Climate change will continue to cause an increase in the intensity of extreme rainfall that can lead to severe flooding, if urgent action is not taken to limit global temperature rise to well below 2 degrees Celsius, compared to pre-industrial levels, warn experts in a study published on Monday.
An international research team including scientists from Newcastle University, the University of East Anglia (UEA), the Tyndall Centre for Climate Change Research and Instituto Nacional de Pesquisas Espaciais (INPE), Sao Paulo, Brazil, analysed over 170 peer-reviewed scientific papers.
Their findings, detailed in the journal ScienceBrief Review, showed that extreme rainfall has increased the risk and magnitude of floods in small and urban catchments in many parts of the world, severely impacting local populations and infrastructure.
There has been an increase in daily extreme rainfall rates globally, and on continental scales through the 20th and early 21st centuries. Global warming is also driving increases in short-duration rainfall extremes in some regions.
Further, the study showed the risk of flash flooding in urban areas has likely increased in recent decades, due to the expanding impermeable landscape, increasing surface runoff, and increased extreme rainfall, while increases are projected to continue.
“Global warming means the atmosphere can hold more moisture and could also change the way storms behave. More intense rainfall extremes coupled with changes in other factors could increase the frequency and severity of flooding in many regions,” said Stephen Blenkinsop from the Newcastle’s School of Engineering.
“Even if action is taken to limit the extent of global warming we will need to improve our understanding of how extreme rainfall and flooding will change in the future in order to adapt our cities and other communities to more frequent or more extreme events,” he added.