The U.S. National Academies of Science, Engineering, and Medicine have recently recommended an expansive federal research effort into climate engineering techniques. These proposed interventions, like creating a layer of microscopic droplets in the upper atmosphere or brightening low clouds over the ocean, aim to reduce solar radiation arriving at Earth’s surface. While only a temporary means of addressing climate change, these strategies could prevent some of the worst effects of climate change while more permanent methods, like reducing greenhouse gas emissions, are ramped up.
Through the past few decades of research, mostly with climate models, we are starting to gain an understanding of the benefits and risks of climate engineering. Climate engineering cannot perfectly cancel the climate effects of greenhouse gases. For many climate aspects (like temperature, rainfall and sea ice), climate engineering does a good job of offsetting climate change in most places, but not all. There would also likely be many serious sociopolitical risks, such as geopolitical negotiations about ideal climates or transboundary harms (real or perceived) and compensation for them. These risks need to be carefully studied and weighed so that decision-makers can decide whether and how climate engineering should be used as part of the overall response to climate change.
Despite researchers’ acknowledgment of these risks and the need to proceed cautiously, some have voiced total opposition to even conducting research on climate engineering. Climate engineering experts have been accused of looking for ways to prolong society’s use of fossil fuels or being guided by a “paternalistic form of humanitarianism” while aiming to suppress any other systemic solution to climate change. These arguments have undertones that climate engineering research and the pursuit of equitable systemic changes are mutually exclusive. We argue that such claims are wrong.