In this era of global warming, when there is extreme weather like the recent heavy rains that led to flooding in Paris and other parts of France and Germany, the question inevitably comes up: Did climate change play a role?

Not too long ago, the immediate response from most climate scientists would be that while it is generally accepted that global warming will lead to more rain because warmer air can hold more moisture, it is difficult to attribute any one event to climate change. A more detailed answer, perhaps with a definitive conclusion, would come months or years later in a paper published in a peer-reviewed journal.