These transparency and accountability provisions are similar to those in other international agreements. While the system does not include financial sanctions, the requirements are intended to easily track each nation`s progress and foster a sense of global peer pressure, which discourages any hesitation between countries that might consider doing so. Carbon dioxide, nitrous oxide and methane are gases that accumulate in the atmosphere and prevent heat from radiating from the Earth`s surface into space, resulting in a greenhouse effect. According to the Intergovernmental Panel on Climate Change (IPCC), the main international scientific panel working on this issue, the concentration of these heat-trapping gases has increased significantly since pre-industrial times and has reached levels not seen in at least 800,000 years. Carbon dioxide (the main cause of climate change) has increased by 40%, nitrous oxide by 20% and methane by 150% since 1750 – mainly from the combustion of dirty fossil fuels. The IPCC says it is „extremely likely“ that these emissions are mainly responsible for the rise in global temperatures since the 1950s. At the same time, deforestation and forest degradation have also contributed to their fair share of global carbon emissions. A preliminary study with inventory implications was published in April 2020 in Nature Communications. Based on a public policy database and multi-model scenario analysis, the authors showed that the implementation of current policies by 2030 leaves a median emissions gap of 22.4 to 28.2 GtCO2eq with the optimal pathways to implement the Paris targets well below 2°C and 1.5°C. If nationally determined contributions were fully implemented, this gap would be reduced by one third.
The countries assessed have not reached the promised contributions with implemented measures (implementation gap) or have an ambition gap with optimal trajectories towards trajectories well below 2°C. The study showed that all countries need to accelerate the implementation of renewable technology policies, while efficiency gains are particularly important in emerging economies and fossil fuel-dependent countries.  The long-term temperature objective of the Paris Agreement is to keep global average temperature rise well below 2°C (3.6°F) above pre-industrial levels. and continue efforts to limit the increase to 1.5°C (2.7°F), which would significantly reduce the risks and impacts of climate change. This should be done by reducing emissions as soon as possible in order to „achieve a balance between anthropogenic emissions from sources and removals of greenhouse gases by sinks“ in the second half of the 21st century. It also aims to increase the parties` ability to adapt to the adverse effects of climate change and to „balance financial flows with a trajectory towards low greenhouse gas emissions and climate-resilient development“. The countries most affected by the effects of climate change will be low-lying countries that are particularly vulnerable to sea-level rise and developing countries that do not have the resources to adapt to changes in temperature and precipitation. .