South Florida encompasses a three-county area of the southeastern part of the United States. It is also known as Miami Fort Lauderdale Pompano Beach metropolitan Area which covers three counties namely, Miami Dade, Palm Beach and Broward. Global warming will present South Florida serious challenges that will threaten human health, economic prosperity and treasured natural resources. The changes in sea level, climate and average temperature will affect the beaches, water resources, agriculture and ecosystem of Florida. Around 95% of Florida’s 16 million population work within 35 miles of coastal area and around 67 counties in Florida border the Gulf of Mexico or the Atlantic Ocean. The Everglades, coral reefs, the keys and other areas define the Florida’s coastline and generates over $15 billion of revenue being a major tourist attraction.
Global warming is a phenomenon which occurs whenever there is an increase in the average temperature of Earth’s surface. Many experts estimate that the average temperature will rise additionally 2.5 to 10.4 degree F (1.4 to 5.8 degree C) by 2100 (Mastrandrea). The most important cause of worry is that natural ecosystems might not be able to acclimatize to the rapid climate changes and the ecosystem might get heavily disturbed. A basic ecosystem comprises of the living beings and physical environment in any geographic region. Global warming may cause much more harm than expected. Through this paper, I wanted to highlight the affects of Global warming on the ecosystem or the environment in South Florida with a special focus on the endangerment of Coral Reefs. This paper assesses Florida’s specific vulnerabilities regarding ecosystem. Global warming will drastically change the state of Florida.
Scientists predict that Projected Global warming will raise Florida’s average temperature by between 4 and 10 degrees Fahrenheit over the next 100 years. The summer heat index increase of 8 to 15 degrees Fahrenheit will be the most dramatic in the nation. Sea levels could rise by 8 inches to over 2 feet by the year 2100. Rainfall is anticipated to become more intense but also more sporadic, causing worse droughts and storms. (NRDC, 2001)
Global warming causes sea levels to rise as melting glaciers add water to the ocean and warmer water expands due to heating. This drastic heating will cause horizontal advancement of sea rather than vertical rise. As a result, which could cause floods within the neighboring coastline.
A 2006 study found that with only a 15 inch sea level rise, nearly 50 percent of saltmarsh and 84 percent of tidal fl ats in key coastal areas would be inundated and lost, further threatening populations of many commercially and recreationally valuable fi sh species in Florida including: bonefi sh, fl ounder, gag, grouper, grey snapper, permit, popano, red fi sh, snook, spotted sea trout, tarpon (NRDC, Global Warming’s Effects on Florida’s Oceans and Coasts Demand Immediate Action)
1. Coral Reef in South Florida
Florida is the only state in United States that has extensive shallow coral reef formation around its coast. These coral reef extend from Stuart on the Atlantic coast to Dry Tortugas in the Gulf of Mexico. It runs parallel to the emergent keys for 356 km. There are various coral reef types like stony corals, black corals, gold corals, gorgonians, pennatulaceans, true soft corals, stylasterids with majority of them existing near the shore while others found over 10-12 km offshore. An approx of 7000 coral reefs are found in between Key Biscayne and Dry Tortugas. Florida’s coral reefs came into existence 7000 years ago when the sea level rose following the Wisconsin Ice Age. Corals were discovered on the Blake Plateau in the 1880s and investigated in the late 1950s and early 1960s (Squires 1959; Stetson et al. 1962)
Coral reefs are basis for Florida’s sports activities and commercial fisheries. These coral reefs will likely become victims of the global warming. They can survive or grow only a narrow range of temperature (23 to 29 degree Centigrade), salinity (32 to 42 parts per thousand) and water clarity. The light levels generally must be consistent throughout the year for optimal growth. Some coral reefs can tolerate higher temperature but only for a limed time frame after which they die. Over the next few decades, these coral reeds and associated marine organisms will not survive under the changing conditions. Reef growth is generally very slow. It grows between one to sixteen feet in every 1000 years.
Stony corals are the major reef architects. Polyps, the living portion of the coral extract calcium from sea water and combine it with carbon dioxide to construct the elaborate limestone skeletons that for the reef backbone.
Coral Reef fall under the category of animals. A complex microscopic plants known as zooxanthellae live within the animal tissues of reef corals. Coral Reefs are benefitted from the energy provided by the plants during photosynthesis. In turn, the plants are protected by the coral tissues and gain nutrients from the reef corals wastes. Zooxanthellae are the reason behind the color seen in coral reefs.
Coral reef development occurs only in specific environment characteristics such as a solid structure for the base, warm and predictable water temperatures, oceanic salinities, clear, transparent water low in phosphate and nitrogen nutrients and moderate wave action to disperse wastes and bring oxygen and plankton to the reef.
A survey at Looe Key, one of the more diverse reefs in the Florida Keys, reported 63 taxa of stony corals, 42 species of octocorals, and two species of fire coral. Stony corals and octocorals dominate offshore patch reef habitat. Massive corals include: Montastrea faveolata, Montastrea cavernosa, Solenastrea bournoni, Dendrogyra cylindrus, and giant brain coral. Millepora complanata, Acropora palmata, boulder corals, head corals, and soft corals are typical on the bank reef. Boulder corals are most prominent on the intermediate reef where colonies of Porites are sometimes over 1 m in diameter. Platelike growth forms of Agaricia agaricites, Montastrea faveolata, Montastrea cavernosa, and Madracis mirabilis, and deepwater octocorals such as Ellisella barbadensis and Iciligorgia schrammi are common on the deep and outlier reefs. (Duffy 2007)
Current Situation of Corel Reef
- Current estimates note that 10 percent of all coral reefs are degraded beyond recovery. Thirty percent are in critical condition and may die within 10 to 20 years. Experts predict that if current pressures are allowed to continue unabated, 60 percent of the world's coral reefs may die completely by 2050 (CRTF)
- Approximately half of the coral reef ecosystem re-sources under U.S. or FAS jurisdiction are considered by scientists to be in ‘poor’ or ‘fair’ condition and have declined over time due to several natural and anthro-pogenic threats. (CRCP)
- Reef habitats adjacent to populated areas tend to ex-perience more intense threat levels related to issues like coastal development and recreational use, but even remote reefs far from human settlements are im-periled by illegal fishing, marine debris, and climate-related impacts such as bleaching, disease and acidi-fication. (CRCP)
Effect of Global Warming on Coral Reefs
Coral reefs are threatened by three key impacts which are pollution, unsustainable fishing and global climate change. Climate change or global warming has been identified as the greatest global treats to coral reefs. As temperatures rise, mass bleaching and infectious disease outbreaks are likely to become more frequent. Additionally, carbon dioxide (CO2) absorbed into the ocean from the atmosphere has already begun to reduce calcification rates in reef-building and reef-associated organisms by altering sea water chemistry through decreases in pH (ocean acidification). In the long term, failure to address carbon emissions and the resultant impacts of rising temperatures and ocean acidification could make many other management efforts futile. (NOAA)
The NOAA National Ocean Service coral reef “Threats” article states, “Climate change impacts have been identified as one of the greatest global threats to coral reef ecosystems.” As oceans become warmer, due to global warming, coral reef bleaching and “infectious disease outbreaks” are likely to increase, according to the article. Other treats are Coral Reef Disease, Hurricanes and tropical storms, ocean tourism and water recreation, damage to ocean vessels discharging pollutants and debris (Nelson, 2009).
One diver who scoped the 50-foot-deep waters off Palm Beach before the state could examine the damage called it the worst he's ever seen from a single incident. Added Ed Tichenor, director of Palm Beach County Reef Rescue, who reported the damage to state agencies: "As far as I've been diving here, I haven't heard of a similar incident of this magnitude." The other damaged reef is located off a state park just south of Port Everglades. There, sponges have been sliced, and soft and hard corals cut and turned over. (Florin, 2008)
"The future is horrific," says Charlie Veron, an Australian marine biologist who is widely regarded as the world's foremost expert on coral reefs. "There is no hope of reefs surviving to even mid-century in any form that we now recognize. If, and when, they go, they will take with them about one-third of the world's marine biodiversity. Then there is a domino effect, as reefs fail so will other ecosystems. This is the path of a mass extinction event, when most life, especially tropical marine life, goes extinct." (Adam)
Alex Rogers, a coral expert with the Zoological Society of London, talks of an "absolute guarantee of their annihilation". And David Obura, another coral heavyweight and head of CORDIO East Africa, a research group in Kenya, is equally pessimistic: "I don't think reefs have much of a chance. And what's happening to reefs is a parable of what is going to happen to everything else." (Adam)
Occurrence of low tide tidal exposes the coral heads and can damage shallow water reefs (reef flat and reef crest). Chronic emersions during daytime damage the coral system more when heat and sunlight are strong. Due to exposure to ultraviolet radiation, corals get overheated and release zooxanthellae which lead to a phenomenon called “Coral Bleaching”. Even due to continuous exposure to cold and rainy climate, corals can get damaged.
Natural phenomena, such as the El Nino weather pattern, can have lasting, and sometimes devastating, effects on coral reefs. During an El Nino season, easterly trade winds weaken which depresses normal oceanic upwelling processes and affects the climate. Rainfall increases along the eastern Pacific, while Indonesia and Australia experience drought conditions. El Niño can lead to increased sea-surface temperatures, decreased sea level, and altered salinity due to excessive rainfall (Forrester, 1997). During the 1997-1998 El Nino season, extensive and severe coral reef bleaching occurred, especially in the Indo-Pacific region, and the Caribbean. Approximately 70 to 80 percent of all shallow-water corals were killed on many Indo-Pacific reefs (NMFS, 2001). During the same year, coral reefs in the Florida Keys experienced bleaching events ranging from mild to severe (NMS, 2001).
Evidences indicate that the storms and hurricanes are becoming more intense due to the rise in ocean temperature and coral reef dying. Research suggests that in one year time period, sixteen percent of the world’s coral reefs were wiped out. A sea temperature change of a mere one degree Celsius would yield similar losses.
Global warming has yet again endangered aquatic life and species.It has far serious affects than assumed. Coral reefs are now in danger due to the change in the climate. They have numerous advantages or benefits which are as follow:
Coral reefs are colorful aquatic forests which teem with life and acts as a natural barrier for the coastal regions of United States. Coral reefs are habitats for numerous other plants and animals and provide food and shelter to them. Some commercially valuable species like hagfishes, chain dogfish, cutthroat eels, conger eel, shortbeard codling, reef codling, western roughy, red bream, blackbelly rosefish, atlantic thornyhead and wreckfish flock around the deep-coral habitat. Different type of crabs including galatheoids are found in abundance on the deep reefs. Other intertebrates like ophiuroids are also found in large number on the deep reefs. They provide natural storm protection by forming a breakwater. These coral reefs attract fishermen and in turn generate huge revenue for the state.
The large, powerful waves that accompany hurricanes and cyclones can break apart or flatten large coral heads and scatter fragments (Barnes & Hughes, 1999; Jones & Endean, 1976).