Post #4706

Can we dim the sun to fight climate change? Not without risking weather patterns, scientists suggest Some think it's a no brainer: Scattering microscopic particles of sulfur into Earth's atmosphere would reduce the amount of sunlight that reaches the ground, thereby cooling the planet. Indeed, this cooling might temporarily offset the progressing climate change — but a new study claims this type of intervention is likely to have several more unwanted side effects than previously thought. The concept of geoengineering, or human-induced alteration of the planet's climate, by stratospheric sulfur injections (SAI) is backed by nature's own phenomena. The 1991 eruption of the Philippine stratovolcano Mount Pinatubo injected nearly 20 million tons of sulfur dioxide in the stratosphere, the layer of Earth's atmosphere between altitudes of 7.6 and 31 miles (12 and 50 kilometers). The presence of the sulfur particles in the atmosphere led to a global mean temperature drop of about 1 degree Fahrenheit (0.5 degree Celsius), according to the U.S. Geological Survey. But that cooling, measurable for two years after the eruption, also disrupted the Indian monsoon system, causing a drought across South Asia, according to the new research paper. Plus, although the sulfur aerosol cooled Earth's surface, it warmed the stratosphere, speeding up ozone destruction. "There are a range of things that might happen if you try to do this — and we're arguing that the range of possible outcomes is a lot wider than anybody has appreciated until now," Faye McNeill, an atmospheric chemist and aerosol scientist at Columbia’s Climate School and Columbia Engineering and one of the authors of the paper said in a statement. Researchers are using sophisticated computer models to understand the effects of geoengineering interventions. But McNeill and her colleagues warn that no simulation is perfect and that, in the real world, surprises would be inevitable. Source:Space.com @EverythingScience