As tropical storm Edouard was forming in the Eastern Atlantic west of the Cape Verde Islands, a team of hurricane scientists from NOAA’s Hurricane Research Division (HRD) and the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science were taking to the skies to deploy a series of highly specialized instruments to collect critical information on ocean and atmospheric conditions along the storm’s predicted track.
For the last four years, UM Rosenstiel School Professor Nick Shay, a SECOORA Prinicipal Investigator, and researchers Benjamin Jaimes and Jodi Brewster have been working closely with engineers at Lockheed Martin in Marion, Massachusetts, the manufacturer of the expendable ocean probes, to prepare the instruments to collect the valuable data necessary to help forecast where and when a newly developed tropical storm would intensify into a category hurricane.
On Friday, Sept. 12 when Edouard was a mere day-old tropical storm, the research team, including Jaimes from the UM Rosenstiel School Upper Ocean Dynamics Laboratory and UM alumni and NOAA hurricane scientist Eric Uhlhorn, departed St. Croix in the U.S. Virgin Islands aboard NOAA’s P3 hurricane hunter aircraft. On this first flight they deployed a total of 27 of the specialized ocean sensors to survey the ocean conditions ahead of the predicted storm track.
Three types of specialized ocean probes were deployed into the ocean to measure currents, temperature and salinity. All of these factors provided Edouard the fuel necessary to intensify. Eight were dropped from the aircraft to measure currents to a depth of 1500 meters (4921 feet), seven to survey water temperature and salinity at a 1000 meters (3280 feet) depth, and twelve others to measure ocean temperatures at up to 400 meters (1312 feet) depth.
Using daily satellite-based heat maps produced by Shay’s research group at the UM Rosenstiel School in conjunction with the field data, the team was able to identify where the ocean temperatures where high enough to fuel the storm’s steady intensification into a hurricane.
Jaimes and third-year Ph.D. graduate student Johna Rudzin, were aboard NOAA’s aircraft for in-storm flights on Sept. 14, 15 and 16 to measure ocean thermal structure and ocean currents in the eye of the storm. During these in-storm flights, lead by NOAA's Ocean Winds Science Team and HRD, the UM team deployed 23 additional sensors to evaluate the in-storm ocean temperature response that will be used to help improve intensity forecast models. During a fifth and final flight on Sept. 17, they deployed more probes, a total of 38, over the same region as the Sept 12 pre-storm flight to collect information on the ocean conditions after Edouard passed through on its way into the Central Atlantic as a category-3 hurricane.
“The research missions were a tremendous success with nearly 90% of the probes returning great data,” said Shay. “This was in large part due to an extensive collaborative effort between our UM team and the engineers at Lockheed Martin.” NOAA provided invaluable aircraft time during the test flights.
Rudzin was able to add one more in-flight experiment before the team headed back to St. Croix to study the warm, deep water eddies spinning off the North Brazil Current, located offshore of northeastern Brazil, into the Caribbean Sea. Similar to the eddies of the Gulf of Mexico’s Loop Current that helped intensify Hurricane Katrina, these warm-core features originating from the North Brazil Current could be important pieces of information to forecast hurricane intensification in the North Atlantic. Rudzin deployed a total of 54 probes into a deep, large eddy to collect critical data on these important hurricane-fueling stations.
The UM team returned from the week-long hurricane field experiment with valuable data necessary for scientists to improve hurricane forecast models, now and in the future.