France’s risk is coupled, not cumulative

Part I describes systems and their couplings. It assesses no authority and ranks no region or territory.

7 min read2 figures2 tables18 notesNR-COUNTRY-FRA-2026-BASELINE.

Contents
  1. ·Edition home
  2. ·Executive summary
  3. 1France’s risk is coupled, not cumulative
    1. 1.1 The questions this part answers
    2. 1.2 The argument
    3. 1.3 Twenty couplings between five systems
    4. 1.4 Reinforcing loops
  4. 2Key findings
  5. 3Systems and sectors at baseline
  6. 4Risks and capability
  7. 5Hot, dry summer with low river flows
  8. 6Lenses and readings
  9. 7The 2027 agenda
  10. 8Systems in depth
  11. AMethodology
  12. BData appendix
  13. CReferences and record
  14. ·Complete edition, for print

1.1The questions this part answers

Key questions

  • Where is Canada’s risk concentrated, and in which systems?
  • Which couplings carry shocks from one system to the next?
  • Which capabilities hold under compound stress, and which are only documented?
  • What must the 2027 programme measure first?

In this part

  • Narrative
  • Headline finding
  • Lead figure
  • Twelve-domain reading
  • Sector screens
  • Dependency matrix
  • Risk objects
  • Capability ladder
  • Scenario
  • Three lenses
  • Portfolio

1.2The argument

France usually meets its climate risks one at a time: a heatwave, a drought, a flood, a fire season. This baseline reads them as one coupled system. 2022 was the warmest year on record in metropolitan France8; in the same year rivers ran low, more than 60,000 hectares burned20, clay soils shrank under thousands of houses, and the nuclear fleet produced less electricity than in any year since 198825.

The forcing is now planned for, not only observed. The third national adaptation plan, adopted in 2025, prepares the country for a reference trajectory of about +4 °C by 2100 in metropolitan France910. The 2003 heatwave, which killed more than 70,000 people across Europe39, remains the reference case: heat caused more than 3,700 deaths in summer 2024, three quarters of them among people aged 75 and over4.

Water couples the other systems most directly. Agriculture accounts for about 58% of freshwater consumed and power-plant cooling for about 12%12; in hot, dry summers both compete with drinking water for the same low flows. The 2023 Plan Eau sets a 10% cut in withdrawals by 203011. About 17.1 million residents are exposed to river flooding22.

The energy system is low-carbon and water-dependent. Electricity was about 95% low-carbon in 2024, and power-sector emissions fell 26% as nuclear and hydro output recovered17. But most reactors are cooled by rivers or the sea, and heat limits on discharge temperatures can force output cuts just when demand for cooling rises. Total emissions fell only 1.8% in 2024, about half the pace the 2030 target needs13.

Losses fall on a shared national regime. Since 1982 the CatNat system has spread the cost of natural disasters across all property policyholders15. Drought subsidence of clay soils now threatens about 10.4 million detached houses21, and natural-event claims reached about €10 billion in 2022, the highest since 199913. Overseas, Cyclone Chido devastated Mayotte in December 202426.

This edition therefore treats French risk as a property of couplings, between heat, rivers, reactors, harvests, houses and health, rather than a list of separate hazards. The matrix, risk objects, capability ladder and scenario that follow ask where a shock travels next and who holds the capability to stop it.

Figure 1.1Who consumes France’s freshwater? Share of water consumed, by use (%)

Agriculture consumes most freshwater, mainly in summer when river flows are lowest. Power plants withdraw large volumes for cooling but return most of them, warmer12.

ItemBar, scaled to the largest valueValue
Agriculture58
Drinking water26
Power-plant cooling12
Industry4

Source: as cited in the note to this figure. Year recent.

Figure ID FIG-COUNTRY-FRA-2026-BASELINE-01-003

10%

cut in withdrawals targeted by 203011

≈95%

low-carbon electricity, 20247

2022record

warmest year8

17.1million

residents exposed to river flooding22

1.3Twenty couplings between five systems

The France matrix types the twenty couplings between the five core systems. Strengths are Nexus estimates from the cited evidence and analogue events; they set the starting graph that the Q1 2027 Foundry cut will test.

Figure 1.2Couplings between the five systems

Each line is one coupling from one system to another, drawn by the strength the edition assigns. Strengths are Nexus estimates from the cited evidence and analogue events.

  • Strong
  • Moderate
  • Weak

Source: this edition’s coupling matrix (Table 1.1); status Estimated.

Table 1.1Coupling matrix: from the row system to the column system
From, toWATENEFOOHLTBIO
WAT Water·STRONG
nuclear cooling · hydro		STRONG
irrigation · rain-fed yield		MODERATE
drinking water		STRONG
flows · wetlands
ENE EnergyMODERATE
pumping · treatment		·STRONG
fuel · fertiliser · cold chain		STRONG
facility power · cooling		MODERATE
reservoirs · land use
FOO FoodMODERATE
withdrawals · nutrients		WEAK
biofuel feedstock		·STRONG
nutrition · food safety		STRONG
land conversion
HLT HealthWEAK
workforce		WEAK
workforce		MODERATE
labour · disease		·WEAK
residues
BIO BiodiversitySTRONG
regulation · filtration		MODERATE
fire on lines · biomass		STRONG
pollination · soils		MODERATE
zoonoses · smoke		·
Strength: strong, moderate or weak; a Nexus estimate (status Estimated) from cited evidence and analogue events. The scale is defined in Annex A.

Transmission paths

  1. 01

    CLI → WAT → ENE

    Heat and low flows force nuclear output cuts.

    Reported summer 202225

  2. 02

    CLI → HLT

    Heatwaves raise deaths among older people.

    Reported summers 2023–202445

  3. 03

    CLI → WAT → FIN

    Drought shrinks clay soils, cracks houses and raises CatNat claims.

    Reported 20221321

  4. 04

    WAT → FOO

    Drought and irrigation limits cut harvests.

    Inferred 2022

  5. 05

    CLI → BIO

    Wildfire spreads to regions once spared.

    Reported 2022 fires20

1.4Reinforcing loops

A shock entering either system of a loop can return amplified through the other.

Table 1.2Pairs of systems where both directions are rated strong
LoopFirst directionSecond direction
WAT and BIOWater to biodiversity: flows · wetlandsBiodiversity to water: regulation · filtration
FOO and BIOFood to biodiversity: land conversionBiodiversity to food: pollination · soils
A causal-loop reading of the matrix (Sterman, Business Dynamics, 2000): structural, from estimated strengths, not a measured feedback.

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.

  1. 8Météo-France (ed.), Bilan climatique de l’année 2022 en France. Météo-France, Saint-Mandé, January 2023.back
  2. 20J. San-Miguel-Ayanz et al. (eds.), Forest Fires in Europe, Middle East and North Africa 2022. Joint Research Centre, Ispra, 2023.back
  3. 25RTE (ed.), Bilan électrique 2022. RTE, Paris, February 2023.back
  4. 9Ministère de la Transition écologique (ed.), Troisième plan national d’adaptation au changement climatique (PNACC-3). MTE, Paris, March 2025.back
  5. 10Ministère de la Transition écologique (ed.), Trajectoire de réchauffement de référence pour l’adaptation au changement climatique (TRACC). MTE, Paris, 2024.back
  6. 39J.-M. Robine, S. L. K. Cheung, S. Le Roy et al., “Death toll exceeded 70,000 in Europe during the summer of 2003,” Comptes Rendus Biologies, vol. 331, pp. 171–178, 2008.back
  7. 4Santé publique France (ed.), Chaleur et santé : bilan de l’été 2024. Santé publique France, Saint-Maurice, 2024.back
  8. 12SDES (ed.), L’environnement en France : prélèvements et consommations d’eau. Service des données et études statistiques, Paris, retrieved 2026-09-30.back
  9. 11Gouvernement (ed.), Plan d’action pour une gestion résiliente et concertée de l’eau (Plan Eau). Paris, March 2023.back
  10. 22CGDD (ed.), Évaluation préliminaire des risques d’inondation : exposition de la population aux inondations par débordement de cours d’eau. Ministère de la Transition écologique, Paris.back
  11. 1Citepa (ed.), Rapport Secten, Gaz à effet de serre et polluants atmosphériques : bilan des émissions en France de 1990 à 2024, édition 2025. Citepa, Paris, 2025.back
  12. 7RTE (ed.), Bilan électrique 2024. RTE, Paris, February 2025.back
  13. 3Haut Conseil pour le Climat (ed.), Rapport annuel 2025. HCC, Paris, July 2025.back
  14. 15Parlement (ed.), Loi n° 82-600 du 13 juillet 1982 relative à l’indemnisation des victimes de catastrophes naturelles. Journal officiel, Paris, 1982.back
  15. 21CGDD (ed.), Retrait-gonflement des argiles : plus de 10 millions de maisons individuelles potentiellement très exposées. Ministère de la Transition écologique, Paris, 2021.back
  16. 13France Assureurs (ed.), Bilan des catastrophes naturelles et des événements climatiques 2022. France Assureurs, Paris, 2023.back
  17. 26Gouvernement (ed.), « Cyclone Chido à Mayotte » : communiqués et bilan, December 2024 – January 2025. Paris.back
  18. 5Santé publique France (ed.), Heat Waves and Health. Public Health Bulletin: A Review of Summer 2023. Santé publique France, Saint-Maurice, February 2024.back

Cite this chapter

Valadbaygi, S. (Ed.). (2026). Chapter 1: France’s risk is coupled, not cumulative. In France Systems Risk and Resilience Report 2026: The State of France’s Interdependent Systems (Baseline Edition 2026, Report No. NR-COUNTRY-FRA-2026-BASELINE) [Draft under review]. The Global Centre for Risk and Innovation (GCRI).

Every citation form of the whole report, BibTeX and RIS included, is on the edition home. Cite this report.

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