Rising temperature, driven by climate change, is increasing the atmosphere's 'thirst', making droughts around the world 40 per cent more severe over the past 40 years, according to a new study.

Researchers, including those at the University of California-Santa Barbara, US, explained that the atmosphere is becoming warmer, thereby increasing its capacity to hold moisture -- atmospheric evaporative demand -- and making droughts more severe, even in places where rainfall has stayed the same.

"Drought is based on the difference between water supply (from precipitation) and atmospheric water demand. Including the latter reveals substantial increases in drought as the atmosphere warms," Chris Funk, director of the Climate Hazards Center at the University of California-Santa Barbara, said.