WILDFIRES tearing across Southern California have forced thousands of residents to evacuate from their homes. Even more people fled ahead of the hurricanes that slammed into Texas and Florida in 2017, jamming highways and filling hotels.

A viral social media post showed a flight-radar picture of people trying to escape Florida and posed a provocative question: What if the adjoining states were countries and didn’t grant escaping migrants refuge?

By the middle of this century, experts estimate that climate change is likely to displace between 150 and 300 million people. If this group formed a country, it would be the fourth-largest in the world, with a population nearly as large as that of the United States.

Yet neither individual countries nor the global community are completely prepared to support a whole new class of “climate migrants”.

As a physician and public health researcher in India, I learned the value of surveillance and early warning systems for managing infectious disease outbreaks. Based on my current research on health impacts of heat waves in developing countries, I believe much needs to be done at the national, regional and global level to deal with climate migrants.

Climate change and drought in Somalia have driven many to become refugees. – AFP

Climate migration is already happening. Every year desertification in Mexico’s drylands forces 700,000 people to relocate. Cyclones have displaced thousands from Tuvalu in the South Pacific and Puerto Rico in the Caribbean. Experts agree that a prolonged drought may have catalysed Syria’s civil war and resulting migration.

Between 2008 and 2015, an average of 26.4 million people per year were displaced by climate- or weather-related disasters, according to the United Nations. And the science of climate change indicates that these trends are likely to get worse.

With each one-degree increase in temperature, the air’s moisture-carrying capacity increases by 7%, ­fueling increasingly severe storms. Sea levels may rise by as much as three feet by the year 2100, submerging coastal areas and inhabited islands.

The Pacific islands are extremely vulnerable, as are more than 410 US cities and others around the globe, including Amsterdam, Hamburg, Lisbon and Mumbai. Rising temperatures could make parts of west Asia inhospitable to human life.

On the same day that Hurricane Irma roared over Florida in September, heavy rains on the other side of the world submerged one-third of Bangladesh and eastern parts of India, killing thousands.

Climate change will affect most everyone on the planet to some degree, but poor people in developing nations will be affected most severely. Extreme weather events and tropical diseases wreak the heaviest damage in these regions. Undernourished people who have few resources and inadequate housing are especially at risk and likely to be displaced. – GULREZ SHAH AZHAR/AP