Just a few weeks ago, Secretary of State John Kerry admitted that "one of the most successful environmental agreements in history" was actually now a huge driver of climate change. Late last week, Kerry went further, saying that "HFCs [hydrofluorocarbons], which was supposed to be the solution, turned out not to be the solution," but can actually be "thousands of times more damaging than carbon dioxide."
Now, 170 countries, including the U.S., have agreed to cut the use of HFCs, used in many cooling and refrigeration system. The Montreal Protocol in 1987 phased out CFCs (chlorofluorocarbons) which were blamed for ozone depletion and causing the infamous "hole" in the ozone layer of the earth's atmosphere. Kerry credits the introduction of HFCs with saving the ozone layer, but acknowledges there were unintended consequences.
All of us here know that HFCs, which was supposed to be the solution, turned out not to be the solution. We replaced the ozone depleting substances, but we came to understand the hard way that HFCs may be safe for the ozone layer but they are disastrous for our climate, in many cases thousands of times more damaging than carbon dioxide.
When asked what assurances Secretary Kerry could offer that the Paris climate deal or the amendment(s) to the Montreal Protocol won't have similar unintended consequences, a State Department official responded: