Monday’s report from the Intergovernmental Panel on Climate Change indicated that among other consequences of global warming, heavy rains fueled by warmer air will increase the number of deadly floods across the planet, a trend that many researchers say is already under way.

The recent flooding disasters in Germany, China and Afghanistan share a characteristic that is on the rise: flash flooding. It isn’t clear whether such individual events can be blamed on climate change, even though generally higher temperatures can cause more moisture to gather in the atmosphere. And other factors like the age of infrastructure and river management can contribute to death tolls from flooding.

But as intense rains have become more common across the globe, these types of rapidly moving and often deadly flood events have increased in number over the past decade, according to Robert Brakenridge, founder and co-director of the Dartmouth Flood Observatory at the University of Colorado. The observatory maintains a database of the largest floods world-wide, including information about their size, duration, causes and effects.

Three of the five deadliest floods so far this year were caused primarily by torrential rain—high intensity storms often lasting a short period of time and a major cause of flash flooding.

Flash flooding occurs within minutes or a few hours of excessive rainfall lasting generally six hours or less, according to the National Weather Service. These types of floods are particularly deadly because they rise quickly, catching people off guard and trapping them in buildings or vehicles.