300 million delta dwellers vulnerable to cyclones, flooding

More than 300 million people in low-lying river deltas, mostly in poorer nations, are exposed to flooding from tropical storms made more deadly and destructive by global warming, researchers said Tuesday.

One in ten live on floodplains hit by once-a-century cyclones that can generate 350-kilometre (200-mile) per hour winds and up to a metre (40 inches) of rain per day, they reported in Nature Communications.

Warmer oceans and more moisture in the atmosphere mean these powerful storms may become more frequent, including in regions rarely touched by their terrible power in the past.

Densely populated deltas where rivers meet the sea are especially vulnerable to flooding caused by such warm-weather monsters, which crisscross the world’s major oceans in summer and fall.

As the reality of climate change sinks in, policymakers must figure out not only how to slow rising temperatures but also prepare for inevitable climate impacts already in the pipeline.

But up to now, the population of the world’s cyclone-exposed river deltas was not precisely known, making it difficult to plan ahead.

“The big question we are trying to answer is how may people live on river deltas and what is their vulnerability to coast flooding,” lead author Douglas Edmonds, a geomorphologist at Indiana University, told AFP.

To find out, Edmonds and colleagues combed through 2017 data for 2174 deltas across the globe.

They calculated that 339 million people lived within their boundaries, all but 10 million of them in developing and least developed countries. (AFP | Marlowe Hood)