New Delhi, PTI

The longest droughts before the turn of this century could be extended by 10 days than previously predicted by climate models, suggesting that potential hazards to societies and ecosystems could be worse than expected, according to a study.

Researchers from Ghent University, Belgium, said that while climate models predict an increase in dry extremes in various regions across the world, uncertainties in projections pose challenges in implementing adaptation strategies.

For the study, the researchers analysed drought projections by a range of climate models to check for potential biases and then fine-tuned them with historical data of the longest number of dry spells each year between 1998 and 2018.

The authors estimated that the longest droughts in a year predicted by fine-tuned models will be 42-44 per cent longer, on average, compared to those predicted by non-fine-tuned ones under both moderate- and high-emissions scenarios.

"These results imply that by the end of this century, the global mean land-only longest annual dry spell could be 10 days longer than currently expected," they wrote in the study published in the journal Nature.

The researchers also found that the increase predicted in the longest dry spell by the fine-tuned models in North America and southern Africa and Madagascar is roughly twice as large as that predicted by the non-fine-tuned ones.

Further, they said that the decrease predicted by the fine-tuned models in Central-East Asia could be almost three times higher than those predicted by non-fine-tuned models.

The results suggested a higher risk of more frequent rainfall and flooding in some regions, the authors explained.

They said the findings stressed the need for a re-evaluation of drought risks around the world.

The results also highlighted the importance of correcting existing biases in climate models to increase confidence in their projections, they added.