Do Carbon Emissions Cause Global Warming?

According to a new study in Nature Geoscience , we still don’t know:

No one knows exactly how much Earth’s climate will warm due to carbon emissions, but a new study suggests scientists’ best predictions about global warming might be incorrect.

The study, which appears in Nature Geoscience , found that climate models explain only about half of the heating that occurred during a well-documented period of rapid global warming in Earth’s ancient past. The study, which was published online July 13, contains an analysis of published records from a period of rapid climatic warming about 55 million years ago known as the Palaeocene-Eocene thermal maximum, or PETM.

“In a nutshell, theoretical models cannot explain what we observe in the geological record,” said oceanographer Gerald Dickens, a co-author of the study and professor of Earth science at Rice University. “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.”