A5069698611- Geology and Paleoclimatology Research
- Stellar, planetary, and galactic studies
- Atmospheric and Environmental Gas Dynamics
- Methane Hydrates and Related Phenomena
- Cryospheric studies and observations
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Isotope Analysis in Ecology
- Solar and Space Plasma Dynamics
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Atmospheric chemistry and aerosols
- History and Developments in Astronomy
- Atmospheric Ozone and Climate
- Pleistocene-Era Hominins and Archaeology
- Hydrocarbon exploration and reservoir analysis
- Astrophysics and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Climate change and permafrost
- Marine and coastal ecosystems
- Geomagnetism and Paleomagnetism Studies
- Geophysics and Gravity Measurements
- Nuclear Physics and Applications
Oeschger Centre for Climate Change Research
2016-2025
University of Bern
2016-2025
Universität Hamburg
2001-2020
Medizinisch Wissenschaftliche Verlagsgesellschaft (Germany)
2019
Hamburger Fern-Hochschule
2001-2016
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2003-2014
University Hospital Carl Gustav Carus
2012
Hamburg Institut (Germany)
2010
British Antarctic Survey
2008
University of Copenhagen
2008
Abstract The European Project for Ice Coring in Antarctica Dome ice core from C (EDC) has allowed the reconstruction of atmospheric CO 2 concentrations last 800,000 years. Here we revisit oldest part EDC record using different air extraction methods and sections core. For our established cracker system, found an analytical artifact, which increases over deepest 200 m reaches 10.1 ± 2.4 ppm oldest/deepest part. governing mechanism is not yet fully understood, but it related to insufficient...
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the primary instrument on Spectrum-Roentgen-Gamma (SRG) mission, which was successfully launched July 13, 2019, from Baikonour cosmodrome. After commissioning of and a subsequent calibration performance verification phase, started survey entire sky December 2019. By end 2023, eight complete scans celestial sphere will have been performed, each lasting six months. At this program, all-sky in soft X-ray band (0.2--2.3\,keV)...
This paper presents new maps of the soft X-ray background from ROSAT all-sky survey. These represent a significant improvement over previous version in that (1) position resolution PSPC has been used to improve angular ~2° 12', (2) there are six energy bands divide each three into two parts, and (3) contributions point sources have removed uniform source flux level most sky. will be available electronic format later 1997.
The stable carbon isotope ratio of atmospheric CO(2) (δ(13)C(atm)) is a key parameter in deciphering past cycle changes. Here we present δ(13)C(atm) data for the 24,000 years derived from three independent records two Antarctic ice cores. We conclude that pronounced 0.3 per mil decrease during early deglaciation can be best explained by upwelling old, carbon-enriched waters Southern Ocean. Later deglaciation, regrowth terrestrial biosphere, changes sea surface temperature, and ocean...
Abstract. Continuous records of the atmospheric greenhouse gases (GHGs) CO2, CH4, and N2O are necessary input data for transient climate simulations, their associated radiative forcing represents important components in analyses sensitivity feedbacks. Since available from ice cores discontinuous partly ambiguous, a well-documented decision process during compilation followed by some interpolating post-processing is to obtain those desired time series. Here, we document our best possible...
Abstract Atmospheric methane's rapid growth from late 2006 is unprecedented in the observational record. Assessment of atmospheric methane data attributes a large fraction this to increased natural emissions over tropics, which appear be responding changes anthropogenic climate forcing. Isotopically lighter measurements are consistent with recent being mainly driven by an increase microbial sources, particularly wetlands. The global budget currently disequilibrium and new inputs as yet...
view Abstract Citations (270) References (31) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS First Maps of the Soft X-Ray Diffuse Background from ROSAT XRT/PSPC All-Sky Survey Snowden, S. L. ; Freyberg, M. J. Plucinsky, P. Schmitt, H. Truemper, Voges, W. Edgar, R. McCammon, D. Sanders, T. This paper presents an initial version diffuse background results ROSA T soft X-ray all-sky survey. These maps cover ∼98% sky in ¼ keV, ¾ and 1.5 keV bands, with ∼2°...
Continuous flow analysis (CFA) is a well-established method to obtain information about impurity contents in ice cores as indicators of past changes the climate system. A section an core continuously melted on melter head supplying sample water which analyzed online. This provides high depth and time resolution records very efficient decontamination only inner part analyzed. Here we present improved CFA system has been totally redesigned view significantly enhanced overall efficiency...
Abstract. The reconstruction of the stable carbon isotope evolution in atmospheric CO2 (δ13Catm), as archived Antarctic ice cores, bears potential to disentangle contributions different cycle fluxes causing past variations. Here we present a new record δ13Catm before, during and after Marine Isotope Stage 5.5 (155 000 105 yr BP). dataset is on data repository PANGEA® (www.pangea.de) under 10.1594/PANGAEA.817041. was derived with well established sublimation method using from EPICA Dome C...
Abstract We present new δ 13 C measurements of atmospheric CO 2 covering the last glacial/interglacial cycle, complementing previous records Terminations I and II. Most prominent in record is a significant depletion C(atm) 0.5‰ occurring during marine isotope stage (MIS) 4, followed by an enrichment same magnitude at beginning MIS 3. Such excursion otherwise only observed glacial terminations, suggesting that similar processes were play, such as changing sea surface temperatures, changes...
Numerical models are important tools for understanding the processes and feedbacks in Earth system, including those involving changes atmospheric CO2 (CO2,atm) concentrations. Here, we compile 55 published model studies (consisting of 778 individual simulations) that assess impact six forcing mechanisms on millennial-scale CO2,atm variations: freshwater supply to North Atlantic Southern Ocean, strength position southern-hemisphere westerlies, Antarctic sea ice extent, aeolian dust fluxes. We...
Significance Earth’s radiative imbalance determines whether energy is flowing into or out of the ocean–atmosphere system. The present, anthropogenic, positive drives global warming. This study reconstructs for last deglaciation, ∼20,000 to 10,000 y ago. During a was maintained several thousand years, which brought climate system from ice age Holocene warm period. We show that varied significantly during this time, possibly due changes in ocean circulation affect fluxes, highlighting...
Permafrost and methane hydrates are large, climate-sensitive old carbon reservoirs that have the potential to emit large quantities of methane, a potent greenhouse gas, as Earth continues warm. We present ice core isotopic measurements (Δ14C, δ13C, δD) from last deglaciation, which is partial analog for modern warming. Our results show emissions in response deglacial warming were small (<19 teragrams per year, 95% confidence interval) argue against similar future also indicate biomass...
Pulses of the past Bursts carbon dioxide, released into atmosphere and occurring on centennial time scales, were seen during cold periods last glacial cycle but not in older or warmer conditions. Nehrbass-Ahles et al. present a record atmospheric dioxide concentrations retrieved from European Project for Ice Coring Antarctica Dome C ice core showing that these jumps occurred both warm between 330,000 450,000 years ago. They relate pulses to disruptions Atlantic meridional overturning...
Abstract The ocean's immense ability to store and release heat on centennial millennial time scales modulates the impacts of climate perturbations. To gain a better understanding past variations in mean ocean temperature (MOT), noble gas‐based proxy measured from ancient air ice cores has been developed. Here we assess non‐temperature effects that may influence atmospheric gas ratios reconstructed polar how they impact signal with an intermediate complexity Earth system model. We find...
Significance Polar ice is a unique archive of past atmosphere. Here, we present methane stable isotope records (used as source fingerprint) for the current and two interglacials their preceding glacial maxima. Our data are used to constrain global emissions methane. Tropical wetlands floodplains seem be dominant sources atmospheric changes, steered by variations in sea level, monsoon intensity, temperature, water table. In contrast, geologic over wide range climatic conditions. The long-term...
Changes in temperature and carbon dioxide during glacial cycles recorded Antarctic ice cores are tightly coupled. However, this relationship does not hold for interglacials. While climate cooled towards the end of both last (Eemian) present (Holocene) interglacials, CO2 remained stable Eemian while rising Holocene. We identify review twelve biogeochemical mechanisms terrestrial (vegetation dynamics fertilization, land use, wildfire, accumulation peat, changes permafrost carbon, subaerial...
view Abstract Citations (114) References (81) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Coronae of Low-Mass Dwarf Stars Giampapa, M. S. ; Rosner, R. Kashyap, V. Fleming, T. A. Schmitt, J. H. Bookbinder, We report the results our analysis pointed X-ray observations nearby dMe and dM stars using position sensitive proportional counter (PSPC) on board ROSA T satellite (Roentgensatellit). In cases those M dwarf where PSPC pulse-height distributions...