Could a Giant Parasol in Outer Space Help Solve the Climate Crisis?
Interest in sun shields, once a fringe idea, has grown. Now, a team of scientists says it could launch a prototype within a few years.
The Idea of Sun Shields
With Earth at its hottest point in recorded history, scientists are proposing a potential fix for global warming: a giant sunshade in outer space. The idea is to block a small but crucial amount of solar radiation in order to cool the planet. If just under 2 percent of the sun's radiation is blocked, it would be enough to lower the Earth's temperature within manageable climate boundaries.
While sun shades have been considered a fringe idea for years, interest in them has been gaining momentum as the climate crisis worsens. Researchers are exploring different variations of sun shields, including scattering dust deep into space, creating a shield made of 'space bubbles,' and tethering a solar shield to a repurposed asteroid.
Building a Prototype Shade
Scientists led by Yoram Rozen, a physics professor, and the director of the Asher Space Research Institute at Technion-Israel Institute of Technology, are ready to build a prototype shade to demonstrate the feasibility of the idea. The shade would have to be about a million square miles in size, roughly the size of Argentina, but too heavy to launch into space. Therefore, a series of smaller shades would be used to cast slightly diffused shade onto Earth.
Dr. Rozen's team plans to design a prototype shade of 100 square feet and is seeking funding between $10 million and $20 million to fund the demonstration. Their goal is to show that the concept works and can be scaled up to the necessary size.
The Role of Sunshades in Climate Stabilization
Proponents of sunshades emphasize that they would not eliminate the need to reduce greenhouse gas emissions. However, they argue that a sunshade could help stabilize the climate while other mitigation strategies are being pursued. Critics, on the other hand, argue that sunshades would be astronomically expensive, could have unforeseen consequences, and divert attention and resources from more viable and cost-effective climate solutions.
Supporters believe that the falling costs of space launches and investments in the space industry have made sunshades more feasible. The Planetary Sunshade Foundation suggests using raw materials from space and launching solar shade ships from the moon, which would significantly reduce costs. The Technion model involves affixing lightweight solar sails to a small satellite sent to a fixed point between the Earth and the sun. Their goal is to demonstrate that the concept is viable and could be an option to consider in the fight against climate change.
