Bengaluru: The rain that triggered the landslide at Wayanad, leaving over 230 people dead and 100 missing, was made 10 per cent heavier by climate change, a study by the World Weather Attribution (WWA) said.
Ten researchers, including six from India, came together for the study which was reviewed by eight others.
The researchers used a gridded rainfall dataset from the India Meteorological Department and explored 25 models under the three multi-model ensembles: sea surface temperature-driven global circulation high resolution models, global circulation models and regional climate models.
"After combining the results from the observations and findings from the 16 models that passed the validation, we find that a one-in-50-year rainfall event in the current climate has been made 10.8 per cent more intense due to the 1.3 degree Celsius warming since the pre-industrial era," the study said.
The 10.8 per cent intensity had an uncertainty of -3.3 per cent or +27.1 per cent. The figure, the study said, was consistent with the prevailing scientific finding that the atmosphere's moisture holding capacity increases by 7 per cent for every 1 degree Celsius warming.
The researchers said increased intensity of rain which fell on the soils saturated by the monsoon showers led to the slippage of a huge portion of a mountain and the disaster that followed.
Lead author Mariam Zachariah of the Climate Change and the Environment institute, Imperial College London, said the 16 models also hold up for the 2 degree C warmer scenario.
"Climate change has made the event (July 30 rain at landslide region) more likely and will make similar events even more frequent under future warming," she said.
Maja Vahlberg of the Red Cross Red Crescent Climate Centre, The Hague, said the land use change in a highly-landslide region added to the devastation.
"This hazard (landslide) is notoriously difficult to predict, especially at the level of granularity necessary to enable effective early action. Deforestation, construction and quarrying for building materials may have contributed to the increased susceptibility of the slopes to slippages," she said.
Marja said that besides moving away from fossil fuels, the world needs to adapt to the extreme weather events.