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The Big Green Button:

Stratospheric Aerosol Injection As A Geopolitical Dilemma During US – China Great Power Competition

  • Background
  • Approach
  • Vital National Interests
  • Four Policy Scenarios
  • International Security Dilemma
  • Findings
  • Discussion
  • Backup Slides

Agenda

Jeff Nielsen

Operational Planner

jnielsen2013@gmail.com

The views presented here are those of the author and do not necessarily represent those of the US Army or Department of Defense.

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Background – Warming

Accelerated Warming Projection

Source: James Hansen et al., “Global Warming in the Pipeline.” Oxford Open Climate Change, III, no 1, November 02, 2023. Accessed December 21, 2023.

What are the risks? “Who” are the US and China?

National Security Strategy 2022: “potentially existential for all nations.”

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China National Climate Change Adaptation Strategy 2035: a “serious threat […] to the present and future survival and development of mankind.”

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Background – Geopolitical Realism

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Background – An Option

Source: White House Office of Science and Technology Policy. Congressionally Mandated Research Plan and an Initial Research Governance Framework Related to Solar Radiation Management. Washington, DC, June 2023.

 

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In the Literature: Risk vs Risk Decision-making

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Assumptions

  • Geoengineering policy will be driven by realist geopolitics emphasizing US / PRC.
  • SAI will remain the leading geoengineering technology for near-term results.

Scope

  • Scenario impacts rather than probability.

Limitations

  • Focuses on policy decisions, not deployment specifications.
  • Cannot be exhaustive of all options or factors.
  • Does not analyze impacts of small-scale SAI or other geoengineering technology.

This Study: Threat-based Decision-making

SAI

Start Year

SAI Mass

+20 years?

+50 years?

+100 years?

What are the adversary’s start criteria?

How can we effect the criteria?

What are the program goals?

When does the program end?

How does this impact us?

How can we react?

Adversary

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State A Unilateral SAI Impacts onto State B Vital National Interests

Interest

Impact

Protect the Homeland and Citizens

Protect Economic Prosperity

Protect National Way of Life

1. Potential Termination Shock

  • Direct damage via exacerbated climate change.
  • Increased demand to provide security and aid.
  • Indirect damage to national ecosystems and economies.
  • De-synchronization of current climate change policies.
  • State A unilaterally governs risks on State B’s interests.
  • Degrades the legitimacy of multinational institutions to resolve conflict.

2. Environmental Damage

  • Direct environmental damage of unclear nature and scale.
  • Direct damage to national ecosystems and economies.

3. Weaponization

  • Potential, though unlikely, State A gray zone strike capability.
  • Potential for State A covert, indirect weaponization via influencing climate systems.

4. Geopolitical Influence

  • Mitigated climate change impacts.
  • Decreased climate-induced security pressures.
  • Potential to degrade security arrangements if State B attempts and fails to deter State A’s SAI.
  • “Free Rider” benefits worth billions or trillions of dollars.
  • Potential mitigation deterrence and conventional policy disruption.
  • State A technological prestige victory displaces State B’s geopolitical influence.
  • Potential for State A to directly leverage SAI for geopolitical influence.

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Green items are SAI opportunities. Red items are SAI threats.

SAI Impacts on Vital National Interests

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Four Futures

Dyadic Analysis of United States and China SAI Scenarios

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Compete

Cooperate

Deter SAI

1. Both states compete while deterring SAI.

“Great Power Status Quo.”

  • Risk: innate risk of projected climate change impacts.
  • Risk: innate risk of future chaotic SAI competition.
  • Risk: high deterrence threshold compared to unmitigated climate change damage.
  • Risk: mutual mistrust degrades deterrence operations.
  • Opportunity: aligns with status quo competition approaches.

2. Both states cooperate to deter SAI.

“Decarbonization G2.”

  • Risk: innate risk of projected climate change impacts.
  • Risk: innate risk of future chaotic SAI competition.
  • Risk: high deterrence threshold compared to unmitigated climate change damage.
  • Opportunity: combined United States - China power is more likely to deter third party SAI.
  • Opportunity: cooperation could plausibly galvanize and expand conventional mitigation policies.
  • Opportunity: provides a cooperative off-ramp from great power competition within state’s respective political narratives.

Deploy SAI

3. At least one state is competing to deploy SAI.

“Race to the Stratosphere.”

  • Risk: innate SAI costs.
  • Risk: termination shock, environmental damage, and geopolitical impacts.
  • Risk: SAI arms race risks imprudent deployment.
  • Risk: Concurrent SAI creates stratospheric three-body problem.
  • Opportunity: trillions of dollars in cost savings over other policies or unmitigated impacts.
  • Opportunity: State A gains SAI geopolitical influence.
  • Risk: State B failing to deter State A exacerbates prestige victory.

4. Both states cooperate to deploy SAI.

“Aerosol G2.”

  • Risk: innate SAI costs.
  • Risk: termination shock, environmental damage, and geopolitical impacts with excluded states.
  • Opportunity: potential trillions of dollars in cost savings over other policies or unmitigated impacts.
  • Opportunity: combined United States – China power is more likely to reduce innate SAI risks than either alone.
  • Opportunity: provides a cooperative off-ramp from great power competition within respective political narratives.
  • Risk: requires sustained cooperation for unclear decades or centuries of SAI deployment.

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Plausible Transitions

Dyadic Analysis of United States and China SAI Scenarios

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Compete

Cooperate

Deter SAI

1. Both states compete while deterring SAI.

“Great Power Status Quo.”

2. Both states cooperate to deter SAI.

“Decarbonization G2.”

Deploy SAI

3. At least one state is competing to deploy SAI.

“Race to the Stratosphere.”

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Least preferred for both states.

4. Both states cooperate to deploy SAI.

“Aerosol G2.”

Plausible

Plausible

Plausible

Plausible

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Less Plausible Transitions

Dyadic Analysis of United States and China SAI Scenarios

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Compete

Cooperate

Deter SAI

1. Both states compete while deterring SAI.

“Great Power Status Quo.”

2. Both states cooperate to deter SAI.

“Decarbonization G2.”

Deploy SAI

3. At least one state is competing to deploy SAI.

“Race to the Stratosphere.”

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Least preferred for both states

4. Both states cooperate to deploy SAI.

“Aerosol G2.”

Low SSP

Cold Feet

Plausible

Plausible

Plausible

Plausible

Radical Change

Radical Change

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SAI Decision Advantage Security Gap

  • Relative climate resiliency.
  • Delayed impact visibility.
  • Non-permissive legal-political-social environment.
  • Deployment legitimization.
  1. Climate vulnerability.
  2. Impact visibility.
  3. Permissive legal-political-social environment.
  4. Fossil Fuel interests.

Notional

Mid-Century Deployment Decision

Earlier Decision

Later Decision

Earlier in the century.

Later in the century.

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1

2

3

4

1

2

3

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Current Security Plans

Optimistic State A or B SAI policy decision point (less policy time pressure).

SAI Security Gap

Potential State A or State B SAI policy decision point (more policy time pressure).

What does SAI Strategic Surprise Look Like?

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Findings

  1. Expanding current SAI research and conventional mitigation policies supports future deterrence or deployment.
  2. Expanding SAI research supports SAI deterrence by better informing decisionmakers on negative SAI impacts.
  3. Expanding SAI research supports SAI deployment by better informing decisionmakers on optimization strategies and equitable governance.
  4. Expanding conventional climate mitigation supports SAI deterrence by reducing anticipated deployment benefits and delegitimizing deployment necessity.
  5. Expanding conventional climate mitigation support SAI deployment by reducing anticipated program scale and duration, thereby mitigating technical and governance risks.

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  1. SAI research can include geopolitical wargames.
  2. What are cooperation on competition mechanisms?
  3. How does SAI deterrence affect other climate policies?
  4. What are other potential geopolitical climate futures? Ecofascism?

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  1. There is still SAI policy maneuver space.
  2. What are cooperation on competition mechanisms?
  3. How does SAI deterrence affect other climate policies?
  4. What are other potential geopolitical climate futures? Ecofascism?

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Discussion

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Backup Sides

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Information Operations

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US Options

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US Security Organization

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SAI Conventional Deterrence Suitability

Can you economically deter PRC SAI?

No, China already has:

  • Aerosol production capacity.
  • Cargo plane capacity.
  • Stratospheric balloon technology.
  • A Meteorological Control Office.
  • Weather control doctrine, training, and systems.

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Experience

Precedent

Incentive

enables

Can you militarily deter PRC SAI?

No:

  • There is likely no credible threat that exceeds the PRC’s perceived existential threat of climate change.
  • The PRC can perceive military SAI deterrence as not credible due to United States free rider benefits and shared climate interests.

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Crisis of PRC unilateral SAI:

Option A: escalate towards a direct existential threat against the Chinese homeland, risking both armed conflict and increasing climate impacts. Not credible.

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Option B: leverage non-military tools to mitigate other SAI risks while potentially receiving SAI free rider benefits.

Conventional Deterrence

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Joint Force Integrated Deterrence

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Impacts of Failed Chinese SAI on United States Vital National Interests

Impact

Protect and Secure American Citizens

Expand Economic Prosperity

Realize and Defend Democratic Values

Impact 1.

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Failed SAI: Termination Shock

  • Compresses the effects of global warming across the full spectrum of impacts into a faster timeline.
  • Accelerates and exacerbates the existing security impacts of climate change, increasing global demand on US security resources.
  • Potential to accelerate warming severely damaging US economic systems, especially ecosystems.
  • Disrupts existing US adaptation and mitigation strategies across the full spectrum of climate change impacts.
  • China unilaterally governs the acceptability of risks on United States vital national interests.
  • Degrades the legitimacy of multinational institutions.

Impact 2.

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Failed SAI: Cooling Overshoot

  • Potential, though unlikely, to harm American citizens through increased extreme weather events.
  • Exacerbates the existing security impacts of climate change, increasing global demand on US security resources.
  • Potential, though unlikely, to increase extreme cold weather events severely damaging US economic systems, especially ecosystems.
  • Disrupts existing US adaptation and mitigation strategies across the full spectrum of climate change impacts.
  • China unilaterally governs the acceptability of risks on United States vital national interests
  • Degrades the legitimacy of multinational institutions.

Impact 3.

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Failed SAI:

Environmental Damage

  • Directly damages human and animal respiratory health.
  • Directly damages animal and plant health through leeched aerosol chemicals.
  • Potential to severely damage US economic systems, especially terrestrial, maritime, and agricultural ecosystems.

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  • China unilaterally governs the acceptability of risks on United States vital national interests
  • Degrades the legitimacy of multinational institutions.

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Impacts of Successful Chinese SAI on United States Vital National Interests

Impacts

Protect and Secure American Citizens

Expand Economic Prosperity

Realize and Defend Democratic Values

Sustains Impact 1 of Failed SAI, Termination Shock, past program end date.

Sustains Impact 3 of Failed SAI, Environmental Damage

Impact 4.

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Successful SAI:

Weaponization

(Direct or Indirect)

Potential, though unlikely, novel weapon to manipulate frequency and severity of extreme weather events.

  • Potential, though unlikely, to damage US economic and natural systems.
  • Potential for indirect weaponization to preference China’s climate outcomes over other regions.
  • China unilaterally governs climate outcomes on United States vital national interests.
  • Potential, though unlikely, novel weapon proliferation and gray zone strike capability.

Impact 5.

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Successful SAI:

PRC Prestige Victory

  • Positively mitigates climate change direct impacts while providing time for other mitigation policies.
  • Decreases global climate-induced conflict and demand on United States security resources.
  • Decreases legitimacy of United States multilateral security arrangements.
  • US “Free Rider” receiving trillions dollars of cost-savings relative to projected climate change impacts.
  • Crowding-out effect desynchronizes US climate change mitigation and adaptation policies.
  • China unilaterally governs climate outcomes on United States vital national interests, to include indirect weaponization via SAI strategy selection.
  • China benefits from a global prestige victory.
  • Degrades the legitimacy of multinational institutions.

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Non-DIME US Policy Options for Chinese Stratospheric Aerosol Injection

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Option

Suitability

Feasibility

Acceptability

Non-DIME

Implement no policies regarding SAI.

  • Impact 1: sustains.
  • Impact 2: sustains.
  • Impact 3: sustains.
  • Impact 4: sustains.
  • Impact 5: sustains.
  • Requires consistent US inaction policy over 80+ years of current emission pathways.
  • Concedes all SAI governance to actors other than the United States government.

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Information United States Policy Options for Chinese SAI

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Option

Suitability

Feasibility

Acceptability

Information

Expand SAI Research

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedence.
  • Extant ways and means to expand research (NOAA, university system).
  • Benefit: improves future SAI decision-making.
  • Cost: +$500 million recommended by NASEM.
  • Cost: Potential negative public and state perception.

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Shape Positive SAI Perception

  • Impact 1: sustains.
  • Impact 2: sustains.
  • Impact 3: sustains.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedence.
  • Requires sufficient whole-of-government consensus.
  • Benefit: messaging supports SAI.
  • Cost: Opportunity costs of other messaging.

Shape Negative SAI Perception

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: sustains.
  • Impact 5: sustains.
  • Significant US policy precedence.
  • Climate change as an existential threat invalidates information deterrence.
  • Benefit: negative perceptions deter SAI deployment.
  • Cost: Opportunity costs of other messaging.
  • Cost: Deters future US SAI deployment.

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Economic United States Policy Options for Chinese SAI

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Option

Suitability

Feasibility

Acceptability

Economic

Expand global climate change mitigation.

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedence.
  • Mitigates risks of each direct climate impacts, risk of adversary SAI deployment, and requisite mass / duration of any future SAI deployment.
  • US decarbonization investment is vulnerable to be offset by other actors’ increased emissions.
  • Benefit: aligns with existing United States climate change policy.
  • Benefit: aligns with global climate change mitigation agreements.
  • Benefit: mitigates SAI risks by reducing injection scale and duration.
  • Cost: Unclear $ trillions to mitigate climate impacts and therefore deter unilateral SAI.

Expand Chinese climate change adaptation.

Not feasible or acceptable.

  • Impact 1: mitigates.
  • Impact 2: sustains.
  • Impact 3: sustains.
  • Impact 4: mitigates.
  • Impact 5: sustains.
  • Significant US policy precedence.
  • Unknown adaptation requirements relative to SAI impacts.
  • Vulnerable to SAI crowding-out effect, exacerbating potential termination shock.
  • Benefit: avoids direct SAI confrontation.
  • Cost: Unknown cost relative to effective deterrence.

Conduct conventional economic deterrence.

  • Impact 1: sustains.
  • Impact 2: sustains.
  • Impact 3: sustains.
  • Impact 4: sustains.
  • Impact 5: sustains.

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  • Climate change as an existential threat invalidates economic deterrence.
  • Requires sufficient whole-of-government consensus.
  • Cost: $800 billion trade risk.

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Military United States Policy Options for Chinese SAI

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Option

Suitability

Feasibility

Acceptability

Military

Conduct conventional military deterrence.

Not feasible.

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Extant Joint Force conventional ways and means.
  • Climate change as an existential threat in higher emission pathways invalidates military deterrence.
  • Benefit: deters all Chinese SAI impacts.
  • Cost: Incurs escalation risk with more immediate negative impacts to US vital national interests.

Expand Integrated Deterrence for SAI’s unique planning factors.

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Extant Joint Force ways and means to integrate with Unified Action partners.
  • US policy precedent.

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  • Benefit: mitigates all Chinese SAI impacts through deterrence.
  • Cost: Planning investment.

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Diplomatic US Policy Options for Chinese SAI

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Option

Suitability

Feasibility

Acceptability

Diplomatic

Ratify Multilateral

“No First-Strike” Treaty.

Not feasible.

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.

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  • Precedent treaties.
  • States already considering SAI will not ratify the treaty.
  • Climate change as an existential threat invalidates diplomatic deterrence.
  • Benefit: Deters all SAI impacts.
  • Cost: Diplomatic investment.
  • Cost: Prevents future US SAI deployment.

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Deploy SAI multilaterally.

Not feasible.

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  • Impact 1: sustains.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Technically feasible.
  • Increasing climate impacts increase SAI support.
  • Heterogeneous preferences for SAI objectives and risks.
  • Governance challenges for decades or centuries of SAI deployment.

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  • Benefit: mitigates global impacts of climate change on vital national interests.
  • Benefit: manages technological SAI risks through cooperation.
  • Cost: Diplomatic investment.
  • Cost: ~$18 billion per year per -1°C for 20+ years.

Deploy SAI mini-laterally including with China.

  • Impact 1: sustains.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Technically feasible.
  • Increasing climate impacts increase SAI support.
  • Heterogeneous preferences for SAI objectives and risks.
  • Governance challenges for decades or centuries of SAI deployment.

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  • Benefit: mitigates global impacts of climate change on vital national interests.
  • Benefit: manages technological SAI risks through cooperation.
  • Cost: Incurs diplomatic risk from excluded actors, including US allies.
  • Cost: $1-10 billion per year for 20+ years.

Deploy SAI unilaterally.

Not feasible or acceptable.

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  • Impact 1: sustains.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Aligns with current US climate change mitigation policies.
  • Heterogeneous domestic perceptions of SAI.
  • Requires consistent US policy over 20+ years of SAI deployment to avoid termination shock.
  • Benefit: mitigates global impacts of climate change on vital national interests.
  • Potential US prestige victory.
  • Cost: Incurs diplomatic risk from excluded actors, including US allies.
  • Cost: $1-10 billion per year for 20+ years.

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United States SAI Deterrence Options

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Option

Suitability

Feasibility

Acceptability

Information

Expand SAI Research

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedent.
  • Existing ways and means to expand research (NOAA, university system).
  • Benefit: improves future SAI decision-making.
  • Cost: $500 million over 5 years.
  • Cost: Potential negative public and state perception.

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Shape Negative SAI Perception

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: sustains.
  • Impact 5: sustains.
  • Significant US policy precedent.
  • Climate change as an existential threat invalidates information deterrence.
  • Benefit: negative perceptions deter SAI deployment.
  • Cost: Opportunity costs of other messaging.
  • Cost: Deters future US SAI deployment.

Economic

Expand global climate change mitigation.

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedent.
  • Mitigates risks of each direct climate impacts, risk of adversary SAI deployment, and requisite mass / duration of any future SAI deployment.
  • US decarbonization investment is vulnerable to be offset by other actors’ increased emissions.
  • Benefit: aligns with existing United States climate change policy.
  • Benefit: aligns with global climate change mitigation agreements.
  • Benefit: mitigates SAI risks by reducing injection scale and duration.
  • Cost: Unclear $ trillions to mitigate climate impacts and therefore deter unilateral SAI.

Military

Expand Integrated Deterrence for SAI’s unique planning factors.

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Existing Joint Force ways and means to integrate with interagency partners.
  • US policy precedent.
  • Benefit: mitigates all Chinese SAI impacts through integrated deterrence.
  • Cost: Planning investment.

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United States SAI Cooperation Options

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Option

Suitability

Feasibility

Acceptability

Information

Expand SAI Research

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedent.
  • Extant ways and means to expand research (NOAA, university system).
  • Benefit: improves future SAI decision-making.
  • Cost: $500 over 5 years.
  • Cost: Potential negative public and state perception.

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Shape Positive SAI Perception

  • Impact 1: sustains.
  • Impact 2: sustains.
  • Impact 3: sustains.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedent.
  • Requires sufficient whole-of-government consensus.
  • Benefit: messaging supports SAI deployment.
  • Cost: Opportunity costs of other messaging.

Economic

Expand global climate change mitigation.

  • Impact 1: mitigates.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Significant US policy precedent.
  • Mitigates risks of each direct climate impacts, risk of adversary SAI deployment, and requisite mass / duration of any future SAI deployment.
  • US decarbonization investment is vulnerable to be offset by other actors’ increased emissions.
  • Benefit: aligns with existing United States climate change policy.
  • Benefit: aligns with global climate change mitigation agreements.
  • Benefit: mitigates SAI risks by reducing injection scale and duration.
  • Cost: Unclear $ trillions to mitigate climate impacts and therefore deter unilateral SAI.

Diplomatic

Deploy SAI mini-laterally with China.

  • Impact 1: sustains.
  • Impact 2: mitigates.
  • Impact 3: mitigates.
  • Impact 4: mitigates.
  • Impact 5: mitigates.
  • Technically feasible.
  • Increasing climate impacts increase SAI support.
  • Heterogeneous preferences for SAI objectives and risks.
  • Governance challenges for decades or centuries of SAI deployment.
  • Benefit: mitigates global impacts of climate change on vital national interests.
  • Benefit: manages technological SAI risks through cooperation.
  • Cost: Incurs diplomatic risk from excluded actors, including US allies.
  • Cost: $36 billion per year for 20+ years for 2°C cooling.

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Source: IPCC, AR6 Synthesis Report (Cambridge, United Kingdom: Cambridge University Press, 2022), 14-15.

Background (Impacts)

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