Climate engineering carries serious national security risks − countries facing extreme heat may try it anyway, and the world needs to be prepared

• But the world will likely pass that threshold within a decade, and global warming is showing little sign of slowing.
• The world is already facing natural disasters of epic proportions as temperatures rise.
• The only known method able to quickly arrest this temperature rise is climate engineering.
• Both strategies would reflect a small amount of sunlight back to space to cool the planet.

• One of the largest concerns for many countries when it comes to climate change is national security.
• Could climate engineering help reduce the national security risks of climate change, or would it make things worse?

The massive problem of climate change

• Since the industrial revolution, humans have put about 1.74 trillion tons of carbon dioxide into the atmosphere, largely by burning fossil fuels.
• Countries could pull carbon dioxide out of the atmosphere and lock it away, a process called carbon dioxide removal.
• As long as the amount added is larger than the amount removed, droughts, floods, hurricanes, heat waves and sea level rise, among numerous other consequences of climate change, will keep getting worse.

Who might try climate engineering and how?

• Various government research arms are already gaming out scenarios, looking at who might decide to carry out climate engineering and how.
• Climate engineering is expected to be cheap relative to the cost of ending greenhouse gas emissions.
• However, a single country or coalition of countries witnessing the harms of climate change could make a cost and geopolitical calculation and decide to begin climate engineering on its own.

Creating risks for neighbors raises conflict alarm

• So, a climate engineering project in one country is likely to affect temperature and rainfall in neighboring countries.
• Some studies show that a moderate amount of climate engineering would likely have widespread benefits compared with climate change.
• Once climate engineering is deployed, countries may be more likely to blame climate engineering for extreme events such as hurricanes, floods and droughts, regardless of the evidence.
• On top of that, the physical effects of climate engineering depend on who is doing it and what they’re doing.

What’s next?

• It’s hard to say whether climate engineering would create more conflict, or if it could defuse international tensions by reducing climate change.
• At the United Nations Environment Assembly in March 2024, African countries called for a moratorium on climate engineering, urging all precaution.
• Put simply, climate engineering is a technology that can’t be ignored, but more research is needed so policymakers can make informed decisions.

Ben Kravitz receives funding relevant to this work from the National Oceanographic and Atmospheric Administration and the National Science Foundation. Tyler Felgenhauer receives funding relevant to this work from the National Science Foundation and from Resources for the Future.