Keeping global warming below the threshold of 1.5 degrees is still ‘technically feasible.’ But we need to talk less and act more. Currently, countries are not honoring their national climate commitments. At this rate, we are heading towards an increase of 3.1°C. Even if we strictly adhere to the climate promises with a 2030 horizon, we would still reach +2.6-2.8°C. To meet the more ambitious target of the Paris Agreement, greenhouse gas emissions must be cut by 42% from 2019 levels by 2030. The potential exists: with current technologies and adequate investments, we can achieve a reduction of 52%. So far, genuine political and financial will has been lacking.
These are the key messages of the Emissions Gap Report 2024, the annual report produced by the UN Environment Agency (UNEP) and one of the most reliable tools for understanding whether the Paris goals are still within reach and what is needed to achieve them.
Emission Gap: What It Means and Why It’s Important
The emissions gap shows how far countries’ mitigation commitments are from the levels that science indicates are necessary to meet the Paris Agreement.
The emissions gap is the difference between:
- the estimated global greenhouse gas emissions resulting from the full implementation of the latest NDCs (the voluntary national plans that each country submits to the UN), and
- the global emissions identified in emission scenarios aligned with the long-term temperature goal (2100) of the Paris Agreement.
The Emissions Gap Report 2024 indicates the gap for 2030 and 2050 and the gap for 2035. This data is essential for assessing alignment with climate targets in the upcoming update of the NDCs. All countries are required to submit new national plans to the UN by February 2025, which must have a 2035 horizon. The current NDCs, however, have a 2030 horizon.
The Emissions Gap is “Huge,” According to the Emissions Gap Report 2024
To navigate the 100 dense pages of the Emissions Gap Report 2024, we can start with some numbers. Greenhouse gas emissions in 2023 reached 57.1 billion tons of CO2 equivalent (GtCO2eq). Instead of reducing them, we are increasing emissions: a rise of 1.3% compared to 2022. Moreover, we are increasing them more rapidly than we did in the last decade, when the average annual increase was 0.8%. In summary: not only are we heading in the wrong direction, but we are also accelerating.
What is the trajectory compatible with the goal of 1.5°C of global warming? By 2030, we should cut emissions by 42% from 2019 levels, and then increase that to a 57% reduction by 2035.
Quantifying the Emissions Gap
Let’s translate these data and percentages into absolute values and include them in the three scenarios analyzed in the UNEP report. How much emissions can we still produce in 2030, 2035, and 2050?
The three scenarios employed by the Emissions Gap Report lead to:
- Scenario 1: Stay around 1.5°C, with a limited or no temporary overshoot, and a 50% probability;
- Scenario 2: Stay below 1.8°C with a 66% probability;
- Scenario 3: Stay below 2°C with a 66% probability.
The emissions we can generate in the three key dates amount to:
- Scenario 1: 33 GtCO2eq in 2030, 25 in 2035, 8 in 2050. This would provide a 66% probability of peaking global warming around 1.6 or 1.7°C and dropping to 1.2-1.5°C by 2100.
- Scenario 2: 35 GtCO2eq in 2030, 27 in 2035, 12 in 2050. This would give a 66% chance of peaking at 1.6-1.8°C and reaching 1.4-1.7°C of global warming by 2100. Thus, there is still a residual possibility of staying below 1.5 degrees.
- Scenario 3: 41 GtCO2eq in 2030, 36 in 2035, 20 in 2050. This scenario would yield a 66% probability of reaching a peak of 1.8-1.9°C and finishing the century with 1.6-1.9°C. In this scenario, there is a 90% probability of rising to 2-2.4°C by the end of the century, failing even to meet the less ambitious target of the Paris Agreement. To stay within this scenario, emissions must be reduced by 28% by 2030 and 37% from 2019 levels by 2035.
What Happens If We Don’t Implement the Voluntary National Plans (NDCs)?
Another crucial data provided by the UNEP report is the projection of global warming based on the degree of implementation of the NDCs. Considering only current policies—meaning existing legislation excluding promises and goals—we are heading towards a temperature increase of 3.1 degrees.
The situation improves but is still dramatically insufficient when considering the contributions of the current NDCs:
- If by 2030 the NDCs were implemented literally, including both unconditional and conditional commitments (where countries commit on the condition of receiving certain funding or facilitation), we would be looking at a world 2.6 degrees warmer.
- Implementing only unconditional commitments leads to a rise of +2.8°C.
- Implementing all NDCs and meeting commitments to achieve net-zero emissions would result in +1.9°C, but these commitments are mostly vague, and their feasibility is currently unlikely.
All these scenarios would have “debilitating effects on people, the planet, and economies,” explains UNEP. None of them would stop global warming. The Earth’s temperature in 2100 would not stabilize but would continue to rise.
The Available Mitigation Potential in 2024
A third crucial piece of information for understanding the future trajectory of emissions and the importance of acting now to cut them is the consequences of delayed climate action. Every year of delay compared to the timelines outlined by the Emissions Gap Report 2024 necessitates accelerating action in the following year. Cuts not made are added to the account of the following year.
Less mitigation, more “locked-in” emissions, and less time available to implement technologies and solutions are the factors that erode the technically available potential—and they do so rapidly. For example, in this report, the mitigation potential is 7 GtCO2eq lower than that estimated in the last IPCC report, published only in 2022.
Since greenhouse gas emissions reached a new high of 57.1 gigatons of carbon dioxide equivalent in 2023, the cuts required from now on are greater: to limit warming to 1.5°C, emissions must be reduced by 7.5% annually until 2035. To stay below 2°C, the annual reduction must be 4%.
To date, the report calculates that the mitigation potential by 2030 amounts to 31 GtCO2eq, enough to still hope to remain on a trajectory compatible with 1.5°C. By 2035, the potential rises to 41 GtCO2eq. In both cases, the energy sector plays the largest role, with 12-15 GtCO2eq of potential. “This would close the gap to 1.5°C in both years, at a cost of less than $200 per ton of CO2 equivalent,” emphasizes UNEP.
This potential demonstrates that it is possible to achieve the targets set at COP28: tripling renewable energy capacity by 2030, doubling the annual global average rate of energy efficiency improvements by 2030, phasing out fossil fuels, and conserving, protecting, and restoring nature and ecosystems.
However, it will require “an unprecedented international mobilization,” says the report. At least six times more investment in mitigation, which is only possible with a reform of the global financial architecture. Most importantly, immediate and drastic action will be needed from G20 countries. Today, they account for 77% of global emissions. But they are also off track in meeting current NDCs.
Download the UNEP Emissions Gap Report (Emissions Gap Report 2024)