Intense deluges, like the one that preceded a derailment in Carmont, Scotland, are between 15 and 20 percent more likely in future thanks to the warming environment.
Should the world warm by more than two degrees above pre-industrial levels, the likelihood of such destructive downpours would increase by 30 to 40 percent, experts say.
Rainfall data
More frequent extreme rainfalls will increase the risk of flash floods in urban areas and cause more damage to infrastructure, they add.
Climate scientists from the University's School of GeoSciences and School of Physics and Astronomy and the Met Office examined data from weather radars and climate models to calculate the extent to which global warming changed the intensity, frequency and distribution of rainfall at and near Carmont.
Train derailment
The team discovered that on the morning of 12 August 2020, a huge burst of rainfall lasting for around four hours landed close to the crash site.
This was followed by another severe downpour just one hour prior to the derailment on the Aberdeen to Glasgow line.
Three people were killed, and six were injured.
Climate change
Their analysis concluded that climate change has increased the probability of this type of rainfall by 15 to 20 per cent, increasing to 30 to 40 percent in a world two degrees warmer relative to late pre-industrial times.
Previous research has shown that the earth’s atmosphere and oceans are currently 1 to 1.5 degrees warmer compared to conditions in the late nineteenth century.
A warmer atmosphere holds more water and extreme rain happens when all the water in the atmosphere falls out, researchers say.
Severe weather
The cause of the derailment was gravel washed onto the tracks due to heavy rain and an improperly built drain, which could not cope with the volume of water.
Investigators also highlighted problems with operational procedures in dealing with the effects of the severe weather.
The paper, published in the journal Environmental Research Climate, was funded by the University of Edinburgh and the Met Office Hadley Centre Climate Programme, funded by the UK Department of Science, Innovation and Technology (DSIT).