Can Our Warming Planet Be Healed? US Researchers Redirect Sunlight In A Groundbreaking Climate Experiment – News18

Under the shroud of secrecy, researchers from the University of Washington conducted a groundbreaking experiment on April 2, to employ the “cloud brightening” technique in combating climate change.

Performed atop a decommissioned aircraft carrier in San Francisco, the experiment involved the release of a mist of salt particles into the atmosphere using a specialised device akin to a snow machine. This project was carried out as part of a covert project known as CAARE (Coastal Atmospheric Aerosol Research and Engagement).

What’s cloud brightening?

The experiment involved enhancing the brightness of clouds to increase their reflectivity, thereby reducing the amount of sun rays absorbed by the Earth’s surface. According to The New York Times, the goal is to temporarily lower temperatures in targeted areas, particularly over oceans where sea temperatures are on the rise.

“Every year that we have new records of climate change, and record temperatures, heat waves, it’s driving the field to look at more alternatives,” Robert Wood, the lead scientist for the team from Washington University, was quoted as saying by NYT. “Even ones that may have once been relatively extreme,” he added.

First Proposed By a British Physicist

This concept of using clouds as a natural mirror to deflect solar radiation was first proposed in 1990 by British physicist John Latham. Latham envisioned a fleet of 1,000 ships traversing the globe, dispersing seawater droplets into the air to manipulate cloud properties and mitigate solar heat absorption. The underlying principle of the “cloud brightening” technique hinges on the scattering of sunlight by tiny aerosol particles suspended in the atmosphere.

By dispersing vast quantities of minuscule saltwater droplets into the air, researchers aim to enhance cloud reflectivity and diminish the amount of solar energy reaching the Earth’s surface. However, the success of such endeavors relies heavily on the precise control of particle size and density. Scientists must meticulously calibrate the aerosol spray to ensure optimal reflectivity, according to the report. Despite the potential promise of cloud brightening as a tool to combat global warming, experts remain cautious about its long-term implications.

Concerns

Concerns persist regarding the unpredictability of climate responses to artificial modifications, with fears of unintended consequences such as shifts in precipitation patterns and disruptions to marine ecosystems. It is believed that organisers of Tuesday’s test maintained tight secrecy over the details, fearing opposition from critics. While the current US government supports research into various climate interventions, including marine cloud brightening, it distanced itself from the California study.

In a statement to NYT, the White House clarified that the US government is not involved in the Solar Radiation Modification (SRM) experiment in Alameda, CA, or any other location. This response came despite the release of a federally mandated report on solar geoengineering last June. Solar geoengineering is an umbrella term that describes methods of reflecting sunlight away from the Earth to cool the atmosphere.

David Santillo, a senior scientist at Greenpeace International, is deeply skeptical of proposals to modify solar radiation. If marine cloud brightening were used at a scale that could cool the planet, the consequences would be hard to predict, or even to measure, he said. “You could well be changing climatic patterns, not just over the sea, but over land as well,” he said. “This is a scary vision of the future that we should try and avoid at all costs.”