In this Climategenn episode we hear two committed voices non different sides of the climate engineering debate, make their cases as to why we should or should not research geoengineering with the intention of deployment to cool the Earth.
Dr Heidi Sevestre is an internationally renowned polar scientist making the case against climate engineering (also known as geoengineering) and Herb Simmens is the founder of an international group called the Healthy Planet Action Coalition (HPAC). Both interviews were recorded at COP29 and reflect entrenched positions on both sides of the debate. There are many more voices and we urgently need to hear them – not least from the vulnerable communities who maybe severely impacted by such cooling schemes.
The last word goes to Professor Diana Ürge-Vorsatz, Vice Chair of the IPCC, where she comments on how climate engineering is moving into the main literature advising the United Nations Framework Convention on Climate Change (UNFCCC).
Thanks for listening. Subscribers can preview the episode recorded during week 2 with Professor Kevin Anderson ahead of its as yet unknown publishing date.
If you have been following the UN Climate Summit and want to go inside the talks, accompanied by countless expert insights, then order my book COPOUT from all online outlets worldwide, in paperback and audio formats.
Dr. Heidi Sevestre’s Thoughts on Climate Engineering (Geoengineering) and Solar Radiation Management (SRM)
Dr Heidi Sevestre’s short biography: Heidi is a prominent glaciologist and Deputy Secretary of the Arctic Monitoring and Assessment Programme (AMAP). Born in 1988 in France, she earned her PhD from the University of Oslo, focusing on glacier dynamics. A member of The Explorers Club, she leads expeditions globally, including to Antarctica and the Himalayas. In 2022, she received the Shackleton Medal for her contributions to polar research. Heidi is dedicated to making climate science accessible and is featured in the National Geographic series “Arctic Ascent”
Overview of Geoengineering:
Geoengineering encompasses many proposed interventions (e.g., 80–90 ideas) targeting climate manipulation.
Most extreme methods, like Solar Radiation Management (SRM) and its subcategory, Stratospheric Aerosol Injection (SAI), pose significant risks.
Potential Dangers of Geoengineering:
Stratospheric aerosol injection could:
Alter rainfall chemistry, increasing acid rain.
Disrupt Asian monsoons, affecting water supplies and agriculture.
Large-scale interventions could devastate ecosystems and biodiversity.
Methods like plastic sheets on glaciers introduce pollutants into critical water sources.
Specific Concerns with SRM and SAI:
Operationally complex, requiring thousands of planes flying continuously for years.
Risks include “termination shock,” a rapid climate shift if operations halt suddenly.
Global implications on agriculture, weather systems, and ocean acidification.
Broader Ethical, Logistical, and Governance Issues:
Geoengineering projects could exacerbate pollution (e.g., noise, Arctic contamination)
Governance challenges include unclear oversight and accountability, especially if private actors pursue geoengineering independently.
Financial and ethical concerns over who pays for potential failures and negative consequences.
Ecosystem-Based Impacts:
Proposed methods like seabed curtains or Arctic ice pumps disrupt sensitive ecosystems.
Modifications to Arctic ice or ocean chemistry could irreparably harm indigenous communities, fisheries, and global climate systems.
Critique of Geoengineering’s Appeal:
Promises of quick fixes may divert attention and resources from effective, proven solutions like decarbonization.
Decarbonization is the most efficient and holistic approach to addressing climate change, benefiting energy security, air quality, and economies.
Calls for Responsible Scientific Engagement:
While some research into geoengineering is valid, it must include comprehensive evaluations of environmental, logistical, and societal impacts.
Researchers should collaborate with indigenous communities and experts to ensure ethical considerations are prioritized.
Need for Global Governance and Regulation:
Urgent need for moratoriums and regulations to prevent rogue geoengineering activities by private actors or uncoordinated national efforts.
International scientific communities must provide clear, evidence-based assessments to inform policy decisions.
Warnings Against False Hope:
Sevestre emphasizes the dangers of presenting geoengineering as a viable immediate solution, as it risks neglecting fundamental systemic changes.
Real solutions lie in renewable energy adoption, nature-based approaches, and robust decarbonization strategies.
The Bigger Picture:
Climate engineering does not address the root causes of climate change.
It could worsen existing issues, from microplastic pollution to ecosystem degradation, while offering limited, short-term benefits.
Herb Simmens’ Case for Geoengineering Research and Potential Deployment
Herb’s short biography [source: ‘Healthy Planet Action Coalition’ (HPAC) website]: Herb has been a city manager, county administrator, chief planner for the state of New Jersey, and on the faculty of two universities. He is the author of A Climate Vocabulary of the Future. He holds degrees from the Wharton School of the University of Pennsylvania and the School of Public and International Affairs of Princeton University, and also studied at the London School of Economics. He lives in Silver Spring, Maryland. Herb is HPAC Co-Founder and Organizational Coordinator.
Core Argument for Geoengineering:
Geoengineering, particularly Solar Radiation Management (SRM) and Stratospheric Aerosol Injection (SAI), should be urgently researched and evaluated.
The goal is to reduce global temperatures and mitigate climate tipping points, buying time for emission reductions and large-scale carbon removal.
Importance of Outdoor Experiments:
Computer models, while useful, are insufficient; controlled outdoor experiments are critical to understanding the risks and benefits of geoengineering.
Research must be regulated and systematic to ensure safety and effectiveness.
Favorable View on SAI:
SAI is inspired by natural phenomena like volcanic eruptions (e.g., Mount Pinatubo in 1991), which temporarily cooled the planet by approximately 1°C.
This method could act as a global “sunscreen,” potentially mitigating temperature rise in a controlled manner.
Balancing Risks and Benefits:
Geoengineering has potential downsides (e.g., ozone layer damage, weather system disruptions), but these risks must be weighed against the dangers of inaction.
Simmens compares geoengineering to chemotherapy: harmful but possibly life-saving in the face of dire circumstances.
Urgency of Action:
With climate tipping points approaching, starting geoengineering research now is essential to allow time for governance, technology development, and deployment.
Simmens stresses that delays could result in irreversible damage to the planet.
Need for Governance:
International frameworks are required to regulate geoengineering research and prevent “rogue” states or private actors from unilateral action.
Bodies like the IPCC and COP should lead these discussions to ensure transparent, ethical decision-making.
Direct Research-to-Deployment Approach:
Research must progress incrementally, starting small and scaling up, to gather data and refine techniques.
Any decision to deploy geoengineering would depend on rigorous research showing that risks are manageable and outweighed by benefits.
Concerns About Fossil Fuel Dependency:
Simmens acknowledges the risk of geoengineering enabling continued reliance on fossil fuels but sees it as a necessary stopgap to prevent immediate climate collapse.
He emphasizes that geoengineering should complement—not replace—emission reductions.
Scenarios for Deployment:
In cases of extreme climate emergencies (e.g., widespread forest fires), geoengineering could provide a temporary solution to mitigate impacts.
Deployment timelines depend on governance and technological readiness but could be accelerated in emergencies.
Ethics and Global Responsibility:
Any geoengineering efforts must consider global equity, ensuring that benefits and risks are fairly distributed.
Mechanisms like compensation for affected regions may need to be developed.
Conclusion:
Geoengineering is not a simple or risk-free solution but may be necessary to avert catastrophic climate outcomes.
The stakes are high, and while the process is complex, ignoring the potential of geoengineering would be irresponsible given current trajectories toward climate collapse.
