To do this, the country wants to set up cloud brightening operations. This method involves dispersing sea spray into the atmosphere, which then allows for better reflection of solar radiation, thus allowing temperatures to cool. The salt particles will then remain in the atmosphere and condense the moisture, forming highly reflective droplets, which will dissipate more solar energy and reduce the temperature.
To verify the viability of this project, American researchers carried out a study, published in the journal Nature Climate Change. They thus used climate models of the Earth system of climate in 2010 and 2050. These were used to stimulate the impacts of two operations carried out in two locations: in the mid-latitudes near Alaska and in the subtropical regions of California.
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Very relative effectiveness
According to the researchers’ results, the cloud brightening operation is effective, but only under certain conditions. Indeed, according to the 2010 climate simulation, the operation carried out near Alaska would reduce the risk of exposure to dangerous heat by 55%. In the subtropical region, the reduction would only be 16%. However, if the 2050 climate model is applied, the results are much less reassuring. In Alaska, the effect on reducing heat stress would be significantly reduced. And even worse, in subtropical regions, it would be synonymous with an increase in temperatures.
The consequences of these operations would not be limited to the United States since several regions, including Europe, would also be affected. Although the results based on the 2010 model would mean a drop in temperature on the continent, the 2050 model shows that the operation would cause heat waves in Europe.
”This shows that marine cloud brightening can be very effective for the US West Coast if done now, but could be ineffective there in the future and cause heat waves in Europe.”, concluded Jessica Wan, researcher who took part in the study, at the microphone of the Guardian.
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“It’s frightening”
For the researcher, the lack of governance in solar geoengineering is “scary”. “Science and policy must be developed together”, she argued. “We don’t want to find ourselves in a situation where one region is forced to geoengineer to combat what another part of the world has done to respond to droughts and heatwaves.”
