Ten Years After Paris: Progress, Delay and the Path Back to 1.5°C

For years, international climate diplomacy has faced scathing criticism for becoming an inflated machinery for producing commitments without implementation or accountability. There has been no clear commitment to securing the required flow of funds or investment. Consequently, much of the promised action to reduce emissions has remained underfunded and unfulfilled and adaptation is becoming inaccessible for developing countries.

The Paris Agreement replaced top-down emission allocations with nationally determined targets that each country must strengthen every five years (Paris Agreement, 2015, Article 4). It was built on the understanding that a cycle of national pledges, globally reviewed and progressively increased ambition will curtail and effectively cap high-warming trajectory.

On one measure, it has made a dent to temperature increase. In 2015, the Climate Action Tracker (CAT) projected about 3.6°C of warming by 2100 under the then-in-place national policies and commitments. Whereas, its latest estimates show the temperature increase around 2.6°C (CAT, 2025a). Not an insignificant drop when each tenth of a degree avoided means fewer heat extremes, smaller crop losses and a lower risk of crossing irreversible thresholds.

But the progress has not been able to sustain. Projections by CAT have shown little or no measurable improvement for four consecutive years. And its most recent 0.1°C drop, from 2.7°C to 2.6°C, came largely from a change in method rather than from new policy measures.

Pledges Are Bending the Curve, but Not Fast Enough

The 2026 NDC Synthesis Report, published on 27 October, covers 127 new national climate plans from 154 Parties, represents about 71% of global emissions. If fully implemented, global greenhouse gas emissions will be cut down to about 6% below 2019 levels by 2035. Meeting every conditional element would raise the cut to around 9% (UNFCCC, 2026) which is lower than last year’s estimates. Last year NDC synthesis report put the reductions at 17% for the 64 Parties covering only about 30% of emissions. And an update at COP30 estimated the global figure at 12% (UNFCCC, 2025). The difference reflects estimation based on more comprehensive data, since the earlier estimates had to rely on modelling of national plans rather than actual submitted plans. These pledges are merely tenth of required emission cuts. Pathways for 1.5°C require a cut of about 60% by 2035 (IPCC, 2023).

The quality of national plans has, however, noticeably improved. Almost every new NDC sets out domestic mitigation measures and most are now linked to net zero targets between 2040 and 2070. If those long-term targets were also met, the synthesis estimates end-of-century warming of 1.7–2.3°C.

1.5°C Will Be Exceeded

Human-induced warming increased to an estimated 1.37°C above the 1850–1900 average in 2025, increasing at approximately 0.27°C per decade (Forster et al., 2026). The Paris goal refers to long-term average warming rather than to single hot years. This is the main reason the threshold has not yet been technically breached. At the current rate, it will be crossed around 2030. Emissions Gap Report 2026 by UNEP concludes that limiting to 1.5°C is no longer possible.

Peak Warming Is Now the Measure That Matters

UNEP sets out a pathway to keep overshoot as small and short as possible. Warming would peak at around 1.7–1.8°C near mid-century, with a 50% chance of returning to 1.5°C or below by 2100. This would require global emissions to fall by 18% by 2030, 45% by 2035 and 69% by 2040 - compared with 2025 levels. Even if countries fully deliver their NDCs pledges, including those dependent on international support, annual emissions would remain about 5 GtCO₂e above this pathway in 2030 and 16 GtCO₂e above it in 2035 (UNEP, 2026).

Bringing temperatures down would require large amounts of carbon dioxide to be removed from the atmosphere and stored permanently. Whether this can be achieved at the scale needed remains uncertain (UNEP, 2026). Also to note that falling temperatures would not undo all the damage already caused. Species lost to extinction would not return, while some ice-sheet loss and the resulting sea-level rise would persist for centuries (IPCC, 2023).

Why Progress Has Stalled

The early gains in emissions fall came mostly from the power sector with increasing share of renewables. Decarbonising heavy industry, freight and agriculture is harder because the costs fall on identifiable industries and workers. Governments facing short electoral cycles, inflation and energy-price pressures have been slow to impose those costs.

Although clean energy is growing fast but is mostly meeting new demand rather than replacing fossil fuels. Global energy supply rose 1.7% in 2025 and every major source, including coal, oil and gas, reached a record high. Fossil fuels supplied over 80% of total energy supply (Energy Institute, 2026). This measure understates the useful energy delivered by renewable electricity but shows how little displacement has happened. Much hyped transition of energy is yet to take place in real sense.

Geopolitics has added pressure and some additional unique challenges. Energy-security concerns since 2022 have renewed investment in fossil fuel supply. Many developing countries face a dilemma of decarbonising while expanding energy access and security.

The Next Decade Will Be Judged on Delivery

The first decade of Paris showed that collective commitments can shift projected warming. The second will be judged on implementation. Governments need to legislate the policies that close the gap between the 2.8°C and 2.6°C pathways. And the next round of NDCs has to move the 2035 figure towards the 60% cuts. Much of that depends on finance reaching the developing countries whose conditional targets rely on it.

Some of these questions will be debated at COP31, opening soon in Antalya. Whether the global community can agree on more ambitious targets and match them with credible action - remains to be seen!