Did Termination Shock come true?
Partly. Termination Shock (2021) has a P(n) of 50% on Nearfi's P(n) Board, our estimate of the chance its future arrives within 20 years. Of its 5 tracked predictions, 1 have arrived and 1 are arriving. Its central premise, 'A private individual or company deploys stratospheric sulfur injection to cool the planet without international approval', is partly here. The next prediction is estimated to arrive around 2035.
Termination Shock is most prescient about its politics: private actors have already released sulfur dioxide into the stratosphere on a tiny scale, funded start-ups are preparing larger tests, and no body governs any of it. Its full-scale, border-launched programme, and a state attacking it, remain well beyond anything yet seen.
Read the review · 7.4/10 →
How this P(n) was calculated
P(n) is the chance that this work's future arrives within 20 years, by 2046. For each prediction we turn our estimate into a probability: arrived is 100%, diverged is 0%, and otherwise the low end of our 80% range counts as a 10% chance, the median year 50% and the high end 90%. Each prediction is weighted 1–5 by how pivotal it is to the story, and P(n) is the weighted average. P50 does the same by 2076. P(n), explained.
| Claim | Prediction · why this weight | Weight | Status · estimate | By 2046 | By 2076 |
|---|---|---|---|---|---|
| TSHOCK-1 | A private individual or company deploys stratospheric sulfur injection to cool the planet without international approval. Core premise: a billionaire's unilateral sulfur programme is the story's engine. |
5 | ARRIVING 2040 (2030–2065) | 60% | 94% |
| TSHOCK-2 | A state tries to stop another actor's stratospheric geoengineering programme by military force. Major: India's attempt to destroy the launcher drives the climax and the book's argument about sovereignty. |
4 | NEAR 2065 (2040–2120) | 20% | 58% |
| TSHOCK-3 | Vulnerable low-lying and small states form a coalition to push for solar geoengineering. Supporting: the pro-geoengineering coalition around the Queen shapes the politics, though the plot turns on Schmidt. |
3 | DIVERGED — | 0% | 0% |
| TSHOCK-4 | India and China contest their disputed Himalayan frontier with hand-to-hand fighting rather than firearms. Texture: the border fights build Laks's arc but are separate from the geoengineering plot. |
2 | ARRIVED arrived 2020 | 100% | 100% |
| TSHOCK-5 | Stratospheric sulfur injection is cheap enough that a single wealthy backer or small group of states could pay for it. Major: the plot only works if one rich man can afford to act alone. |
4 | NEAR 2035 (2030–2050) | 79% | 100% |
| P(n) = P20 = Σ(weight × chance by 2046) ÷ Σ weight = 8.9 ÷ 18 = 50% | |||||
| P50 = 13.0 ÷ 18 = 72% | |||||
Already here today (arrived 1, arriving ½, weighted): 25%.
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TSHOCK-1
A private individual or company deploys stratospheric sulfur injection to cool the planet without international approval.
Weight 5/5 · Core premise: a billionaire's unilateral sulfur programme is the story's engine.
Small-scale private releases already happen. Make Sunsets says it has flown 147 balloons carrying sulfur dioxide since February 2023, and the EPA has demanded information from it. Stardust Solutions has raised $75 million in total and is preparing for aircraft-based tests, though it says it will not run outdoor particle experiments without government approval. Nothing yet approaches a climatically meaningful release, and the date depends on whether regulators and states act before a funded actor does. 123
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TSHOCK-2
A state tries to stop another actor's stratospheric geoengineering programme by military force.
Weight 4/5 · Major: India's attempt to destroy the launcher drives the climax and the book's argument about sovereignty.
There is no precedent, and the real disputes so far are legal and diplomatic. Mexico announced plans to ban solar geoengineering experiments after Make Sunsets launched balloons from its territory, calling it a matter of sovereignty, and the EPA has pursued the same company by regulation. Force becomes plausible only if a large programme with visible regional effects exists, which depends on TSHOCK-1. The range is wide, and the event may never occur. 456
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TSHOCK-3
Vulnerable low-lying and small states form a coalition to push for solar geoengineering.
Weight 3/5 · Supporting: the pro-geoengineering coalition around the Queen shapes the politics, though the plot turns on Schmidt.
The most exposed countries have so far mostly opposed it. At the 2024 UN Environment Assembly, Vanuatu, Fiji, Colombia, Mexico and Pakistan were among those supporting non-use, and African environment ministers had called for a global non-use mechanism in 2023. A pro-deployment coalition of at-risk states may still form if warming worsens, but the current alignment runs the other way, so we mark the claim as diverged in its book form. 789
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TSHOCK-4
India and China contest their disputed Himalayan frontier with hand-to-hand fighting rather than firearms.
Weight 2/5 · Texture: the border fights build Laks's arc but are separate from the geoengineering plot.
Under agreements from 1996 and 2005, troops near the Line of Actual Control do not fire guns, and in the Galwan Valley clash of June 2020 soldiers fought with clubs, rods and stones. India later allowed commanders to authorise firearms in extraordinary circumstances. The book's organised volunteer fights are a fiction; the restraint is real but now weaker. 1011
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TSHOCK-5
Stratospheric sulfur injection is cheap enough that a single wealthy backer or small group of states could pay for it.
Weight 4/5 · Major: the plot only works if one rich man can afford to act alone.
A 2018 study put the first 15 years of an aircraft-based programme at about $2.25 billion a year on average, which a handful of governments or very rich people could afford. No purpose-built high-altitude aircraft exists yet, and the same study judged that existing aircraft could not do the job. Stardust expects governments to pay it over $1 billion a year. The cost is not the main barrier. Aircraft, particles and permission are. 1213
- FOR As EPA Rolls Back Regulations for Large Industrial Polluters, It Finds a New Target: A Two-Person Geoengineering Startup. Inside Climate News, 2025-04-18. Make Sunsets says it has launched 147 sulfur dioxide balloons since February 2023 and sold 128,000 cooling credits.
- FOR Global cooling startup raises $60M to test sun-reflecting technology. E&E News, 2025-10-24. Stardust Solutions raises $60 million, $75 million in total, and plans aircraft-based particle experiments.
- AGAINST How one controversial startup hopes to cool the planet. MIT Technology Review, 2025-12-10. Stardust says it will not run outdoor particle tests without government approval, and no international framework exists.
- CONTEXT Mexico plans to ban solar geoengineering after rogue experiment. Climate Home News, 2023-01-18. A government treats a small private balloon launch as a violation of national sovereignty and responds with a ban.
- CONTEXT EPA Seeks Information from Make Sunsets. US Environmental Protection Agency, 2025-04-15. A regulator uses Clean Air Act powers to demand information from the balloon start-up.
- AGAINST How one controversial startup hopes to cool the planet. MIT Technology Review, 2025-12-10. Disputes so far run through regulation and lobbying, and researchers call for a global agreement before any deployment.
- AGAINST UN-Science Summit: Countries Call for the Non-Use of Solar Geoengineering. Heinrich Böll Stiftung, 2024-10-29. Reports Global South governments backing a non-use agreement.
- AGAINST African Countries Call for the Non-Use of Solar Geoengineering in UN Environment Assembly. Solar Geoengineering Non-Use Agreement, 2024. African states ask for a non-use mechanism; an advocacy source for non-use, so read as one side.
- CONTEXT Harvard shuts down geoengineering experiment. E&E News, 2024-03-19. Even the small SCoPEx test ended without a field flight after opposition from environmentalists and Indigenous residents.
- FOR Why Did Soldiers Use Clubs and Stones, Rather Than Guns, to Fight at the Himalayan Border?. Vice, 2020-06-18. Explains why the June 2020 clash was fought without firearms.
- AGAINST Ladakh clash: Indian soldiers allowed to use firearms along LAC in 'extraordinary circumstances'. Scroll.in, 2020-06-22. India loosens its rules of engagement after the clash, weakening the no-firearms norm.
- FOR Stratospheric aerosol injection tactics and costs in the first 15 years of deployment. Belfer Center, Harvard Kennedy School, 2018-11-28. Estimates average costs of about $2.25 billion a year and about 4,000 flights in year one.
- CONTEXT How one controversial startup hopes to cool the planet. MIT Technology Review, 2025-12-10. Stardust expects governments to pay over $1 billion a year for its service.
Ledger updated 5 Nov 2026. All works on the P(n) Board · Method