Climate Plan B may be necessary or life threatening

What do we do if we do not succeed in achieving the goals of the Paris Agreement, and Reducing global warming to 1.5 degrees? Astronaut, space professor Christer Voglesang and economist John Hasler wrote: “Investing everything in one card, that is, international agreements on climate taxes and emissions cuts, without thinking about Plan B is, in our view, too risky.” Discuss DN In March of last year.

One of B’s ​​plans is to develop large-scale technology solutions, the so-called Geological engineeringWhich could stop global warming in other ways. The question divides the research world. Some agree with Fuglesang and Hassler that we must indeed prepare now for such technology to become necessary. Others say it’s life threatening, as the technology is so uncertain and distracts the focus from the one thing that could really save us: Dramatically cut greenhouse gas emissions.

Many see this technology as a knight in a shining armor invading the world to save the world from disaster. They don’t realize that this at best only has the potential to affect the climate problem a little bit. And if we can influence the problem a little bit, is it really worth starting with this? The big danger with the technology is that it slows down the critical momentum of reducing our emissions to zero, says Raymond Perhambert, professor of physics and chair of the Climate Dynamics Group at the University of Oxford.

The Bird Song and Hasler’s B plan is to send millions of tiny parachutes into space, which will shade the Earth to cool the climate. There are also ideas about affecting clouds so that they become thinner and not retain as much heat, or whiter so that they reflect more sunlight. But the most discussed proposal is to release sulfur dioxide or other substances into the stratosphere to reduce the amount of sunlight that can reach the Earth’s surface. The idea is that Mimic the effect of large volcanic eruptionsSmoke and ash clouds can block the sun and affect the entire Earth’s climate.

This summer is planned A group of researchers from Harvard University, USA Balloon experience in Swedish space base Esrange outside Kiruna, Where they will test equipment that can later be used to emit the particles into the stratosphere. Many researchers, many environmental organizations and also Sami Council She was very critical of the planned experiment. Announced in late March The Swedish space company SSC, which operates Esrange, has announced the cancellation of the test flight.

The criticism is that technology is uncertain, and that we do not know what consequences it might have. Particles in the stratosphere will not only filter the sunlight and make the sky gray. It can also affect climate and weather systems in completely unimaginable ways, with extremely dire consequences for precipitation and vegetation. The heating may stop, but the technology cannot have any impact whatsoever on ocean acidification, which is also a result of our CO2 emissions. In addition, we will have to keep refilling with more particles. Unlike carbon dioxide, sulfur dioxide and similar substances remain for only a few years before they disappear, then the total heating quickly returns at full force.

We only create the conditions for an even greater warming catastrophe if this system fails at some point in the next few centuries. Raymond Perehambert says it’s a situation we really don’t want to get into.

David Keith, A professor of applied physics and head of the Harvard University research group, thinks many of the reports about the experiments in the Swedish media were misleading.

A lot of mistakes happened. We are not testing whether or not sunlight can be reflected, nor are we trying to develop technologies to diffuse materials. This is simply not true. In our view, this could be a relatively small experiment to reduce doubts about how small particles form in the stratosphere, he says.

He is keen to point out that the purpose is not to find alternatives to stem greenhouse gas emissions.

This cannot replace emissions reductions. We still have to reduce our emissions. He says these technologies don’t change that.

Men of Raymond Perehambert He feels so relieved to cancel the balloon experience in Kiruna.

It would have been the first experiment actually performed in the stratosphere that involved technology to release substances. This time, they didn’t release anything. But if they had been allowed to do so, I am sure they would have come back and make more attempts. Then they use this unique Swedish facility, without involving the Sami population or Swedish civil society, and without trying to reconcile it with Sweden’s climate goals. He says this is totally unacceptable.

Erik Keelstrom, professor of climate science at SMHI, agrees.

It’s not about blocking the search. But we need to think about this more carefully, and what it could mean in the long term. This kind of research can be done partially inside the laboratory, if you want to know what happens to the particles when they are released into the atmosphere. With the help of climate models, you can also get an idea of ​​how climate is affected, he says.

The technical and financial possibilities for sending mirrors or umbrellas into space are very remote in the future.

But spreading the material into the stratosphere is technically simple. It’s simple enough to have an effect and create big problems for us. Raymond Perihambert says that getting to the real causes of problems isn’t good enough.

It’s unethical to start working with climate this way. We’re already running a massive greenhouse gas emissions experiment, but we’re not controlling it the same way. I don’t think that would be better, says Eric Keelstrom.

David Keith at Harvard University He still thinks it’s important to research this as a possible solution to the climate crisis.

I don’t think this is the best solution. It’s too early and too stupid to comment on. I am not a supporter of this, and I am not developing this technology. He says I am trying to understand it for the benefit of mankind.

But Raymond Perihambert believes that small experiments can never show what we really need to know.

– We can never pre-calculate in detail what the consequences will be for regional weather systems like monsoons or rainfall in India, for example. A small experiment like the Kiruna experiment cannot answer such questions. We won’t know what the true consequences are until we do so fully.