Summary/Abstract
Climate engineering is the deliberate, large-scale intervention in one or more Earth systems for the purpose of counteracting the causes or symptoms of human-caused climate change. It is also called geoengineering or, less often, climate intervention (CE). CE encompasses two very different kinds of proposed technologies: Solar geoengineering, also known as solar radiation management (SRM), would aim to cool the Earth by reflecting a small fraction of incoming sunlight back into space before it can warm the Earth. Carbon dioxide removal (CDR), sometimes called negative emissions technologies (NETs) or greenhouse gas removal technologies, would remove carbon dioxide (CO2) or other greenhouse gases from the atmosphere and sequester them for long periods of time in biological, geological, or oceanic reservoirs. These two kinds of technologies generally raise different sets of technical, ethical, social, and legal concerns, leading to frequent calls to treat them separately. Since many of the reports being summarized here address both kinds of CE, this report does so as well by surveying and synthesizing the body of literature addressing the governance of climate engineering.