Scientists warn of rising sea levels in Fla.

(CBS News) Florida is a battleground state, but there's another fight that President Obama and Mitt Romney are hearing about. More than a hundred scientists and economists signed a letter to both presidential candidates warning about the dangers of rising sea levels in Florida.

The presidential candidates may not be talking about rising sea waters, but South Florida residents are. This week, higher than normal tides flooded Miami's South Beach, swamping streets, people and businesses.

"It has been like a high tide coming in," said one person,"but there's no explanation, it hasn't really been raining."

Top scientists say in the future, climate change will make flooding much worse. They drew up a map to illustrate the expected flood risk along Florida's coastline in 2060. The color red means "underwater".

And Professor Ben Kirtman,of the University of Miami,says the long-term projections look much worse.

"By 2100, when sea level rise has been a full foot, I would say that 10 to 15 million people in Florida would have to be relocated," he said.

That's why Florida's top scientists and environmentalists sent a letter to both presidential candidates asking them to address the issue.

"I think that this is probably the single greatest problem that the world is facing today," said Kirtman. "I'm concerned that partisanship has made it difficult for us to be pragmatic to try to figure out pragmatic solutions."

To fight the rising threat, South Florida government officials have agreed to cooperate on solutions. Kirtman says fixes should include new pumping systems and canals. But planning needs to begin now.

"It takes years to figure out how to do it," he said. "It takes years to build it. It takes years to raise the money to do it. So if you're waiting until sea level rises a foot before you build it, it's too late."

And it's not just the East Coast. Another study says San Francisco's airport could be flooded within decades.