Major climatic events associated with a prolonged CO/sub 2/-induced warming

Technical Report · Thu Oct 01 04:00:00 EDT 1981

OSTI ID:5250316

Flohn, H

The climates of earlier geologic times may provide useful analogues for future climates that could follow global warming induced by CO/sub 2/. In particular, two climatic events are possible if CO/sub 2/ concentrations reach levels above 600 ppM, and if other greenhouse gases increase simultaneously, leading to an increase of 4 to 5/sup 0/C in global average temperature. One event, the disintegration of the West Antarctic ice sheet, last occurred about 120 thousand years ago. The other, the disappearance of the shallow drift ice in the Arctic Ocean, last occurred about 2.4 million years ago. Although this suggests that the West Antarctic ice is more fragile than the Arctic sea ice, the events may occur in the opposite order. Disappearance of the Arctic sea ice appears to require a shorter preparation time during and after the temperature rise, and hence may be anticipated first. The disappearance of the Arctic sea ice would constitute a case of unipolar glaciation. Paleoclimatic evidence suggests that the earth has experienced long periods of unipolar glaciation and that the effects of such radical asymmetry on global climate would be far-reaching. Chief among them would be shifts in the major climate zones, especially a northward displacement of the intertropical convergence zone and the subtropical anticyclones by 2/sup 0/ or more. This shift would produce seasonal temperature and precipitation patterns quite different from current ones, with significant drying and warming in the 35 to 45/sup 0/N latitude band. Such changes could have serious implications for human activities.

• Research Organization: Oak Ridge Associated Universities, Inc., TN (USA)
• DOE Contract Number: AC05-76OR00033
• OSTI ID: 5250316
• Report Number(s): ORAU/IEA-81-8(M); ON: DE82004909
• Country of Publication: United States
• Language: English

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Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION
AMBIENT TEMPERATURE
ASYMMETRY
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CLIMATES
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POLLUTION
TIME DEPENDENCE