Florida's diverse ecosystems include both shellfish and coral reefs- two habitats considered among the most vulnerable to acidification. The Florida Keys is a hotspot of scientific activity in the Southeast, where scientists are collecting information about how both water chemistry and ecosystems are changing. In Tampa Bay, scientists deployed sensors to track acidification and are answering questions about how seagrass beds can mitigate against changing ocean chemistry.
There are three continuous monitoring stations in Florida waters. One at Cheeca Rocks in the Florida Keys, a system recently installed in Tampa Bay, and a buoy approximately 70 nautical miles offshore of Tampa Bay. There are also numerous monitoring efforts, where water samples are collected regularly or ships are equipped with monitoring equipment.
IS CARBON DIOXIDE INCREASING? Like most coastal regions, it takes time to detect a trend because of high natural variability in water chemistry. The longest continuous time series in Florida is at Cheeca Rocks in the Florida Keys. Installed in 2011, scientists estimate this buoy can be used to detect a trend within the next few years. Other systems, in Tampa Bay and on the West Florida Shelf, are too new to detect long term trends but will provide insights into variability across seasons and locations.
CHEMISTRY IN SEAGRASS BEDS: Seagrasses are submerged plants that take up carbon dioxide just like plants do on land. Multiple studies have shown that seagrass beds can locally elevate pH and offer refugia from acidification. However, some scientists note these coastal habitats do experience very high variability, which could limit the habitat's ability to serve as refugia for sensitive organisms.
AT THE FLORIDA KEYS: Carbonate chemistry (e.g. carbon dioxide concentrations, pH, and the amount of carbonate in the water) changes seasonally in South Florida. In the summer, inshore reefs dominated by seagrasses show lower CO2 concentrations as the photosynthesizing plants absorb CO2 from the seawater. In addition, coral reefs directly influence seawater chemistry, where dissolution of carbonate skeleton and sediments can increase concentrations of carbonate in seawater. Calcification of corals can locally decrease concentrations of carbonate in seawater.
CONSIDERING COASTAL ACIDIFICATION: As mentioned in the primer on acidification, carbon dioxide from the atmosphere is not the only cause of acidification. Unlike many other estuarine systems in the Atlantic, freshwater input in Florida estuaries is not always correlated with low buffering capacity (total alkalinity) and low carbon dioxide seawater. Recent studies showed hotspots of coastal acidification in coastal inlets, where nutrient- and carbon-rich water meets the ocean.
CHEECA ROCKS: A MAPCO2 system was deployed at Cheeca Rocks in 2011. Cheeca Rocks is an inshore patch reef within the Florida Keys National Marine Sanctuary.
TAMPA BAY: The Tampa Bay Land/Ocean Biogeochemical Observatory (LOBO) was installed in December 2017. This mooring will provide insights into how chemistry is changing in response to restoration efforts in the bay and the role of seagrasses in mitigating against acidification.
WEST FLORIDA SHELF: Acidification monitoring sensors were installed in early 2019 on an existing buoy 70 miles west of Tampa Bay. This system will help scientists connect the dots between the Tampa Boy monitoring system and the water chemistry dynamics offshore. Learn more about the deployment of this system and access links to the data here.
GOMECC/ECOA: The Gulf of Mexico Ecosystems and Carbon Cycle (GOMECC) and East Coast Ocean Acidification (ECOA) cruises each occur every 3 years with multiple transects off the coast of Florida. The research cruise is supported by the National Oceanic and Atmospheric's Ocean Acidification Program. Learn more about their monitoring efforts here.
AOML SOP: NOAA's Atlantic Oceanographic Marine Laboratory (AOML) Ocean Carbon Cycle group operates a Ship of Opportunity (SOP) CO2 consortium. There are currently 17 ships equipped with automated monitoring equipment. Some of these ships operate primarily in the U.S. Southeast, collecting carbonate chemistry information continuously through their travels.
NCRMP: NOAA's National Coral Reef Monitoring Program (NCRMP) collects water samples for carbonate chemistry measurements in coral reef ecosystems around the world, including sites in the Florida Keys. Learn more about this effort and access the data here.
Florida's reefs extend from St Lucie Inlet to the Dry Tortugas in the Gulf of Mexico and research shows most coral species are vulnerable to acidification. Florida also has a vibrant shellfish industry, particularly in the panhandle where socioeconomic vulnerability to acidification is high. Learn more about what recent research has shown about the impacts of acidification on Florida ecosystems:
DOES THE FLORIDA REEF TRACT PROVIDE OCEAN ACIDIFICATION REFUGIA? As mentioned previously, seagrasses draw down carbon dioxide from seawater for photosynthesis. This process locally increases pH and concentrations of carbonate, creating better conditions for coral growth. In Florida, inshore reefs, that are close to shore and seagrass beds, could offer ocean acidification refugia for coral reefs. But what about when photosynthesis is slower at night and in the fall and winter? Studies have shown net dissolution (more dissolution than calcification) for some Florida reefs in fall and winter.
WILL ACIDIFICATION AFFECT ALL CORALS EQUALLY? Laboratory experiments show some corals are more tolerant than others to increases in temperature and acidification. Though three abundant species of corals showed negative effects, the massive starlet coral was resistant to acidification in the laboratory. This means some reefs could be more tolerant than others to changing conditions.
IS CORAL GROWTH ALL THAT MATTERS? Scientists analyzed skeletal growth over centuries in the Florida Reef Tract. They found that growth (extension and calcification) has not significantly changed, but the density of the skeleton has decreased. This means the skeleton is weaker and could be more vulnerable to bioerosion, where organisms like sponges break down the coral skeleton. Other studies show food availability can offset the negative affects of acidification on coral growth. Scientists suggest placement of protected areas or coral nurseries should consider locations with high natural food availability.
What about the other organisms?
HARMFUL ALGAL BLOOMS: There have not been many studies investigating the affects of acidification on harmful algal blooms (HABs) in Florida, but laboratory studies show an increase in growth of the common harmful algal species Karenia brevis under high carbon dioxide conditions. Studies in other regions show HABs may have a selective advantage over other types of plankton under acidification. Mote Marine Laboratory has recently added carbonate chemistry measurements to their ongoing HAB research, which will help us understand bloom growth in relation to both nutrients and acidification.
SHELLFISH: Shellfish are common in Southeast estuaries and acidification can affect their shells, growth and mortality rates, particularly for larval shellfish. Clam and oyster farms are common in Florida and as a consequence, some areas of the state are particularly economically vulnerable to acidification. A large scale study that looked at trends of pH in Florida estuaries found that pH has decreased in 8 out of 10 estuaries since 1980, though the rate of decrease appears to be slower than open ocean conditions.
Florida's coral reefs and shellfish estuaries are important resources culturally and economically. Furthermore, they serve as vital coastline protection from storms and erosion.
THE CORAL REEF INDUSTRY: Florida's coral reefs support a massive industry that generates $5.7 billion in sales and income. This economic value comes from visitors that support local economies near the reefs, the recreational boating industry, and the recreational fishing industry. What can be done to address coral reef degradation? In addition to curbing carbon dioxide emissions, recent research shows the importance of managing runoff of nutrients and sewage for coral health. Managing runoff is also an important strategy in curbing coastal acidification.
THE SHELLFISH INDUSTRY: Shellfish aquaculture is relatively new in Florida and is dominated by clam farming. The total economic impact was valued at $38.7 million. Florida leads the nation in number of clam farms and fourth for overall mollusk sales. Studies of socioeconomic vulnerability show that the shellfish industry in Florida's panhandle is particularly vulnerable to acidification due to both nutrient runoff and rivers with low buffering capacity. Similar to solutions presented for coral reefs, managing fertilizer, nutrient and sewage runoff will contribute to more resilient shellfish habitats with global change.
COASTLINE PROTECTION: Recent research shows that coral reefs in Florida protect $675 million worth of infrastructure and economic activity annually and as much as $1.8 billion in the case of a severe storm. Previous studies have shown sea floor erosion (e.g. loss of reefs) is occurring in tandem with rising seas, rendering Florida more vulnerable to coastal hazards. Maintaining healthy reefs is essential to protect Florida coastlines against rising seas, erosion and storms.
WHO ARE THE SCIENTISTS?
U.S. Geological Survey
Dr. Kimberly Yates is a senior research scientist at the U.S. Geological Survey, St. Petersburg
Center for Coastal and Marine Science and founding member of the Steering Committee for the Southeast Ocean and Coastal Acidification Network (SOCAN). She specializes in integrated science studies that examine how changes in coastal ecosystem processes may impact or mitigate risks from coastal hazards, using a whole system perspective that considers the interactions and linkages among chemistry, biology and the physical environment. Much of her recent work has focused on how coral reef seafloor erosion changes risks from sea level rise, waves and storms; impacts on coral reefs and estuaries from coastal and ocean acidification; and identifying and characterizing coastal climate change refuges.
NOAA Cooperative Institute for Marine and Atmospheric Studies at the University of Miami
Dr. Leticia Barbero is a chemical oceanographer at NOAA's Cooperative Institute for Marine and Atmospheric Studies at the University of Miami. In her role, she works with NOAA's Atlantic Oceanographic and Meteorological Laboratory to study the carbon dioxide system in the ocean, specifically ocean acidification in the coastal waters of the East Coast and Gulf of Mexico.
Mote Marine Laboratory
Dr. Emily Hall joined the Chemical Ecology Program at Mote Marine Laboratory in 2005, researching and monitoring nutrient patterns in relation to harmful algal blooms in the west-central coast of Florida, and investigating sources of nutrients in aquatic systems. She currently manages Mote's Ocean Acidification Program, where she has developed ocean acidification and climate change experimental systems (in the Florida Keys - OAFTERU and in Sarasota - OASys) to study the effects of global and local variables on coral reef ecosystems as well as on other marine organisms. She is the SOCAN Science Working Group Chair.
James W. Fourqurean
Florida International University
Dr. Jim Fourqurean is a Professor of Biological Sciences and Director of the Center for Coastal Oceans Research at Florida International University in Miami. Dr. Fourqurean researches ecological and biogeochemical processes in coastal plant communities, including carbon and nutrient cycling. He is one of the lead scientists in the International Blue Carbon Working Group and he also serves as a scientific representative to the International Blue Carbon policy Working Group. These groups have highlighted the importance of carbon cycling for climate change mitigation and influenced the decision to include these ecosystems in national greenhouse gas inventories. For 10 years, Dr. Fourqurean has focused on translating the science of carbon dynamics in coastal ecosystems into actionable policy and climate change mitigation strategies.
University of Miami
Dr. Chris Langdon is a Professor of Marine Biology and Ecology at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science. Dr. Langdon is a co-founder of the South Florida Coral Reef and Climate Change Lab, which has been active since 2007 in researching how corals respond to acidification and warming. His research includes laboratory experiments on biomineralization and larval survivorship, as well as field studies to understand effects of natural variability and how corals currently cope with extreme conditions. He has served as an instructor for ocean acidification workshops internationally and actively organizes and participates in acidification stakeholder roundtables in South Florida.
NOAA, Atlantic Oceanographic and Meteorological Laboratory
Ian Enochs is a principal investigator of ACCRETE. His research focuses on understanding the responses of corals and reef biota to global change. He is particularly interested in the impacts of warming and ocean acidification on the persistence of coral reef framework structures that provide essential habitat and support numerous ecosystem services. Enochs applies a multidisciplinary approach, conducting research in both the laboratory and the field, as well as developing new technologies to address pressing research questions. He is a co-PI of the National Coral Reef Monitoring Program, and leads several projects pertaining to the Coral Reef Conservation Program’s restoration pillar and NOAA’s Omics initiative. Enochs is a research ecologist with the Ocean Chemistry and Ecosystems Division of NOAA’s Atlantic Oceanographic and Meteorological Laboratory in Miami.
NOAA, Atlantic Oceanographic and Meteorological Laboratory
Derek Manzello is a principal investigator of ACCRETE, the coral reef climate change and ocean acidification monitoring of NOAA’s National Coral Reef Monitoring Program (NCRMP), which is co-funded by NOAA’s Coral Reef Conservation Program and Ocean Acidification Program. Dr. Manzello manages the climate and acidification sentinel monitoring site at Cheeca Rocks within the Florida Keys National Marine Sanctuary, one of three such sites within the wider Atlantic. He is also a co-PI on the National Science Foundation funded project "Are eastern Pacific Reefs becoming more resilient to ENSO?" that is a collaboration with the University of California-Los Angeles, the University of the Virgin Islands, the Lamont-Doherty Earth Observatory (LDEO) of Columbia University, and the Rosenstiel School of Marine and Atmospheric Science at the University of Miami (RSMAS). He is a research oceanographer with the Ocean Chemistry and Ecosystems Division of NOAA’s Atlantic Oceanographic and Meteorological Laboratory in Miami.