In the News Now: How UC Research Led to a Landmark Global Deal against Super Pollutants

An agreement among more than 170 countries to halt production of hydrofluorocarbons (HFCs) used in refrigerators and air conditioners has its origin in the work of a Scripps Institution of Oceanography at the University of California climate scientist.

Distinguished Professor of Climate and Atmospheric Sciences Veerabhadran Ramanathan's study of the greenhouse effect of chemical compounds used as refrigerants dates back to the early 1970s. Ramanathan's landmark 1975 paper that found that chlorofluorocarbons (CFCs) had a greenhouse effect 10,000 times that of the most ubiquitous climate change agent generated by human activities, carbon dioxide. The damage CFCs caused to Earth's protective ozone layer led to their phase-out and replacement by HFCs, which unfortunately also have a greenhouse warming effect in the atmosphere several thousands times greater than carbon dioxide.

Ramanathan estimated in studies released in 2010 and 2013 that ending the use of HFCs would reduce warming by 0.5 degrees C (roughly 1 degree F). The estimate was cited by U.S. Secretary of State John Kerry during negotiations last week in Kigali, Rwanda to amend the Montreal Protocol, the agreement that originally phased out CFC use.

This University of California article gives the backstory on the role of Ramanathan's research in the historic binding accord.

- Robert Monroe