Emissions didn't spike in 2025. That doesn't mean climate crisis has been stopped in its tracks

Global emissions flattened in 2025, but the UN says deeper cuts are needed to limit warming and return to 1.5°C by 2100.

Global greenhouse gas emissions flattened out in 2025, with a slight estimated decline from the previous year, but this is not enough to establish that emissions have peaked. The world remains on track for 2.8°C of warming this century if current climate policies continue, according to a United Nations report published on October 21, 2026.

UNEP estimates that continued implementation of current policies could lead to global temperatures reaching 2.8°C above pre-industrial levels this century, with warming increasing thereafter. (Pexels/ Representational)

The United Nations Environment Programme’s (UNEP) Emissions Gap Report 2026: The Point of Return estimates that global greenhouse gas emissions totalled 58.4 billion tonnes of carbon dioxide equivalent (GtCO₂e) in 2025, around 0.16 GtCO₂e lower than in 2024. The report cautions that the figures carry considerable uncertainty, and the available estimates do not establish the overall direction of emissions.

The findings highlight the gap between the current pace of climate action and the cuts needed to limit global warming. UNEP says the world has lost the opportunity to keep warming to 1.5°C above pre-industrial levels without, or with only limited, overshoot. However, steep emissions reductions could still limit how far temperatures rise above that threshold and help bring them back to 1.5°C by the end of the century.

Have global emissions peaked?

The near-flat emissions estimate for 2025 does not necessarily signal a lasting reversal in the global trend.

According to the report, the slight decline in total emissions was driven partly by lower emissions from land use, land-use change and forestry. This was associated in part with a decline in wildfire emissions, which offset a small increase in emissions from fossil fuels and other greenhouse gases.

Emissions from fossil fuels increased slightly between 2024 and 2025, even as the overall figure remained broadly stable. The data therefore do not establish that the world has reached a sustained peak in greenhouse gas emissions.

The distinction matters because emissions need to decline substantially, rather than merely stop growing, to limit further warming.

UNEP estimates that continued implementation of current policies could lead to global temperatures reaching 2.8°C above pre-industrial levels this century, with warming increasing thereafter. If countries fully implement their existing climate pledges and sustain similar efforts, warming could be limited to 2.6°C.

Even in the most optimistic scenario assessed by UNEP, which combines the full implementation of national commitments with additional net-zero targets, global warming would reach around 2.1°C this century.

These projections show the gap between the emissions reductions countries have promised and the scale of action needed to meet the Paris Agreement’s temperature goals.

Why is the 1.5°C target slipping out of reach?

The Paris Agreement, adopted in 2015, commits countries to holding the increase in global average temperature to well below 2°C above pre-industrial levels while pursuing efforts to limit it to 1.5°C.

UNEP’s latest report says keeping warming below 1.5°C without significant overshoot is no longer achievable. The focus has therefore shifted to limiting the overshoot and returning temperatures to the threshold by the end of the century.

The report’s “lowest possible” overshoot scenario would limit peak warming to around 1.7°C to 1.8°C by the middle of the century, before bringing global temperatures back to or below 1.5°C by 2100. This pathway has about a 50% chance of achieving that return, according to UNEP.

However, reaching it would require emissions to fall much faster than current commitments indicate.

UNEP Executive Director Inger Andersen said every additional fraction of a degree and every additional year of warming above 1.5°C increases climate risks, including those associated with floods, heatwaves and wildfires.

“The emissions gap is now a leadership gap. And the world is running out of time and excuses to close it,” UN Secretary-General António Guterres said in a message accompanying the report.

How much do emissions need to fall?

To reach the lowest-overshoot pathway, global greenhouse gas emissions would need to fall by:

- 18% by 2030

- 45% by 2035

- 69% by 2040

All reductions are measured against 2025 levels.

By comparison, the full implementation of countries’ Nationally Determined Contributions (NDCs) would reduce emissions by only 5% to 8% by 2030 and 11% to 15% by 2035, relative to 2025, the report says.

NDCs are national climate action plans submitted under the Paris Agreement. They outline countries’ commitments to reduce emissions and address climate change.

The scale of the required cuts means countries would need to strengthen their near-term targets and implement them much faster. UNEP estimates that emissions would have to decline at an average annual rate of 5.7% between 2025 and 2035 to get on the lowest-overshoot pathway.

The report also warns that every five years of carbon dioxide emissions at current levels pushes peak warming up by around 0.1°C.

What needs to change in energy and industry?

The report identifies faster deployment of renewable energy, improved energy efficiency and a shift away from fossil fuels as key priorities.

Since the Paris Agreement was adopted, global renewable electricity capacity has grown three times faster than anticipated, while solar photovoltaic capacity has expanded seven times faster. UNEP also says the total energy supply from coal and oil has grown more slowly than previously projected.

However, these changes have not been sufficient to bring emissions onto the required downward trajectory.

The report sets out sectoral benchmarks for extending climate action beyond 2030. By 2035, the share of coal in total energy supply would need to fall by at least 55%, oil by 15% and gas by 5%, compared with 2025 levels. By 2040, the respective reductions would need to reach at least 75%, 30% and 35%.

Coal-fired electricity generation would need to decline by at least 75% by 2035 and be effectively phased out globally by 2040.

Methane emissions, another major contributor to warming, would need to fall by at least 25% by 2035 and 40% by 2040, relative to 2025 levels.

UNEP also calls for stronger electricity grids, energy storage, electrification and efficiency measures, alongside policies that support a transition away from fossil fuels.

Can removing carbon dioxide bring temperatures back down?

Cutting emissions alone would not be sufficient to return temperatures to 1.5°C under the report’s lowest-overshoot scenario. It would also require removing carbon dioxide from the atmosphere and storing it permanently.

UNEP estimates that around 320 gigatonnes of carbon dioxide would need to be removed over the course of this century. That is equivalent to roughly eight years of global carbon dioxide emissions at 2024 levels.

Carbon removal could include biological approaches, such as restoring forests, and technological methods that capture carbon dioxide and store it underground or through mineralisation.

However, the report warns that the scale of removal required presents significant technological and socioeconomic challenges. The feasibility of delivering it remains uncertain.

This makes rapid emissions reductions essential. Carbon removal would need to complement cuts in greenhouse gas emissions rather than serve as a substitute for them.

What progress has climate action made?

Despite the gap between current commitments and the required cuts, UNEP says evidence from existing climate policies shows that faster reductions are possible.

The report draws on more than 220 policy evaluations. Policies assessed in the electricity sector reduced emissions by an average of 9%, while economic instruments, including carbon taxes and emissions trading schemes, delivered reductions of 5% to 13% across sectors during the periods evaluated.

These results were concentrated in particular countries, sectors and periods. UNEP says governments need to replicate and expand successful measures to achieve sustained reductions at a global scale.

The report also points to goals agreed during the first Global Stocktake under the Paris Agreement, including tripling renewable energy capacity, doubling the annual rate of energy-efficiency improvements, transitioning away from fossil fuels in energy systems, reducing non-carbon dioxide emissions and halting and reversing deforestation.

The next phase of climate action could build on these commitments by extending targets to 2035 and 2040 and setting clearer, measurable benchmarks.

UNEP’s central finding is that the world can still reduce the scale and duration of the 1.5°C overshoot, but the opportunity depends on the speed of action now. Global emissions flattening out for a year is not the same as achieving the sustained, steep reductions needed to limit warming.