A preliminary inventory-impact study was published in Nature Communications in April 2020. Based on a public policy database and a multi-model scenario analysis, the authors showed that the implementation of current strategies by 2030 leaves an average emission gap of 22.4 to 28.2 GtCO2eq, with optimal means to achieve targets well below 2 degrees Celsius and 1.5 degrees Celsius. If national contributions were fully implemented, this gap would be reduced by one-third. The countries assessed did not achieve their promised contributions with implemented measures (implementation deficit) or experienced a gap in ambition with optimal paths to well below 2oC. The study showed that all countries should accelerate the implementation of renewable technology strategies, while improving efficiency in emerging and fossil fuel-dependent countries is particularly important. [31] While the Paris Agreement ultimately aims to limit global temperature increase to 1.5 degrees Celsius this century, many studies evaluating the voluntary commitments of some countries in Paris show that the cumulative effect of these emission reductions will not be significant enough to keep temperatures below that ceiling. Indeed, the targets set by the target countries should limit the future increase in temperature between 2.7 and 3.7 degrees Celsius. At the same time, recent assessments of countries` developments in the framework of their climate targets in Paris indicate that some countries are already not meeting their commitments. 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) [65] ratify, accept, approve or adhere to the agreement.
[66] [67] 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. [69] 175 contracting parties (174 states and the European Union) signed the agreement on the first day of its signing. [59] [70] 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. Currently, 197 countries – every nation on earth, the last signatory is war-torn Syria – have adopted the Paris Agreement. 179 of them have consolidated their climate proposals with official approval, including, for the time being, the United States. The only major emitters that have yet to formally accede to the agreement are Russia, Turkey and Iran. Another key difference between the Paris Agreement and the Kyoto Protocol is its scope. While the Kyoto Protocol distinguishes between Schedule 1 countries and those not annexed to Schedule 1, this branch is scrambled in the Paris Agreement, as all parties must submit emission reduction plans. [34] While the Paris Agreement continues to emphasize the principle of “common but differentiated responsibility and respective capabilities” – the recognition that different nations have different capacities and duties to combat climate change – it does not offer a specific separation between developed and developing countries. [34] It therefore appears that negotiators will have to continue to address this issue in future rounds of negotiations, although the debate on differentiation could take on a new dynamic. [35] There are several opportunities to integrate flexibility mechanisms into the broader transparency framework.
