The Paris Agreement pushed signatories to reduce their carbon production and stop global warming below two degrees centigrade before the end of the century.
However, less than 18 months later, the United States, the The world's largest economy and the second largest carbon emitter, confirmed that it was withdrawing from the agreement.
How has the world responded?
Mark Lynas, a British author, journalist and environmental activist who focuses on climate change, says that Trump's decision has only served to "galvanize" the rest of the world.
He also left the stage clear for other leaders to shine on the subject.
French President Emmanuel Macron invited scientists, businessmen and NGO workers to move to his country shortly after Trump announced that the United States was moving away from the Paris text.
Cassie Flynn, global advisor on climate change in the UN Development Program, says that these developments show that "the momentum around the Paris Agreement certainly continues."
Many small and less developed nations of the world are also intensifying and Flynn adds, a fact emphasized by the Pacific island nation of Fiji presiding over COP 23.
Is the world on track to reduce emissions ?
The independent group of research organizations, which estimates the cuts that countries must make to avoid two degrees of warming, calculates a 3.2-degree jump before the end of the century when existing pledges are included.
Lynas says it has been "much more difficult to get away from fossil fuels than anyone thought", while the expansion of renewable energy has not happened as fast as expected.
This worries him about the difficulties to ensure the two degrees the goal is met even with the political will to do so.
Flynn, however, is more optimistic. She believes that Paris has provided the basic framework required for countries to work together. However, ambitions must be increased "as quickly as possible … (to) keep our emissions low and increase our resistance to climate change," he adds.
Why is leadership important in the absence of the United States?
Some believe that the withdrawal of EE. UU It could affect the way the Paris Pact develops.
Rob Bailey, director of research on energy, environment and resources in the UK The Chatham House expert group says that one of the main reasons for reaching a significant agreement in Paris was US and Chinese cooperation.
With the demise of America, Bailey questions whether China can be so ambitious without the dynamics created by another important partner like the United States.
Highlights the difficulties affecting other potential partners, such as the EU, which is politically concerned about Brexit and the refugee crisis.
Lynas, however, believes that China has indicated that it will "exploit its role as a leader" in this issue and "find support from most of the rest of the world" in if it does.
Substate Cities and Actors
Lynas says that cities in the United States are "keeping the flame alive" for the time being, while Flynn also highlights the work done in other major cities such as London and Paris, as they aim to reduce emissions.
Even with the main companies, cities and national states on board, however, the battle to achieve the ambitious objectives of the Paris Agreement is just beginning.