In less than two months, the National Oceanic and Atmospheric Administration (NOAA) will release its outlook for the number of hurricanes that will make landfall in the United States in 2022. This lets people predict whether the season will be above or below average hurricane activity. Communities along Florida’s central Gulf Coast may soon benefit from a similar red tide system, a tool that could help people better plan their vacations and help communities mitigate or reduce economic damage.

Red tides in Florida waters are seasonal algal blooms caused by marine dinoflagellates called dinoflagellates short kalenia They likely originated offshore before winds and currents pushed them to shore. Fish kills, sickness or death of manatees, and respiratory irritation for beachgoers and residents are the most common effects during red tide events. Financial losses from lost tourism funds can also be substantial. A recent study found that during the protracted 2018 red tide, Airbnb lost as much as $70 million, with an economic knock-on effect of up to $317 million, almost five times as high.

Another important study sheds light on the severity of red tides along Florida’s Gulf Coast between 1950 and 2019, and most importantly, why some blooms cause more breathing distress than others. NOAA researcher Rick Stumpf and colleagues constructed an annual index of red tide bloom severity based on 70 years of data. K. brevis cell count level.They also generated a respiratory irritation index, which measures exposure to K. short.

The researchers found that from the early 1990s to 2019, the severity of algal blooms increased substantially. One reason: Scientists have increased sampling rates, and therefore more testing. But it’s also possible that nutrients or higher sea temperatures are causing more severe blooms. Second, their results showed that, historically, September was the month when people experienced the highest levels of respiratory distress. Third, and most convincing, they found unusually low levels of respiratory irritation during some moderate flowering months. One possible reason: Offshore winds push the venomous snake venom people breathe out to sea.

dead fish on the beachdead fish on the beach
© Emily Crowell

More research is needed to confirm their findings, but this study suggests that scientists may be on the cusp of making more precise predictions of red tide-driven respiratory irritation. Beach condition forecasts can be made with a higher degree of certainty if wind directions can be reliably forecasted weekly or even monthly during flowering. In addition, researchers may one day be able to assess how specific drivers, such as nutrient loading in the Gulf of Mexico, salinity levels or Saharan dust deposition, contribute to the severity of blooms in nearshore waters. (Saharan dust storms contain iron that indirectly promotes the growth of red tide organisms). If we can link nutrient loads to red tide severity, we will have a clearer cause-and-effect relationship and a stronger incentive to control them.

A more robust system for forecasting seasonal red tide stimulus levels based on NOAA’s annual hurricane outlook would be a relevant and useful tool that the public and businesses can use to plan vacations or book events and associated changes in personnel needs. Like hurricanes, red tides are actually an annual phenomenon along Florida’s Gulf Coast that residents, tourists and businesses can’t completely avoid. However, monthly and even seasonal red tide outlooks derived from new science will help people better prepare and make informed decisions.

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