Some wonder if we could geoengineer our way out of climate crisis

In this July 24, 2017, file photo, an iceberg floats past Bylot Island in the Canadian Arctic Archipelago.
In this July 24, 2017, file photo, an iceberg floats past Bylot Island in the Canadian Arctic Archipelago.David Goldman/Associated Press

Without stemming rise in emissions, we’re getting ahead of ourselves

Re the Oct. 19 Opinion pieces by David Keith (“The world needs to explore solar geoengineering as a tool to fight climate change”) and Raymond Pierrehumbert (“We’re still very much in the dark about the technology”): Proposed solar geoengineering technologies to cool our warming earth by reflecting incoming sunlight could have greater benefits than harms only in a world that is firmly on a path to dramatically reduce heat-trapping emissions from burning fossil fuels.

Yet but for a pandemic-induced hiatus, global warming emissions have not yet declined.

Debates about accelerating research into solar geoengineering put the cart before the horse. First, we must accelerate our commitments to transition from fossil fuels to clean energy. And we need to develop mechanisms and norms of international cooperation to govern solar geoengineering technologies.


Solar geoengineering is far too globally impactful and risky to be researched and potentially deployed by the United States or other powerful nations, especially without robust international rules and safeguards in place. Such governance structures should be established through an inclusive process with diverse publics and stakeholders that includes climate-vulnerable and historically marginalized communities.

Peter C. Frumhoff


Shuchi Talati

Washington, D.C.

Frumhoff is the director of science and policy at the Union of Concerned Scientists. Talati is a scholar in residence at the Forum for Climate Engineering at American University.

It takes resolve, not quick fixes, to tackle greenhouse gases

Raymond Pierrehumbert warns us that solar geoengineering is “a misguided bid for a quick fix” to the climate crisis “that might hold off the symptoms of global warming without confronting the necessary task of kicking the world’s fossil fuel habit.”

If the spigot is on and the bathtub is overflowing, mopping up is necessary, but it won’t solve the problem. To consider geoengineering while the tap is flowing freely — with no real limits on carbon emissions — is absurd. Not only are technological mop-ups unproven, but they also won’t solve the ongoing buildup of greenhouse gases.


Our minds are good at developing new technologies and carrying out research, but what is needed is willpower. It’s critical that we immediately slow carbon emissions by ending fossil fuel subsidies, oil and gas exploration, and drilling and fracking, and instead invest in renewables and technology for energy efficiency.

Taking on fossil fuel interests is a daunting but critical task. It’s time to turn off the spigot.

Marjorie Lee


Climate models are not true evidence

While the arguments put forward by Raymond Pierrehumbert and David Keith give readers a fairly good idea of the issues involved in the current debate as to whether increased funding should be approved for researching solar geoengineering technologies, there is one major omission in both op-eds: the acknowledgement that the only way to begin to estimate the impact of solar geoengineering on the climate in regions all over the world is to run existing climate change models, of which there are several dozen.

Thus, when Keith talks about “evidence” and scientific findings, he does not make clear that there is no direct evidence for these impacts, only evidence from these very complex climate change models. He also does not make clear that these models do not agree with each other on the likely regional impacts of climate change. Indeed, they do not even agree with each other as to the average global impact on the temperature of climate change assuming the same amount of CO2 emissions.


Given that climate scientists have been working on building better computer-based models to make these calculations for many decades, it is unlikely that there will ever be agreement among climate change scientists as to the likely impacts on various regions of the world from solar geoengineering for many decades, if ever.

The only relevant evidence for these regional impacts can come only from trying solar geoengineering on a large scale, which, based on Pierrehumbert’s arguments, I oppose.

Richard A. Rosen


The writer is a retired theoretical physicist.

We can start in our own state

Perhaps solar geoengineering to reduce the effects of climate change will be more effective than a sacrifice to the sun god. We may need to try, since the obvious solutions to reduce greenhouse gases seem unattainable in our highly educated, liberal blue state. Transportation is the largest greenhouse gas-emitting sector in the state. Recently, the MBTA has planned to reduce mass transit and, for the time being, reject electric buses. MassDOT is unwilling even to consider reducing an eight-lane freeway to six lanes (the Allston Interchange’s “throat”) a decade in the future. A Hail Mary pass of sea salt into the sky may be our best hope.

Lucia Dolan


We have to feel the true cost of fossil fuels

In response to the two geoengineering op-eds: Solar geoengineering puts the cart before the horse. Every effort put toward the cure is an effort not spent on prevention. We can prevent the eventual need to use such geoengineering techniques if we actively call for a pathway to zero emissions now.


The idea of eventually having to use geoengineering is on par with the many young-adult dystopian novels released in the last decade: entertaining in fiction, terrifying in fact. Instead, let’s not even get to the point where they are necessary. Contacting your federal elected officials and encouraging them to cosponsor H.R. 763, the Energy Innovation and Carbon Dividend Act of 2019, is a great use of time now.

We live in a capitalist society, and it only works when the prices of goods and services represent their true cost. H.R. 763 does just that, bringing out the true cost of fossil fuel pollution, and encouraging the market toward less society-damaging energy sources. A call to your representative today could prevent ever needing to use one of these unknowable tools in the future.

Robert Gorman


Doing his part for carbon removal

In the paired opinion pieces on geoengineering, the Globe asks whether we should alter the atmosphere to try to cool the earth. The answer is certainly yes, but the way to alter it is to remove the carbon dioxide we’ve dumped there.

This is already going on at a small scale through various carbon-capture technologies. I myself have purchased certificates representing the removal of 40 tons of carbon dioxide from the atmosphere In addition to reducing emissions as much as possible, we should build up to carbon dioxide removal on a huge scale. The cost of such an endeavor is not clear, but some people estimate around $100 to $200 per ton of carbon dioxide removed. This is quite affordable. For example, the carbon emitted per passenger on a flight from Boston to Los Angeles would cost only about $30 to remove.


Ken Olum