Climate News May 2024
On Tuesday April 2nd, researchers at the University of Washington used a decommissioned aircraft carrier in the San Francisco Bay to launch microscopic salt particles into the air in an effort to reflect sunlight away from the Earth. This is part of a new area of research called solar radiation modification. In this specific experiment the researchers aimed to increase the density, and therefore the reflectiveness, of the clouds. This experiment was kept very secretive to avoid public backlash prior to the start of the experiment. The experiment follows the termination of a Harvard University experiment in March which planned to launch small sun-blocking aerosols into part of the sky near Sweden. SCoPEx (stratospheric controlled perturbation experiment) was canceled after encountering opposition from Indigenous groups.
If done consistently and widely enough, experts say that solar radiation modification could cool Earth’s climate but that there are many risks that come with the potentially rewarding technology. If this technology becomes more widespread, the aerosols, which do not last very long in the atmosphere, will have to be consistently sprayed in order to continually reflect sunlight and keep the planet cool. If the spraying, a very difficult and precise task, suddenly stopped and we had not reduced fossil fuel use enough, it would cause a dramatic spike in heat, potentially meaning the end of life on Earth. This is known as a “termination shock” and is a very real threat when it comes to solar radiation.
When an NRC (U.S Nuclear Regulatory Commission) committee was questioned about solar radiation by several U.S. government science and intelligence agencies in 2015 they deemed it “irrational and irresponsible” with too many risks to be worth it. They also stated that, in contrast to this risky proposed solution, capturing and trapping carbon from the atmosphere, another type of geoengineering, was worthy and “almost inevitable.” Many scientists also insist that geoengineering Earth’s atmosphere is not a permanent solution to the climate crisis; we will still need to work very hard to change our energy system in order to keep our planet cool.
Despite criticism and many risks, there are several small startups around the globe aiming to use this technology to cool the planet. As there are currently few laws around geoengineering, these companies are free to launch whatever they want into Earth’s atmosphere. One company has been launching giant balloons filled with a mix of helium and sulfur dioxide which pop in the atmosphere, releasing their contents. This method was developed in 1991 after 20 million tons of sulfur dioxide was launched into the atmosphere during the eruption of Mount Pinatubo in the Philippines, which resulted in Earth’s temperature dropping by 1˚ Fahrenheit.
All in all, many believe that solar radiation modification’s risks outweigh its benefits, and it is therefore not a solution for the climate crisis. Scientists believe humans' priority should be to shift to a new energy system that does not rely on fossil fuels and for us to shift away from a consumer mindset more generally. They also say that other types of geoengineering in different ways such as removing and trapping carbon from the atmosphere may help us undo some of the damage we have done to our atmosphere and is worth continued exploration hand in hand with other solutions.
