A new study greatly reduces uncertainty in climate change predictions, a move economists say could save the world trillions in adaptations for a hotter future. The study, published in the journal Nature Communications, considers dozens of climate models from different countries that differ in the magnitude of global warming they predict to occur by the end of the century. Warming in these models is caused by emissions of carbon dioxide, or CO2, in the atmosphere. CO2 is a greenhouse gas, which creates a kind of blanket in the atmosphere, trapping heat from Earth's surface and preventing it from radiating into space. "All of the models predict warming when CO2 is doubled. But their predictions vary greatly from each other, from 1.3 to 3 degrees Celsius. And that is a problem," said King-Fai Li, the study's first author and UC Riverside assistant professor of environmental science and statistics. The 2015 Paris Agreement aims to keep future global warming to below 1.5 degrees Celsius to avoid irreversible damage. Climate models predicting 1.3 degrees Celsius warming by the end of the century imply a more relaxed timeline for humanity to reverse climate change. However, the prediction of 3 degrees of warming by other models suggests much more urgent action is needed. "Other studies have found that a rush adoption of immature technology for renewable energy may cause economic harm to the tune of tens of trillions of dollars," said Ka-Kit Tung, the study's corresponding author at the University of Washington. There has also been some argument among prominent climate scientists about whether the latest generation of climate models compiled by the Intergovernmental Panel on Climate Change run too hot, meaning they wonder whether the projected warming is too great. "There's a question about whether these climate models are trustworthy," Li said. All climate models can accurately simulate known historical warming in the past 150... |