New Climate Model Assessment Suggests Higher Global Warming Projections
New research indicates that official projections for global warming may significantly underestimate future temperature increases. A team led by Gergana Gyuleva at ETH Zurich suggests that for a given emission trajectory, warming could be 25 percent higher than currently projected. For example, if existing policies lead to a 2.6°C rise by 2100, the new assessment suggests it could be 3.25°C. This conclusion stems from a novel approach to assessing climate models. Previously, models that simulated more warming than observed in the recent past were often discounted. However, Gyuleva's team filtered historical climate records to remove the effect of natural variability, such as the La Niña climate pattern, which can temporarily cool surface temperatures. Additionally, they used satellite measurements of incoming and outgoing short-wave and long-wave radiation, which began in 2001, as a more fundamental measure of global warming. Models that best match these observed radiation trends project much greater warmin... 
