Shared spaces change together
Part I describes systems and their couplings. It ranks no country or operator and assesses no authority.
Contents
- ·Edition home
- ·Executive summary
- 1Shared spaces change together
- 2Key findings
- 3Systems and sectors at baseline
- 4Risks and capability
- 5High seas treaty implementation and the first protected areas
- 6Readings from the other desks
- 7The 2027 agenda
- 8Systems in depth
- AMethodology
- BData appendix
- CReferences and record
- ·Complete edition, for print
1.1The questions this part answers
Key questions
- Where is ocean and polar commons risk concentrated?
- Which couplings carry ocean and polar commons shocks into other systems?
- Which ocean and polar commons capabilities hold under compound stress?
- What must 2027 evidence measure first?
In this part
- Narrative
- Headline finding
- Lead figure
- Five mechanism chapters
- Twelve-domain reading
- Sector screens
- Dependency matrix
- Risk objects
- Capability ladder
- Scenario
- Three lenses
- Portfolio
1.2The argument
The ocean, the poles, the high seas and orbit are usually reported one by one: sea ice by glaciologists, fish by fisheries bodies, seabed by a licensing authority, orbit by space agencies. The 2025 and 2026 evidence reads them as spaces that share causes and that share the gaps in how they are governed3611.
The physical signals line up. Arctic air temperature in the 2025 report year was the highest since 19003. Sea level is 115.2 mm above its 1993 level6. Reefs are passing a thermal threshold9 and surface ocean acidity has risen by 30 to 40% since the industrial era10.
Governance moves unevenly. The high seas treaty is in force11, the fisheries subsidies agreement is in force12, the shipping net-zero framework was adjourned41 and seabed exploitation rules are unfinished15. Only 1.45% of the high seas is covered by protected areas16.
The edition therefore asks the same four questions of every event: what was the common cause, how did it spread, what was shared, and what threshold was crossed. It takes no position on any claim and ranks no state.
Polar sea ice swings between large winter extents and small summer extents. The four bars are separate seasonal limits from different years and are not a series127.
| Item | Bar, scaled to the largest value | Value |
|---|---|---|
| Antarctic maximum, September 2025 | 17.81 | |
| Arctic maximum, March 2026 | 14.29 | |
| Arctic minimum, September 2025 | 4.6 | |
| Antarctic minimum, March 2025 | 1.98 |
Source: as cited in the note to this figure. Year 2025.
Figure ID FIG-STRATEGIC-COMMONS-GLOBAL-2026-BASELINE-01-003
1.3Twenty couplings between five systems
The ocean and polar commons-centred matrix types the twenty couplings between the five core systems, read for their ocean and polar commons content. Strengths are Nexus estimates (ESTIMATED) from the cited evidence and analogue events; they set the graph that 2027 evidence will test.
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.
| From, to | WAT | ENE | FOO | HLT | BIO |
|---|---|---|---|---|---|
| WAT Water | · | WEAK cooling water | MODERATE aquaculture · irrigation | MODERATE coastal supply | MODERATE estuary flows |
| ENE Energy | WEAK desalination | · | MODERATE fishing fleets · cold chain | WEAK ports | STRONG emissions · acidification · warming |
| FOO Food | WEAK nutrient runoff | WEAK fuel use | · | MODERATE seafood nutrition | STRONG fishing pressure |
| HLT Health | WEAK effluent | WEAK workforce | WEAK labour | · | WEAK residues |
| BIO Biodiversity | MODERATE coastal buffers | WEAK offshore siting | STRONG reef and stock habitat | WEAK coastal protection | · |
| 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
- 01
CLI → BIO → FOO
Warming and acidification stress reefs and the habitats that support fish.
Reported reef and planetary boundary reports910
- 02
CLI → INF
Ice loss and ocean warming raise sea level and coastal exposure.
- 03
TRD → BIO
Subsidy and shipping rules shape fishing pressure and emissions at sea.
- 04
MIN → BIO
Seabed recovery would disturb deep-sea habitat in licence areas.
- 05
INF → INF
Launch growth and debris raise collision risk in shared orbits.
Reported ESA 202617
1.4Reinforcing loops
A shock entering either system of a loop can return amplified through the other.
| Loop | First direction | Second direction |
|---|---|---|
| FOO and BIO | Food to biodiversity: fishing pressure | Biodiversity to food: reef and stock habitat |
| 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
- 3NOAA (ed.), Arctic Report Card 2025 (summary page; air temperature, sea ice, precipitation and Greenland ice sheet findings). National Oceanic and Atmospheric Administration, Silver Spring. Observation year 2025. Accessed 2026-11-03.back
- 6NASA (ed.), Global Mean Sea Level (key indicator page; 115.2 mm rise since 1993; current rate 4.4 mm a year). National Aeronautics and Space Administration, Pasadena. Observation year 2024. Accessed 2026-11-03.back
- 11United Nations (ed.), Agreement under the UN Convention on the Law of the Sea on the conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction (status page, UN Treaty Collection; entry into force 17 January 2026; 145 signatories and 105 parties as shown on the page when read). United Nations, New York. Observation year 2026. Accessed 2026-11-03.back
- 9National Oceanography Centre (ed.), Global Tipping Points Report 2025 reveals first Earth system tipping point reached (summary page; warm-water reefs passing their thermal tipping point, central estimate 1.2 °C, range 1 to 1.5 °C, warming about 1.4 °C; more than 160 scientists at 87 institutions). NOC, Southampton. Observation year 2025. Accessed 2026-11-03.back
- 10Stockholm Resilience Centre (ed.), Seven of nine planetary boundaries now breached (Planetary Health Check 2025 news page of 24 September 2025; ocean acidification breached for the first time; surface pH down about 0.1 units). Stockholm Resilience Centre, Stockholm. Observation year 2025. Accessed 2026-11-03.back
- 12WTO (ed.), Acceptances of the Protocol Amending the Marrakesh Agreement, Agreement on Fisheries Subsidies (acceptance list; entry into force 15 September 2025; 123 acceptances; latest date shown 20 July 2026). World Trade Organization, Geneva. Observation year 2026. Accessed 2026-11-03.back
- 41Herbert (ed.), MEPC ES2 Meeting Brief (law-firm briefing page dated 2026-01-20; adjournment of the Net-Zero Framework session by a vote of 57 in favour, 49 against and 21 abstentions after a one-year adjournment motion; opened as a pre-close source for [13]). Herbert, law-firm briefing. Observation year 2025. Accessed 2026-11-03.back
- 15International Seabed Authority (ed.), 31st Session 2026 (session page; Council part I 9 to 19 March 2026 and part II 13 to 24 July 2026; decision titles on exploitation rules and contract extensions; decision texts not read). ISA, Kingston. Observation year 2026. Accessed 2026-11-03.back
- 16UNEP-WCMC and IUCN (eds.), Protected Planet, marine protected areas page (areas beyond national jurisdiction 61% of the ocean; 1.45% covered by protected areas and other effective area-based measures). UNEP-WCMC, Cambridge. Observation year 2026. Accessed 2026-11-03.back
- 1NSIDC (ed.), Arctic sea ice has likely reached its minimum extent for 2025 (Sea Ice Today analysis, relayed by CIRES; minimum 4.60 million km² on 10 September 2025; tenth lowest in the 47-year record). National Snow and Ice Data Center, Boulder. Observation year 2025. Accessed 2026-11-03.back
- 2US National Ice Center (ed.), Arctic Sea Ice at Minimum and Maximum Extents, 2025 to 2026 (press release; USNIC 3-day minimum 4.86 million km² in September 2025; 2026 maximum 14.53 million km² on 6 to 8 March by USNIC and 14.29 million km² on 15 March by NSIDC). US National Ice Center, Suitland. Observation year 2026. Accessed 2026-11-03.back
- 7NSIDC (ed.), Sea Ice Today analyses (Antarctic maximum 17.81 million km² on 17 September 2025, third lowest; Antarctic minimum 1.98 million km² on 1 March 2025, tied second lowest). National Snow and Ice Data Center, Boulder. Observation year 2025. Accessed 2026-11-03.back
- 5WMO (ed.), 2025 set to be second or third warmest year on record (update for COP30; sea level rate from 2.1 mm a year in 1993 to 2002 to 4.1 mm a year in 2016 to 2025; over 90% of excess energy in the ocean). World Meteorological Organization, Geneva. Observation year 2025. Accessed 2026-11-03.back
- 42NOAA (ed.), NOAA advances review of first-ever deep seabed mining commercial recovery application (news release of 19 August 2026; application submitted 6 February 2026; found in full compliance with the information requirements of the Deep Seabed Hard Mineral Resources Act; opened as a pre-close source for [14]). National Oceanic and Atmospheric Administration, Silver Spring. Observation year 2026. Accessed 2026-11-03.back
- 17European Space Agency (ed.), ESA Space Environment Report 2026 (report page of 14 September 2026; data to end 2025; health index from about 4 to about 50; more than 300 launches and over 4,000 payloads in 2025). ESA, Darmstadt. Observation year 2025. Accessed 2026-11-03.back
