- Global Climate 2026
- Executive summary
Executive summary
The edition on a few pages: the abstract, the key messages, the headline finding and what each steward reads in it.
Contents
- ·Edition home
- ·Executive summary
- 1Climate sets the terms for the other systems
- 2Key findings
- 3Systems and sectors at baseline
- 4Risks and capability
- 5A strong El Niño on a 1.5 °C background
- 6Readings from the other desks
- 7The 2027 agenda
- 8Systems in depth
- AMethodology
- BData appendix
- CReferences and record
- ·Complete edition, for print
S.1Abstract
The world enters 2027 with a climate that is warmer than in any year before 2023, still warming, and about to be pushed higher by a strong El Niño. 2025 was the third-warmest year in the ERA5 record at 1.47 °C above the pre-industrial level, and 2023 to 2025 was the first three-year period above 1.5 °C1. Human-induced warming reached 1.37 °C in 2025 and is rising by about 0.27 °C a decade7. Carbon dioxide averaged 423.9 ppm in 2024 on the WMO network, 52% above the pre-industrial level; the 2025 annual value was not bound at the close31. Fossil CO2 emissions are projected to rise about 1.0% in 2025, and the remaining budget for a 50% chance of staying below 1.5 °C is 170 GtCO2 in the Global Carbon Budget and 130 GtCO2 in the Indicators of Global Climate Change, three to four years at current emissions67. More than 91% of the excess heat is in the ocean, which reached a record heat content in 20252. August 2026 was 1.65 °C above the pre-industrial level, the 12-month mean to August was 1.48 °C, and NOAA gives a chance above 90% of a very strong El Niño in the northern fall and winter of 2026 to 20274748. Impacts are concentrated. 2025 was one of the driest years for rivers in more than three decades24, modelled heat deaths in 854 European cities reached 430,365 over 2000 to 202523, and 645 million people faced hunger in 202526. Climate finance reached USD 1.9 trillion in 2023, with adaptation at USD 65 billion20. This baseline sets out what the evidence supports and where it is thin. It ranks no country and recommends no policy.
S.2Key messages
Six readings that frame the climate baseline, and the eight questions this edition answers, each with its status and source.
2025 was 1.47 °C above pre-industrial in ERA5, third-warmest on record.1
How warm is the world?Reported
Yes. Human-induced warming is 1.37 °C and rising about 0.27 °C a decade.7
Is it still warming?Reported
Yes. Carbon dioxide, methane and nitrous oxide reached records; CO2 averaged 423.9 ppm in 2024 on the WMO network.31
Are gases still rising?Reported
About 130 to 170 GtCO2 for a 50% chance of 1.5 °C, three to four years at current emissions.67
How much carbon budget is left?Reported
More than 91% is in the ocean, at a record in 2025.2
Where is the heat?Reported
Heat deaths, river deficits and hunger fall hardest on older people, exposed workers and low-income regions.212426
Who bears the impacts?Reported
119 countries report multi-hazard systems; only 43% of small island developing States do.25
Is early warning in place?Reported
A strong El Niño on a 1.5 °C background. SCN-GS07-ELN-01
What will 2027 test first?Expert input
S.3Headline finding
ReportedEQL 4NRF-SECTOR-CLIMATE-GLOBAL-2026-BASELINE-CLI-005
From the start of 2026, the remaining carbon budget for a 50% chance of limiting warming to 1.5 °C is 170 GtCO2 in the Global Carbon Budget and 130 GtCO2 in the Indicators of Global Climate Change.
| Item | Bar, scaled to the largest value | Value |
|---|---|---|
| Global Carbon Budget 2025 | 170 | |
| Indicators of Global Climate Change 2025 | 130 |
The two assessments agree that the budget is nearly exhausted: about 4 years at the 2025 emissions level in one, a little more than 3 years in the other. They differ by 40 GtCO2, and each issuer states its own method. The budget can also change by about 200 GtCO2 depending on how far non-CO2 emissions fall7.
S.4At a glance
S.5What each steward reads in it
GCRI · KEY T
Technical Truth
The evidence supports reading climate as the condition layer of the WEFH+B system.
GRF · KEY M
Public Meaning
For most people climate risk arrives as a hotter summer, a failed harvest or a flooded street.
GRA · KEY F
Capital Meaning
Readiness implications only. Event losses are rising, adaptation finance is small beside mitigation finance and the carbon budget is nearly used.
NEXUS
Synthesis
The climate system is well measured at the level of global indicators and thinly measured at the level of regional impacts, adaptation spending and tested capability.
S.6What this edition is, and is not
What this edition is
A baseline: the 2026 state of the world’s climate and Earth system and the couplings through which it carries risk into other systems. It synthesises published evidence and ranks no country, company or asset.
What it is not
Not a ranking of countries, a forecast of weather, a projection of any national outcome, an attribution of any single event or an assessment of any government, company or negotiating position. Climate policy and adaptation rest with national authorities, regulators and the parties to the climate treaties.
What comes next
National, regional and sector evidence feeds the 2027 climate edition through the federation. Each edition reports what changed against this baseline: observations, source revisions, method changes, scenario updates and corrections.
Notes
Numbers are the edition’s reference numbers, so a note reads the same in every chapter. The full list, with every source and its licence, is in Annex C. Annex C, references
- 1Copernicus Climate Change Service (C3S), ECMWF (ed.), Global Climate Highlights 2025 (published 14 January 2026, updated 28 January 2026). ECMWF, Bonn. DOI 10.24381/b3nm-p354. Observation year 2025. Opened in full (PDF). Accessed 2026-11-03. doi:10.24381/b3nm-p354back
- 7Forster, P.M. et al., Indicators of Global Climate Change 2025: annual update of key indicators of the state of the climate system and human influence, Earth System Science Data 18, 3889 to 3933, 2026. DOI 10.5194/essd-18-3889-2026. Observation year 2025. Opened in full (PDF). Accessed 2026-11-03. doi:10.5194/essd-18-3889-2026back
- 31WMO (ed.), Greenhouse Gas Bulletin No. 21 (16 October 2025). World Meteorological Organization, Geneva. Observation year 2024. Opened: publication page and bulletin summary with the headline values (CO2 423.9 ppm, CH4 1942 ppb, N2O 338.0 ppb). Accessed 2026-11-03.back
- 6Friedlingstein, P. et al., Global Carbon Budget 2025, Earth System Science Data 18, 3211 to 3288, 2026. Global Carbon Project. DOI 10.5194/essd-18-3211-2026. Observation year 2024 (2025 preliminary). Opened in full (PDF). Accessed 2026-11-03. doi:10.5194/essd-18-3211-2026back
- 2WMO (ed.), State of the Global Climate 2025 (publication page and press release of 23 March 2026). World Meteorological Organization, Geneva. Observation year 2025. Opened: page and press release; the full report was not opened. Accessed 2026-11-03.back
- 47Copernicus Climate Change Service (C3S), Surface air temperature for August 2026 (monthly climate bulletin, September 2026; the page shows no publication date, placed in September 2026 from its file path). ECMWF, Bonn. Observation year 2026. Opened: bulletin page. Accessed 2026-11-03.back
- 48NOAA Climate Prediction Center, ENSO diagnostic discussion of 10 September 2026. National Weather Service, College Park. Observation year 2026. Opened: discussion page. Accessed 2026-11-03.back
- 24WMO (ed.), State of Global Water Resources 2025 (publication page, 17 September 2026). World Meteorological Organization, Geneva. Observation year 2025. Opened: publication page with key messages; the full report was not opened. Accessed 2026-11-03.back
- 23Barnes, G. et al., Heat-related urban mortality attributable to human-induced climate change in Europe from 2000 to 2025, Nature Health 4, 2026. Observation year 2025. Opened: abstract through PubMed and Europe PMC. A preprint version of the study reports different totals (463,730 deaths; 45% to 64%) and is not used. Accessed 2026-11-03.back
- 26FAO, IFAD, UNICEF, WFP and WHO (eds.), The State of Food Security and Nutrition in the World 2026, joint news release of 21 July 2026 (as published by WHO). Rome. Observation year 2025. Opened: news release; the report was not opened. Accessed 2026-11-03.back
- 20Naran, B. et al., Global Landscape of Climate Finance 2025 (23 June 2025). Climate Policy Initiative, London. Observation year 2023. Opened: publication page with the headline figures; the report was not opened. Accessed 2026-11-03.back
- 21WHO (ed.), Climate change and health, fact sheet (12 October 2023). World Health Organization, Geneva. Observation year 2023. Opened: fact sheet. Accessed 2026-11-03.back
- 25UNDRR and WMO (eds.), Global Status of Multi-Hazard Early Warning Systems 2025 (publication page and press release of 12 November 2025). Geneva. Observation year 2025. Opened: page and press release; the report was not opened. Accessed 2026-11-03.back
