- Japan 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
- 1Japan’s risk is seismic, climatic and demographic at once
- 2Key findings
- 3Systems and sectors at baseline
- 4Risks and capability
- 5Great earthquake in an ageing region
- 6Lenses and readings
- 7The 2027 agenda
- 8Systems in depth
- AMethodology
- BData appendix
- CReferences and record
- ·Complete edition, for print
S.1Abstract
Japan enters 2027 with record-low emissions, a shrinking and ageing population and one of the world’s most demanding hazard regimes. Greenhouse-gas emissions fell to 1,071 Mt CO₂e in FY2023, 23.3% below FY2013 and 27.1% lower once forest removals are counted, as renewables and nuclear together passed 30% of electricity12. The country has set reductions of 60% by FY2035 and 73% by FY2040 against FY20133. Yet Japan still imports almost all of its fuel, grows only 38% of its food on a calorie basis16 and faces a Nankai Trough megaquake that the national evaluation puts at a high probability within thirty years10. 2024 was the warmest year on record7, heatstroke sent about 97,600 people to hospital by ambulance in the summer of 202412, and the January 2024 Noto Peninsula earthquake showed how an ageing, remote region loses water, roads and care at once11. This Baseline Edition fixes the reference state for Japan’s water, energy, food, health and biodiversity systems, maps the couplings through which seismic, climate and supply shocks travel, and sets the questions the first operational edition will answer with Foundry evidence in Q1 2027. It ranks nothing and decides nothing.
S.2Key messages
Six readings that frame the Japan baseline, and the eight questions this edition answers, each with its status and source.
1,071 Mt CO₂e in FY2023, 23.3% below FY2013, or 27.1% net of removals.1
Where do emissions stand?Reported
A Nankai Trough megaquake could, in the worst case, cause about 298,000 deaths and ¥292 trillion in damage.9
How exposed is Japan to great earthquakes?Reported
Clean power passed 30%, but almost all fossil fuel is imported.25
How secure is energy supply?Reported
Japan grows 38% of its food on a calorie basis.16
How secure is food?Reported
About 97,600 heatstroke ambulance transports in summer 2024.12
Is heat now a health hazard?Reported
Remote, ageing regions lose water, roads and care at once after a large earthquake.11
What did Noto reveal?Reported
About a third of households hold earthquake cover; public assets are largely uninsured.22
Who carries the losses?Reported
An earthquake in an ageing region cutting water, power, roads and care together. SCN-JPN-EQL-01
What will Q1 2027 test first?Expert input
S.3Headline finding
ReportedEQL 4NRF-COUNTRY-JPN-2026-BASELINE-SEI-004
The 2025 revision of the Nankai Trough damage estimate gives a worst case of about 298,000 deaths and ¥292 trillion in damage, with tsunami the leading cause of death.
| Item | Bar, scaled to the largest value | Value |
|---|---|---|
| Deaths (thousands) | ≈298 | |
| Damage (¥ trillion) | ≈292 |
Source: Central Disaster Management Council working group9.
Such an event would strike the Pacific industrial belt, ports, refineries and power plants at once, and the national economy and global supply chains through them. Early evacuation and seismic retrofitting are estimated to cut deaths sharply, which makes preparedness a high-value capability89.
S.4At a glance
S.5What each steward reads in it
GCRI · KEY T
Technical Truth
The evidence supports a coupled reading of Japan’s risk: great earthquakes dominate the tail, climate extremes are rising, and ageing magnifies both.
GRF · KEY M
Public Meaning
For most people risk arrives as an earthquake alert, a heat wave or a typhoon warning.
GRA · KEY F
Capital Meaning
Readiness implications only. About a third of homes hold earthquake cover, public assets are largely uninsured, and climate disclosure standards apply from 2025.
NEXUS
Synthesis
Japan is strong at warning and response and thinner at keeping water, care and supply running for weeks.
S.6What this edition is, and is not
What this edition is
A baseline: the state of Japan’s water, energy, food, health and biodiversity systems in 2026, the dependencies that connect them, the risks that travel through them and the capabilities that hold them. It sets out the questions the operational series will answer.
What it is not
Not a national risk assessment, an official warning or a rating. It decides nothing about any institution or asset. Competent authorities keep every mandate they hold, and national ownership of the series is unaffected.
What comes next
Q1 2027 opens the operational series with a sealed Foundry evidence cut. Each later edition reports what changed against this baseline, new 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
- 1Ministry of the Environment and National Institute for Environmental Studies (eds.), Japan’s National Greenhouse Gas Emissions and Removals in FY2023. MoE, Tokyo, April 2025.back
- 2Ministry of the Environment (ed.), Progress of the Plan for Global Warming Countermeasures in FY2023. MoE, Tokyo, 2025.back
- 3Government of Japan (ed.), Japan’s Nationally Determined Contribution (targets for FY2035 and FY2040). Submission to the UNFCCC, February 2025.back
- 16Ministry of Agriculture, Forestry and Fisheries (ed.), Food self-sufficiency ratio, FY2023. MAFF, Tokyo, August 2024.back
- 10Headquarters for Earthquake Research Promotion (ed.), Long-term evaluation of earthquakes along the Nankai Trough (revised). MEXT, Tokyo, 2025.back
- 7Japan Meteorological Agency (ed.), “Characteristics of the climate in Japan in 2024.” JMA, Tokyo, January 2025.back
- 12Fire and Disaster Management Agency (ed.), “Heatstroke emergency transports, May–September 2024.” FDMA, Tokyo, October 2024.back
- 11Cabinet Office (ed.), “Damage situation of the 2024 Noto Peninsula Earthquake.” Cabinet Office, Tokyo, retrieved 2026-09-30.back
- 9Central Disaster Management Council, Working Group on Nankai Trough Megaquake Countermeasures (ed.), Revised damage estimates for a Nankai Trough megaquake. Cabinet Office, Tokyo, March 2025.back
- 5Agency for Natural Resources and Energy (ed.), Annual Report on Energy (Energy White Paper) 2025. METI, Tokyo, 2025.back
- 22General Insurance Rating Organization of Japan (ed.), Earthquake insurance statistics, 2023. GIROJ, Tokyo, 2024.back
- 8Cabinet Office (ed.), White Paper on Disaster Management 2025. Cabinet Office, Tokyo, 2025.back
- 15Statistics Bureau of Japan (ed.), Population Estimates as of 1 October 2024. Ministry of Internal Affairs and Communications, Tokyo, 2025.back