The Paris agreement implies that greenhouse gas emissions need to be reduced significantly. To limit the temperature increase to 1.5 degrees, global CO2-emissions must reach net-zero around 2050. While in the past few years many countries have made net-zero pledges - a major step forward - the sum of these pledges is still insufficient to reach 1.5 degrees. Moreover, implemented policies are not yet ambitious and concrete enough to move towards the pledges, leaving a sizeable annual emissions gap of around 36 GtCO2-eq by 2050. This is a key conclusion of the ELEVATE Annual Net-Zero Report by PBL Netherlands Environmental Assessment Agency and research partners.
If all net-zero pledges materialize in effective policies, they bring the world closer to meeting the Paris climate goal of ‘well below 2 degrees, while pursuing efforts to limit the temperature increase to 1.5 degrees above pre-industrial levels’. Still, even when all net-zero pledges are fully lived up to, 1.5 degrees is still out of reach: an ambition gap of 6 GtCO2-eq still remains. When only accounting for all actually implemented policies, the world is projected to emit still an impressive annual 36 GtCO2-eq more in 2050 than the 1.5 degrees target allows for. This amounts to roughly two thirds of total current annual emissions of greenhouse gases.
Net-zero CO2 around 2050 required for 1.5 degrees
While global greenhouse gas emissions remain at an all-time high, global CO2 emissions must reach net-zero around 2050 to limit temperature increase to 1.5 degrees and around two decades later to stay well below 2 degrees. Since the COP26 in Glasgow in 2021, many countries have pledged to achieve net-zero emissions, mostly by the period 2040-2070, which is a hopeful development. Currently, all these net-zero pledges together cover 80 to 90 percent of global greenhouse gas emissions. The UNEP Emission Gap report looks at the emission gap by 2030 and 2035 based on the so-called Nationally Determined Contributions. The new ELEVATE Annual Net-Zero Report examines the outcomes of climate policies in 2050, when net-zero would actually need to be reached.
Net-zero pledges need to be clarified further
Many net-zero pledges lack important information on how they will be implemented. Therefore, it is unclear whether they will be met, leaving emission trajectories for the next decades uncertain. Some net-zero pledges do not even specify which greenhouse gases are included in it. This is problematic because the year in which net-zero emissions for CO2 alone need to be reached, is much earlier than for all greenhouse gases combined. Additionally, while 40 percent of countries have enshrined net-zero targets in policies or in law, over a third of the countries have no plan on how to realize their pledges. In most 1.5 and 2 degrees scenarios emissions peak between 2020 and 2025, followed by a sustained transition to net-zero. This means that if net-zero pledges are not implemented immediately , more negative emissions are needed later to reach a given target.
Most countries are not on track
The ELEVATE Annual Net-Zero Report captures the remaining emissions gaps for five major emitters: the EU, the US, China, India and Brazil. While the EU net-zero emission target has a clear structure, transparency, scope, analysis and a legal framework supporting the target, the EU could still miss its 2030 target of 55 percent emission reduction when the policies of individual member states are regarded. US policies for 2030 are well aligned with meeting its net-zero target by 2050, but the country lacks long term strategies. For China, India and Brazil, meeting their net-zero targets requires additional effort.
Open source online tool to explore national target
One of the major issues at the COP28 in Dubai is how much individual countries need to contribute to emission reductions: which share of the remaining global carbon budget can any country reasonably claim? What is a fair distribution? Commonly proposed principles concern fairness and equality (equal per capita allocation), responsibility (including historical emissions) and capability (which country is most capable in terms of wealth and institutions), while other commonly proposed principles are grand fathering (everyone reduces equal shares of their current emissions) and cost optimality (where do climate policies cost the least?). To show the outcomes of using different combinations of these equity principles for varying climate scenarios, PBL Environmental Assessment Agency and the Netherlands eScience Center have developed a free open source online tool: The Carbon Budget Explorer (beta version until December). The dashboard aims to create transparency and insight for policymakers, scientists and the generals public. Next year the ELEVATE Annual Net-Zero Report will focus specifically on justice and fairness.
In the ELEVATE project, climate policy research institutes from many countries in the world, including the USA, China, India, Brazil and Europe, collaborate to evaluate current international climate policy and suggest possible new policies to reach the goals of the Paris Climate Agreement. ELEVATE is funded by the European Horizon Europe programme.