Researchers studying the effects of global warming on rainstorms have found that warmer air redistributes moisture towards the middle of storms, focusing heavy rain over a smaller land area.

Ashish Sharma of the University of New South Wales in Sydney, Australia, and his colleagues analysed data from 1,300 rain gauges and 1,700 temperature stations across Australia to test how air temperature affects the intensity and spatial organization of storms. They found that atmospheric moisture was more concentrated near the storm centre in warm storms than in cooler ones, resulting in more intense peak precipitation in that area.

Storms that extend over a smaller area but release increasingly intense rainfall in a warming climate might boost local flood risk and severity, the authors conclude.

Geophys. Res. Lett. http://doi.org/bd7s (2016)