Climate change is real, it's here already and it could impact Florida worse than any other state in the country.

That's the message a panel of experts assembled Wednesday by the nonprofit ReThink Energy Florida took away from the Fourth National Climate Assessment released Friday by the Trump administration.

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The Sunshine State faces numerous threats from climate change, including increased coastal flooding, red tide, toxic blue-green algae blooms, hurricane intensity and mosquito-borne diseases.

The 1,600-page report compiled by 13 federal agencies emphasizes the economic impact of climate change. In a worst-case scenario, the study says climate change could cause a 10 percent reduction in the country's gross domestic product by the end of the century.

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"Agriculture, tourism and fisheries will be the most vulnerable," said Andrea Dutton, associate professor of geology at the University of Florida and an expert on rising sea levels, "and those are all industries we have in spades here in Florida."

Flooding more common

The state's numerous large cities in low coastal areas will be particularly susceptible to sea level rise; and making matters worse, the rate of sea level rise in Florida will be 20 percent higher than the global average, Dutton said.

As the sea level continues to rise and accelerate, Dutton said, normal tides of the future will have the same devastating effects as current hurricane surges.

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In the next decade in South Florida, five-year floods — of such magnitude they occur an average of once every five years — will occur every two months, said Ben Kirtman, an atmospheric sciences professor at the University of Miami.

In 2015, several Florida coastal cities — including Miami, Key West and Fernandina Beach — had all-time records of coastal flooding occurrences, according to the report.

Climate change also will cause more toxic algae blooms, said Susan Glickman, Florida director of the Southern Alliance for Clean Energy, because both blue-green algae, which periodically turns the St. Lucie River guacamole-green, and red tide, which persistently plagues the Gulf Coast, thrive in warm water.

The only hint of a silver lining to the otherwise scary report: Numerous weather models predict drier summers by the middle of the century in southern Florida.

Particularly wet summers often trigger discharges of excess Lake Okeechobee water to the St. Lucie on the East Coast and the Caloosahatchee River on the Gulf Coast. So drier summers could decrease the number of discharges.

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Public health concern No. 1

Climate change will be "the No. 1 public health concern on the planet and in Florida in the 21st century," said Dr. Todd Sack, a Jacksonville gastroenterologist.

The report cites a Florida Department of Health study stating 590,000 people in South Florida face “extreme” or “high” health risks from sea level rise.

The greatest health threat posed by climate change in Florida "may be the smallest," Sack said: mosquitoes.

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More mosquitoes will be able to survive the ever-warming winters, he said, and they'll spread more diseases such as dengue, West Nile and Zika viruses.

President Donald Trump said Monday he doesn't believe the report's dire economic forecast caused by climate change.

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Dutton said Trump was "pushing aside a mountain of scientific evidence. ... People don't believe in climate change because they don't want to believe it. I don't want to believe it either, because it you believe, you have to accept all the scary parts."

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