Rising sea levels as a result of global warming threatens inundating 21 major cities, including Mumbai and Karachi, a new report by the WorldWatch institute has revealed.
Other cities in the highly vulnerable risk category include New York, Los Angeles, Tokyo, Bangkok, Jakarta, Buenos Aires, Rio de Janeiro, Shanghai and Cairo, the 'State of the World 2007: Our Urban Future' report said.
Researcher Zoe Chafe said: "Although natural disasters are often presented as rare and unexpected tragedies, the reality is they now occur more frequently, affect more people and cause greater economic damage than ever before".
She said the world was already "seeing hints" of the way climate change would affect cities by amplifying natural hazards, including rising sea levels.
In the last century, oceans rose by between nine and 20 cms, which could increase up to 88 cms by 2100, she said. As such, cities would need to plan ahead to avoid disaster, she added.
"This hinges on awareness, good governance and the empowerment of all those who are at risk," news.com.au quoted Chafe, as saying.