Nicole Castilla
The rapidly rising temperatures around the globe are causing harm to our planet, impacting ecosystems everywhere. One specific region in particular that is being affected is the state of Florida and its freshwater wetlands. Florida’s freshwater ecosystems are some of the most biodiverse and dynamic communities the Sunshine State has to offer. Unfortunately, due to the warming climate, the rapid influx of people moving to Florida, and urbanization, those resources are slowly depleting. Although resilient, the freshwater systems can only take so much. Restoration initiatives are being implemented to rehabilitate the declining ecosystems; however, it is crucial to protect our precious planet before it is too late.
Climate change is wreaking havoc on the beautiful state of Florida and creating dire consequences for the state’s freshwater systems and resources. However, we must look to the future and pursue steps toward a healthier earth. As outlined in the 2030 Agenda for Sustainable Development, the United Nations is taking steps towards a more sustainable future and a cleaner planet for all by the year 2030. This agenda, guided by the three principles of sustainability–society, the environment, and the economy– aims to provide solutions for protecting the earth while advocating for societal well-being and economic prosperity. Collectively, these principles are believed to enable conditions for complete global health by protecting all aspects of the biosphere. Florida’s unique climate vulnerabilities, its projected population growth to over 23 million and counting, and economic reliance on a healthy environment make it an appropriate case study for analysis utilizing the three principles of sustainability.
Sea Level Rise
The rise in sea levels is predominantly caused anthropogenically, with humans being the driving force behind the release of carbon dioxide into the atmosphere. When carbon dioxide is released into the atmosphere, it becomes trapped in the atmosphere, hence its notoriety as a greenhouse gas. The trapped carbon dioxide absorbs and radiates heat back to Earth, which in turn, causes temperatures to rise. The burning of fossil fuels, which has become the leading cause of climate change, is a major contributor to sea level rise. Other anthropogenic factors such as deep sea mining and deforestation largely contribute to the release of carbon dioxide into the atmosphere. When temperatures in the ocean increase, glaciers and polar ice caps melt, causing water to run off into the ocean and increase sea levels.
You may have heard the term “sea level rise” in correlation to the ocean, but did you know the rising seas also impact freshwater wetlands? When seawater rises, naturally occurring salts are brought inland and mixed into coastal waters and unfortunately sometimes, fresh bodies of water. Once it reaches freshwater, the saltwater contaminates it and causes problems for both the wildlife in the wetland and humans alike.
Saltwater Intrusion
This intrusion of salinity ends up inundating the freshwater ecosystems, leading to many problems for freshwater wetlands. Saltwater intrusion can cause heavy metals and chemicals to seep into the soil, thus contaminating the groundwater. Some aquatic species do not tolerate saltwater and die off as a result. When a species’ population declines or disappears completely, it can lead to disturbances in that particular environment such as altered food chains and decreased biodiversity. Grasses that grow in freshwater environments can also become affected by saltwater intrusion. When saltwater mixes with freshwater in soil, it can harm the grasses and potentially kill them.
Most of Florida’s drinking water supply comes from the Floridan Aquifer, the largest freshwater aquifer in the southeastern United States. However, if salt accumulates there, it can damage the water which in turn, will negatively impact the people who depend on this source for their drinking water. When seawater makes its way into a freshwater aquifer, the presence of salt in the water can lead to health complications if a person drinks it. Drinking water with a high concentration of salt can contribute to hypertension, kidney damage, and even dementia for those who consume it, especially in people with preexisting health conditions. With this said, saltwater intrusion can cause serious damage to both the environment and the people of Florida.
Hurricanes
Climate change is also affecting the way hurricanes impact the world. In the past few years, there has been an increase in storms, especially intense hurricanes, reaching categories 4 and 5 and leaving catastrophic damage in the aftermath. Last year, hurricanes Helene and Milton ravaged through the southeastern United States, creating a path of devastation in its wake. The warmer the temperatures in the ocean are, the easier it becomes for hurricanes to form since they need warm water and air to form and pick up strength.
Hurricanes are a major cause of storm surge, which occurs when strong hurricane-force winds push seawater inland, causing flooding and serious destruction, especially in coastal communities. However, some storm surges can be so strong that they can reach lakes, rivers, and other bodies of freshwater throughout Florida and cause much harm. Saltwater entering a freshwater wetland can lead to fish kills, algal growth, and disruption of the freshwater environment, leading to its degradation.
Hurricanes not only cause calamities and casualties but also economic hardships. When a hurricane damages critical infrastructure such as buildings or roads, they have to be either completely rebuilt or repaired, causing financial burdens on individuals and the government as well. Supply chains also become disrupted, leading to further financial strain.
Warm Water Temperatures
Water temperatures that are higher than normal can significantly affect the water quality of freshwater bodies of water and also disrupt aquatic organisms. When temperatures in the water become elevated, they can stress aquatic life and alter the nutrients in the water. For example, American alligators exhibit a phenomenon known as temperature-dependent sex determination, where their sex is determined by the temperature in which their eggs are incubated. Cooler temperatures around 30℃ produce mostly females and warmer temperatures around 33℃ produce males. Increased temperatures affect the sex of the alligators, leading to a greater population of males and an imbalance in sex ratios. If this trend continues, there could eventually be a disproportionate number of male-to-female alligators and possible threats of extinction if the males are left with no females to breed with.
Warm water temperatures can also cause cyanobacteria, commonly known as blue-green algae, to grow in freshwater environments. When an excess of cyanobacteria accumulates in freshwater, harmful algal blooms can occur which can lead to a variety of problems for both the environment and public health. Cyanobacteria can “soak up the sun” as they take in sunlight through the process of photosynthesis and release heat back into the water.
The climate may be rising; however, you have the power to make waves of change. Reduce your water use and limit the amount of water you use daily. Consider Florida and its freshwater wetlands every time you step in the shower or water the lawn. Spread the word with others and share your newfound knowledge about how Florida’s freshwater ecosystems are being affected by climate change. There is no planet B and once the natural resources are destroyed beyond the point of restoration, they are gone–forever. The choices you make today will have a lasting impact on the future.
Stay tuned for Part 2 of the Florida’s Freshwater Ecosystems series, where Lexi Davidson discusses all about how the climate crisis is impacting public health in Florida!
Citations
United Nations. (n.d.). Transforming our world: The 2030 agenda for sustainable development | department of economic and social affairs. United Nations. https://sdgs.un.org/2030agenda#:~:text=They%20are%20integrated%20and%20indivisible%20and%20balance,sustainable%20development:%20the%20economic%2C%20social%20and%20environmental.&text=We%20are%20determined%20to%20protect%20the%20planet,needs%20of%20the%20present%20and%20future%20generations.
NASA. (2024, October 23). Causes - NASA science. NASA. https://science.nasa.gov/climate-change/causes/#:~:text=Human%20Activity%20Is%20the%20Cause,air%20to%20make%20CO2.
NASA. (2023, August 15). Carbon dioxide concentration. NASA. https://climate.nasa.gov/vital-signs/carbon-dioxide/?intent=121
U.S. Energy Information Administration - EIA - independent statistics and analysis. Greenhouse gases - U.S. Energy Information Administration (EIA). (n.d.). https://www.eia.gov/energyexplained/energy-and-the-environment/greenhouse-gases.php#:~:text=Several%20major%20greenhouse%20gases%20that%20result%20from,(PFCs)%20Sulfur%20hexafluoride%20(SF6)%20Nitrogen%20trifluoride%20(NF3)
Lindsey, R. (2024, April 9). Climate change: Atmospheric carbon dioxide. NOAA Climate.gov. https://www.climate.gov/news-features/understanding-climate/climate-change-atmospheric-carbon-dioxide#:~:text=Carbon%20dioxide%20is%20Earth%27s%20most,including%20back%20toward%20Earth%27s%20surface.
United Nations. (n.d.-a). Causes and effects of climate change. United Nations. https://www.un.org/en/climatechange/science/causes-effects-climate-change
Leyden, E., Farkas, J., Hutson, J., & Mosley, L. M. (2022). Short-term seawater inundation induces metal mobilisation in freshwater and acid sulfate soil environments. Chemosphere, 299, 134383. https://doi.org/10.1016/j.chemosphere.2022.134383
Florida’s aquifers. St. Johns River Water Management District. (2025, February 25). https://www.sjrwmd.com/water-supply/aquifer/#:~:text=The%20largest%20aquifer%20in%20the,America%20and%20the%20Atlantic%20Ocean.
Metych, M. (2024, September 23). saltwater intrusion. Encyclopedia Britannica. https://www.britannica.com/science/saltwater-intrusion
How does the ocean affect hurricanes?. How does the ocean affect hurricanes? : Ocean Exploration Facts: NOAA Office of Ocean Exploration and Research. (n.d.). https://oceanexplorer.noaa.gov/facts/hurricanes.html
Storm surge. Storm Surge | U.S. Climate Resilience Toolkit. (n.d.). https://toolkit.climate.gov/storm-surge
Pullaro, A. (2024). The Economic Impact of Hurricanes and Natural Disasters. Michigan Journal of Economics. https://sites.lsa.umich.edu/mje/2024/11/25/the-economic-impact-of-hurricanes-and-natural-disasters/#:~:text=The%20true%20economic%20toll%20of%20a%20hurricane,supply%20chains%2C%20labor%20markets%2C%20and%20government%20spending.&text=Direct%20impacts%20are%20focused%20on%20the%20immediate,long%2Dterm%20disruptions%20to%20trade%2C%20employment%2C%20and%20productivity.
National Institutes of Natural Sciences. (2015, December 23). How temperature determines sex in alligators. ScienceDaily. Retrieved March 1, 2025 from www.sciencedaily.com/releases/2015/12/151223134112.htm
Yirka, B. (2021). (publication). Climate change could alter the gender ratios of American alligator offspring. Science X Network. Retrieved February 27, 2025, from https://phys.org/news/2021-05-climate-gender-ratios-american-alligator.html#:~:text=They%20found%20that%20the%20gender,More%20information:%20Samantha%20L.
Environmental Protection Agency. (2025, February 26). Climate Change and Freshwater Harmful Algal Blooms. EPA. https://www.epa.gov/habs/climate-change-and-freshwater-harmful-algal-blooms#:~:text=Scientists%20continue%20to%20document%20many,other%20algae%20at%20warmer%20temperatures