, primarily due to changes in orographic precipitation and adiabatic lapse rate driven localized changes in near-surface variables. These simulated magnitudes of Δ δ 18 O p values suggest that the expected isotopic signal would be significant enough to be preserved and measured in geologic archives. Moreover, the simulated slight δ 18 O p differences of 1 ‰–2 ‰ across the low-elevation sites support the use of the δ – δ paleoaltimetry approach and highlight the importance of sampling far-field low-elevation sites to differentiate between the different surface uplift scenarios. The elevation-dependent rate of change in δ 18 O p (“isotopic lapse rate”) varies depending on the topographic configuration and the extent of the surface uplift. Most of the changes are significant (e.g., −1.04 ‰ km −1 change with slope error of ±0.09 ‰ km −1 ), while others were within the range of the statistical uncertainties (e.g., −0.15 ‰ km −1 change with slope error of ±0.13 ‰ km −1 ). The results also highlight the plausible changes in atmospheric ...
    Subject code 333 ; 511
    Language English
    Publishing date 2023-11-17
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Subglacial precipitates record Antarctic ice sheet response to late Pleistocene millennial climate cycles.

    Piccione, Gavin / Blackburn, Terrence / Tulaczyk, Slawek / Rasbury, E Troy / Hain, Mathis P / Ibarra, Daniel E / Methner, Katharina / Tinglof, Chloe / Cheney, Brandon / Northrup, Paul / Licht, Kathy

    Nature communications

    2022  Volume 13, Issue 1, Page(s) 5428

    Abstract: Ice cores and offshore sedimentary records demonstrate enhanced ice loss along Antarctic coastal margins during millennial-scale warm intervals within the last glacial termination. However, the distal location and short temporal coverage of these records ...

    Abstract Ice cores and offshore sedimentary records demonstrate enhanced ice loss along Antarctic coastal margins during millennial-scale warm intervals within the last glacial termination. However, the distal location and short temporal coverage of these records leads to uncertainty in both the spatial footprint of ice loss, and whether millennial-scale ice response occurs outside of glacial terminations. Here we present a >100kyr archive of periodic transitions in subglacial precipitate mineralogy that are synchronous with Late Pleistocene millennial-scale climate cycles. Geochemical and geochronologic data provide evidence for opal formation during cold periods via cryoconcentration of subglacial brine, and calcite formation during warm periods through the addition of subglacial meltwater originating from the ice sheet interior. These freeze-flush cycles represent cyclic changes in subglacial hydrologic-connectivity driven by ice sheet velocity fluctuations. Our findings imply that oscillating Southern Ocean temperatures drive a dynamic response in the Antarctic ice sheet on millennial timescales, regardless of the background climate state.
    Language English
    Publishing date 2022-09-15
    Publishing country England
    Document type Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-022-33009-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Book ; Online: Paleoenvironmental response of midlatitudinal wetlands to Paleocene–early Eocene climate change (Schöningen lignite deposits, Germany)

    Methner, Katharina / Lenz, Olaf / Riegel, Walter / Wilde, Volker / Mulch, Andreas

    eISSN: 1814-9332

    2019  

    Abstract: The early Paleogene is marked by multiple negative carbon isotope excursions (CIEs) that reflect massive short-term carbon cycle perturbations that coincide with significant warming during a high- p CO 2 world, affecting both marine and terrestrial ... ...

    Abstract The early Paleogene is marked by multiple negative carbon isotope excursions (CIEs) that reflect massive short-term carbon cycle perturbations that coincide with significant warming during a high- p CO 2 world, affecting both marine and terrestrial ecosystems. Records of such hyperthermals from the marine–terrestrial interface (e.g., estuarine swamps and mire deposits) are therefore of great interest as their present-day counterparts are highly vulnerable to future climate and sea level change. Here, we assess paleoenvironmental changes of midlatitudinal late Paleocene–early Eocene peat mire records along the paleo-North Sea coast. We provide carbon isotope data of bulk organic matter ( δ 13 C TOC ), organic carbon content (%TOC), and palynological data from an extensive peat mire deposited at a midlatitudinal (ca. 41 ∘ N) coastal site (Schöningen, Germany). The δ 13 C TOC data show a carbon isotope excursion of −1.3 ‰ (mean decrease in δ 13 C TOC

    −1.7 ‰ at the onset of CIE) coeval with a conspicuous Apectodinium acme. Due to the exceptionally large stratigraphic thickness of the CIE at Schöningen (10 m of section) we established a detailed palynological record that indicates only minor changes in paleovegetation leading into and during this event. Instead, paleovegetation changes mostly follow natural successions in response to changes along the marine–terrestrial interface. The available age constraints for the Schöningen Formation hamper a solid assignment of the detected CIE to a particular hyperthermal such as the Paleocene–Eocene Thermal Maximum (PETM) or any succeeding hyperthermal event such as the Eocene Thermal Maximum 2 (ETM2). Compared to other nearby peat mire records (Cobham, UK; Vasterival, F) it appears that wetland deposits around the Paleogene North Sea have a consistent CIE magnitude of ca. −1.3 ‰ in δ 13 C TOC . Moreover, the Schöningen record shares major characteristics with the Cobham Lignite PETM record, including evidence for increased fire activity prior to the CIE, minor plant species change during the hyperthermal, a reduced CIE in δ 13 C TOC , and drowning of the mire (marine ingressions) during much of the Schöningen CIE event. This suggests that either the Schöningen CIE reflects the PETM or that early Paleogene hyperthermals similarly affected paleoenvironmental conditions of a major segment of the paleo-North Sea coast.
    Subject code 333 ; 511
    Language English
    Publishing date 2019-09-16
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Book ; Online: Palaeoenvironmental response of mid-latitudinal wetlands to PETM climate change (Schöningen lignite deposits, Germany)

    Methner, Katharina / Lenz, Olaf / Riegel, Walter / Wilde, Volker / Mulch, Andreas

    eISSN: 1814-9332

    2019  

    Abstract: The Paleocene-Eocene Thermal Maximum (PETM) offers insight into massive short-term carbon cycle perturbations that caused significant warming during a high-pCO 2 world, affecting both marine and terrestrial ecosystems. PETM records from the marine- ... ...

    Abstract The Paleocene-Eocene Thermal Maximum (PETM) offers insight into massive short-term carbon cycle perturbations that caused significant warming during a high-pCO 2 world, affecting both marine and terrestrial ecosystems. PETM records from the marine-terrestrial interface (e.g. estuarine swamps and mire deposits) are, therefore, of great interest as their present-day counterparts are highly vulnerable to future climate and sea level change. Here, we assess paleoenvironmental changes of mid-latitudinal Late Paleocene-Early Eocene peat mire records along the paleo-North Sea coast. We provide carbon isotope data of bulk organic matter (δ 13 C TOC ), organic carbon content (%TOC), and palynological data from an extensive peat mire deposited at a mid-latitudinal (ca. 41 °N) coastal site (Schöningen, Germany). The δ 13 C TOC data show a carbon isotope excursion (CIE) of −1.7 ‰ coeval with a conspicuous Apectodinium acme, calling for the presence of the PETM in this coastal section. Due to the exceptionally large stratigraphic thickness of the PETM at Schöningen (10 m of section) we established a detailed palynological record that indicates only minor changes in paleovegetation leading to and during the PETM. Instead, paleovegetation changes mostly follow natural successions in response to changes along the marine-terrestrial interface. Compared to other available peat mire records (Cobham, UK; Vasterival, France) it appears that wetland deposits around the Paleogene North Sea have a typical CIE magnitude of ca. −1.3 ‰ in δ 13 C TOC . Moreover, the Schöningen record shares major characteristics with the Cobham Lignite, including evidence for increased fire activity prior to the PETM, minor PETM-related plant species changes, a reduced CIE in δ 13 C TOC , and drowning of the mire (marine ingressions) during much of the PETM. This suggests that paleoenvironmental conditions during the Late Paleocene-Early Eocene, including the PETM, consistently affected major segments of the paleo-North Sea coast.
    Subject code 333
    Language English
    Publishing date 2019-02-14
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Book ; Online ; Thesis: Recovering Eocene paleotopography and paleoclimate of the North American Cordillera through integrated stable isotope and clumped isotope analyses

    Methner, Katharina [Verfasser] / Mulch, Andreas [Gutachter] / Chamberlain, C. Page [Gutachter]

    2016  

    Author's details Katharina Methner ; Gutachter: Andreas Mulch, C. Page Chamberlain
    Keywords Geowissenschaften ; Earth Sciences
    Subject code sg550
    Language English
    Publisher Universitätsbibliothek Johann Christian Senckenberg
    Publishing place Frankfurt am Main
    Document type Book ; Online ; Thesis
    Database Digital theses on the web

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  8. Article ; Online: Slight pressure imbalances can affect accuracy and precision of dual inlet-based clumped isotope analysis.

    Fiebig, Jens / Hofmann, Sven / Löffler, Niklas / Lüdecke, Tina / Methner, Katharina / Wacker, Ulrike

    Isotopes in environmental and health studies

    2016  Volume 52, Issue 1-2, Page(s) 12–28

    Abstract: It is well known that a subtle nonlinearity can occur during clumped isotope analysis of CO2 that - if remaining unaddressed - limits accuracy. The nonlinearity is induced by a negative background on the m/z 47 ion Faraday cup, whose magnitude is ... ...

    Abstract It is well known that a subtle nonlinearity can occur during clumped isotope analysis of CO2 that - if remaining unaddressed - limits accuracy. The nonlinearity is induced by a negative background on the m/z 47 ion Faraday cup, whose magnitude is correlated with the intensity of the m/z 44 ion beam. The origin of the negative background remains unclear, but is possibly due to secondary electrons. Usually, CO2 gases of distinct bulk isotopic compositions are equilibrated at 1000 °C and measured along with the samples in order to be able to correct for this effect. Alternatively, measured m/z 47 beam intensities can be corrected for the contribution of secondary electrons after monitoring how the negative background on m/z 47 evolves with the intensity of the m/z 44 ion beam. The latter correction procedure seems to work well if the m/z 44 cup exhibits a wider slit width than the m/z 47 cup. Here we show that the negative m/z 47 background affects precision of dual inlet-based clumped isotope measurements of CO2 unless raw m/z 47 intensities are directly corrected for the contribution of secondary electrons. Moreover, inaccurate results can be obtained even if the heated gas approach is used to correct for the observed nonlinearity. The impact of the negative background on accuracy and precision arises from small imbalances in m/z 44 ion beam intensities between reference and sample CO2 measurements. It becomes the more significant the larger the relative contribution of secondary electrons to the m/z 47 signal is and the higher the flux rate of CO2 into the ion source is set. These problems can be overcome by correcting the measured m/z 47 ion beam intensities of sample and reference gas for the contributions deriving from secondary electrons after scaling these contributions to the intensities of the corresponding m/z 49 ion beams. Accuracy and precision of this correction are demonstrated by clumped isotope analysis of three internal carbonate standards. The proposed correction scheme can be easily applied if the slit width of the m/z 49 Faraday cup is bigger than that of the m/z 47 cup.
    MeSH term(s) Carbon/analysis ; Carbon Dioxide/analysis ; Carbon Isotopes/analysis ; Carbonates/analysis ; Mass Spectrometry/methods ; Oxygen/analysis ; Oxygen Isotopes/analysis ; Pressure
    Chemical Substances Carbon Isotopes ; Carbonates ; Oxygen Isotopes ; Carbon Dioxide (142M471B3J) ; Carbon (7440-44-0) ; Oxygen (S88TT14065)
    Language English
    Publishing date 2016
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2100190-X
    ISSN 1477-2639 ; 1025-6016
    ISSN (online) 1477-2639
    ISSN 1025-6016
    DOI 10.1080/10256016.2015.1010531
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Dual clumped isotope thermometry resolves kinetic biases in carbonate formation temperatures.

    Bajnai, David / Guo, Weifu / Spötl, Christoph / Coplen, Tyler B / Methner, Katharina / Löffler, Niklas / Krsnik, Emilija / Gischler, Eberhard / Hansen, Maximilian / Henkel, Daniela / Price, Gregory D / Raddatz, Jacek / Scholz, Denis / Fiebig, Jens

    Nature communications

    2020  Volume 11, Issue 1, Page(s) 4005

    Abstract: Surface temperature is a fundamental parameter of Earth's climate. Its evolution through time is commonly reconstructed using the oxygen isotope and the clumped isotope compositions of carbonate archives. However, reaction kinetics involved in the ... ...

    Abstract Surface temperature is a fundamental parameter of Earth's climate. Its evolution through time is commonly reconstructed using the oxygen isotope and the clumped isotope compositions of carbonate archives. However, reaction kinetics involved in the precipitation of carbonates can introduce inaccuracies in the derived temperatures. Here, we show that dual clumped isotope analyses, i.e., simultaneous ∆
    Language English
    Publishing date 2020-08-10
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-020-17501-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Book ; Online: Miocene high elevation and high relief in the Central Alps

    Krsnik, Emilija / Methner, Katharina / Campani, Marion / Botsyun, Svetlana / Mutz, Sebastian G. / Ehlers, Todd A. / Kempf, Oliver / Fiebig, Jens / Schlunegger, Fritz / Mulch, Andreas

    eISSN: 1869-9529

    2021  

    Abstract: Reconstructing Oligocene-Miocene paleoelevation contributes to our understanding of the evolutionary history of the European Alps and sheds light on geodynamic and Earth’s surface processes involved in the development of Alpine topography. Despite being ... ...

    Abstract Reconstructing Oligocene-Miocene paleoelevation contributes to our understanding of the evolutionary history of the European Alps and sheds light on geodynamic and Earth’s surface processes involved in the development of Alpine topography. Despite being one of the most intensively explored mountain ranges worldwide, constraints on the elevation history of the European Alps, however, remain scarce. Here we present stable and clumped isotope geochemistry measurements to provide a new paleoelevation estimate for the mid-Miocene (~14.5 Ma) European Central Alps. We apply stable isotope δ-δ paleoaltimetry on near sea level pedogenic carbonate oxygen isotope (δ 18 O) records from the Northern Alpine Foreland Basin (Swiss Molasse Basin) and high-Alpine phyllosilicate hydrogen isotope (δD) records from the Simplon Fault Zone (Swiss Alps). We further explore Miocene paleoclimate and paleoenvironmental conditions in the Swiss Molasse Basin through carbonate stable (δ 18 O, δ 13 C) and clumped (Δ 47 ) isotope data from three foreland basin sections in different alluvial megafan settings (proximal, mid-fan, and distal). Combined pedogenic carbonate δ 18 O values and Δ 47 temperatures (30 ± 5 °C) yield a near sea level precipitation δ 18 O w value of −5.8 ± 0.2 ‰ and in conjunction with the high-Alpine phyllosilicate δD record suggest that the region surrounding the SFZ attained surface elevations of > 4000 m no later than the mid-Miocene. Our near sea level δ 18 O w estimate is supported by paleoclimate (iGCM Echam5-wiso) modeled δ 18 O values, which vary between −4.2 and −7.6 ‰ for the Northern Alpine Foreland Basin.
    Subject code 333
    Language English
    Publishing date 2021-05-31
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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