A study reveals that the most advanced climate model, CMIP6, might be significantly underestimating future extreme rainfall in India. This surprising discovery raises urgent questions about our preparedness for climate impacts on regional weather patterns
A new analysis indicates that the latest climate models used by the Intergovernmental Panel on Climate Change (IPCC) might be underestimating the effects of climate change on rainfall in India.
The sixth Coupled Model Intercomparison Project (CMIP6), a set of advanced models designed to simulate atmospheric, land, and oceanic processes, is widely employed to project future climate impacts under various emission scenarios.
While CMIP6 models provide valuable insights on a global scale, they may not accurately reflect regional variations. The study, which focused on the Indian summer monsoon from June to September, involved refining and correcting the CMIP6 projections by adjusting for sea surface temperatures and precipitation. This approach is notable for including sea surface temperature, an important factor for the Indian monsoon, in its downscaling efforts.
The researchers found that the CMIP6 models “strongly underestimate the intensity and spatial distribution of rainfall associated with extreme rainfall events.” Their corrected projections showed a 96 percent improvement in accuracy compared to observed data from the India Meteorological Department for the period 1980 to 2014.
The study revealed that, during the baseline period, 8 percent of India’s land area experienced heavy rainfall linked to extreme events. Projections suggest that between 2030 and 2060, extreme rainfall events could increase by 14 percent under a high emissions scenario, with an 18 percent rise expected between 2060 and 2100.
These findings suggest that CMIP6 models might not fully capture the severity of future extreme rainfall events in India, underscoring the need for more accurate regional climate projections to better understand and address potential impacts.