Journal ArticleDOI
Past Temperatures Directly from the Greenland Ice Sheet
Dorthe Dahl-Jensen,Klaus Mosegaard,Niels S. Gundestrup,Gary D. Clow,Sigfus J Johnsen,A. W. Hansen,Niels Balling +6 more
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TLDR
A Monte Carlo inverse method has been used on the temperature profiles measured down through the Greenland Ice Core Project (GRIP) borehole, at the summit of the Greenland ice Sheet, and the Dye 3 borehole 865 kilometers farther south, resulting in a 50, 000-year-long temperature history at GRIP and a 7000-year history at Dye3.Abstract:
A Monte Carlo inverse method has been used on the temperature profiles measured down through the Greenland Ice Core Project (GRIP) borehole, at the summit of the Greenland Ice Sheet, and the Dye 3 borehole 865 kilometers farther south. The result is a 50, 000-year-long temperature history at GRIP and a 7000-year history at Dye 3. The Last Glacial Maximum, the Climatic Optimum, the Medieval Warmth, the Little Ice Age, and a warm period at 1930 A.D. are resolved from the GRIP reconstruction with the amplitudes -23 kelvin, +2.5 kelvin, +1 kelvin, -1 kelvin, and +0.5 kelvin, respectively. The Dye 3 temperature is similar to the GRIP history but has an amplitude 1.5 times larger, indicating higher climatic variability there. The calculated terrestrial heat flow density from the GRIP inversion is 51.3 milliwatts per square meter.read more
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Holocene sea-ice variations in Greenland: onshore evidence
TL;DR: The oldest dated driftwood log from northern Greenland is c. 9300 cal. years old, which is about 2000 years younger than the beginning of the last deglaciation as mentioned in this paper.
Journal ArticleDOI
Late Holocene variability in Florida Current surface density: Patterns and possible causes
David C Lund,William B Curry +1 more
TL;DR: In this paper, foraminiferal δ18O time series from three well-dated, high sedimentation rate cores near the Florida Keys (244°N, 833°W) exhibit repeated centennial to millennial-scale oscillations during the late Holocene Isotopic shifts of 02-03‰ over the past 5200 years represent changes in sea-surface temperature (SST) of 10-15°C or salinity variability of 1-2 psu.
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Coexisting with Large Carnivores: Lessons from Greater Yellowstone
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Modelling of late Quaternary climate over Asia: a synthesis
TL;DR: In this article, the authors present results from numerical simulations of the Last Glacial Maximum (LGM) and the mid-Holocene, and focus on the multiple processes that control regional climate of the Himalaya and surrounding areas, with emphasis on monsoon dynamics and variability.
Journal ArticleDOI
Climate change: detection and attribution of trends from long-term geologic data
TL;DR: The results suggest that 20th Century warming trends are plausibly a continuation of past climate patterns, and are not precise enough to solve the attribution problem by partitioning warming into natural versus human-induced components.
References
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Journal ArticleDOI
Decadal Trends in the North Atlantic Oscillation: Regional Temperatures and Precipitation
TL;DR: An evaluation of the atmospheric moisture budget reveals coherent large-scale changes since 1980 that are linked to recent dry conditions over southern Europe and the Mediterranean, whereas northern Europe and parts of Scandinavia have generally experienced wetter than normal conditions.
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Heat flow from the Earth's interior: Analysis of the global data set
TL;DR: In this paper, a new estimate of the Earth's heat loss based on a new global compilation of heat flow measurements comprising 24,774 observations at 20,201 sites is presented, which when areally weighted yield a global mean of 87 mW m -2 and a global heat loss of 44.2 x 10 2 W, an increase of some 4-8% over earlier estimates.
Journal ArticleDOI
Monte Carlo sampling of solutions to inverse problems
Klaus Mosegaard,Albert Tarantola +1 more
TL;DR: In inverse problems, obtaining a maximum likelihood model is usually not sucient, as the theory linking data with model parameters is nonlinear and the a posteriori probability in the model space may not be easy to describe.
Journal ArticleDOI
Arctic Environmental Change of the Last Four Centuries
Jonathan T. Overpeck,Konrad A Hughen,D. Hardy,Raymond S. Bradley,R. Case,M. A. Douglas,Bruce P. Finney,K. Gajewski,Gordon C. Jacoby,Anne E. Jennings,Scott F. Lamoureux,A. Lasca,Glen M. MacDonald,J.J. Moore,Michael Retelle,S. Smith,Alexander P. Wolfe,G. Zielinski +17 more
TL;DR: A compilation of paleoclimate records from lake sediments, trees, glaciers, and marine sediments provides a view of circum-Arctic environmental variability over the last 400 years.
Journal ArticleDOI
Climate instability during the last interglacial period recorded in the GRIP ice core
TL;DR: Isotope and chemical analyses of the GRIP ice core from Summit, central Greenland reveal that climate in Greenland during the last interglacial period was characterized by a series of severe cold periods, which began extremely rapidly and lasted from decades to centuries.