- Global Climate 2026
- Chapter 3
Systems and sectors at baseline
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
3.1Where each system stood at evidence close
CLI · Climate
Global surface air temperature above pre-industrial (ERA5)
1.47°Cthird-warmest year; 2023 to 2025 mean 1.52 °C.
Reported2025C3S1
CLI · Greenhouse gases
Global carbon dioxide concentration (WMO network)
423.9ppm52% above pre-industrial; the 2025 annual value is not bound at the close.
Reported2024WMO31
ENE · Emissions
Fossil CO2 emissions, with 2025 projected up about 1.0%
37.8GtCO2with land use, 42.4 GtCO2.
Reported2024GCB6
CLI · Ocean
Share of excess heat stored in the ocean
>91%ocean heat content at a record in 2025.
Reported2025WMO2
HLT · Health
Modelled heat deaths, 854 European cities, 2000 to 2025
430,365deathsjust over half attributed to human-induced warming.
Reported2025Barnes et al.23
SYS · Cross-system
Chance of a very strong El Niño in the northern fall and winter of 2026 to 2027
>90%NOAA outlook of 10 September 2026.
Scenario2026NOAA48
3.2Domain posture
Each of the twelve coupled domains is read through climate, in words, not scored. The coupling column names the dependency that carries climate risk into each domain.
| Domain | Posture at baseline | Coupling | Status |
|---|---|---|---|
| WAT | 2025 was one of the driest years for rivers in more than three decades; the past seven years had the fewest normal flows since 1991. | CLI → WAT | Reported EQL 4 |
| ENE | Fossil CO2 emissions 37.8 GtCO2 in 2024, projected up about 1.0% in 2025; the supply and demand side is read in the energy edition. | ENE → CLI | Reported EQL 4 |
| FOO | 645 million faced hunger in 2025; the projections omit El Niño effects in 2026 and 2027. | CLI → FOO | Reported EQL 4 |
| HLT | Modelled heat deaths of 430,365 in 854 European cities over 2000 to 2025; 1.2 billion workers face workplace heat risk. | CLI → HLT | Reported EQL 4 |
| BIO | Warm-water coral reefs crossing a thermal tipping point; six of nine planetary boundaries transgressed. | CLI ↔ BIO | Reported EQL 4 |
| CLI | The core system: 1.47 °C above pre-industrial in 2025, record gases, nearly spent budget. | the core system | Reported EQL 5 |
| INF | Storm, fire and flood damage: Hurricane Melissa damage equal to 41% of Jamaica’s GDP; over USD 60 billion for the Los Angeles fires. | CLI → INF | Reported EQL 3 |
| FIN | USD 1.9 trillion of climate finance in 2023, adaptation USD 65 billion; losses from events are not on one basis. | CLI ↔ FIN | Reported EQL 3 |
| DAT | Long observing records underpin every indicator; programme continuity is threatened by funding decisions. | DAT → CLI | Reported EQL 3 |
| AIC | Machine-learning forecasting and compute demand both touch the climate system; evidence is not consolidated here. | AIC ↔ CLI | Expert input EQL 1 |
| MIN | Mitigation and adaptation technologies draw on minerals; the evidence is not consolidated here. | MIN ↔ CLI | Expert input EQL 1 |
| TRD | Trade carries climate shocks into food and goods markets; the evidence is not consolidated here. | CLI → TRD | Expert input EQL 2 |
3.3Sector screens
All sixteen sectors are screened for their dependence on climate, on the same grammar as every national edition. The evidence column describes coverage of the baseline evidence, not the performance of the sector.
| Code | Sector | Baseline evidence | Exposure to watch | Evidence coverage |
|---|---|---|---|---|
| GS-00 | Cross-system | climate sets conditions for all five core systems28 | concurrent extremes | PARTIAL |
| GS-01 | Water | one of the driest years for rivers in 35 years24 | swings between deficit and flood | GOOD |
| GS-02 | Energy | fossil CO2 projected up about 1.0% in 20256 | heat-driven demand | GOOD |
| GS-03 | Food | 645 million facing hunger in 202526 | El Niño and weather extremes | PARTIAL |
| GS-04 | Health | modelled heat deaths in 854 European cities23 | heat waves; dengue | GOOD |
| GS-05 | Finance | USD 1.9 trillion of climate finance in 202320 | uninsured event losses | PARTIAL |
| GS-06 | Development | 3.3 to 3.6 billion in highly vulnerable contexts8 | compounding disasters | PARTIAL |
| GS-07 | Climate | human-induced warming of 1.37 °C in 20257 | overshoot of 1.5 °C | GOOD |
| GS-08 | Disaster | 119 countries report early warning systems25 | cascading losses | GOOD |
| GS-09 | Infrastructure | Hurricane Melissa damage equal to 41% of Jamaica’s GDP3 | coastal and flood damage | THIN |
| GS-10 | Cities | heat deaths in 854 European cities23 | urban heat | PARTIAL |
| GS-11 | Biodiversity | reefs crossing a thermal tipping point at 1.4 °C16 | ocean heat and acidification | PARTIAL |
| GS-12 | Earth observation | observing programmes threatened by funding decisions7 | continuity of missions | PARTIAL |
| GS-13 | Cyber and digital | no consolidated evidence in this edition | loss of warning services | THIN |
| GS-14 | Policy | 194 Parties to the Paris Agreement28 | overshoot and ambition gap | PARTIAL |
| GS-15 | Science | twelve indicator sets tracked each year7 | next IPCC assessment | GOOD |
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
- 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
- 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
- 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
- 8IPCC (ed.), Climate Change 2023: Synthesis Report (Sixth Assessment Report, longer report). Intergovernmental Panel on Climate Change, Geneva. Observation year 2011 to 2020 (warming) and 2019 (emissions). Opened in full (PDF). 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
- 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
- 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
- 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
- 3WMO (ed.), State of the Global Climate 2025, supplement on extreme events and impacts (May 2026). World Meteorological Organization, Geneva. Observation year 2025. Opened in full (PDF). Accessed 2026-11-03.back
- 16Global Tipping Points Report 2025 (160 authors, University of Exeter), key messages. Global Tipping Points project, Exeter. Observation year 2025. Opened: project page with key messages; the full report was not opened. Accessed 2026-11-03.back
- 28United Nations Treaty Collection (ed.), Paris Agreement, Paris, 12 December 2015 (status page). United Nations, New York. Observation year 2026 (status at access). Opened: status page. Accessed 2026-11-03.back
