South Florida, located in the United States, is impacted by ocean acidification more than any other state in the country. Florida has 1,350 miles of coastline, which residents and organisms rely on significantly (Manzello, 2015). There are serious impacts associated with Florida's ocean acidification problem that are becoming known. Major changes in Florida's shellfish growth and corals calcification, reproduction, and growth decreases are emerging problems. Changes to shellfish and coral populations are going to have serious negative economical impacts on Florida's residents and businesses. South Florida is home to a substantial number of sport fish, a contributor to that industry. Florida depends greatly on tourism and recreational and commercial fishing for revenue. Coral reef tourism in Florida supports more than 70,000 jobs and generates $2.8 billion (Manzello, 2015). Saltwater fishing adds a further 109,000 jobs to Florida's communities (Okazaki, 2017). The increasing acidity of seawater is resulting in coral bleaching and a decrease in prime fisheries (IPCC, 2014). Ocean acidification, therefore, threatens Florida's environment, economy, and lifestyle.
The major global hazard impacting South Florida is ocean acidification. As the ocean absorbs carbon dioxide it alters the ocean chemistry of seawater and interactions with marine species. The regional hazards for South Florida consist of mass coral bleaching, change in migration patterns, abundance, and loss of calcium carbonate ions (IPCC, 2014).
Ocean Acidification Process
Ocean acidification affect how and what we eat, earn a living, and provide for our communities. The ocean absorbs about a quarter of the carbon dioxide we release into the atmosphere every year (Jokiel, 2016). This uptake changes the ocean's chemistry, a process called ocean acidification (IPCC, 2014). Oceans are typically slightly alkaline, around 8.0-8.2 on the pH scale (Okazaki, 2017). Ocean acidification reduces pH levels.
Exposure and Vulnerability
Ocean warming and acidification impact the formation and maintenance of coral reefs and the goods and services that they provide. South Florida communities are highly dependent on reef ecosystems for lifestyle, livelihoods, food security, coastal protection, and reef-based tourism (Hoegh-Guldberg, 2012). South Florida's communities are highly susceptible to the hazards of coral bleaching and risk impacts on human health and lifestyles. There is a potential increase in internal migration and urbanization (IPCC, 2014).
Nearly 275 million people globally reside within 18 miles of coral reefs (Kavousi, 2016). Coral reefs contribute to protecting the shoreline from the destructive forces of storm surges and cyclones (Sheppard et al., 2005), including the small islands of the Florida Keys. This protective role is threatened by the decrease in coral cover, reduced rates of calcification, and higher rates of dissolution and bio-erosion due to ocean warming and acidification (IPCC, 2014).
If coral reefs disappear in South Florida the long-term viability of these crucial marine ecosystems will affect the millions of species that rely on the habitats developed by coral. When fish are displaced from their habitats there are sensitivities that shift the performance and distribution of fish (Manzello, 2015). The warming ocean causes shifts in the abundance, geographic distribution, migration patterns, and timing of seasonal activities of marine species (IPCC, 2014). The redistribution of fish to higher latitudes poses significant risk to South Florida's income, supplies, and businesses. The redistribution of fish will decrease fisheries catch potential and species richness in South Florida (Doney, 2016). This change will severely affect South Florida's tourism and recreational and commercial fisheries, which will have negative economical impacts. As fishing opportunities change as fish abundance falls it leaves risks of disease and invasive species (Doney, 2016). Disease and invasive species will have serious impacts on the South Florida fisheries and ecosystems. It will cause high local extinction rates and further pushes fish populations to higher latitudes (IPCC, 2014).
Ocean Acidification Models
Models provide an overview of the chemical, biological and socioeconomic impacts of ocean acidification and policy options.
This mode is an multi-model simulated time series of global mean ocean surface pH from 1850-2100. It shows the effects of near-future acidification (seawater pH reduction of < 0.5 units) on significant variables.
A more acidic ocean has intensified impacts on various calcifying species. Calcifying species consists of oysters, clams, sea urchins, corals and some plankton. When calcifying organisms are at risk it has the potential to put the entire marine food web in jeopardy (Jokiel, 2016). Currently, nearly a billion people globally depend on marine organisms as their main source of protein (Scherner, 2016). This puts fisheries and coastal livelihoods at risk (IPCC, 2014). The global cost of production loss of mulluscs could be more than US$100 billion by 2100 (IPCC, 2014).
Adaptation and Resilience
Reducing stressors that exacerbate ocean acidification conditions is a key adaptation and will benefit South Florida. To support resilience of coral reefs South Florida communities can reduce coastal pollution, increase water quality, and reduce overfishing of important species (Scherner, 2016). The scope of reducing stressors focuses on growth, calcification, and reproduction rather than on repairing damage (IPCC, 2014). By reducing land-based pollution in coastal waters in South Florida it will limit nutrient runoff of phosphorus, nitrogen and land-based carbon inputs that increase ocean acidity (Jokeil, 2016). A key strategy to address this issue is reinforcing existing environmental laws. The U.S Clean Water Act is an important environmental law that can help battle ocean acidification by limiting runoff and associated pollutants to control increase ocean acidity and coastal erosion (Manzello, 2016). Marine protected areas and fisheries management have the potential to increase ecosystem resilience and increase the recovery of coral reefs after climate change impacts (IPCC, 2014). Other forms of resource management such as catch limits and gear restrictions can also help fight ocean acidification in South Florida.
With the IPCC (2014) stating high confidence for the loss of coral reefs and ecosystem service, loss of livelihood, coastal settlements and economic stability in the near future, the responsibility of South Florida's response is necessary. Mitigation of ocean acidification through reduction of atmospheric carbon dioxide is the most effective and the least risky method to limit ocean acidification and it impacts. Geoengineering techniques to remove carbon dioxide from the atmosphere could directly address the problem but are very costly and may be limited by the lack of carbon dioxide storage capacity (IPCC, 2014).
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