What will climate change mean for Florida?

It’s no mere coincidence that the news of Tampa charting its warmest year on record in 2017 made headlines during the same week that the Bay Area also saw its longest cold snap in nearly a decade.

As snow and ice accumulate throughout northern Florida and the Tampa Bay Area experiences some of its coldest, dampest days since 2010, weather extremes are leading the news in early 2018. 

The seemingly wacky, roller-coaster weather is considered to be evidence that long-predicted climate change is becoming a reality, as seen in stronger hurricanes, hotter summers, and whiter winters. 

By next summer, intense heat and humidity will likely sweep away memories of a cold (and snowy) Florida winter. While the Tampa Bay Area is known as a warm-weather region, it has enjoyed a “hot” reputation for more than a century. Marketing materials from the late 1800s and early 1900s were already showcasing the Tampa Bay area’s sultry summers and balmy winters. 

Yet, flurries and light snow have fallen on Tampa Bay Area streets on various occasions over the last century, and nighttime freezes were once an annual wintertime worry for local farmers, gardeners, and owners of exotic fisheries. While the mercury still dips into the upper 30s and low 40s occasionally in the Tampa area, there now are fewer freezing nights and icicles hanging from local citrus trees. 

While warmer weather might be welcomed by local residents, business owners, and countless tourists, hot temperatures and erratic local weather is prompting important questions about the future. 

Why is Tampa breaking so many long-term hot weather records? Is it a harbinger of warmer times to come in Tampa? Will there be an increasing threat of dangerous storms like Hurricane Irma, which came through the area in September 2017? Will we ever see snow or deep freezes in Tampa again? What other weather changes are in store for Tampa? 

Trying to understand what's going on 

As many weather scientists will say, climate change is an issue that is complex and requires much research to better understand. 

"We do have an understanding on climate change on the general scale, but there is also localized warming or even localized cooling in some regions,” says Jennifer Collins, a University of South Florida (USF) professor who recently co-authored "Florida Weather and Climate: More Than Just Sunshine'' (University Press of Florida, 2017). 

USF Professor Jennifer Collins“People who live in areas that experience colder weather or a really cold day will often say that because it's cold, how can there be any warming? But with global warming, you're still going to have cold weather,” she explains. “One of the hallmarks of global warming is an increase of extremes. You get more extreme hot weather and can also have more extremes on the cold side, too.” That means even in a warming world, we will still experience ice, snow, and blizzards -- maybe even terrible blizzards. 

While Tampa’s last “blizzard” came in 1977, when more than a quarter inch of snow covered the region, blizzards are generally not a concern in Central Florida. But chilly weather, or periods when temperatures drop below 50 degrees, is an annual reality for most of the Tampa Bay Area. Yet, the frequency with which significant winter weather occurs locally is decreasing. 

Before the first week of January 2018, “winter of 2010 was our last major cold-weather event locally,” confirms Collins. But she adds, “again, with climate change, you have extremes, but we can’t attribute any one season or event to climate change.” 

So does that mean fewer freezing nights and chilly days in a single year may actually not be a sign of climate change in Tampa? 

“We have experienced significant freeze impacts every 10 to 20 years,” she observes, noting that major Arctic freeze outbreaks in Florida generally occur depending on cycles that are in part caused by factors such as sea surface temperatures and air pressure over the Atlantic Ocean. 

“On the global scale, the last three consecutive years of 2014, 2015, and 2016 have each been the warmest on record,” Collins adds. The Tampa Bay Area has also experienced above-average temperatures on a fairly regular basis. Overall, temperatures in Florida have been, on a month-over-month basis, above average virtually every month since at least early 2015. Only January 2016 proved the anomaly over the past three years or so. 

In 2017, Tampa experienced the second-warmest September on record, with an average temperature of 83.4 degrees Fahrenheit (1.7 degrees hotter than normal). October 2017 was on track to be the warmest on record for much of the Tampa Bay Area until a significant chill helped even out the average temperature for the month. For Tampa, October 2017 ranked as the eighth-warmest October with an average temperature of 78.2 degrees, or some 2.2 degrees cooler than the all-time hottest October for Tampa, which occurred in 1919. 

While the hottest October in Tampa was recorded nearly a century earlier, it should also be noted that six of the 11 warmest Octobers in the city have all occurred since 2002. Furthermore, the previous three Octobers in Tampa have all ranked among the top 10 warmest. The 10 coolest Octobers on record in Tampa all happened prior to 1990. 

As many longtime Floridians know, warmer autumns can lead to persistently high mosquito populations and infestations of other pests that would normally be sidelined by the colder weather more typical of autumn. Colder weather, along with cooler sea surface temperatures, also spell the end of hurricane season, which begins each year on June 1 and lasts until November 30. So, for Tampa residents, cooler weather means more than a respite from summertime heat and humidity. It’s also the key to staving off many pesky pest issues and thwarting the risk of deadly hurricanes. 

Hurricanes may get stronger, but will residents evacuate? 

Hurricane Irma, which made landfall as a Category 4 storm in South Florida, proved the Tampa Bay Area is vulnerable to major hurricanes. While Central Florida was spared from the 130 mile-per-hour sustained winds that were experienced in parts of South Florida, a major hurricane is likely to one day strike Tampa, as most previously happened in 1921. 

"If a hurricane today took a similar path as the 1921 storm, the effects on the Bay Area would be even more devastating because of the population development here since then,” notes Collins. "We will get another storm like the 1921 hurricane. It's not a matter of if we get it, but when we get it."

Warmer conditions, on land and at sea, could also create more serious hurricanes. “I think we will see more intense storms. [Hurricane] Irma had intense 185-mile-per-hour sustained winds, and it was also a Category 5 storm for three days, making it the longest streak of Category 5 sustained winds in the Atlantic during the post-satellite era,” Collins says. 
“We will see greater overall extremes in weather – longer droughts, longer fire seasons, more intense hurricanes, more rainfall, more floods, stronger blizzards, and so on,” says Brian LaMarre, meteorologist at the National Weather Service (NWS) in Ruskin. “Balancing is key in climate, and with climate change, you have less balance.”
“Again though, we can’t attribute any single storm or hurricane season to climate change directly, we can attribute some of the impacts of the storm to climate change. As we have a warmer climate, this has melted the ice sheets for instance, which has resulted in a rise in the sea level.” In 2016, 83 Degrees Media carried a multi-part series on climate change in the Tampa Bay Area and the effects that are already being observed locally and anticipated by local environmental experts as they expect higher water levels in the years ahead. 

“When storm surge occurs due to the strong winds of a storm, more flooding occurs due to the higher sea level. However, the impact is exacerbated by the fact that we have a larger volume of residents and poor infrastructure in these coastal areas than we did years and decades ago.” 

Miami has already dealt with the effects of rising ocean levels, as was observed in early October 2017 when the city was walloped by floods during a king tide event – when the sea is at its highest point during the year. Floods such as those that hit Miami during the king tide are becoming a more frequent occurrence there, and they’re attributed by many officials as early indicators of terrible things to come as climate change takes its toll on southeast Florida. 

“The other thing we will see with climate change is more flooding. You’ll see higher storm surges, but also more nuisance flooding,” Collins says. She predicts we could see similar problems in the Tampa Bay Area, where extremely high tides have also been flooding local neighborhoods. “There will also be more saltwater intrusion into freshwater areas, and this will have an effect on crops and water supplies. Her advice? “We need to build on higher ground and avoid areas known to flood. We also need to have better preparedness and evacuation plans.” 

Preparing for stronger storms, rising waters

Collins and her team of researchers focus much of their efforts on studying patterns of movement by those whose homes are in the path of possible destruction from tropical weather. Tropical storms unleash dangerous amounts of rain and shoreline flooding, and hurricanes have shown to have a particularly deadly impact on Floridians. Hurricane Irma is connected to the deaths of at least 75 individuals in Florida alone. Other major storms, notably Hurricane Andrew, which hit South Florida in 1992 and inspired a variety of new building codes throughout the state, was linked directly or indirectly to at least 44 deaths in Florida. 

According to the results of a study Collins and her USF team performed in 2016 during the evacuation procedures for Hurricane Matthew, which skirted along Florida’s east coat in October 2016, evacuation behavior sometimes runs counter to expectations. In a survey of evacuees leaving the projected path of Hurricane Matthew, many were leaving from counties or areas that were not under a mandatory or suggested evacuation order, meaning that interstates and highways were congested with cars carrying occupants who were not officially ordered to leave their homes. Meanwhile, many who stayed in their homes were in flood-prone areas that were subject to evacuation orders. The study considered various factors, including the role social connections played in whether or not someone stayed in their home or evacuated, the type of media one used to determine the importance of evacuating, and other matters. 

Conveying the significance of an evacuation order to the general public may be challenging when some individuals took great pains to evacuate for a storm in the past that ultimately didn’t directly affect them. 

“Previous experience plays a large role in how people respond to evacuation orders and prepare for storms. I noticed when I interviewed evacuees from Hurricane Irma that those who were impacted by Hurricane Andrew in 1992 said that they never wanted to experience anything like that again and were getting out of South Florida in advance of Hurricane Irma.” In many other cases, individuals whose homes sit in vulnerable areas, such as along the shore or in low-lying areas near ponds and rivers, don’t even understand the difference between a hurricane watch and a hurricane warning. 

“There’s a disconnect between scientists and the general public and the understanding of terminology,” admits Collins. “Some scientists are not good communicators and others are,” she added. “We have to work on communication between scientists and the public. The public should make sure they are looking at authentic sources – for example, want to know more about hurricanes? Then go to the National Hurricane Center (NHC) website.” 

If tropical weather does become more frequent or more intense, then weather scientists will need to figure out how to motivate more people at risk for experiencing life-changing impacts from a storm – to move away from the storm. As staggering hurricane death tolls and devastating damage figures show, climate change can deliver some tragic consequences. But what happens when people don't, literally or figuratively, get the message? 

Misperceptions of climate change, weather science 

Beyond the general public’s lack of misunderstanding of weather terminology, some people continue to naively or deliberately share false information. It’s perhaps harder now than ever to break through myths, half-truths, and fantasy-like weather concepts that can spread rapidly in social media.  

Take, for example, jet contrails, which some conspiracy theorists call “chem trails” containing dangerous chemicals purposefully left behind by airplanes. Contrails are actually harmless streaks of water vapor created by airplane engines as jets speed through the atmosphere, much like exhaust created by cars on the ground. Yet, rumors about “chem trails” continue to spread online. As Brian LaMarre, the meteorologist in charge at the National Weather Service (NWS) in Ruskin, observes, social media causes uneducated people to have a skewed perception of many things, including severe weather and climate change. 

“There’s a lot of misinformation -- people creating false graphs or taking a single National Weather Service image of a satellite image and spinning it into a completely false or hyped-up story that then gets shared across social media,” LaMarre says. “We saw this with Hurricane Irma -- people calling it a Category 6 hurricane when there’s no such thing as a Category 6 hurricane, or sending out fake hurricane models with ‘spaghetti string’ plots (or “ensembles”) going right to their house.” Weather scientists, he says, don’t create those ensembles willy-nilly, but rather create them only after cycling through dozens, or even hundreds, of model runs and taking into account a variety of data and modeling information. 

“There is some public misconception of weather due to social media, such as in 2015 when we had a rash of waterspouts. People shared photos and videos of all of the waterspouts on social media and they began wondering why we’re having more waterspouts than usual,” LaMarre says. It wasn't a phenomenon of more waterspouts; it was a phenomenon of more photos and videos as more people than ever carrying cell phone cameras and share images.

“I compare meteorologists to doctors -- we are both scientists who are working in imperfect sciences,'' LaMarre says. Doctors provide diagnoses and prognoses -- analogously, we provide analyses and forecasts. People sometimes make up stuff to fill in the blanks based on their own concepts.”

Still, LaMarre, who graduated from Western Connecticut State University in 1994 and has worked for the National Weather Service since then, embraces social media as an important tool for sharing vital weather information and climate news with the public. 

“From what I’ve seen in hurricane season, social media has been an extraordinary asset for us to engage with the public,” he says. “It used to be that we would, say, issue tornado warnings, and hope that people would catch word of them. Now, with smartphones, we can better share messages with the public and receive in virtually real time photographs and videos from the ground of the weather.” 

Finding trends in local experiences

One of the many areas among the weather sciences where LaMarre and his colleagues are working to find more concrete answers is in the climate change arena and what it might mean for people in the Tampa Bay Area and beyond. “There’s a lot thinking on how climate change will affect our weather, whether it’s short-term or long-term changes. Climate is partly determined by long-term trends in meteorology.”
“The primary consideration is that for each degree Fahrenheit in temperature rise, the atmosphere has the potential to hold 4 percent more water vapor,'' says Charles Paxton, co-author of "Florida Weather and Climate: More Than Just Sunshine.'' With more water vapor possible in the atmosphere, the potential for greater amounts of rainfall are in the future.”
Detecting and predicting short- and long-term weather patterns is key. “There are cycles, such as the Arctic oscillation cycle which governed the string of days during the winter of 2010, where we had below-freezing weather in the Bay Area,” he recalled, remarking on a period where several communities in and around Tampa did not get warmer than 50 degrees for several consecutive days. “People [falsely] think that with climate change we can’t get snow or get below freezing. Yet, from the conceptual framework, warmer water increases evaporation rates, which means increased condensation, increased cloud cover, cooler temperatures, more moisture and, in theory, more snow.”

Ultimately, the message LaMarre and so many others in the science community are working hard to get out is that what’s happening in one person’s town -- even if it involves localized trending toward colder weather -- is generally not an indication of what’s happening in the grander scheme. “The earth is huge, and climate change isn’t just about what’s happening locally – it’s global-scale changes.” And on both the local and the global scale, LaMarre says things are heating up. “We’ve been warmer than usual.” 

“We will see greater overall extremes in weather -- longer droughts, longer fire seasons, more intense hurricanes, more rainfall, more floods, stronger blizzards, and so on. These are signals that we look at when talking about climate change,” he says. “Balancing is key in climate, and with climate change, you have less balance.” 

Potentially profound impacts on local interests 

Charles Paxton, Ph.D., who co-authored "Florida Weather and Climate: More Than Just Sunshine,'' recently retired from the National Weather Service after 37 years in public service, including 33 with the NWS and 31 at the Tampa Bay Area bureau. He’s seen many long-term shifts in the local weather, and says many can be attributed to weather cycles. “The changes I’ve seen are somewhat linked to the Atlantic Multidecadal Oscillation,” or a climate cycle affecting North Atlantic Ocean sea surface temperatures as observed over the course of many decades. 

“When I started [working at the Tampa Bay Area National Weather Service office] in 1986, we were in a different pattern. The weather here was different,” he recalls. “We had cooler temperatures and there were at least four major freeze events, including those in 1981, 1983, 1985, and 1989.” The 1980s also marked a relatively drier period for the Tampa Bay region. “We were experiencing more drought-like conditions in 1980-82, 1985, and 1988-89,” Paxton says. “We had several weak tropical storms move through.” [One caveat is Category 3 Hurricane Elena, which sat off the west central Florida Gulf coast for several days in 1985 before making landfall near Biloxi, MS]. 

Paxton, who delivers presentations around the state on climate change and related issues, saw a dramatic shift in weather patterns trending toward wetter, warmer conditions during the 1990s. "The Atlantic Multidecadal Oscillation cycle shifted in 1995 with warmer temperatures over the Atlantic Ocean, and this shifted summer weather patterns to more tropical weather development.” Incidentally, 1995 was when Hurricane Opal devastated the Florida Panhandle area. "We need to also consider changes to the Bermuda High, which, I can add, governs much of our weather in Florida, especially in the summer,’’ Paxton says. “That’s something we need to study more to better understand long-term changes." 

Looking ahead, Florida may be in for more weather-related changes. "Some longer-term models projecting years into the future suggest Florida will be drier, and other models say it will be wetter. It’s really a mixed bag of results,” he concedes. “The primary consideration though is that for each degree Fahrenheit in temperature rise, the atmosphere has the potential to hold 4 percent more water vapor. With more water vapor possible in the atmosphere, the potential for greater amounts of rainfall are in the future.”

Whatever the case may be, long-term weather changes remain a concern in the Tampa Bay Area, whether they’re caused by long-term cycles or climate change. But will public policymakers and elected officials respond appropriately? "There are long-term interests and short-term interests, and sometimes longer-term problems conflict with the short-term interests.” 

Part of the challenge comes in building the political will to make the right moves. “It’s coming to light that we have flooding becoming a greater problem for local jurisdictions,” he says, including the flooding situation in Tarpon Springs. The primary problem in the Tampa Bay region is drainage during rainstorms at higher tides, when the runoff backs up into streets. Here in Tampa, we aren’t as prone as Miami is to king tide issues for a variety of reasons; although over one weekend the effect of the full moon and Hurricane Nate over the Gulf of Mexico increased water levels, causing coastal flooding along the west coast of Florida.”

Severe weather events such as flooding and hurricanes concern researchers such as Dr. Robert Hooker, a professor at the Muma College of Business Center for Supply Chain Management & Sustainability

“When we have changes in weather patterns and events like Hurricane Irma, it has a major impact to the overall well being of tourists and locals.“ He points to the following example: “the supply chain can affect produce and dairy ingredients. So, if somebody sees an advertisement from a restaurant for a specific meal and they can’t get the right ingredients then that may disappoint patrons -- what do we do when this effects customer service?” 

Freezes in the 1980s, plant diseases and other “natural” issues have already pushed most citrus growers out of the Tampa Bay Area. “We’re now bringing back fruit from places such as South and Central America.” 

In addition to agriculture, tourism is another huge market sector in The Sunshine State. “Long-term impacts can take away tourism dollars, and tourism is a major part of our economy. Hurricanes or other forms of bad weather and the perception that their vacations could be ruined could dissuade many people from coming to Florida.” 

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Read more articles by Joshua McMorrow-Hernandez.

Joshua McMorrow-Hernandez is a freelance writer who was born and raised in Tampa. He earned his BA in English from the University of South Florida and spent more than three years as a full-time copywriter for a local internet marketing firm before striking out on his own to write for various blogs and periodicals, including TheFunTimesGuide, CoinValue and COINage magazine. He has also authored local history books, including Images of America: Tampa's Carrollwood and Images of Modern America: Tampa Bay Landmarks and Destinations, which are two titles produced by Arcadia Publishing.