The agreement between President Obama and Chinese President Xi Jinping on Saturday to wind down the production and consumption of a class of chemicals commonly used in refrigerators and air conditioners could mark a key step toward eliminating some of the most potent greenhouse gases.
The United States and roughly 100 other countries have already pledged to seek substitutes.
For the first time, the United States and China will work together to persuade other countries, most notably holdouts such as Brazil and India, to join the effort to slash or eliminate the use of hydrofluorocarbons, or HFCs.
The chemical group currently accounts for only 2 percent of greenhouse gases, but consumption is growing exponentially as people in developing countries grow wealthy enough to purchase air conditioners. A global push to get rid of HFCs could potentially reduce the greenhouse gases by the equivalent of 90 gigatons of carbon dioxide by 2050, equal to roughly two years’ worth of current global greenhouse gas emissions, experts estimate.