Climate change is likely to worsen floods on rivers such as the Ganges, the Nile and the Amazon this century while a few, including the now-inundated Danube, may become less prone, a Japanese-led scientific study said on Sunday.
The findings will go some way to help countries prepare for deluges that have killed thousands of people worldwide and caused tens of billions of dollars in damage every year in the past decade, experts wrote in the journal Nature Climate Change.
Overall, a "large increase" in flood frequency is expected in south-east Asia, central Africa and much of South America this century, the experts in Japan and Britain wrote.
Severe floods would happen more often on most of the 29 rivers reviewed in detail, including the Yangtze, Mekong and Ganges in Asia, the Niger, the Congo and the Nile in Africa, the Amazon and the Parana in Latin America and the Rhine in Europe.
Flooding would become less frequent in a handful of river basins including the Mississippi in the United States, the Euphrates in the Middle East and the Danube in Europe.
The experts predicted that northwestern Europe, where the Rhine flows, would be damper while a band from the Mediterranean Sea through eastern Europe - including the Danube region - into Russia would be drier.
A 2012 report about extreme events by a U.N. panel of scientists said there was only "low confidence" in projections of changes in river flooding because of many uncertainties.
Worldwide, average surface temperatures have risen by 0.8 degree Celsius (1.4 F) since the Industrial Revolution, a trend the U.N. panel of experts blames mainly on human emissions of greenhouse gases from cars, factories and power plants.