Variations in the Earth's Orbit: Pacemaker of the Ice Ages

  title={Variations in the Earth's Orbit: Pacemaker of the Ice Ages},
  author={James D. Hays and John Z. Imbrie and Nicholas John Shackleton},
  pages={1121 - 1132}
1) Three indices of global climate have been monitored in the record of the past 450,000 years in Southern Hemisphere ocean-floor sediments. 2) Over the frequency range 10–4 to 10–5 cycle per year, climatic variance of these records is concentrated in three discrete spectral peaks at periods of 23,000, 42,000, and approximately 100,000 years. These peaks correspond to the dominant periods of the earth's solar orbit, and contain respectively about 10, 25, and 50 percent of the climatic variance… 
Stability of the Astronomical Frequencies Over the Earth's History for Paleoclimate Studies
Calculations suggest that the shortening of the Earth-moon distance and of the length of the day back in time induced a shortened of the fundamental periods for the obliquity and climatic precession over the last half-billion years.
Ice Sheets in Transition
  • P. Clark
  • Environmental Science
  • 2012
Elderfield et al. (4) provide important new insights into ice-age variability and the origin and timing of the middle Pleistocene transition, which began at some time after 1.25 million years ago.
Orbital variations, climate and paleoecology.
Model experiments on the 100,000-yr glacial cycle
It is believed that during the Quaternary era changes in global ice volume were mainly due to changes in the size of the ice sheets on the Eurasian and American continents. Time spectra of oxygen
Climate of the earth: an overview.
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    Environmental pollution
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Early onset and tropical forcing of 100,000-year Pleistocene glacial cycles
It is concluded that increased heat flow across the equator or from the tropics to higher latitudes around 1.5 Myr ago strengthened the semiprecession cycle in the Northern Hemisphere, and triggered the transition to sustained 100-kyr glacial cycles.
The timing of Pleistocene glaciations from a simple multiple-state climate model
The Earth's climate over the past million years has been characterized by a succession of cold and warm periods, known as glacial–interglacial cycles, with periodicities corresponding to those of the
Modeling the Climatic Response to Orbital Variations
This article summarizes how the theory has evolved since the pioneer studies of James Croll and Milutin Milankovitch, reviews recent evidence that supports the theory, and argues that a major opportunity is at hand to investigate the physical mechanisms by which the climate system responds to orbital forcing.


On the Precession as a Cause of Pleistocene Variations of the Atlantic Ocean Water Temperatures
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Insolation changes, ice volumes, and the O18 record in deep‐sea cores
A detailed curve of ice volume versus time is needed in order to test the validity of the hypothesis that changes in the earth's orbital parameters are the cause of oscillations in Pleistocene
Temperatures in the atmosphere, a t the earth's surface, and in the oceans have changed during geologic time following wide spectra of duration, amplitude, and areal extent. Without prejudice as to
Arithmetic of ice ages
THE Milankovitch hypothesis is that glaciations occur when the Northern Hemisphere receives relatively little summer heat from the Sun, because of astronomical factors that alter the orientation of
Variations in Magnetic Intensity and Climatic Changes
The correlation between variations of the magnetic intensity and evidence of climatic change from deep-sea sediment cores back to 1.2 m.y. has been extended to conclude that in the past 470,000 yr the magnetism of the Earth has modulated climate.
Milankovitch Hypothesis Supported by Precise Dating of Coral Reefs and Deep-Sea Sediments
Data show a parallelism over the last 150,000 years between changes in Earth's climate and changes in the summer insolation predicted from cycles in the tilt and precession of Earth's axis.
Atlantic Deep-Sea Stratigraphy: Extension of Absolute Chronology to 320,000 Years
Thorium-230 measurements on a core of globigerina ooze substantiate the prediction that the paleontological boundary U-V in the Atlantic sediments has an age of close to 320,000 years and confirms the assumption that sedimentation rates in the Caribbean Sea have not changed significantly during the past several hundred thousand years.