The idea was to create a dynamic structure that could develop along with changes in economies, technology and political will, said Christiana Figueres, who headed the UN office, which coordinated the Discussions that culminated in the Paris Agreement. This flexibility, she noted, has recently enabled a number of nations to strengthen their initial commitments by promising to reduce their net climate emissions to zero by 2050. The European Union, Canada, South Korea, Japan, South Africa and the United Kingdom have all made this promise. U.S. President-elect Joe Biden has supported that goal and promised to make the fight against climate change a centerpiece of his presidency. Meanwhile, China, the world`s largest source of emissions, has announced that it will reduce climate pollution faster than originally promised, with the goal of achieving carbon neutrality by 2060. In an effort to “significantly reduce the risks and effects of climate change,” the agreement calls for the average increase in global temperature over this century to be well below 2 degrees Celsius, while continuing efforts to limit temperature rise to 1.5 degrees. It also calls on countries to commit as quickly as possible to comparing global greenhouse gas emissions and to become carbon neutral by the second half of this century. To achieve these goals, 186 countries – responsible for more than 90% of global emissions – presented CO2 reduction targets prior to the Paris conference, known as “determined national contributions” (INDC). These targets set out the commitments made by each country to reduce emissions until 2025 or 2030, including macroeconomic targets for co2 reduction and individual commitments of some 2,250 cities and 2,025 companies. Although this has been going on for a long time, there is still a sense of disappointment for many Americans who believe that climate change is the greatest global challenge and that the United States should oppose it. The change is the result of a combination of technological, economic and political change, says Bill Hare, physicist and CEO of Climate Analytics, a non-profit organization that is part of the consortium.