Aeronomy and Paleoclimate

  1. A. Berger,
  2. R. E. Dickinson and
  3. John W. Kidson
  1. J.-C. Gérard

Published Online: 18 MAR 2013

DOI: 10.1029/GM052p0139

Understanding Climate Change

Understanding Climate Change

How to Cite

Gérard, J.-C. (1989) Aeronomy and Paleoclimate, in Understanding Climate Change (eds A. Berger, R. E. Dickinson and J. W. Kidson), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM052p0139

Author Information

  1. Institut d'Astrophysique, Université de Liège, B-4200 Ougrée-Liège, Belgium

Publication History

  1. Published Online: 18 MAR 2013
  2. Published Print: 1 JAN 1989

ISBN Information

Print ISBN: 9780875904573

Online ISBN: 9781118666517

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Keywords:

  • Climate changes—Congresses

Summary

Solar-Terrestrial and aeronomic interactions with the Earth's global climate played a key role throughout the evolution of the planet. The evolving composition of the terrestrial atmosphere due to geochemical and biospheric interactions strongly controlled the paleoclimate. An example is the apparent absence of glaciation in a period when the solar luminosity was substantially smaller than at the present time (young sun luminosity paradox). The most convincing explanation proposed so far assumes the existence of larger amounts of infrared radiatively active gases (CO2, CH4) in the ancient atmosphere.

The vertical thermal structure of the atmosphere was notably different from the contemporary one, due to the lower abundance of oxygen and ozone before the development of green-plant photosynthesis. For O2 mixing ratios less 10−4 time the present atmospheric level, the presence of 11-year and longer periodicities has been observed in precambrian and more recent varve formations. It has been interpreted as an indication of a stronger response of the ancient atmosphere to solar cycle activity. This increased sensitivity was possibly the consequence of a lower O2 atmospheric mixing ratio and a less developed stratosphere.