Old Rocks
Diamond Member
ScienceDaily (Dec. 7, 2009) In the long term, the Earth's temperature may be 30-50% more sensitive to atmospheric carbon dioxide than has previously been estimated, reports a new study published in Nature Geoscience.
This would agree with what we are currently seeing. The climate response, particularly in the Arctic and Antarctic has been much more than predicted.
Earth More Sensitive to Carbon Dioxide Than Previously Thought - Global Warming and Nature - AOL Message Boards
The results show that components of the Earth's climate system that vary over long timescales -- such as land-ice and vegetation -- have an important effect on this temperature sensitivity, but these factors are often neglected in current climate models.
Dan Lunt, from the University of Bristol, and colleagues compared results from a global climate model to temperature reconstructions of the Earth's environment three million years ago when global temperatures and carbon dioxide concentrations were relatively high. The temperature reconstructions were derived using data from three million-year-old sediments on the ocean floor.
Lunt said, "We found that, given the concentrations of carbon dioxide prevailing three million years ago, the model originally predicted a significantly smaller temperature increase than that indicated by the reconstructions. This led us to review what was missing from the model."
This would agree with what we are currently seeing. The climate response, particularly in the Arctic and Antarctic has been much more than predicted.
Earth More Sensitive to Carbon Dioxide Than Previously Thought - Global Warming and Nature - AOL Message Boards
The results show that components of the Earth's climate system that vary over long timescales -- such as land-ice and vegetation -- have an important effect on this temperature sensitivity, but these factors are often neglected in current climate models.
Dan Lunt, from the University of Bristol, and colleagues compared results from a global climate model to temperature reconstructions of the Earth's environment three million years ago when global temperatures and carbon dioxide concentrations were relatively high. The temperature reconstructions were derived using data from three million-year-old sediments on the ocean floor.
Lunt said, "We found that, given the concentrations of carbon dioxide prevailing three million years ago, the model originally predicted a significantly smaller temperature increase than that indicated by the reconstructions. This led us to review what was missing from the model."
