The US government is developing a solar geoengineering research plan

The White House is developing a research plan that would guide and set standards for how scientists study one of the more controversial ways of counteracting climate change: solar geoengineering.

The basic idea is that we might be able to deliberately tweak the climate system in ways that release more heat into space, cooling an otherwise warming planet.

The move, which has not been previously reported on, marks the first federally coordinated US effort of this kind. It could set the stage for more funding and research into the feasibility, benefits, and risks of such interventions. The effort may also contribute to the perception that geoengineering is an appropriate and important area of research as global temperatures rise.

Solar geoengineering encompasses a range of different approaches. The one that's gained the most attention is using planes or balloons to disperse tiny particles in the stratosphere. These would then-in theory-reflect back enough sunlight to ease warming, mimicking the effect of massive volcanic eruptions in the past. Some research groups have also explored whether releasing certain particles could break up cirrus clouds, which trap heat against the Earth, or make low-lying marine clouds more reflective.

The 2022 federal appropriations act, signed by President Biden in March, directs his Office of Science and Technology Policy to develop a cross-agency group to coordinate research on such climate interventions, in partnership with NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Department of Energy.

The measure calls for the group to create a research framework to provide guidance on transparency, engagement, and risk management for publicly funded work in solar geoengineering research." Specifically, it directs NOAA to support the Office of Science and Technology Policy in developing a five-year plan that will, among other things, define research goals for the field, assess the potential hazards of such climate interventions, and evaluate the level of federal investments required to carry out that work.

Geoengineering was long a taboo topic among scientists, and some argue it should remain one. There are questions about potential environmental side effects, and concerns that the impacts will be felt unevenly in different parts of the globe. It's not clear how the world will grapple with tricky questions regarding global governance, including who should make decisions about whether to deploy such powerful tools and what global average temperatures we should aim for. Some feel that geoengineering is too dangerous to ever try or even to investigate, arguing that just talking about the possibility could make the need to address the underlying causes of climate change feel less urgent.

But as the threat of climate change grows and major nations fail to make rapid progress on emissions, more researchers, universities, and nations are seriously exploring the potential effects of these approaches. A handful of prominent scientific groups, in turn, have called for stricter standards to guide that work, more money to do it, or both. That includes the National Academies of Sciences, Engineering, and Medicine, which last year recommended setting up a US solar geoengineering research program with an initial investment of $100 million to $200 million over five years.

Proponents of geoengineering research, while stressing that cutting emissions must remain the highest priority, say we should explore these possibilities because they may meaningfully reduce the dangers of climate change. They note that as heat waves, droughts, famines, wildfires, and other extreme events become more common or severe, these sorts of climate interventions may be among the few means available to rapidly ease widespread human suffering or ecological calamities.

Setting standards

In a statement, the Office of Science and Technology Policy confirmed that it has created an interagency working group, as called for under the federal funding bill. It includes representatives of 10 research and mission agencies, including NOAA, NASA, and the Department of Energy.

The group is soliciting input from groups and individuals, and it has already agreed upon an outline for the five-year plan and begun writing it. It plans to complete a draft by the end of July, which will be reviewed by the Subcommittee on Global Change Research and other federal offices in time to meet the mid-September deadline spelled out in the appropriations act.

It's not clear yet whether the plan will recommend increasing public funding, but it could, especially if the working group hews closely to the National Academies' recommendations. So far, little federal money has gone toward research on this subject.

NOAA has now provided around $22 million to projects related to geoengineering over the last three fiscal years, in accordance with earlier spending bills, as MIT Technology Review first reported. Most went to efforts within the agency, though a number of grants this year were provided to academic groups.

That represents nearly the entirety of US federal funding that is known to have gone to research explicitly related to solar geoengineering to date.

It's standard for federal science bodies, like the National Science Foundation, to review the ethics, impacts, and public disclosures of the research projects it funds. But such a structure has mostly been lacking in solar geoengineering research in the US-in part, again, because the government has funded relatively little work so far.

That vacuum has led researchers to look elsewhere for money and oversight. Harvard's Solar Geoengineering Research Program, which has been working toward a small-scale stratospheric balloon experiment for years, has raised money from the William and Flora Hewlett Foundation, the Alfred P. Sloan Foundation, Bill Gates, and others. The university also set up an independent advisory committee for that experiment, which unexpectedly recommended that the team halt a planned flight in Sweden early last year.

Another active group has been the nonprofit Silver Lining, which has provided research grants to teams at the University of Washington, Cornell, Rutgers, and the National Center for Atmospheric Research. It has raised funds from the venture capital firm Lowercarbon Capital, the Pritzker Innovation Fund, and wealthy individuals.

The National Academies report, published in early 2021, likely offers a preview of key issues the interagency working group is grappling with. The authors stressed that a federal research program should be developed in coordination with other countries, that it should focus on building knowledge rather than aiming at deployment, and that it should represent only a minor part of overall federal climate research efforts.

The report also highlighted the need for a strong set of rules to govern research in this field, such as a code of conduct, a registry for projects, and clear standards for engaging with the public and stakeholders. Those stakeholders include communities in the Global South that could be most affected by climate change or geoengineering interventions, it noted.

The authors added that outdoor experiments that involve releasing substances should be considered only if they promise to provide knowledge or observations that couldn't be achieved through lab work, modeling, or similar means. They also recommended creating a permitting system and conducting assessments of the potential environmental impacts of such work.

Last month, the American Geophysical Union, a prominent group of climate and planetary scientists, also announced it was creating an advisory board to work with other global organizations to develop an ethical framework to guide the research and possible deployment of climate change intervention measures." That included solar geoengineering as well as methods for removing greenhouse gas from the atmosphere.

Establishing the baseline

To date, NOAA has mainly funded modeling, monitoring, and lab research focused on establishing a better understanding of the baseline composition of the atmosphere, using high-altitude balloons, aircraft, and other tools, says Gregory Frost, a supervisory research chemist and program manager for NOAA Earth's Radiation Budget initiative, which oversees these projects.

These efforts can help researchers understand how conditions shift when the atmosphere is altered by natural events that disperse particles, like volcanic eruptions, and may allow them to simulate the impacts of deliberate interventions more precisely. As NOAA puts additional monitoring efforts into place around the world, it could also provide a de facto early warning system in the event that some nation or other actor moves ahead with large-scale geoengineering, Frost says.

Several funded projects are also using models to evaluate the feasibility and potential effects of altering marine-layer clouds. Earlier work has indicated that blowing tiny salt particles toward those coastal clouds could make them more reflective and longer lasting, casting back a significant amount of heat if it were done up and down global coastlines.

Frost stresses that the federal government is not conducting or funding any efforts that involve the release of particles into the environment. He adds that most of the work pulls double duty as basic science that improves our understanding of how the atmosphere works and what effect particles from wildfires, volcanoes, rocket emissions, pollution, dust storms, or other sources play. All of that can improve climate modeling, weather forecasting, and predictions of what would happen if any nations moved ahead with climate interventions.

Greater diversity of ideas'

It's not yet clear what the interagency group's recommendations will be, or who they have consulted or will consult in preparing it.

Shuchi Talati, an expert on geoengineering governance who serves on the Harvard balloon research project's advisory committee, says she hopes that any US research agenda would be developed and implemented in careful coordination with other nations around the world, given the global nature of geoengineering and the potential for varied effects. It's also crucial to ensure that one nation doesn't have excessive or unilateral control over the field, she says.

There is already geoengineering research underway in other nations.

European scientists have explored a variety of potential approaches. The Chinese government has funded modeling efforts at several institutions. And the DECIMALS Fund, operated under the UK-based Degrees Initiative, has given nearly $1 million in grants to help scientists in developing countries model the effects of solar geoengineering.

A specific goal of that program is to help researchers in parts of the world particularly vulnerable to climate change play a greater role in evaluation and discussion" of solar geoengineering. The projects include efforts to assess the potential impact of climate interventions on dust storms in the Middle East, droughts in South Africa, water and food security in Bangladesh, and cholera in South Asia, according to the program's site.

Talati says the US report should also carefully consider the sets of rules that should apply to research and experiments in this field, particularly in terms of how to build meaningful engagement with vulnerable communities and ensure that researchers are being transparent about the work. In addition, the research agenda should draw on the expertise and perspective of a broad array of experts, including not just scientists and technical experts but sociologists, economists, and political scientists, she says.

To achieve legitimacy, the geoengineering field needs to be much larger, more open, and include a greater diversity of ideas in how we consider these types of approaches," she says.