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. Every five years, countries should assess their progress in implementing the agreement in a process known as a global balance sheet; the first is scheduled for 2023. Countries set their own targets and there is no implementation mechanism to ensure that they achieve these goals. In July 2020, the World Meteorological Organization (WMO) announced that it would estimate a 20% probability of global warming relative to pre-industrial values of more than 1.5 degrees Celsius in at least one year between 2020 and 2024, with 1.5 degrees Celsius as a key threshold under the Paris Agreement.   The consequences will be much worse when the 2oC threshold is reached, say the scientists. “We`re heading for a disaster if we can`t fail our warming and we have to do it very quickly,” says Alice C. Hill, CFR Senior Fellow for Energy and the Environment.
Gupta et al. (2007) evaluated the literature on climate policy. They found that no relevant evaluation of the UNFCCC or its protocol has stated that these agreements will solve the climate problem or be successful.  In these evaluations, it was considered that the UNFCCC or its protocol would not be changed. The Framework Convention and its protocol contain provisions for future policy measures to be taken. The 32-part document sets out a framework for global action on climate change, including climate change mitigation and adaptation, support for developing countries and transparency of reporting, and strengthening climate change goals. Here`s what to do: according to the United Nations Environment Programme (UNEP), if only the current climate commitments of the Paris Agreement are abandoned, temperatures are likely to have risen by 3.2 degrees Celsius by the end of the 21st century.