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Landmarks in the History of Science » Geoscience » Pleistocene Temperatures, 1955: The first validation of Milutin Milankovitch astronomical theory of climate change


Pleistocene Temperatures, 1955: The first validation of Milutin Milankovitch astronomical theory of climate change

Autor: Cesare Emiliani
Cod: 6376
In stoc: Da
220000.00Lei

Detalii produs 1st validation of Milankovitch astronomical theory of climate by 
means of oxygen isotope-ratio data.

This research also was a groundbreaking in paleoclimatology and 
represented the foundation of paleoceanography.

''By August 1955, Emiliani had analyzed eight deep-sea cores.
His conclusions were published in an article called ''Pleistocene
Temperatures'', which appeared in the Journal of Geology (1955).
The article proved to be a landmark in the study of the ice ages.
According to Emiliani, isotopic variations in cores taken from the
Caribbean and from the equatorial Atlantic indicated that over 
the last 300,000 years there had been seven complete glacial-
interglacial cycles. The data also seemed to indicate that during  
a typical ice age, surface waters in the Caribbean dropped
approximately 6 degrees C. Finally, Emiliani noted that the
variations in isotopically estimated temperatures showed a 
reasonably good time correspondence with the Milankovitch
radiations curves, and concluded that his observations tended 
to support the astronomical theory of the ice ages.''

John Imbrie and Catherine Palmer Imbrie - Ice Ages: Solving
the Mystery, Macmillan, London, 1979, pp. 136-137

"His most infuential paper, ''Pleistocene Temperatures'' was
published in 1955 (Emiliani, 1955). The paper presented for the
first time (1) variations in the composition of oxygen isotope
ratios in carbonate tests of marine planktonic foraminifera, (2)
temperatures changes of ocean surface water during the late
Pleistocene, (3) an oscillation of warm and cold stages, that is, the
oxygen isotope stratigraphy, (4) ocean temperatures fluctuations
in relations to glaciations on the continents, and (5) the application
of Milutin Milankovitch's orbital theory to calculate the ages of the
ice ages.

This five approaches are today the foundations of marine and
terrestrial paleoclimatic research. The absolute ages assigned by
Emiliani to the warm and cold stages have changed, but
''Pleistocene Temperatures'' was extremely influential in
establishing the oscillating nature of past climate variations.
Emiliani was one of the first to apply a new technique (oxygene
isotope ratios), based on physical fundamentals, to quantify past
ocean property. He crossed the border between nuclear physics
and geology, applied the latest technical innovations to high-quality
samples, and provided a grand vision for the interpretation of his
results. He spent his entire scientific life on the further validation
and improvement of this concept, supporting it with sound scientific
papers and initiating large programs such as the Deep-Sea Drilling
Project.''

Encyclopedia of Global Change, Andrew S. Goudi and David J. Cuff
(Editors), Oxford University Press, 2001, Vol. 1, p. 346

''He [Cesare Emiliani] worked to introduce calendar reform, in part to
eliminate the BC-AD chronology hiatus caused by the lack of a zero
year, but more importantly to eliminate the use of religion-based
systems in a multicultural context.''

College of Science and Art - University of Miami


The last words of this magnifique paper are scientific prophecies
about earth's future climate:
''A glimpse of future climate might be obtained by extending the 
insolation curve toward the future; if its trend during the last 10,000
years (fig. 14) continues, an insolation minimum may be expected to
occur in about 10,000 years, when the northern lands will have
completed their isostatic recovery. Conditions will then be for the
inception of a new ice age."


''Pleistocene Temperatures'' in: The Journal of Geology, Vol. 63, No. 6
November 1955, pp. 538-578, The University of Chicago Press, Chicago
1st edition, printed wrappers, minor previous owner marks, good
condition.

Price: $ 50,000.00