Climate chaos: Megacities face rapidly rising risks of flooding

Urban spaces in the tropical monsoon belt are the most vulnerable

- DAVID FICKLING

Global warming is increasing atmospheric moisture and rainfall volumes.

(REUTERS)

Humanity’s future lies in some of the most vulnerable spots on the planet. We've seen that in stark relief of late. A United Nations report last month concluded that the world’s population is increasingly crowded into a group of often low-lying, middle-income megacities in Asia and Africa.

Jakarta and Dhaka dethroned Tokyo's long-held status as the world's biggest city, with 42 million, 37 million and 33 million people respectively. Mexico City and Sao Paulo were overtaken by Shanghai and Cairo among the global top 10. Bangkok, Delhi, Karachi, Lagos, Luanda and Manila were some of the fastest growing among metropolises of more than 10 million.

Many of these very regions have been hit by a devastating run of floods in recent weeks. The monsoon belt from Southeast Asia to West Africa is a swathe of the globe that’s urbanizing the fastest and also the one where catastrophic rainfall is set to increase most dramatically. Nearly 1,000 people have been killed in a wave of storms that have stretched from Sri Lanka to Vietnam, with more than 442 dead in the north of Indonesia’s Sumatra island and at least 160 fatalities in southern Thailand.