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geoengineering, greenhouse gases, climate change, carbon-scrubbing technologies


Geoengineering is fraught with problems, but research on three approaches could lead to the greatest climate benefits with the smallest chance of unintentional environmental harm. The authors propose a model for thinking about geoengineering based on the concept of restoration, suggesting the term “atmospheric restoration.” Under this model geoengineering efforts are prioritized based on three principles: to treat the cause of the disease itself, to reduce the chance of harm, and to prioritize activities with the greatest chance of public acceptance.

Based on these principles, the authors propose three forms of geoengineering that could provide the greatest climate benefits with the smallest chance of unintentional harm to the environment. Forest protection and restoration is an opportunity available now. The other two, industrial carbon removal and bioenergy linked to carbon capture and storage, need extensive research to make them effective and to reduce their costs. These options will be cheaper than most forms of geoengineering and will provide many additional benefits, including improved air and water quality, national security, balance of trade, and human health.

Our climate is already changing, and we need to explore at least some kinds of carbon-removal technologies, because energy efficiency and renewables cannot take CO2 out of the air once it’s there. Some scientists increasingly argue that we need to do research on sunshade technologies as a backup plan if climate change starts to accelerate dangerously. This argument has merit. However, the sooner we invest in and make progress on reducing greenhouse gas emissions today and promote ways to restore the atmosphere through carbon-scrubbing technologies in the future, the less likely we are ever to need global sunshades. The principle of atmospheric restoration should guide us in curing climate change outright, not in treating a few of its symptoms.

Library of Congress Subject Headings

Greenhouse gases, Climatic changes, Carbon dioxide mitigation, Engineering geology