Exploring the Promise of Direct Climate Intervention  (2022) 

As far back as fifty years ago, some of those critical of environmentalists’ alarms argued that emerging technologies would be the ultimate answer to serious environmental threats. Their position then was “why pay or invest now when we can wait and solve these challenges later.” Arguments for delay seem less convincing in 2022 as threats and crises are increasingly acknowledged.   

The massive challenges of coping with global climate crises might be the most important public policy issue of the twenty-first century. Obtaining a practical overview of climate threats and potentials for climate rehabilitation is not easy though. Despite continuing media coverage, these issues have scientific, economic, political, and moral complexities that can be difficult to grasp.     

I completed an undergraduate degree in engineering and for many years taught senior and graduate courses on business and governmental policies. Based on continuing interest and reading, I assumed that I had a better-than-average understanding of environmental and sustainability issues. What I didn’t have was much knowledge of climate science, including ocean currents, trade winds, magnetic fields, weather patterns, soil chemistry, greenhouse gases, plant and animal biology, solar radiation, earth’s atmospheric, and cloud formations. Most of us know little about these and other climatic influences. This relative ignorance extends to cause-effect relationships between diverse human endeavors and climatic conditions.     

Three fundamental concepts can help though in better understanding research and news coverage about climate change. These are the mitigation, adaptation, and intervention activities being undertaken to combat climate threats. We must find effective methods to mitigate or reduce emissions of carbon dioxide, methane and other greenhouse gases. We must adapt in better ways to the negative impacts of future and already present climate threats. And we must explore and deliberate over potential types of direct climate intervention. All three responses to climate change seem necessary, since any one or two combined can’t significantly reduce dire climate consequences in the future. Even if humankind does attain something close to net zero greenhouse gas emissions by later in this century, grim climate conditions will merely plateau and fall slowly over additional decades or generations.   

Much more has been written and recommended regarding mitigation and adaptation than about direct climate interventions. The 2022 IPCC Report as well as Project Drawdown (https://drawdown.org/) detail many tactics for greenhouse gas mitigation and climate change adaptation. Policies and programs in countries all around the world include many of these recommended activities. Doubts remain, however, whether the speed and global scope for applying these many recommendations will be nearly enough. We’ve had a slow start on mitigation and adaptation responses, and some of the causes for our previous inaction or delays can be expected to persist.   

Under the category of climate interventions, certain approaches are less controversial and already underway. Ground surface modification, or painting/coating buildings and outside objects with white colors or reflective surfaces, is one example. More futuristic technologies are also included within this category. Climate scientists at top private, government and academic organizations have been studying and proposing geoengineering technologies involving solar radiation management. Debate exists concerning the feasibility, implementation timeframe, and eventual effects for each of the specific interventions proposed. 

Stratocumulus cloud brightening or seeding in order to reflect more solar radiation before it reaches earth’s surface is one approach. Cirrus cloud thinning, or spraying higher-atmosphere clouds with certain aerosols that allow reflective energy from the earth and lower clouds to escape, is another potential. A third solar radiation management approach is riskier with a mixed bag of larger positives and negatives. Stratospheric aerosol injection, and not just into clouds, could reduce solar radiation hitting earth surfaces and reduce global temperatures within months of its actual application. This solar radiation management, if it resulted in negative consequences, could be reversed within a short period of time. Mechanisms for the delivery and deployment of chosen aerosols appear to be within reasonable engineering capabilities and do not appear to have huge direct financial costs, relative to some other mitigation and intervention alternatives. 

There are questions and fears concerning stratospheric aerosol injection (SAI). Some of these reservations stem from the notion of allowing any government or private- sector interest to control climate or weather. Despite potentially positive results for most people, what about those regions that could be adversely impacted by the effects of less solar radiation? Not all nations worldwide could be expected to agree on whether, when, or how SAI should be used. With remaining issues for SAI delivery and deployment, there are fears that powerful governments or private interests might rush forward prematurely due to their own emergency needs or other interests. Also, certain environmental advocates worry that solar geoengineering might create a “moral hazard,” or that this technological capability might reduce political and social commitment for still-needed greenhouse gas mitigation activities. These and other concerns have halted or delayed early and limited SAI field experiments.   

The future of solar radiation management is unclear now. These climate intervention approaches, even if fulfilling early promises, are viewed by responsible climate scientists as hardly stand-alone cures for what ails our planet. Be aware, though, that scientists and policymakers are seriously investigating direct climate intervention options for reducing future climate threats. If you have a personal interest in learning more about climate science and climate change mitigation, adaptation, and intervention alternatives, I’d recommend Wake Smith’s 2022 book, Pandora’s Toolbox: The Hopes and Hazards of Climate Intervention.