12/14/2014 05:00 EST | Updated 02/12/2015 05:59 EST

Rising sea levels could make Florida residents 'climate refugees'

Florida’s vulnerability to the effects of climate change doesn’t seem at first blush to be a Canadian issue.

But every year, some 3.5 million Canadians travel to the sunshine state. What’s more, about half a million Canadians own property in Florida, much of it at risk from rising sea levels.

A lot of that property, particularly if it’s situated along one of the coveted stretches of Miami’s fabled beaches, could well be worthless and literally underwater in a few decades, says Harold Wanless, the chair of the department of Geological Sciences at the University of Miami.

His word for the future of Miami and much south Florida? Doomed.

The “monster” in climate change, as Wanless sees it, is a warming ocean. Sea levels will rise because water expands as it gets warmer, and oceans are taking up vast amounts of heat produced by global warming.

Warmer water is also driving the accelerated melting of the vast ice sheets covering Greenland and Antarctica.

Wanless says a two-metre rise in sea level by 2100 is likely, but says it’s also plausible it could be as much as five metres by the end of the century, and it will continue rising for centuries after that.

The threat of rising sea levels

As Wanless points out, the last time atmospheric carbon dioxide levels were as high as they are now, sea level was more than 20 metres higher.

That means big trouble for the low-lying state of Florida.

“Only nine percent of Miami-Dade County is greater than 10 feet above sea level,” Wanless told Michael Enright, host of CBC Radio's The Sunday Edition.

“Only three percent of it is greater than 12 feet above sea level at normal high tide. And that, as sea level rises, makes us increasingly vulnerable, not only to inundation and sluggish drainage after rainfall, but also from exponentially accelerating danger from storm surges from hurricanes.”

Half a metre of sea level rise, which Wanless says will probably happen by mid-century, will mean Miami will lose its freshwater resources.

Once the sea level reaches a metre higher, all of South Florida’s infrastructure – roads, sewers, water treatment facilities, electricity, hospitals, schools – “will have to be totally redone.”

Wanless argues that the infrastructure could either become too costly or impossible to adapt, upgrade or replace. He raises the spectre of South Floridians being forced to leave the state like a latter-day version of the Okies who fled the Dust Bowl in the 1930s.

“We will become climate refugees," he says.

'Climate refugees'

It’s the lack of planning or science-informed foresight in South Florida that Wanless finds most befuddling. Residents and governments alike are in denial, he says, about the scope of the problem.

He notes that the Miami waterfront is lined with construction cranes erecting condo towers that may be uninhabitable in a few decades, and there are even plans to build two new nuclear power plants on the coast south of Miami.

His greatest frustration is with state politicians who are either dismissive of climate science or ignore the risk of sea level rise. North Carolina recently passed legislation that makes it illegal to take scientific sea level projections into account when planning for coastal development.

“There are so many dimensions of climate change that we have to plan for, and if we don’t, we’re gonna leave families and businesses in ashes.”

Still, Wanless has not lost hope that action will be taken before it’s too late.

“I’ve heard that humans are not very good at planning for things, but we’re great at fixing things we’ve screwed up, and I hope we realize pretty soon that we’ve screwed up.

“We can win challenging world wars and we can do a lot of things when we get our mind around it. The problem is that we are not facing up to the inconvenience that we have to go through to solve this."

You can hear Michael Enright’s full interview with Harold Wanless on The Sunday Edition at 9 a.m. on Sunday on CBC Radio One.