NOAA and agency partners continue to monitor a bloom of Karenia brevis, the Florida red tide organism that has been persisting in some coastal areas in Southwest Florida. Blooms are patchy in nature and the impacts vary by location and throughout the day depending on nearby bloom concentrations, ocean currents, surf conditions, and wind speed and direction.
NOAA issues Red Tide forecasts for Florida to help local residents and visitors continue to enjoy activities in areas that are temporarily affected by a bloom by making informed decisions about their recreational choices. The forecasts also aid public health managers who coordinate response efforts and mitigate the effects of red tide.
Harmful algal blooms occur nearly every summer along the nation's coasts. Often, the blooms turn the water a deep red. While many people call all such events "red tides," scientists prefer the term harmful algal bloom.
A red tide, or harmful algal bloom, is the rapid growth of microscopic algae. Some produce toxins that have harmful effects on people, fish, marine mammals, and birds. In Florida and Texas, this is primarily caused by the harmful algae species, Karenia brevis. It can result in varying levels of eye and respiratory irritation for people, which may be more severe for those with pre-existing respiratory conditions (such as asthma). The blooms can also cause large fish kills and discolored water along the coast.
NOAA uses a combination of satellite imagery and water samples of the algae species Karenia brevis collected from the field by local partners, to forecast the location and intensity of red tide events. Satellite imagery is a key tool for detecting blooms before they reach the coast, verifying bloom movement, and forecasting potential respiratory irritation.
The conditions reports for red tide in Florida and Texas are available to the public and give the daily level of respiratory irritation forecasts by coastal region. NOAA also issues HAB bulletins that contain an analysis of ocean color satellite imagery, field observations, models, public health reports, and buoy data. The bulletins also contain forecasts of potential Karenia brevis bloom transport, intensification and associated respiratory irritation based on the analysis of information from partners and data providers. These bulletins are primarily issued to public health managers, natural resource managers, and scientists interested in HABs. A week after the HAB bulletin is issued; it's posted to the Bulletin Archive where the public can access it. Resource managers and decision makers can request a bulletin subscription online.
Did you know?
Less than one percent of algal blooms actually produce toxins. Not all algal blooms are harmful, some can actually be beneficial. Phytoplankton are found at the base of the marine food chain, therefore all other life in the ocean relies on phytoplankton. Blooms can also be a good indicator of environmental change not only in the water, but also on land.