A5049379993- Geology and Paleoclimatology Research
- Methane Hydrates and Related Phenomena
- Geological formations and processes
- Isotope Analysis in Ecology
- Hydrocarbon exploration and reservoir analysis
- Marine and coastal ecosystems
- Geological Studies and Exploration
- Geological and Geophysical Studies
- Marine and environmental studies
- Paleontology and Stratigraphy of Fossils
- Archaeology and ancient environmental studies
- Oceanographic and Atmospheric Processes
- Pleistocene-Era Hominins and Archaeology
- Maritime and Coastal Archaeology
- Atmospheric and Environmental Gas Dynamics
- Groundwater and Isotope Geochemistry
- Marine and fisheries research
- Arctic and Antarctic ice dynamics
- Climate change and permafrost
- Cryospheric studies and observations
- Pacific and Southeast Asian Studies
- Toxic Organic Pollutants Impact
- Geophysics and Gravity Measurements
- Ocean Acidification Effects and Responses
- Mineralogy and Gemology Studies
Kiel University
2014-2024
Faculty of 1000 (United States)
2021
National University of Tierra del Fuego
2021
Geological Institute
2008
Leibniz Institute for Baltic Sea Research
2004-2006
University of Rostock
2006
GEOMAR Helmholtz Centre for Ocean Research Kiel
2001
In this paper, we compile the current surface seawater C 37 alkenone unsaturation (U K′ ) measurements (n = 629, −1 to 30°C temperature range) derive a global, field‐based calibration of U with production temperature. A single nonlinear “global” water accurately predicts temperatures over diversity modern‐day oceanic environments and alkenone‐synthesizing populations (T −0.957 + 54.293(U − 52.894(U 2 28.321(U 3 , r 0.97, n 567). The mean standard error estimation is 1.2°C insignificant bias...
Particle flux data from 27 sites in the Atlantic Ocean have been compiled order to determine regional variations strength and efficiency of biological pump quantify carbon fluxes over ocean basin, thus estimating potential oceanic sequestration atmospheric CO 2 . An algorithm is derived relating annual particulate organic (POC) primary production depth that yields export ratio (ER = POC flux/primary production) at 125 m between 0.08 0.38 range 50 400 g C −2 yr −1 Significant differences...
Climate change is expected to result in smaller fish size, but the influence of fishing has made it difficult substantiate theorized link between size and ocean warming deoxygenation. We reconstructed community oceanographic conditions most recent global warm period (last interglacial; 130 116 thousand years before present) by using sediments from northern Humboldt Current system off coast Peru, a hotspot small pelagic productivity. In contrast present-day anchovy-dominated state, last...
We attempt a reconstruction of salinity levels the central Baltic Sea based on diatom assemblages, isotopic composition organic matter and sedimentological expression anoxia over last 10 000 years. use data to investigate dependence climate evolution isostasy. Changes in surface deep waters were most pronounced from 8400 approximately 5000 cal. BP. Density stratification between salty fresher caused frequent development anoxic conditions deposition laminated sediments large parts sea floor...
Research Article| October 01, 2009 Pliocene–Pleistocene variability of upwelling activity, productivity, and nutrient cycling in the Benguela region Johan Etourneau; Etourneau 1Institute for Geosciences, University Kiel, D-24118 Germany Search other works by this author on: GSW Google Scholar Philippe Martinez; Martinez 2UMR CNRS 5805 EPOC, Bordeaux 1, 33405 Talence, France Thomas Blanz; Blanz Ralph Schneider Author Article Information Publisher: Geological Society America Received: 10 Dec...
Abstract Millennial‐scale reductions in monsoon precipitation, so‐called Weak Monsoon Intervals (WMIs), have been identified numerous paleoclimate records across the Afro‐Asian domain throughout last glacial‐interglacial cycle. These are considered regional response to cooling during Heinrich events North Atlantic realm and several mechanisms suggested explain this hemisphere‐scale climatic teleconnection. In particular, Indian Ocean sea surface temperature (SST) proposed as linking element...
SignificanceUnderstanding the drivers of South Asian monsoon intensity is pivotal for improving climate forecasting under global warming scenarios. Solar insolation assumed to be dominant driver variability in warm regimes, but this has not been verified by proxy data. We report a rainfall record spanning last ∼130 kyr Ganges-Brahmaputra-Meghna river catchment. Our multiproxy data reveal that was weaker during Last Interglacial (130 115 ka)-despite higher insolation-than Holocene (11.6 ka...
[1] Studying past changes in the eastern equatorial Pacific Ocean dynamics and their impact on precipitation land gives us insight into how Intertropical Convergence Zone (ITCZ) movements El Niño-Southern Oscillation modulate regional global climate. In this study we present a multiproxy record of terrigenous input from marine sediments collected off Ecuadorian coast spanning last 500 kyr. parallel estimate sea surface temperatures (SST) derived alkenone paleothermometry for complement them...
Abstract Proxy records of hydrologic variability in the West Pacific Warm Pool (WPWP) have revealed wide‐scale changes past convective activity response to orbital and suborbital climate forcings. However, attributing proxy responses regional WPWP hydrology versus local variations precipitation requires independent linking terrestrial marine realms. We present high‐resolution stable isotope, U K′ 37 sea surface temperature, X‐ray fluorescence (XRF) core scanning, coccolithophore‐derived...
Research Article| September 01, 2009 A major and long-term Pliocene intensification of the Mediterranean outflow, 3.5–3.3 Ma ago Nabil Khélifi; Khélifi 1Institute Geosciences, University Kiel, D-24118 Germany Search for other works by this author on: GSW Google Scholar Michael Sarnthein; Sarnthein Germany4Institute Geology Paleontology, Innsbruck, A-6020 Austria Nils Andersen; Andersen 2Leibniz Laboratory Radiometric Dating Stable Isotope Research, Thomas Blanz; Blanz Martin Frank; Frank...
[1] Different proxies for sea surface temperature (SST) often exhibit divergent trends deglacial warming in tropical regions, hampering our understanding of the phase relationship between SSTs and continental ice volume at glacial terminations. To reconcile SST trends, we report reconstructions two commonly used paleothermometers (the foraminifera G. ruber Mg/Ca alkenone unsaturation index) from a marine sediment core collected southwestern Indian Ocean encompassing last 37,000 years. Our...
Abstract The response of the Humboldt Current System to future global warming is uncertain. Here we reconstruct alkenone‐derived near‐surface temperatures from multiple cores along Peruvian coast infer driving mechanisms upwelling changes for last 20 kyr. Our records show a deglacial consistent with Antarctic ice‐core and Mid‐Holocene cooling, which, in combination other paleoceanographic records, suggest strengthening conditions. This during globally warm Mid‐Holocene, an intensification...
Instrumental data evidence an accelerating freshwater release from Arctic sea ice export and the Greenland Ice Sheet over past three decades causing cooling freshening in subpolar North Atlantic region. However, evaluating observed acceleration on a historical oceanic climatic perspective remains challenging given short available instrumental time series. Here we provide marine releases to ocean since 1850 as reflected northern limb of Subpolar Gyre. Our reconstructions suggest that recent...
Measurements of the U 37 K′ index and absolute abundance alkenones in marine sediments are increasingly used paleoceanographic research as proxies past sea surface temperature haptophyte (mainly coccolith‐bearing species) primary productivity, respectively. An important aspect these studies is to be able compare reliably data obtained by different laboratories from a wide variety locations. Hence intercomparability produced community essential. Here we report results an anonymous...
We present alkenone‐derived Sea Surface Temperature (SST) records from three marine cores collected within the southern Benguela Upwelling System (BUS) spanning last 3 ka. The SST evolution over millennia is marked by aperiodic millennial‐scale oscillations that broadly correspond to climatic anomalies identified North Atlantic region. BUS data further suggest cooling and warming trends opposite temperature in Moroccan upwelling region Antarctica. In contrast, decades are a of unprecedented...
Reliable reconstruction of past sea surface temperature (SST) is prime importance for understanding the Earth’s sensitivity to external forcing. Yet, it remains a major challenge in paleoceanography because comparison between SST estimates from different proxies reveals mismatches and raise question as what contrasting actually record. A better these light seasonal occurrence proxy bearing organisms (archives) water mass changes help assess climate models. Here, we analyze data last...
Abstract. To assess the regional multi-decadal to multi-centennial climate variability along southern Iberian Peninsula during mid- late-Holocene record of paleo-environmental indicators from marine sediments were established for two sites in Alboran Sea (ODP-161-976A) and Gulf Cádiz (GeoB5901-2). High-resolution records organic geochemical properties planktic foraminiferal assemblages are used decipher precipitation vegetation changes as well hydrological conditions with respect sea surface...