Learning about future climate from Earth's deep past - Jeffrey Kiehl (NCAR)





The interactive transcript could not be loaded.



Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Uploaded on Jan 13, 2011

Related news: http://www2.ucar.edu/news/3628/earth-...

The magnitude of climate change during Earth's deep past suggests that future temperatures may eventually rise far more than projected if society continues its pace of emitting greenhouse gases. NCAR scientist Jeffrey Kiehl says that carbon dioxide concentrations in the atmosphere may reach levels that last existed about 30 million to 100 million years ago, when global temperatures averaged about 29 degrees Fahrenheit (16 degrees Celsius) above pre-industrial levels. (more info)

Global temperatures may gradually rise over the next several centuries or millennia in response to the carbon dioxide. The elevated levels of the greenhouse gas may then remain in the atmosphere for tens of thousands of years.

Kiehl's study, which appeared as a "Perspectives" piece in the January 14, 2011 issue of the journal Science, also indicates that the planet's climate system, over long periods of times, may be at least twice as sensitive to carbon dioxide than currently projected by computer models, which have generally focused on shorter-term warming trends. This is largely because even sophisticated computer models have not yet been able to incorporate critical processes, such as the loss of ice sheets, that take place over centuries or millennia and amplify the initial warming effects of carbon dioxide.

All Comments

Comments are disabled for this video.
When autoplay is enabled, a suggested video will automatically play next.

Up next

to add this to Watch Later

Add to

Loading playlists...