The 2005 hurricane season produced several powerful storms fueled by abnormally-warm ocean waters. 

Hurricane Wilma – the strongest Atlantic storm ever recorded – was one of four major hurricanes to 

strike Florida that year. For days, this Category 5 cyclone sat off the coast of the Yucatán Peninsula, 

pounding the region with record-setting 185-mph winds. By the time Wilma made landfall over 

Florida, its fierce winds had quelled to 120 mph – still strong enough to topple trees and rip 

off roofs. In total, 62 deaths and $16- to $20-billion in damages were blamed on this storm.

Some scientists predict that intense storms like Wilma – which strengthen over warm 

water – will be more common in the future as a result of rising temperatures. Research 

has documented an unprecedented rise in atmospheric carbon dioxide (CO2) and nearland air and sea surface temperatures. But while hurricanes receive much attention, sea 

level rise is another anticipated consequence of rising temperatures – one that may have 

dramatic ecological impacts on coastal areas worldwide. South Florida, in particular, will be 

affected by sea level rise due to its low elevation and flat landscape. 

 Although it is important to consider the impact of climate change on developed areas, effects of 

this phenomenon on the natural environment also deserve attention. As stewards of some of south 

Florida’s most unique natural areas, Everglades, Biscayne, and Dry Tortugas National Parks and Big Cypress National Preserve play 

an important role in conservation. Together, they protect over 2.4 million acres of habitat and harbor more than 14 endangered 

species. While scientists remain uncertain about how the effects of climate change will manifest, their research suggests that lowlying south Florida and its extraordinary ecosystems are vulnerable. 

Climate Change and

South Florida’s National Parks

...portrait of a changing landscape

Preparing 

for a future with 

climate change 

What are scientists predicting?

How will ecosystems respond?

What is the National Park 

Service doing?

National Park Service

U.S. Department of the Interior

South Florida Natural Resources Center

Everglades National Park 

Image credit: 

October 20, 2005 

NASA image of Hurricane 

Wilma (yellow to red colors 

correspond to sea surface 

temperatures of 82-90oF).
Atmospheric CO2

 concentrations are higher today than in any other period within the last 420,000 years. Scientists have found that 

natural causes alone cannot account for this rapid rise. Instead, 

they believe human activities also are responsible. Deforestation 

and fossil fuel burning, in particular, have caused a 31% increase in 

atmospheric CO2 since 1750. When gases like CO2 build up in the 

atmosphere, they prevent heat from escaping. It’s this greenhouse 

effect that is responsible for the earth’s rising temperatures. 

S e a L e v e l R i s e

The United Nations Intergovernmental Panel on Climate Change 

(IPCC) predicts a 7- to 23-in rise in global sea level in 95 years 

due to the expansion of warming seawater and the contributions 

of melting glaciers. IPCC also notes that sea level rise may exceed 

these predictions if rapid dynamic changes in polar ice flow occur. 

Low-lying coastal regions will be particularly susceptible to inundation. Most of Dry Tortugas and Biscayne National Parks, and 

two-thirds of Everglades National Park, have an elevation lower 

than 3 ft. Yet, even more important than the extent of sea level rise 

may be the rate of rise. For example, mangrove trees – which stabilize sediments – might be able to keep pace with slowly rising sea 

levels by accumulating soil and effectively raising ground elevation. However, if sea level rise is rapid, coastal freshwater habitats 

could be inundated by rising sea water. A June 2006 report by the 

National Wildlife Federation and the Florida Wildlife Federation 

highlighted these potential impacts and suggested that sea level 

rise would harm the world-class recreational fishery in Florida 

Bay for bonefish, yellowtail snapper, permit, redfish, snook, spotted sea trout, and tarpon.

W a r m i n g O c e a n s

According to the IPCC, sea surface temperatures may increase 

2o to 5oF by 2100. While the most obvious impact of such a trend 

could be an increase in hurricane frequency and intensity, a lesser 

known fact is that abnormally-warm water can adversely affect 

coral reefs. In 2005, the same warm waters that triggered Hurricanes Katrina and Wilma badly damaged coral reefs in the eastern 

Caribbean, including coral reefs in the Florida Keys.

For many coral species, several weeks of warm water just 2oF more 

than peak summer temperatures can wreak havoc. When this happens, the symbiotic algae that live within the coral’s cells are ejected, leaving behind the animal’s skeleton. Known as “bleaching,” 

the phenomenon can have severe impacts on the entire marine 

ecosystem. 

P h y s i c a l C h a n g e s . . .

South Florida’s habitat types and coastline in 1995.

Shallow Marshes

The shallow marshes of 

Everglades National Park 

and Big Cypress National 

Preserve provide the only 

existing habitat for the endangered Cape Sable Seaside Sparrow. Sea level rise 

is expected to shrink these 

areas under some model 

scenarios (see maps).

Pinelands

Everglades National Park 

(ENP) contains most of the 

remaining pineland habitat 

in south Florida. Under 

some sea level rise scenarios, 

this small but critical area is 

projected to disappear (see 

maps). Upland species like 

the Wild Turkey and Eastern 

Bluebird would suffer from 

this reduction in habitat.

Beaches

Green sea turtles nest on 

the beaches of Everglades, Biscayne, and 

Dry Tortugas National 

Parks. If these beaches 

erode, valuable sea turtle 

habitat could be lost (see 

maps). 

Dry Tortugas National Park

photo: William Perry, ENP

Everglades National Park

photo: Lori Oberhofer, ENP

Everglades National Park

photo: Vincent DiFrenna, ENP
Biscayne and Dry Tortugas National Parks are home to many of 

south Florida’s most pristine coral reefs. Park managers are working to protect the reefs from those risks over which we have control, including pollution and damage from boat anchoring. Managers believe that this strategy will lead to a healthier reef that will 

better withstand the effects of climate change. A newly established 

Research Natural Area in Dry Tortugas National Park will help ensure the continued existence of this important ecosystem. 

Scientists have also linked high sea surface temperatures to 

seagrass die-offs, and higher sea temperatures could fuel algal 

blooms or promote marine diseases.

H u r r i c a n e s

A sea surface temperature of 80oF or more – combined with favorable humidity and wind conditions – is enough to fuel powerful hurricanes. Some scientists expect that in the future, as ocean 

temperatures continue to rise, hurricanes will be more frequent 

and intense. Others warn that long-term trends analyses can be 

potentially biased because monitoring and detection capabilities 

have improved over time. For example, detection improved substantially with the advent of geostationary satellite imagery in the 

mid-1960s so more storms can be identified now than in the past 

(Eos Transactions, 2007). However, Webster et al. (Science 2005), 

using relatively recent data, found that the number of intense tropical storms has risen by 80% worldwide during the last 35 years. And 

2005 broke records for its numerous powerful hurricanes – four of 

the 28 named storms reached Category 5 strength. Still, since hurricane patterns do fluctuate naturally over multi-decadal periods, 

the authors of the paper indicated that, without additional data, 

they are reluctant to attribute recent trends in hurricane frequency 

and intensity to warming sea water.

Recent climate simulations for this century published by scientists at NOAA and the University of Miami (Geophysical Research 

Letters 2007) illustrate the complexity of the ocean/atmospheric 

system and how difficult it can be to reach generalizable conclusions about the relationship of climate change and hurricanes. For 

example, their work suggests that warming ocean temperatures in 

the tropical Atlantic will alter existing ocean circulation patterns in 

such a way as to increase wind shear – a dominant controlling factor 

in hurricane activity – and thus serve to inhibit hurricane development and intensification in this region. However, their models also 

identify regions, such as the western tropical Pacific, where warming does appear likely to produce conditions which favor hurricane 

development. One thing is certain, when intense hurricanes do occur, storm surge flooding that often accompanies such storms will 

be exacerbated by sea level rise, placing both natural ecosystems 

and man-made facilities at even greater risk. 

. . . a n d E c o l o g i c a l R e s p o n s e s

Projected habitat shifts with 2 ft of sea level rise. Courtesy: Harold 

Wanless, University of Miami. 

Deepwater 

Slough Mangroves

Legend Florida Bay

Sea level rise, coupled with warmer air temperatures, may change Florida Bay’s salinity by 

increasing evaporation and concentrating salt. 

Seagrass beds would be adversely affected by 

such an increase. 

Mangrove Forest

If sea level rises too quickly, 

mangroves, which protect 

shorelines from storm surge, 

may not be able to keep 

pace and this important community could be lost. Mangroves along the southwest 

coast of Everglades National 

Park and in Biscayne National 

Park are projected to shrink 

and shift inland due to sea 

level rise (see maps).

Biscayne National Park

photo: Brett Seymour, ENP

Everglades National Park

photo: Quan Dong, ENP

NPS Boundaries

Shallow

Marsh

Urban

Areas

Pinelands
Managers and scientists working in south Florida’s national parks 

are planning ahead for climate change. They believe that by 

protecting pristine natural areas from pollution and overharvesting; restoring already-damaged ecosystems; 

and improving park facilities, the parks will endure 

despite the added threat of climate change. 

R e s t o r a t i o n

Beginning in the late 1800s, the natural sheetflow of the “River of Grass” was altered to provide flood control 

and water supply to a growing population. Everglades ecosystems 

suffered as a result and restoring the Everglades has since become paramount. The Comprehensive Everglades 

Restoration Plan (CERP) was enacted with 

a goal of reestablishing the natural flow of 

water by removing barriers to flow, such as 

some key canals and levees. This restoration is even more important in the face of 

climate change, since a restored Everglades 

will be healthier and more resilient to climate 

change.

V i s i t o r F a c i l i t i e s

Park officials are taking an adaptive approach to climate change with 

regard to park facilities. For example, they are preparing for problems associated with storm surge through innovative efforts, such as 

elevating existing facilities, constructing mobile buildings that can be 

relocated inland during hurricanes, and replacing fixed docks 

with floating or removable platforms. Through prudent 

planning, the National Park Service is protecting the 

American taxpayer’s investment. 

P r o t e c t i n g N a t u r a l A r e a s

The Research Natural Area in Dry Tortugas National Park is one example of the National Park 

Service commitment to protect south Florida’s 

ecosystems. The 46-square mile no-take marine protected area will reduce human impacts 

to coral reefs in the park. Many scientists believe 

that a healthier marine ecosystem will be more resilient to the effects of climate change. Managers plan to use 

the area to monitor the impacts of climate change on coral reefs 

over time.

C l i m a t e F r i e n d l y P a r k s

While some impacts to national parks are likely unavoidable, park managers across the country are 

doing what they can to minimize the effects of climate change. In some cases, they may be forced to reconsider standard approaches to resource management. For instance, if sea level rise threatens to cause the extinction 

of species, managers must then decide if they should allow “nature” to take its course, or if they should attempt to relocate 

these plants and animals. Although scientists can anticipate such dilemmas, they aren’t able to predict all of the challenges climate 

change will bring. 

National Park Service personnel are taking the issue seriously by preparing for a future with climate change. As participants in the 

“Climate Friendly Parks” program – a voluntary effort to respond to climate change – south Florida’s national parks are doing their 

best to minimize their contribution to this problem by reducing the production of greenhouse gases in parks. The National Park 

Service mission to preserve park resources “unimpaired for future generations” rings true now with greater-than-ever urgency. 

W h a t a r e t h e N a t i o n a l P a r k s D o i n g ?

photo: Joy Brunk, ENP

South Florida Natural Resources Center • 950 N Krome Avenue • Homestead, FL 33030 • (305) 224 - 4200