Climate change-related natural disasters will put 1.3 billion people and $158tn (£109.08tn, €139.49tn) of assets at risk by 2020, according to the World Bank. A report published by the Global Facility for Disaster Reduction and Recovery, a division of the bank, which focuses on disaster mitigation, says the extent of the risk is high because the world is not well prepared to tackle the threats.

Urging cities to plan ahead for such disasters, before it is too late, the report highlights that the total damages such disasters had caused in recent decades have greatly increased.

Climate change: Natural disasters will affect 1.3 billion people and $158tn of assets, World Bank says
The annual cost of natural disasters in 136 coastal cities was $6bn in 2010 Reuters

According to the report, the worst is yet to come amid a combination of various factors such as global warming, increasing population and the vulnerability of people packed into slums in low-lying, fast-growing cities which already have huge populations, according to the Guardian.

John Roome, the World Bank group's senior director for climate change, said: "With climate change and rising numbers of people in urban areas rapidly driving up future risks, there's a real danger the world is woefully unprepared for what lies ahead. Unless we change our approach to future planning for cities and coastal areas that takes into account potential disasters, we run the real risk of locking in decisions that will lead to drastic increases in future losses."

The report includes some case studies which show that coastal cities with a dense population are sinking at a time when sea levels are rising. It has also been revealed that the number of deaths and the amount of monetary losses from such disasters always increases with time.

Also, the annual cost of natural disasters in 136 coastal cities alone stood at $6bn in 2010. This is expected to increase to $1tn in 2070.

The report says the population in 14 of the 20 most populated cities in the world, is expected to increase by a minimum 40% between 2015 and 2030. "Many of the largest cities are located in deltas and are highly prone to floods and other hazards, and as these cities grow, an ever greater number of people and more assets are at risk of disaster," the World Bank's disaster mitigation division said.

Francis Ghesquiere, head of the secretariat at the division, added that risk from such disasters could be reduced by implementing the right policies immediately. "By promoting policies that reduce risk and avoiding actions to drive up risk, we can positively influence the risk environment of the future. The drivers of future risk are within the control of decision makers today. They must seize the moment," Ghesquiere added.