Weather manipulation tools—such as cloud seeding to induce or suppress rain—are not new, but deploying them at scale is becoming easier and more affordable. As the impacts of climate-related changes in weather patterns intensify, the incentives to turn to technological fixes will increase in affected areas. Think of governments trying to manage simultaneous declines in rainfall and increases in water demand.
Aside from the potential environmental consequences, at a time of increasing geopolitical tensions even well-intentioned weather manipulation might be viewed as hostile. Perceptions would be paramount: a neighbouring state might see large-scale cloud-seeding as theft of rain or the reason for a drought. Cloud-seeding planes might be viewed as dual-use tools for espionage. Hostile uses are prohibited, but cannot be ruled out—for example, weather manipulation tools could be used to disrupt a neighbour’s agriculture or military planning. And if states decided unilaterally to use more radical geo-engineering technologies it could trigger dramatic climatic disruptions.
As technologies evolve and deployment increases, increased transparency—about who is using what, and why—would help limit destabilizing ambiguity. So too would active discussion and collaboration on environmental vulnerabilities, both bilaterally between bordering states and on wider regional and global multilateral platforms.
Illustrations by Patrik Svensson