Translations:Greenhouse gas emissions by the United States/17/en

Another area of concern is that of ozone-depleting substances such as chlorofluorocarbons (CFCs) and hydrofluorocarbons (HFCs), which are often potent greenhouse gases with serious global warming potential (GWP). However, significant progress has been made in reducing the usage of these gases as a result of the Montreal Protocol, the international treaty that took effect in 1989.