Nations must collectively commit to cutting 42 per cent off annual greenhouse gas emissions by 2030 and 57 per cent by 2035 in the next round of Nationally Determined Contributions (NDCs) – and back this up with rapid action – or the Paris Agreement’s 1.5°C goal will be gone within a few years, according to a new UN Environment Programme (UNEP) report.

Updated NDCs are to be submitted early next year ahead of the COP30 climate talks in Brazil. UNEP’s “Emissions Gap Report 2024: No more hot air … please!” finds that a failure to increase ambition in these new NDCs and start delivering immediately would put the world on course for a temperature increase of 2.6-3.1°C over the course of this century. This would bring debilitating impacts to people, planet and economies.

The 2.6°C scenario is based on the full implementation of current unconditional and conditional NDCs. Implementing only current unconditional NDCs would lead to 2.8°C of warming. Continuing with current policies only would lead to 3.1°C of warming. Under these scenarios – which all operate on a probability of over 66 per cent – temperatures would continue to rise into the next century. Adding additional net-zero pledges to full implementation of unconditional and conditional NDCs could limit global warming to 1.9°C, but there is currently low confidence in the implementation of these net-zero pledges.

“The emissions gap is not an abstract notion,” said António Guterres, UN Secretary-General, in a video message on the report. “There is a direct link between increasing emissions and increasingly frequent and intense climate disasters. Around the world, people are paying a terrible price. Record emissions mean record sea temperatures supercharging monster hurricanes; record heat is turning forests into tinder boxes and cities into saunas; record rains are resulting in biblical floods.

“Today’s Emissions Gap report is clear: we’re playing with fire; but there can be no more playing for time. We’re out of time. Closing the emissions gap means closing the ambition gap, the implementation gap, and the finance gap. Starting at COP29.”

The report also looks at what it would take to get on track to limiting global warming to below 2°C. For this pathway, emissions must fall 28 per cent by 2030 and 37 per cent from 2019 levels by 2035 – the new milestone year to be included in the next NDCs.

“Climate crunch time is here. We need global mobilisation on a scale and pace never seen before – starting right now, before the next round of climate pledges – or the 1.5°C goal will soon be dead and well below 2°C will take its place in the intensive care unit,” said Inger Andersen, Executive Director of UNEP. “I urge every nation: no more hot air, please. Use the upcoming COP29 talks in Baku, Azerbaijan, to increase action now, set the stage for stronger NDCs, and then go all-out to get on a 1.5°C pathway.

“Even if the world overshoots 1.5°C – and the chances of this happening are increasing every day – we must keep striving for a net-zero, sustainable and prosperous world. Every fraction of a degree avoided counts in terms of lives saved, economies protected, damages avoided, biodiversity conserved and the ability to rapidly bring down any temperature overshoot.”

The consequences of delayed action are also highlighted by the report. The cuts required are relative to 2019 levels, but greenhouse gas emissions have since grown to a record high of 57.1 gigatons of carbon dioxide equivalent in 2023. While this makes a marginal difference to the overall cuts required from 2019-2030, the delay in action means that 7.5 per cent must be shaved off emissions every year until 2035 for 1.5°C, and 4 per cent for 2°C. The size of the annual cuts required will increase with every year’s delay.

1.5°C still technically possible, but massive effort needed

The report shows that there is technical potential for emissions cuts in 2030 up to 31 gigatons of CO2 equivalent – which is around 52 per cent of emissions in 2023 – and 41 gigatons in 2035. This would bridge the gap to 1.5°C in both years, at a cost below US$200 per ton of CO2 equivalent.

Increased deployment of solar photovoltaic technologies and wind energy could deliver 27 per cent of the total reduction potential in 2030 and 38 per cent in 2035. Action on forests could deliver around 20 per cent of the potential in both years. Other strong options include efficiency measures, electrification and fuel switching in the buildings, transport and industry sectors.

This potential illustrates it is possible to meet the COP28 targets of tripling renewable energy capacity by 2030, doubling the global average annual rate of energy efficiency improvements by 2030, transitioning away from fossil fuels, and conserving, protecting and restoring nature and ecosystems.

However, delivering on even some of this potential will require unprecedented international mobilisation and a whole-of-government approach, focusing on measures that maximise socioeconomic and environmental co-benefits and minimise trade-offs.

A minimum six-fold increase in mitigation investment is needed for net-zero – backed by reform of the global financial architecture, strong private sector action and international cooperation. This is affordable: the estimated incremental investment for net-zero is US$0.9-2.1 trillion per year from 2021 to 2050 – investments that would bring returns in avoided costs from climate change, air pollution, damage to nature and human health impacts. For context, the global economy and financial markets are worth US$110 trillion per year.

The G20 members, responsible for the bulk of total emissions, must do the heavy lifting. However, this group is still off track to meet even current NDCs. The largest-emitting members will need to take the lead by dramatically increasing action and ambition now and in the new pledges.

G20 members, minus the African Union, accounted for 77 per cent of emissions in 2023. The addition of the African Union as a permanent G20 member, which more than doubles the number of countries represented from 44 to 99, brings the share up by only 5 per cent to 82 per cent – highlighting the need for differentiated responsibilities between nations. Stronger international support and enhanced climate finance will be essential to ensure that climate and development goals can be realized fairly across G20 members and globally.

Good NDC design crucial

The report also lays out how to ensure the updated NDCs are well-designed, specific and transparent so they can meet any new targets put in place. NDCs must include all gases listed in the Kyoto Protocol, cover all sectors, set specific targets, be explicit about conditional and unconditional elements and provide transparency around how the submission reflects a fair share of effort and the highest possible ambition.

They must also detail how national sustainable development goals can be achieved at the same time as efforts to reduce emissions, and include detailed implementation plans with mechanisms for review and accountability. For emerging market and developing economies, NDCs should include details on the international support and finance they need.

In a reaction to the development, Andreas Sieber, Associate Director of Policy and Campaigns, 350.org, says: “The emissions gap report is yet another clear warning about what needs to be done and fast. Last year at COP28, nations agreed to transition away from fossil fuels. The report makes it crystal clear that governments must translate this decision into action in their national climate pledges if they are serious about the just energy transition.

“When we talk about climate pledges, we are talking about more than just arbitrary, empty words. We’re talking about how plans to move away from dirty fossil fuels and transition to renewable energy fairly can create opportunities for communities around the world to thrive.”