GLORIA

GEOMAR Library Ocean Research Information Access

X
You have 0 saved results.
Mark results and click the "Add To Watchlist" link in order to add them to this list.

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Material
Publisher
Person/Organisation
Language
Years
FID
Subjects(RVK)
  • 1
    Online Resource
    Online Resource
    East African megadroughts between 135 and 75 thousand years ago and bearing on early-modern human origins
    Proceedings of the National Academy of Sciences ; 2007
    In:  Proceedings of the National Academy of Sciences Vol. 104, No. 42 ( 2007-10-16), p. 16416-16421
    Details
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 104, No. 42 ( 2007-10-16), p. 16416-16421
    Abstract: The environmental backdrop to the evolution and spread of early Homo sapiens in East Africa is known mainly from isolated outcrops and distant marine sediment cores. Here we present results from new scientific drill cores from Lake Malawi, the first long and continuous, high-fidelity records of tropical climate change from the continent itself. Our record shows periods of severe aridity between 135 and 75 thousand years (kyr) ago, when the lake's water volume was reduced by at least 95%. Surprisingly, these intervals of pronounced tropical African aridity in the early late-Pleistocene were much more severe than the Last Glacial Maximum (LGM), the period previously recognized as one of the most arid of the Quaternary. From these cores and from records from Lakes Tanganyika (East Africa) and Bosumtwi (West Africa), we document a major rise in water levels and a shift to more humid conditions over much of tropical Africa after ≈70 kyr ago. This transition to wetter, more stable conditions coincides with diminished orbital eccentricity, and a reduction in precession-dominated climatic extremes. The observed climate mode switch to decreased environmental variability is consistent with terrestrial and marine records from in and around tropical Africa, but our records provide evidence for dramatically wetter conditions after 70 kyr ago. Such climate change may have stimulated the expansion and migrations of early modern human populations.
    Type of Medium: Online Resource
    ISSN: 0027-8424 , 1091-6490
    URL: Article
    DOI: 10.1073/pnas.0703874104
    RVK:
    TA 1000
    RVK:
    WA 15000
    Language: English
    Publisher: Proceedings of the National Academy of Sciences
    Publication Date: 2007
    detail.hit.zdb_id: 209104-5
    detail.hit.zdb_id: 1461794-8
    SSG: 11
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Paleoclimatic Evidence for Future Ice-Sheet Instability and Rapid Sea-Level Rise
    American Association for the Advancement of Science (AAAS) ; 2006
    In:  Science Vol. 311, No. 5768 ( 2006-03-24), p. 1747-1750
    Details
    In: Science, American Association for the Advancement of Science (AAAS), Vol. 311, No. 5768 ( 2006-03-24), p. 1747-1750
    Abstract: Sea-level rise from melting of polar ice sheets is one of the largest potential threats of future climate change. Polar warming by the year 2100 may reach levels similar to those of 130,000 to 127,000 years ago that were associated with sea levels several meters above modern levels; both the Greenland Ice Sheet and portions of the Antarctic Ice Sheet may be vulnerable. The record of past ice-sheet melting indicates that the rate of future melting and related sea-level rise could be faster than widely thought.
    Type of Medium: Online Resource
    ISSN: 0036-8075 , 1095-9203
    URL: Article
    DOI: 10.1126/science.1115159
    RVK:
    TA 1000
    RVK:
    WA 15000
    Language: English
    Publisher: American Association for the Advancement of Science (AAAS)
    Publication Date: 2006
    detail.hit.zdb_id: 128410-1
    detail.hit.zdb_id: 2066996-3
    detail.hit.zdb_id: 2060783-0
    SSG: 11
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Assessing the Risk of Persistent Drought Using Climate Model Simulations and Paleoclimate Data
    American Meteorological Society ; 2014
    In:  Journal of Climate Vol. 27, No. 20 ( 2014-10-15), p. 7529-7549
    Details
    In: Journal of Climate, American Meteorological Society, Vol. 27, No. 20 ( 2014-10-15), p. 7529-7549
    Abstract: Projected changes in global rainfall patterns will likely alter water supplies and ecosystems in semiarid regions during the coming century. Instrumental and paleoclimate data indicate that natural hydroclimate fluctuations tend to be more energetic at low (multidecadal to multicentury) than at high (interannual) frequencies. State-of-the-art global climate models do not capture this characteristic of hydroclimate variability, suggesting that the models underestimate the risk of future persistent droughts. Methods are developed here for assessing the risk of such events in the coming century using climate model projections as well as observational (paleoclimate) information. Where instrumental and paleoclimate data are reliable, these methods may provide a more complete view of prolonged drought risk. In the U.S. Southwest, for instance, state-of-the-art climate model projections suggest the risk of a decade-scale megadrought in the coming century is less than 50%; the analysis herein suggests that the risk is at least 80%, and may be higher than 90% in certain areas. The likelihood of longer-lived events ( & gt;35 yr) is between 20% and 50%, and the risk of an unprecedented 50-yr megadrought is nonnegligible under the most severe warming scenario (5%–10%). These findings are important to consider as adaptation and mitigation strategies are developed to cope with regional impacts of climate change, where population growth is high and multidecadal megadrought—worse than anything seen during the last 2000 years—would pose unprecedented challenges to water resources in the region.
    Type of Medium: Online Resource
    ISSN: 0894-8755 , 1520-0442
    URL: Article
    DOI: 10.1175/JCLI-D-12-00282.1
    RVK:
    UA 4548
    Language: English
    Publisher: American Meteorological Society
    Publication Date: 2014
    detail.hit.zdb_id: 246750-1
    detail.hit.zdb_id: 2021723-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Past and future global transformation of terrestrial ecosystems under climate change
    American Association for the Advancement of Science (AAAS) ; 2018
    In:  Science Vol. 361, No. 6405 ( 2018-08-31), p. 920-923
    Details
    In: Science, American Association for the Advancement of Science (AAAS), Vol. 361, No. 6405 ( 2018-08-31), p. 920-923
    Abstract: Impacts of global climate change on terrestrial ecosystems are imperfectly constrained by ecosystem models and direct observations. Pervasive ecosystem transformations occurred in response to warming and associated climatic changes during the last glacial-to-interglacial transition, which was comparable in magnitude to warming projected for the next century under high-emission scenarios. We reviewed 594 published paleoecological records to examine compositional and structural changes in terrestrial vegetation since the last glacial period and to project the magnitudes of ecosystem transformations under alternative future emission scenarios. Our results indicate that terrestrial ecosystems are highly sensitive to temperature change and suggest that, without major reductions in greenhouse gas emissions to the atmosphere, terrestrial ecosystems worldwide are at risk of major transformation, with accompanying disruption of ecosystem services and impacts on biodiversity.
    Type of Medium: Online Resource
    ISSN: 0036-8075 , 1095-9203
    URL: Article
    DOI: 10.1126/science.aan5360
    RVK:
    TA 1000
    RVK:
    WA 15000
    Language: English
    Publisher: American Association for the Advancement of Science (AAAS)
    Publication Date: 2018
    detail.hit.zdb_id: 128410-1
    detail.hit.zdb_id: 2066996-3
    detail.hit.zdb_id: 2060783-0
    SSG: 11
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Vegetation and environment in Eastern North America during the Last Glacial Maximum
    Elsevier BV ; 2000
    In:  Quaternary Science Reviews Vol. 19, No. 6 ( 2000-2), p. 489-508
    Details
    In: Quaternary Science Reviews, Elsevier BV, Vol. 19, No. 6 ( 2000-2), p. 489-508
    Type of Medium: Online Resource
    ISSN: 0277-3791
    URL: Article
    DOI: 10.1016/S0277-3791(99)00093-1
    RVK:
    RA 1000
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2000
    detail.hit.zdb_id: 780249-3
    detail.hit.zdb_id: 1495523-4
    SSG: 14
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Responses of plant populations and communities to environmental changes of the late Quaternary
    Cambridge University Press (CUP) ; 2000
    In:  Paleobiology Vol. 26, No. sp4 ( 2000-12), p. 194-220
    Details
    In: Paleobiology, Cambridge University Press (CUP), Vol. 26, No. sp4 ( 2000-12), p. 194-220
    Type of Medium: Online Resource
    ISSN: 0094-8373 , 1938-5331
    URL: Article
    DOI: 10.1666/0094-8373(2000)26[194:ROPPAC]2.0.CO;2
    Language: English
    Publisher: Cambridge University Press (CUP)
    Publication Date: 2000
    detail.hit.zdb_id: 2052186-8
    SSG: 12
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Responses of plant populations and communities to environmental changes of the late Quaternary
    Cambridge University Press (CUP) ; 2000
    In:  Paleobiology Vol. 26, No. S4 ( 2000), p. 194-220
    Details
    In: Paleobiology, Cambridge University Press (CUP), Vol. 26, No. S4 ( 2000), p. 194-220
    Abstract: The environmental and biotic history of the late Quaternary represents a critical junction between ecology, global change studies, and pre-Quaternary paleobiology. Late Quaternary records indicate the modes and mechanisms of environmental variation and biotic responses at timescales of 10 1 –10 4 years. Climatic changes of the late Quaternary have occurred continuously across a wide range of temporal scales, with the magnitude of change generally increasing with time span. Responses of terrestrial plant populations have ranged from tolerance in situ to moderate shifts in habitat to migration and/or extinction, depending on magnitudes and rates of environmental change. Species assemblages have been disaggregated and recombined, forming a changing array of vegetation patterns on the landscape. These patterns of change are characteristic of terrestrial plants and animals but may not be representative of all other life-forms or habitats. Complexity of response, particularly extent of species recombination, depends in part on the nature of the underlying environmental gradients and how they change through time. Environmental gradients in certain habitats may change in relatively simple fashion, allowing long-term persistence of species associations and spatial patterns. Consideration of late Quaternary climatic changes indicates that both the rate and magnitude of climatic changes anticipated for the coming century are unprecedented, presenting unique challenges to the biota of the planet.
    Type of Medium: Online Resource
    ISSN: 0094-8373 , 1938-5331
    URL: Article
    DOI: 10.1017/S0094837300026932
    Language: English
    Publisher: Cambridge University Press (CUP)
    Publication Date: 2000
    detail.hit.zdb_id: 2052186-8
    SSG: 12
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    The Continuum of Hydroclimate Variability in Western North America during the Last Millennium
    American Meteorological Society ; 2013
    In:  Journal of Climate Vol. 26, No. 16 ( 2013-08-15), p. 5863-5878
    Details
    In: Journal of Climate, American Meteorological Society, Vol. 26, No. 16 ( 2013-08-15), p. 5863-5878
    Abstract: The distribution of climatic variance across the frequency spectrum has substantial importance for anticipating how climate will evolve in the future. Here power spectra and power laws (β) are estimated from instrumental, proxy, and climate model data to characterize the hydroclimate continuum in western North America (WNA). The significance of the estimates of spectral densities and β are tested against the null hypothesis that they reflect solely the effects of local (nonclimate) sources of autocorrelation at the monthly time scale. Although tree-ring-based hydroclimate reconstructions are generally consistent with this null hypothesis, values of β calculated from long moisture-sensitive chronologies (as opposed to reconstructions) and other types of hydroclimate proxies exceed null expectations. Therefore it may be argued that there is more low-frequency variability in hydroclimate than monthly autocorrelation alone can generate. Coupled model results archived as part of phase 5 of the Coupled Model Intercomparison Project (CMIP5) are consistent with the null hypothesis and appear unable to generate variance in hydroclimate commensurate with paleoclimate records. Consequently, at decadal-to-multidecadal time scales there is more variability in instrumental and proxy data than in the models, suggesting that the risk of prolonged droughts under climate change may be underestimated by CMIP5 simulations of the future.
    Type of Medium: Online Resource
    ISSN: 0894-8755 , 1520-0442
    URL: Article
    DOI: 10.1175/JCLI-D-11-00732.1
    RVK:
    UA 4548
    Language: English
    Publisher: American Meteorological Society
    Publication Date: 2013
    detail.hit.zdb_id: 246750-1
    detail.hit.zdb_id: 2021723-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Recent Warming Reverses Long-Term Arctic Cooling
    American Association for the Advancement of Science (AAAS) ; 2009
    In:  Science Vol. 325, No. 5945 ( 2009-09-04), p. 1236-1239
    Details
    In: Science, American Association for the Advancement of Science (AAAS), Vol. 325, No. 5945 ( 2009-09-04), p. 1236-1239
    Abstract: The temperature history of the first millennium C.E. is sparsely documented, especially in the Arctic. We present a synthesis of decadally resolved proxy temperature records from poleward of 60°N covering the past 2000 years, which indicates that a pervasive cooling in progress 2000 years ago continued through the Middle Ages and into the Little Ice Age. A 2000-year transient climate simulation with the Community Climate System Model shows the same temperature sensitivity to changes in insolation as does our proxy reconstruction, supporting the inference that this long-term trend was caused by the steady orbitally driven reduction in summer insolation. The cooling trend was reversed during the 20th century, with four of the five warmest decades of our 2000-year-long reconstruction occurring between 1950 and 2000.
    Type of Medium: Online Resource
    ISSN: 0036-8075 , 1095-9203
    URL: Article
    DOI: 10.1126/science.1173983
    RVK:
    TA 1000
    RVK:
    WA 15000
    Language: English
    Publisher: American Association for the Advancement of Science (AAAS)
    Publication Date: 2009
    detail.hit.zdb_id: 128410-1
    detail.hit.zdb_id: 2066996-3
    detail.hit.zdb_id: 2060783-0
    SSG: 11
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    On the potential of Raman‐spectroscopy‐based carbonate mass spectrometry
    Wiley ; 2013
    In:  Journal of Raman Spectroscopy Vol. 44, No. 3 ( 2013-03), p. 469-474
    Details
    In: Journal of Raman Spectroscopy, Wiley, Vol. 44, No. 3 ( 2013-03), p. 469-474
    Abstract: The potential for using Raman spectroscopy to measure stable oxygen isotope ratios ( 18 O/ 16 O) in carbonates is evaluated by measuring the Raman spectra and isotope ratios of a suite of 60 synthesized, 18 O‐enriched calcite crystals ranging in composition from natural abundance (0.2 mole‐% 18 O) to 1.2 mole‐% 18 O. We determined the Raman‐inferred isotopic ratios (R Raman ) by fitting curves to the ν 1 symmetric stretching peak at 1086 cm −1 and the smaller satellite peak, associated with the ν 1 stretching mode of singly substituted carbonate groups (C 16 O 2 18 O) at 1065 cm −1 . The ratio of the two peak areas shows a 1:1 correspondence with the 18 O/ 16 O ratios derived from standard mass spectrometry methods, confirming that the relative intensities of the ν 1 symmetric stretching peaks is a direct measure of the isotopic ratio in the carbonates. The 1‐sigma uncertainties of the R Raman values of the individual crystals were 0.00079 (384‰ PDB) and 0.00043 (210‰ PDB) for the four‐crystal sample means. This level of uncertainty is much too high to provide significant estimates of natural variability; however, there are multiple prospects for improving the accuracy and precision of the technique. Carbon isotope ratios in carbonates cannot be measured by our approach, but our results highlight the potential of Raman‐based isotope ratio measurement for C and other elements in minerals and organic compounds. Copyright © 2012 John Wiley & Sons, Ltd.
    Type of Medium: Online Resource
    ISSN: 0377-0486 , 1097-4555
    URL: Issue
    URL: Article
    DOI: 10.1002/jrs.v44.3
    DOI: 10.1002/jrs.4218
    Language: English
    Publisher: Wiley
    Publication Date: 2013
    detail.hit.zdb_id: 1481008-6
    SSG: 11
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...