The earth will warm about 2.4 degrees C (4.3 degrees F) above pre-industrial levels even under extremely conservative greenhouse-gas emission scenarios and under the assumption that efforts to clean up particulate pollution continue to be successful, according to a new analysis by a pair of researchers at Scripps Institution of Oceanography at UC San Diego.

That amount of warming falls within what the world's leading climate change authority recently set as the threshold range of temperature increase that would lead to widespread loss of biodiversity, deglaciation and other adverse consequences in nature.

The researchers, writing in the online edition of the Proceedings of the National Academy of Sciences, argue that coping with these circumstances will require "transformational research for guiding the path of future energy consumption."

"This paper demonstrates the major challenges society will have to face in dealing with a problem that now seems unavoidable," said the paper's lead author, Scripps Atmospheric and Climate Sciences Professor V. Ramanathan.