New York - The number of people displaced by natural disasters quadrupled from 1970-2013 largely due to urbanisation, and the trend will be aggravated by climate change, a report released on Wednesday found.
The report by the Norwegian Refugee Council's Internal Displacement Monitoring Centre (IDMC) said 22 million people were displaced by disasters in 2013.
While all countries are affected by disasters, 85% of displacement takes place in developing nations where disaster reduction efforts have not kept up with the rate of urbanisation and population growth, according to the report.
In developing countries, rapid urbanisation has often lead to the creation of densely populated shantytowns whose infrastructure is not resilient enough to stand up against severe weather.
"It is the poorest people who pay the price for natural disasters," said Jan Eliasson, UN deputy secretary general.
In Asia, 19 million people were displaced in 2013 by typhoon Haiyan. In the Philippines alone the storm forced 4.1 million people to flee their homes.
Other developed parts of the world were not immune to natural disasters. In the United States 218 500 people were displaced by tornadoes in the state of Oklahoma.
"Most disasters are as much man-made as they are natural," said Alfredo Zamudio, director of IDMC. "Better urban planning, flood defences and building standards could mitigate much of their impact."
Jan Egeland, secretary general of the Norwegian Refugee Council and former UN humanitarian affairs chief, warned that displacements by disasters have grown in frequency, scale and complexity in past decades.
"It is expected to be aggravated in the future by the impacts of climate change," he said noting that weather patterns will likely become increasingly extreme and unpredictable.
In 2013, the number of people displaced by natural disasters was three times higher than the number of those forced to flee due to conflicts.
However, conflicts and disasters often are connected. Of the 36 countries that had armed conflict in 2013, 33 were also affected by natural disasters.
Egeland said the two factors often create a vicious cycle: maintaining peace is hindered by natural disasters, while insecurity in turn prevents countries from building more resilient infrastructure.
The report, which comes a week before the UN Climate Summit, calls on world leaders to take actions to reduce the risk of displacement in swiftly urbanising areas and help communities adapt to the increasingly unpredictable weather.