There is increasing interest in the “giant umbrella” as a complementary method against climate change

It boils down to this: With the Earth reaching the hottest temperatures in history and humans not doing enough to prevent it from warming, a small but growing number of… Astronomers and physicists They suggest a possible solution that could have come straight from the pages of science fiction: The equivalent of a giant beach umbrella floating in outer space.

The idea is to create a giant umbrella to protect us from the sun and send it to a very distant point between the Earth and the sun so that we can… Blocking a very small, but very important, amount of solar radiation sufficient to combat global warming. Scientists have estimated that if just 2% of solar radiation was blocked, this would be enough to cool the planet by 1.5 degrees Celsius and keep Earth within manageable limits.

This idea has been on the sidelines of conversations about climate change solutions for years. But as this gets worse, interest in these solar shields is gaining strength, and more and more researchers are offering some variants. There's even a foundation dedicated to promoting sun shields.

A recent study conducted by the University of Utah was analysed powder To be deployed in deep space, while a team from MIT researches how to create a shield made of “space bubbles”. Last summer, Istvan Chabudi, an astronomer at the University of Hawaii's Institute of Astronomy, published a paper proposing… Installing a large solar shield on a reused asteroid.

For now, some scientists led by Yoram Rosen, professor of physics and director of the Asher Institute for Space Research at the Technion-Israel Institute of Technology, say they are ready. Building a typical canopy And prove that this idea will work.

In order to block the necessary amount of solar radiation, this umbrella must be used It is supposed to have an area of ​​more than 2.5 million square kilometers, approximately the size of ArgentinaRosen noted. He added that a parachute of this size weighs at least 2.5 million tons, which is too heavy to be launched into space. So the project should consider a range of smaller canopies. It won't completely block sunlight, but it will cast a fairly diffuse shadow on the ground, Rosen explained.

The researcher stated that his team is ready to design a prototype of an umbrella with an area of ​​9.2 square meters, and that financing the proposal requires between 10 and 20 million dollars.

The scientist said: “We can say to the world: Look, there is a solution that works, and we must take advantage of it and expand it to the necessary size.”

Supporters of the project claim so The umbrella will not eliminate the need to stop burning oil, gas and coal, Major promoters of climate change. Even if greenhouse gas emissions from fossil fuels were reduced to zero today, there would still be an excess amount of heat-trapping carbon dioxide in the atmosphere.

The Earth's average temperature is about to rise by 1.5 degrees Celsius above the average temperature before the industrial era. According to scientists, this is the point beyond which the chances of severe storms, droughts, heat waves and wildfires increase dramatically, and humans and other species will have difficulty surviving. The planet has already warmed by 1.2 degrees Celsius.

According to supporters of the idea, the canopy would help stabilize the climate while other strategies to mitigate climate change are sought.

“I'm not saying this is the solution, but I think we should all work to find all possible solutions,” said Chabuddy, the astronomer who proposed installing a parachute on an asteroid.

The year was 1989 when James EarlyResearchers from Lawrence Livermore National Laboratory have proposed placing a “parachute in space” near a fixed point between the Earth and the Sun called Lagrange point 1, or L1, about 1.5 million kilometers away, four times the average distance between the Earth and the Moon. . There, the gravitational forces of the Earth and the Sun cancel each other out.

In 2006, Roger Angell, an astronomer at the University of Arizona, submitted his proposal for a deflected parachute to the National Academy of Sciences and later received a grant from the NASA Institute for Advanced Concepts to continue his research. Angell proposed launching billions of very light space probes at L1 using a transparent film and guidance technology that would prevent the devices from falling out of orbit.

“It's like turning a knob to reduce the sunlight, plus you don't have to mess with the weather,” Angel said.

The umbrella idea also has some detractors, including… Susan Burr, a PhD student working at the European Center for Advanced Research and Training in Scientific Computing in France, is focusing her interest on a model of solar radiation modulation. He added that the parachute would be very expensive, and given the speed of global warming, it could not be implemented in time. In addition, a solar storm or rock collision from space could damage the shield and the result would be sudden, rapid heating with catastrophic consequences, Bauer said.

The researcher pointed out that it is better to spend money and time working to reduce greenhouse gas emissions and remove carbon dioxide from the atmosphere, and a small portion of the research was devoted to solar geoengineering ideas that are more feasible and profitable.

But Umbrella advocates claim that reducing greenhouse gas emissions, at this point, will fall short of alleviating climate chaos, that carbon dioxide has been found to be too difficult to eliminate, and that there will be a need to analyze all possible solutions. .

Morgan Goodwin One reason parachutes haven't gained as much attention is because climate scientists have naturally focused on what's happening inside the planet, Earth's atmosphere, rather than in space, said the executive director of the nonprofit Planetary Sunshade Foundation.

But according to Goodwin, falling space launch costs and investments in the industrial space economy have increased the possibilities. The foundation proposes to use raw materials from space and launch L1 parachute ships from the Moon, which would be much less expensive than launching them from Earth.

“We believe that as climate scientists better understand the idea of ​​canopies, they will become a visible part of the discussions,” said Goodwin, who is also senior director of the Sierra Club's Angeles chapter.

model Technion It involves placing light solar sails on a small satellite that is transmitted to L1. His prototype would oscillate between L1 and another balance point, tilting the sail between pointing toward the sun and standing perpendicular to it, moving like a curtain scarf, helping to keep the satellite stable and eliminating the need for a propulsion system. “Rosen pointed out.

This researcher commented that the team is still in the pre-design phase, but could launch a prototype within three years after securing funding. Rosen estimated that the full-sized version would cost several trillion dollars (a bill that “would be borne by the whole world, not just one country,” as he put it), but would lower the Earth's temperature by 1.5 degrees Celsius within two years.

“At the Technion, we are not going to save the planet,” Rosen said. “But we will show that it can be done.”

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