New research conducted by the University of Michigan (USA) and published in the journalPNAS shows thatsatellite forecasts of the effect of aerosolsin the Earth’s climatesignificantly underestimate its impact.
Aerosols, includingsootand thesulfur dioxideFrom the burning of fossil fuels, they are at the core of “cloud droplets”, the water particles suspended in the air that condense to form rain. Theincrease in the number of aerosol particlescauses an increase in the number of cloud droplets, which results inbrighter clouds that reflect more lightand they have a bigger effect on cooling the planet.
Regarding its cooling effect, scientists offer different scenarios that would raise the average global temperature on the planet’s surface during the next century betweenless than 2 and above 3 degrees Celsius, enough to cause effects considered catastrophic in climate change.
Satellite data, on which these conclusions now cast doubt, have been used to argue that all of these models overestimate the extent to which the planet will warm. “The calculations from the satellites are too small,” explains Joyce Penner, professor of Atmospheric Science. In the NASA-funded study, Penner and his colleagues identified flaws in the techniques that satellite calculations use to find the difference between current cloud droplet concentrations and those that occurred before the industrial revolution. “We found that the use of data provided by satellites to infer how much radiation is reflected today and compare it with the volume reflected in the atmosphere, free of pollution, in the pre-industrial era is very inaccurate.” These conclusions are a step towards creating better models.
“We cannot simply rely on satellite data to tell us the effects of aerosols,” Penner points out. “I think we shoulddevise a strategy that uses the models in conjunction with satellite datato get the best answers and predictions, “he concludes.
