Technically, it is the 21st Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC), known among participants as COP 21. The UNFCCC was signed at the so-called Rio Earth Summit in 1992. In 1997, the Kyoto Protocol established legally binding obligations for developed countries to limit their greenhouse gas emissions. In 2010, the Cancun Agreements recognized that future global warming should be limited to below 2.0 degrees Celsius (3.6 degrees Fahrenheit) relative to pre-industrial levels.