“If Europe thinks they have a problem with migration today, wait 20 years.” This was the recent warning from Brigadier General Stephen Cheney, a retired member of the US Marine Corps.

Cheney was referring to the tens of millions of people who are likely to be forced from their homes by climate change and the consequent rise in extreme weather events. As well as becoming more frequent, experts predict extreme weather patterns will become much more violent too.

“See what happens when climate change drives people out of Africa – the Sahel especially – and we’re talking now not just one or two million, but 10 or 20 [million]. They are not going to South Africa, they are going across the Mediterranean,” Cheney said. 

Extreme weather events are increasing

A report by the Environmental Justice Foundation (EJF) says an average of 21.7 million people have been forced from their homes by extreme weather-related events every year since 2008. That equates to 41 people every minute.

Over the past 20 years, 63% of these events, including heatwaves, hurricanes and drought, were made more likely or more severe by human-caused climate change. That is according to data compiled by environmental organization Carbon Brief, which analyzed over 140 peer-reviewed articles relating to extreme weather events and climate change.

And, of those who are forced from their homes, the prospect of ever being able to return home is highly unlikely – with the situation predicted to worsen.

The worry of rising sea-levels

The World Bank’s internal climate migration report estimates that by 2050, 143 million people from across sub-Saharan Africa, South Asia, and Latin America could be internally displaced.

The report, which focuses on slow-onset climate impacts such as crop failure and sea-level rise, considers three potential climate and development scenarios.

The “more climate-friendly” scenario, which predicts the lowest impact, says between 31 million and 72 million people could be forced from their homes across the three regions.

The “more inclusive development” scenario puts internal displacement at between 65 million and 105 million.

While the World Bank report concedes climate migration is inevitable, it also argues the migration process can be successful if supported by good development policies and targeted investments.

For example - Bangladesh, which could have over 13 million internal climate migrants by 2050 - is developing a Perspective Plan for 2041, which factors in climate change as a driver of future migration. The plan recognizes migration as a viable option for people living in the most vulnerable areas, the World Bank says.

Alongside strong action to limit global warming to below 2C by the end of this century, the report also calls on countries and national agencies to embed climate migration into development plans.

“National agencies need to integrate climate migration into all facets of policy. The engagement of private actors, civil society, and international organizations is key to building policy frameworks and capacity,” the report says.

A global problem in need of global policy

The regions outlined by the World Bank represent 55% of the world’s developing population. However, millions more climate refugees could soon emerge from some of the world’s more prosperous nations. 

Last year, former US national security advisor Richard Clark said climate changed posed the greatest single risk to California – with rising seas potentially displacing millions of people.

Residents in the US state of Louisiana are all too familiar with the destruction violent weather events can cause. In 2005 there was widespread devastation as Hurricane Katrina tore across parts of the state. As a result, state authorities devised the 2017 Coastal Master Plan aimed at providing support for internally displaced citizens.

The plan is essentially a list of projects designed to repair and recreate coastline and barrier islands to help maintain land and reduce risk to communities.

Steve Trent, executive director at the EJF, says tackling the issue of climate change displacement must be handled by the global community, and calls for a new legally binding, multilateral agreement on the issue.

 “We cannot hope to deal with the wave of suffering and disruption as single nations; it will not work. We will all be better served, better prepared and better protected if we act together,” Trent says.