ISLAMABAD >> The U.S. and other countries must recognize the threat represented by the massive floods that hit Pakistan earlier this year and increase preparation for a growing number of natural disasters caused by climate change, a new report said Monday.

It is estimated that as many as 200 million people will be displaced by natural disasters and climate change around the world by 2050, said the report by Washington, D.C.-based Refugees International. The world’s poorest and most crisis-prone countries will be disproportionately affected.

“The massive flooding in Pakistan is a wake-up call that starkly highlights the real threats we face from climate-related disasters,” said Michel Gabaudan, president of Refugees International. “Given the high costs of responding to these catastrophic events, it is in our best interest to plan now for the massive human displacement they cause and protect those most at risk.”

This summer’s floods in Pakistan submerged one-fifth of the country, an area the size of Louisiana, and affected more than 20 million people. The disaster caught both the Pakistani government and the humanitarian community by surprise and overwhelmed their response capabilities.

Many experts believe the floods were the result of climate change, said the report. Others believe the science is uncertain, it said, but most agree that natural disasters are occurring more frequently and that the international community is ill-equipped to respond.

“The floods in Pakistan provide an opportunity to draw lessons and address some of the underlying factors that rendered so many people vulnerable to begin with,” said Alice Thomas, co-author of the report and Climate Displacement Program Manager for Refugees International. “With some foresight and critical thinking, we can implement effective programs to prevent long-term displacement and get people back on their feet more quickly after a disaster occurs.”

The organization called on the United States, which is the largest donor to Pakistan, to prepare a report on how its assistance will address climate vulnerability in the country.

“The failure to address the threat of climate displacement could undermine the long-term stability of countries likely to experience increased floods, storms, droughts and other disasters,” said Gabaudan, the Refugees International chief. “Taking preventive steps now will strengthen these countries and provide support to the world’s poorest people.”