“According to the Clausius-Clapeyron equation, a one-degree rise in temperature has the potential to give you a 7 percent increase in the intensity of rainfall,” Fowler said. “The second point is that the [Earth’s] poles are increasing in temperature at two to three times the rate of the equator,” Fowler said. That, she said, “weakens the jet stream of the mid-latitudes, which is basically over Europe. In summer and autumn, the weakening of the jet stream has a knock-on effect causing slower-moving storms. So there’s a double whammy of increasing intensity, but the storm lingers longer too.”