New research from Columbia climate scientists shows that the 1987 ozone treaty, designed to protect the ozone layer, has postponed the occurrence of the first ice-free Arctic by as much as 15 years.

Using one of the most advanced atmospheric computer models available, scientists compared our expected future with a scenario in which ozone-depleting substances had never been regulated.

Scott Barrett, the Lenfest-Earth Institute Professor of Natural Resource Economics and an expert in complex international negotiations, teaches game theory in his Global Collective Action class. Using a simple card game, Barrett helps his students understand the consequences of decision making in complex negotiations, like those involved in climate treaties, where each country’s actions depend on the actions of others.

The greenhouse effect is not all about carbon dioxide. Several other substances, such as water vapor and methane, also play a key part in trapping radiation. Recently, a family of relatively obscure chemicals called hydrofluorocarbons, or HFCs, has entered the spotlight due to its role in global warming. HFCs are highly potent greenhouse warmers –… read more