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. The ratification by the European Union has achieved a sufficient number of contracting parties to enter into force on 4 November 2016. These rules of transparency and accountability are similar to those set out in other international agreements. Although the system does not include financial sanctions, the requirements are intended to easily monitor the progress of individual nations and promote a sense of overall group pressure, discouraging any towing of feet among countries that might consider it. COP 21 or the Paris Climate Conference have resulted in a new international climate agreement that applies to all countries and aims to keep global warming below 2 degrees Celsius, in line with the recommendations of the Intergovernmental Panel on Climate Change (IPCC). Unlike the Kyoto Protocol, which set legally binding emission reduction targets (as well as penalties for non-compliance) only for industrialized countries, the Paris Agreement requires all countries – rich, poor, developed and developing – to take their share and reduce their greenhouse gas emissions.
To this end, the Paris Agreement provides for greater flexibility: commitments that countries should make are not included, countries can voluntarily set their emissions targets and countries will not be penalized if they do not meet their proposed targets. But what the Paris agreement requires is to monitor, report and reassess, over time, the objectives of individual and collective countries, in order to bring the world closer to the broader objectives of the agreement. And the agreement stipulates that countries must announce their next round of targets every five years, contrary to the Kyoto Protocol, which was aimed at this target but which contained no specific requirements to achieve this goal. The Paris Agreement is the world`s first comprehensive climate agreement.  Under the Paris Agreement, each country must define, plan and report regularly on its contribution to warming mitigation.  There is no mechanism for a country to set an emission target for a specified date, but any target should go beyond the previous targets. The United States formally withdrew from the agreement the day after the 2020 presidential election, although President-elect Joe Biden said America would return to the agreement after his inauguration.  Negotiators of the agreement stated that the INDCs presented at the time of the Paris conference were insufficient and found that “the estimates of aggregate greenhouse gas emissions in 2025 and 2030, resulting from planned contributions at the national level, do not fall into scenarios at 2oC at the lowest cost, but lead to a projected level of 55 gigatonnes in 2030.” and recognizes that “much greater efforts to reduce emissions will be required to keep the increase in the global average temperature below 2 degrees Celsius, by reducing emissions to 40 gigatonnes or 1.5 degrees Celsius.”  [Clarification needed] Although mitigation and adjustment require increased climate funding, adjustment has generally received less support and mobilized less private sector action.  A 2014 OECD report showed that in 2014, only 16% of the world`s financial resources were devoted to adaptation to climate change.  The Paris Agreement called for a balance between climate finance between adaptation and mitigation, stressing in particular the need for support for adaptation from the parties most affected by the effects of the