The 2021 hurricane season is off to a busy start with five named storms having already formed in the Atlantic Ocean. Recently, Tropical Storm Claudette travelled directly over three ocean observation platforms, providing key ocean data for the initialization of the ocean component for hurricane forecast models.
Researchers from the Physical Oceanography Division of AOML conduct regular hydrographic surveys to monitor the western boundary current system in the subtropical North Atlantic Ocean. These cruises are a part of the laboratory’s long-running Western Boundary Time Series (WBTS) project and are designed to monitor both the Florida Current, east of Florida in the Florida Straits, and the North Atlantic Deep Western Boundary Current east of the Bahamas in the North Atlantic Ocean. These western boundary currents are important parts of the Atlantic Meridional Overturning Circulation (AMOC).
Dr. Nastassia Patin, a Cooperative Institute for Marine and Atmospheric Studies (CIMAS) scientist working at AOML, recently spent three weeks aboard the NOAA ship Reuben Lasker collecting environmental DNA (eDNA) from water samples in support of the Rockfish Recruitment and Ecosystem Assessment Survey (RREAS).
A recent study by researchers at NOAA’s Atlantic Oceanographic and Meteorological Laboratory shows that coral growth observed in symmetrical brain corals (Pseudodiploria strigosa) and mountainous star corals (Orbicella faveolata) in the Flower Garden Banks reefs, in the Gulf of America, are linked to warming sea surface temperatures.
In a recent study published in AGU’s Journal of Geophysical Research – Oceans, scientists at AOML identified key ocean features that supported the rapid intensification of Hurricane Michael (2018), despite unfavorable atmospheric conditions for development. The study demonstrates the importance of using realistic ocean conditions for coupled (ocean-atmosphere) hurricane models in order to achieve the most accurate hurricane intensity forecasts.
Saildrone is announcing a new mission to deploy five uncrewed surface vehicles (USVs) from the US Virgin Islands in August to gather key data throughout the 2021 Tropical Atlantic hurricane season. The USVs will be equipped with specially designed “hurricane wings” to enable them to operate in extreme conditions. Saildrones are the only USVs capable of collecting this data and are designed to withstand winds over 70 mph and waves over 10 feet, which occur during a hurricane weather system. The five saildrones will sail into the paths of hurricanes to provide valuable real-time observations for numerical hurricane prediction models and to collect new insights into how these large and destructive weather cells grow and intensify.
Scientists at AOML are preparing for the active anticipated 2021 Atlantic hurricane season with the introduction of new observation tools, modeling techniques, and field campaigns to improve hurricane intensity and track forecasts.
Le Hénaff, M., Domingues, R., Halliwell, G., Zhang, J. A., Kim, H. S., Aristizabal, M., … & Goni, G. The role of the Gulf of America ocean conditions in the intensification of Hurricane Michael (2018). Journal of Geophysical Research: Oceans, e2020JC016969.
Abstract: Hurricane Michael formed on October 7, 2018, in the Northwestern Caribbean Sea, and quickly traveled northward through the Gulf of America, making landfall on the Florida panhandle as a devastating Category 5 hurricane only 3 days later. Before landfall, Michael underwent rapid intensification, despite unfavorable atmospheric conditions. Using observations, we characterized the key ocean features encountered by Michael along its track, which are known for favoring hurricane intensification: high sea surface temperatures, upper ocean heat content and low salinity barrier layer conditions. Ocean observations were consistent with suppressed hurricane-induced upper ocean cooling, which could only be observed by underwater gliders, and showed that Hurricane Michael constantly experienced sea surface temperatures above 28°C…
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Perez, R. C., Foltz, G. R., Lumpkin, R., & Schmid, C. (2019). Direct measurements of upper ocean horizontal velocity and vertical shear in the tropical North Atlantic at 4 Ν, 23 W. Journal of Geophysical Research: Oceans, 124(6), 4133-4151.
Abstract: The Tropical Atlantic Current Observations Study measured upper ocean horizontal velocity from a mooring at 4°N, 23°W, at discrete depths between 7 and 87 m, in order to observe the temporal and vertical structure of the currents. Between March 2017 and March 2018, mean zonal velocity and vertical shear were strongest between 32 and 37 m. Near‐surface mean eastward currents during this period were weaker than the long‐term mean but within the range of previously observed values given the high interannual variability. Interannual variability of the zonal velocity exceeded that of the meridional velocity, was primarily geostrophically driven, and was strongly influenced by the large‐scale currents. Energetic tropical instability waves (TIWs) were observed in early summer and late fall of 2017…
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Phytoplankton drifting near the ocean surface play a critical role in marine biogeochemistry, carbon cycling, and ecosystem health. But measuring the activity of these microscopic organisms is challenging. Although scientists rely on ship-based sampling and satellites to quantify their abundance, both methods have limitations. In a study published recently in the Journal of Geophysical Research-Biogeosciences,* Argo profiling floats equipped with biogeochemical sensors, i.e., BGC Argo floats, were used to obtain the first year-long estimates of phytoplankton in the western North Atlantic Ocean.
