Summer in Sarasota is brutal: long, hot days that leave you dripping with sweat, followed by stifling nights that provide little relief. And as the saying goes, it’s not just the heat, it’s the humidity. Florida is the most humid state in the United States, and the farther south you go, the more oppressive it gets.
But if you think it can’t get any worse, think again. Using National Oceanic and Atmospheric Administration data, the City of Sarasota has projected that global warming could raise daily high temperatures by as much as 5.4 degrees Fahrenheit by 2050, while lows may increase by 7.2 degrees. That means we could experience up to 60 more days with highs over 95 degrees every year. (Currently, we have 10 days a year over 95 degrees and 89 over 90 degrees.) And with nighttime temperatures rising at a faster rate than daytime temps, our nights will feel like many days do now. Those new highs, combined with a host of other climate-change effects, could change Sarasota dramatically in just a few decades.
Submerged Beaches and Land
As waters warm and polar ice melts, scientists predict that global sea levels could rise from 9.8 to 32.3 inches by 2050. Locally, those projections are lower. The City of Sarasota estimates that the level of the Gulf will rise somewhere between 3.6 and 21 inches by 2050 (and continue rising after that). A rise in the Gulf of a foot and a half—which many scientists consider a conservative estimate for the end of the century—would submerge many mainland coastal areas, St. Armands Circle and large areas of our barrier islands, including the approaches to the bridges. Much of the Sarasota we know would vanish.
Spiking Power Bills
As temperatures go up, so will air conditioning use, particularly in the summer. Florida Power & Light estimates that the energy needed to cool a home doubles in the summer, and the hardest-hit users will be those with inefficient systems. Fourteen percent of Florida households rely on wall air conditioning units or have no air conditioning at all. The Environmental Protection Agency says the nationwide increase in air conditioning costs will outstrip the savings from less energy used to heat homes.
As the air gets hotter, so do the oceans. More than 93 percent of the additional heat generated by global warming has been absorbed by the seas, and half the heat that’s entered them because of global warming has done so in the last 20 years. By 2050, the average Gulf temperature could be as much as 4 or 5 degrees higher, intensifying hurricanes, which are fueled by warm water. As we reported in our October issue, some leading climate scientists are warning that global warming could create a new breed of monster storms, with winds topping 225 miles per hour and storm surges more than 35 feet high.
Longer Droughts, Stronger Rainstorms
By 2050, precipitation is expected to rise around the world by 5 percent, but the real change will come in how that rain is delivered. Rather than a slow, steady increase in rainfall, we’re likely to see longer droughts, with withered crops and vegetation and increased threat of wildfires, punctuated by intense rainstorms. (Warm air holds more moisture than cooler air, so when it releases that moisture, large amounts of rain result.) Such deluges are already becoming more common. In 2013, almost 30 percent of local rainfall came during one 24-hour period.
The World Health Organization reports that mosquito larvae mature more quickly in warmer climates and grown mosquitos feed more frequently. Changing temperature patterns could also bring invasive species now confined to the Caribbean or South America to our shores. That could lead to more mosquito-borne diseases, but regional differences like precipitation and urban development make precise predictions of what will happen in Sarasota difficult.
Disruptions in Agriculture, Plants and Animals
Freezing temperatures will become rarer across Florida, which might boost agriculture, but hotter summers will require more water for irrigation and could decrease yields and livestock productivity. Less available freshwater and the intrusion of saltwater thanks to higher sea levels are also dangers for Florida growers. And since most plants and animals have adapted to specific climate conditions, changes in temperature, rainfall or oceans and waterways can affect their range and ability to thrive—or even survive.
More Algae and Red Tide
The City of Sarasota expects local water temperatures to increase up to 5 degrees by 2050, and we know toxic blue-green algae prefer warmer waters. They also need carbon dioxide to survive, and the carbon we’re pumping into the air and the Gulf may help algal blooms grow more quickly. Warmer waters will also spur the growth and expand the lifespan of the toxic micro-organism that causes red tide.
Dying Fish and Coral
The oceans absorb a quarter of all the carbon released into the atmosphere, and carbon increases their acidity. Marine life has developed and can survive within a narrow range of oceanic chemistry. Excessively acidic water can dissolve the shells of scallops, clams and oysters, and the exterior of coral. It can also scramble the natural instincts of juvenile fish, making them more vulnerable to predators.
Rising Health Risks
Children and the elderly are especially vulnerable to hotter weather and higher humidity. Warmer air leads to increased ozone levels, which can cause more asthma and other respiratory illnesses. Vibrio bacteria, which can cause infections through raw seafood and open wounds and can even lead to death, will grow more quickly in the Gulf, too.
Hotter temperatures, rising water levels and stronger storms menace roads, water systems and wastewater treatment facilities. The City of Sarasota is assessing the vulnerability of some 200 critical facilities in order to set planning priorities. In Miami Beach, where flooding is now common during high tides and storms, officials estimate that it will cost between $400 million and $500 million just to keep their streets dry as sea levels rise.
What Can You Do?
In the face of such overwhelming forces, it’s easy to feel helpless, but political action can make a difference. Protest against policies that ignore scientific realities and support politicians who acknowledge and will address climate change. Businesses and corporations are also responsive to public pressure, and many are taking enlightened steps. National policies are the most effective, but the State of Florida could do much to prepare for and alleviate rising seas, storms and other results of climate change. Here in Sarasota, municipal governments are taking the problem seriously and welcome citizen involvement and support.
Sources: Centers for Disease Control and Prevention; City of Sarasota; HDR; Environmental Protection Agency; Florida Power & Light; Mote Marine Laboratory & Aquarium; Sarasota Bay Estuary Program; Shafer Consulting; Tampa Bay Estuary Program; University of Miami; University of South Florida; U.S. Energy Information Administration