The rising levels of atmospheric CO2 pose a significant threat to the earth’s cooling systems, particularly the stratocumulus clouds. These clouds cover about 20% of the subtropical and tropical oceans and reflect between 30 and 60% of the sun’s shortwave radiation, making them one of the most crucial cooling systems on the planet. However, a new study by the California Institute of Technology (Caltech) warns that if the atmospheric CO2 level rises from the current 415 ppm to 1,200 ppm, it would destroy the marine clouds, leading to an increase in sea surface temperature by eight to ten degrees. This increase would cause the overall warming to rise by about eight degrees.
The study shows that the effects of rising CO2 levels and climate change on marine stratocumulus clouds were previously unexplored. The clouds are formed due to local turbulence, which is too small to be captured by global climate models. Therefore, the researchers developed a more precise but spatially limited model to investigate the clouds in detail. The model simulated the effects of rising CO2 levels on the cloud cover, radiation balance, and sea surface temperatures. The study found that if the atmospheric CO2 level exceeds 1,200 ppm, the marine clouds become unstable and disappear, leading to a significant increase in sea surface temperature.
The study highlights a blind spot in previous climate models and reveals a previously unknown tipping point in the climate system. The stratocumulus clouds only form at atmospheric CO2 levels below 300 ppm, making them particularly vulnerable to rising CO2 levels. The researchers warn that if the current trend continues, the atmospheric CO2 level could reach 1,200 ppm in the next century, leading to a catastrophic increase in sea surface temperature and overall warming. The study underscores the urgent need for immediate action to reduce CO2 emissions and prevent irreversible damage to the earth’s cooling systems.
