Geoengineering the Climate: An Overview

Although geoengineering refers to numerous methods of offsetting climate change, including the removal of greenhouse gases (GHGs) from the atmosphere, it is most commonly applied to an approach known as shortwave radiation management (SRM). Advocates for geoengineering make no claims to its being a comprehensive solution toward climate change, forestalling criticism that it is merely a way to avoid reducing fossil fuel dependence. Instead, they present it as a means by which to slow warming and prevent dangerous anthropogenic interference, while exploring the commercial potential of low-carbon energy alternatives, or as an option to turn to in case of a climate emergency, such as a catastrophically rapid rise in sea levels resulting from the unforeseen breakdown of an ice sheet. SRM is accepted as the least expensive method of manipulating the climate after reforestation. It also avoids the land-use issues of reforestation. Furthermore, implementation of SRM could be fairly quick, and could be conducted in a way that rapidly reduces global mean temperature (as opposed to even the fastest conceivable system of emissions reductions). Nevertheless, options for SRM have given rise to a variety of questions regarding morals, technology, and governance, discussed in this article.