carbon dioxide
; fossil fuel
; Africa
; Asia
; astronomy
; climate change
; Little Ice Age
; Middle East
; Northern Hemisphere
; paleoclimate
; prediction
; priority journal
; review
; sea ice
; simulation
; Southern Hemisphere
; temperature
; Venezuela
; water cycle
; winter
; deglaciation
; global warming
; hydroclimate
; Intertropical Convergence Zone
; Carbon Dioxide
; Climate Change
; Fossil Fuels
; Models, Theoretical
; Oceans and Seas
英文摘要:
Major changes in global rainfall patterns accompanied a northward shift of Earth's thermal equator at the onset of an abrupt climate change 14.6 kya. This northward pull of Earth's wind and rain belts stemmed from disintegration of North Atlantic winter sea ice cover, which steepened the interhemispheric meridional temperature gradient. A southward migration of Earth's thermal equator may have accompanied the more recent Medieval Warm to Little Ice Age climate transition in the Northern Hemisphere. As fossil fuel CO2 warms the planet, the continents of the Northern Hemisphere are expected to warm faster than the Southern Hemisphere oceans. Therefore, we predict that a northward shift of Earth's thermal equator, initiated by an increased interhemispheric temperature contrast, may well produce hydrologic changes similar to those that occurred during past Northern Hemisphere warm periods. If so, the American West, the Middle East, and southern Amazonia will become drier, and monsoonal Asia, Venezuela, and equatorial Africa will become wetter. Additional paleoclimate data should be acquired and model simulations should be conducted to evaluate the reliability of this analog.
Broecker, W.S., Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, United States; Putnam, A.E., Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, United States, Climate Change Institute, University of Maine, Orono, ME 04469, United States
Recommended Citation:
Broecker W.S.,Putnam A.E.. Hydrologic impacts of past shifts of Earth's thermal equator offer insight into those to be produced by fossil fuel CO2[J]. Proceedings of the National Academy of Sciences of the United States of America,2013-01-01,110(42)