Alameda Officials Halt Testing of Cloud-Brightening Device amid Health Concerns
The city of Alameda, Calif., recently made headlines when officials instructed scientists to halt testing on a device that could potentially be used to artificially cool the planet by making clouds brighter. The experiment, conducted by researchers from the University of Washington, involved spraying tiny sea-salt particles on the flight deck of a decommissioned aircraft carrier, the U.S.S. Hornet, docked in San Francisco Bay.
The goal of the experiment was to reflect planet-warming sunlight back into space by making clouds brighter. This method could potentially help combat global warming by bouncing away more sunlight. The experiment began on April 2 and marked the first time in the United States that such a device was tested outdoors. However, on May 4, the City of Alameda asked the researchers to stop the experiment due to possible health concerns.
City officials stated that they were working with a team of biological and hazardous materials consultants to evaluate the health and environmental safety of the experiment. They were specifically concerned about the chemical compounds in the spray and whether they posed a hazard to humans, animals, or the environment. Despite this, officials mentioned that there was no indication that the previous experiments posed a threat to human health or the environment.
The University of Washington Marine Cloud Brightening Research Program, which is conducting the experiment, released a statement reassuring that the salt particles emitted during the experiment were well below established thresholds for environmental or human health impact. The researchers had informed Alameda officials before the study began and were supportive of the city’s review process.
Sarah Doherty, an atmospheric scientist at the University of Washington, stated that her team voluntarily paused the study when local officials raised concerns. She mentioned that while they were able to gather some useful data during the short period of the experiment, more measurements are needed to draw conclusive results.
The concept of brightening clouds as a method of solar radiation modification has gained attention as a potential strategy to combat climate change. This method, known as solar geoengineering or climate intervention, is based on the Twomey effect, which suggests that large numbers of small droplets reflect more sunlight than small numbers of large droplets. By spraying minuscule aerosols into the sky, the reflective properties of clouds could be altered.
Despite the potential benefits of cloud brightening, there are concerns raised by environmentalists about the distraction it may pose from addressing the root cause of climate change – the continued combustion of fossil fuels. Additionally, there are worries about potential side effects such as changes in ocean circulation patterns, temperatures, and precipitation patterns.
As global greenhouse gas emissions continue to rise, the need for innovative solutions to combat climate change becomes more urgent. Researchers like Dr. Doherty emphasize that cloud brightening research should not be seen as an alternative to reducing emissions but rather as a strategy to buy time until emissions are reduced.
The City Council of Alameda is set to discuss the study on June 4, where they will determine whether to allow the experiment to continue. The outcome of this discussion will shed light on the future of cloud brightening research and its potential role in addressing climate change.