G<scp>EOENGINEERING THE</scp> C<scp>LIMATE</scp>: History and Prospect

TLDR

Geoengineering is defined as intentional large‑scale manipulation of the environment to mitigate anthropogenic climate change, yet the boundary between geoengineering and mitigation remains blurred amid a spectrum of human responses. The authors propose a clear definition separating geoengineering from industrial carbon management and argue for explicit debate on the implications of countervailing measures. The study reviews the historical evolution of climate engineering, recent developments such as low‑mass space‑based albedo‑scattering systems and iron fertilization, and evaluates geoengineering through economic, risk, political, and ethical lenses. The review demonstrates that climate‑engineering proposals have been an integral part of the historical response to climate change.

Abstract

▪ Abstract Geoengineering is the intentional large-scale manipulation of the environment, particularly manipulation that is intended to reduce undesired anthropogenic climate change. The post-war rise of climate and weather modification and the history of U.S. assessments of the CO 2 -climate problem is reviewed. Proposals to engineer the climate are shown to be an integral element of this history. Climate engineering is reviewed with an emphasis on recent developments, including low-mass space-based scattering systems for altering the planetary albedo, simulation of the climate's response to albedo modification, and new findings on iron fertilization in oceanic ecosystems. There is a continuum of human responses to the climate problem that vary in resemblance to hard geoengineering schemes such as space-based mirrors. The distinction between geoengineering and mitigation is therefore fuzzy. A definition is advanced that clarifies the distinction between geoengineering and industrial carbon management. Assessment of geoengineering is reviewed under various framings including economics, risk, politics, and environmental ethics. Finally, arguments are presented for the importance of explicit debate about the implications of countervailing measures such as geoengineering.