The authors of the agreement have set a withdrawal period that President Trump must follow – which prevents him from irreparably harming our climate. The Paris Agreement is the first legally binding universal global agreement on climate change adopted at the Paris Climate Change Conference (COP21) in December 2015. Although the United States and Turkey are not parties to the agreement, as they have not indicated their intention to withdraw from the 1992 UNFCCC, they will continue to be required, as an “Annex 1” country under the UNFCCC, to end national communications and establish an annual inventory of greenhouse gases.  The implementation of the agreement by all the Member States combined will be evaluated every five years, with the first evaluation in 2023. The result will be used as an input for new national contributions from Member States.  The inventory will not be national contributions/achievements, but a collective analysis of what has been achieved and what remains to be done. In addition, countries are working to reach “the global peak in greenhouse gas emissions” as soon as possible. The agreement has been described as an incentive and engine for the sale of fossil fuels.   Negotiators of the agreement stated that the INDCs presented at the time of the Paris conference were insufficient. concerned that aggregate greenhouse gas emission estimates for 2025 and 2030, resulting from projected national contributions, are not covered by the most cost-effective scenarios at 2oC, but result in a forecast level of 55 gigatonnes.
By 2030, and acknowledging “that much greater efforts will be needed to reduce emissions in order to keep the increase in the average global temperature to less than 2 degrees Celsius by reducing emissions to 40 gigatonnes or 1.5 degrees Celsius.   [Clarification needed] States parties are subject to certain legally binding provisions, such as the requirement for developed countries to provide financial assistance to developing countries to enable them to implement the agreement. President Obama was able to formally enshrine the United States in the agreement through executive measures because he did not impose new legal obligations on the country. The United States already has a number of instruments on the books, under laws already passed by Congress to reduce carbon pollution. The country officially joined the agreement in September 2016, after submitting its request for participation. The Paris Agreement was only able to enter into force after the formal accession of at least 55 nations representing at least 55% of global emissions. This happened on October 5, 2016 and the agreement came into force 30 days later, on November 4, 2016. The agreement stated that it would only enter into force (and therefore fully effective) if 55 countries that produce at least 55% of global greenhouse gas emissions (according to a list drawn up in 2015)  ratify, accept, approve or adhere to the agreement.
  On April 1, 2016, the United States and China, which together account for nearly 40% of global emissions, issued a joint statement confirming that the two countries would sign the Paris climate agreement.  175 contracting parties (174 states and the European Union) signed the agreement on the first day of its signing.   On the same day, more than 20 countries announced plans to join the accession as soon as possible in 2016.