The biennial COAWST Modeling System Training was held in James B. Hunt Library at NC State University from February 25-28, 2019. Over 100 researchers attended in person or on line to learn more about the Couped Ocean-Atmosphere-Wave-Sediment Transport Model System. Developers and expert users of WRF (Weather Research and Forecasting model, the atmospheric component), SWAN (Simulating WAves Near shore, the wave component), and ROMS (the Regional Ocean Model, the ocean component), gave tutorials and demonstrations on each model separately and how they interact. Users from around the world traded case studies, tips, techniques, new features, and additional tools for COAWST.
Dr. John Warner of the U.S. Geological Survey and Dr. Ruoying He of NC State University’s Department of Marine, Earth, and Atmospheric Sciences hosted the workshop. Dr. Warner developed the COAWST modeling system and moderates and maintains it. Dr. He’s Ocean Observing and Modeling Group were involved in developing COAWST and includes expert users. They thank everyone who attended the event and made it a success.
Applications of the COAWST Modeling System include characterizing and predicting shore erosion, African easterly winds that generate the hurricanes which hit North America, Southern Ocean ice thickness and extent, wave effects on currents, sediment transport in estuaries, tropical cyclone paths and intensity, rip currents, and many more oceanographic and meteorological interactions.
Contact Dr. John Warner (jcwarner [at] usgs [dot] gov) for more information on the COAWST Modeling System.
COAWST Reference: Warner, J., B. Armstrong, R. He, and J. Zambon (2010) Development of a Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system, Ocean Modelling, 35(3), 230-244, doi: 10.1016/j.ocemod.2010.07.010
Dr. Ruoying He and the Ocean Observing and Modeling Group has been awarded a major grant as part of the National Academies of Sciences, Engineering, and Medicine investigation of the Gulf of Mexico’s Loop Current. OOMG’s numerical modeling project is the largest of eight new projects that will advance our understanding of the Loop Current using a multifaceted approach that includes modeling, adding more oberving infrastrucutre, and data compilation.
The research project will use numerical modeling and data observations to deepen our understanding of the Loop Current, the dominant circulation feature in the Gulf. Entering through the Yucatan Channel and exiting through the Florida Straits, this fast, warm, saline flow is the precursor to the Gulf Stream. The Loop Current sheds eddies at irregular intervals; these strong circular flows translate westward across the Gulf, impacting activities, structures, biology, and water conditions.
NC State University is the lead institution for this cooperative effort. Dr. He will be joined by Scripps Institute of Oceanography, Massachusetts Institute of Technology, Florida State University, UC Santa Cruz, and the Center for Scientific Research and Higher Education at Ensenada (Mexico) in using data assimilative modeling and high-performance computing to understand Loop Current dynamics and evaluate ocean observation systems in the Gulf.
Four NCSU College of Sciences faculty members were honored as Goodnight Innovative Distinguished faculty in a ceremony on 26 November 2018. Dr. Jim Goodnight, co-founder and CEO of SAS, and his wife Ann are long-time supporters of NC State, generously donating to the university. Dr. Goodnight is an NCSU alumnus.
Goodnight Innovative faculty honored a the ceremony were Drs. Phil Castellano, Harald Ade, Roy He, and Fred Wright. NCSU Chancellor Randy Woodson presented the award plaques, and College of Sciences Dean Chris McGahan spoke.
As a token of appreciation, Dr. He presented the Goodnights with a print of the submersible Alvin, operated by Woods Hole Oceanographic Institution. Dr. He has himself dove in Alvin, to 2800 m deep in the Gulf of Mexico.
Dr. Roy He, head of OOMG, and Dr. John Warner of the U.S. Geological Survey will co-host a workshop on the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) numerical model in February 2019. The workshop will be four days of intensive instruction in the capabilities, applications, and operations of the COAWST coupled modeling system. Instructors include the developers of the modeling components as well as expert users.
The workshop’s audience is COAWST users who have a basic knowledge of this modeling system and want to develop their own application, discuss issues, share approaches, learn new features, and interact with a broad user community.
For details, registration, and contact info, see the COAWST Workshop website. Questions can be sent to Jennifer Warrillow at jawarril [at] ncsu [dot] edu
The bottom-mounted research instruments utilized by Processes Driving Exchange at Cape Hatteras (PEACH) scientists sit anywhere from 20 meters to more than 3000 meters beneath the surface of the ocean. These instruments measure the entire water column above using a variety of remote and in situ methods of data collection. With exception to 2 moorings utilizing surface-based meteorological instruments, there is no evidence at the surface that the instruments are there. During the April 2017 deployment mission, the moorings were dropped into the deep ocean and the coordinates of the deployment were logged. A signal was then sent from the ship to confirm that the instruments arrived safely on the seafloor.
Now, 18 months later, we return to collect these instruments off of the ocean bottom, retrieve the data from their internal data loggers, and bring them back to shore for refurbishment. Radio communication is useless to oceanographers attempting to communicate with seafloor-based instruments. Instead we have to rely on acoustic communication. Upon arrival at one of these subsurface mooring stations, scientists will tap into the ship’s acoustic transducers and send a high frequency (12KHz) signal to the ocean bottom. Hopefully, the acoustic transducers below will be able to pick up this signal and wake up the rest of the mooring’s acoustic transceivers for further instruction.
After some communication to ensure that the instrument has been working as planned, a release signal is sent to the mooring sitting on the seafloor. An electric current is then passed through a wire until it burns away, a pin is released, and the instrument is freed from the mooring and floats to the surface. The instrument’s rise to the surface is apparent as the time between pings received by the ship becomes less and less (denoted by the upside-down Y in the attached image. Once on the surface, the floating instrument has a flashing strobe that can be seen for miles around by shipboard personnel. If the floating instrument cannot be found visually, it also has a radio beacon that the ship can hone in to retrieve. The instrument is then captured and brought on deck.
The R/V Neil Armstrong was tasked with deploying Argo floats into the Gulf Stream. Argo floats are designed to sink to around 1000m and drift along with the currents at that depth. After about 2 weeks of drifting at 1000m, they float back to the surface over approximately 6 hours, collecting temperature and salinity data as they rise through the water column. Once at the surface, they transmit data to shore via satellite and repeat their sink/drift/float/transmit mission again. At any given time, there are approximately 4,000 Argo floats in the global oceans. The data they provide is extremely useful for scientific research and model improvement and validation.
As the Processes Driving Exchange at Cape Hatteras (PEACH) scientific expedition is taking place in and around the Gulf Stream, one of the strongest western boundary currents in the world, three Argo floats were given to the ship for deployment in the PEACH study region. Once the Armstrong arrived in the Gulf Stream, all 3 floats were deployed within 6 hours across the Gulf Stream.
For the researchers onboard, the deployment of these floats was designed to be fairly simple and unobtrusive to their research efforts. Once at a station of interest, these floats are taken to the back (fantail) of the ship. Rope is secured to the straps of the Argo float and the float is lowered gently into the water. Then, a water-activated latch is released allowing the cardboard box containing the Argo float to float away from the straps. The rope and straps are brought back onto the ship while the cardboard box containing the Argo float drifts away and eventually breaks apart. The Argo float then starts the first of its many sink/drift/float/transmit missions until it is recovered at regular service and end-of-life intervals.
OOMG members Dr. Joe Zambon (Research Assistant Professor), Shun Mao (Ph.D. Student) and the rest of the multi-institutional Processes Driving Exchange at Cape Hatteras (PEACH) team arrived in their study region and science operations began. While the R/V Neil Armstrong has been recording important scientific data since leaving the dock in Woods Hole, MA, the first in situ measurements of the study region took place this afternoon. A line of 12 eXpendible BathyThermographs (XBTs) were deployed from the continental shelf to deep offshore along a line. Approximately every 10 kilometers, an XBT was dropped from the deck of the ship into the water. Each XBT measures water temperature from the ocean surface to 760m below. An individual deployment shows one station’s temperature versus depth profile, when you string several of them together, you are able to produce a transect.
The transect will show important characteristics of the surface and sub-surface composition of the Gulf Stream in the PEACH study region. This allows the PEACH science team to make observations as to the evolution of the Gulf Stream throughout this observation period. These observations, along with observations that have been recorded during the previous 2 cruises, and observations taken by the in situ instrumentation that has been sitting in the ocean for over 18 months, will provide a unique and powerful dataset that can be used to answer hypotheses regarding Gulf Stream characteristics and provide ground-truth for modeling studies to validate against.
As this was the first deployment of XBTs on this cruise, a CTD (Conductivity, Temperature, and Depth) rosette was also deployed at the final station to provide a cross-reference to ensure that the observations and fall profiles of the XBTs are valid. (The cross-validation plot is attached.)
OOMG members Dr. Joe Zambon (Research Assistant Professor), Shun Mao (Ph.D. Student) and the rest of the multi-institutional Processes Driving Exchange at Cape Hatteras (PEACH) team departed from the Woods Hole Oceanographic Institute dock at Woods Hole, MA early Saturday morning. Their trip to the continental shelf break off of North Carolina is expected to take approximately 40 hours as the R/V Neil Armstrong will stay close to the shoreline to avoid excessive waves when possible.
Planning for science operations continued immediately after leaving the dock. Dr. Harvey Seim (UNC Professor), the expedition’s Chief Scientist, held a meeting of all onboard scientists and the Armstrong’s science liaison officers (also known as the SSSGs, Shipboard Scientific Services Group). During that meeting, individual goals were discussed while highlighting any overlapping opportunities between different scientific objectives.
The forecast is expected to be favorable for the scientists and crew of the Armstrong for at least a few days into the middle of next week. The priority during favorable weather is to recover buoys and bottom-mounted moorings that were left for data collection in the initial PEACH cruise during April 2017. Recovering these instruments will allow the PEACH team to begin analysis of an extensive dataset spanning back 18 months. After recovery of these instruments, as time and weather allows, the ship will be directed to stations of interest to collect shipboard data, deploy the CTD (Conductivity, Temperature, and Depth) instrument rosette, collect subsurface water samples, launch rawindsondes (weather balloons), and deploy eXpendible BathyThermographs (XBTs).
OOMG members Dr. Joe Zambon (Research Assistant Professor) and Shun Mao (Ph.D. Student) arrived at the Woods Hole Oceanographic Institute (WHOI) to board the R/V Neil Armstrong early Thursday morning. They are taking part in the final cruise of the NSF-funded Processes Driving Exchange at Cape Hatteras (PEACH). Upon their arrival, they checked in with the Chief Scientist for this expedition (AR-33), UNC Professor Dr. Harvey Seim. Most of their equipment for deploying eXpendible BathyThermographs (XBTs) and rawindsondes (a.k.a. weather balloons) were shipped directly to the vessel. They will spend the next day verifying operation of instruments on the Armstrong, along with securing an antennae and cables to one of the higher decks for communication with the rawindsondes.
Their departure was originally scheduled for early Friday morning; however, the CNAPS model is predicting a strong storm to pass through the northeastern U.S. with gale force winds and 5+ meter waves (CNAPS prediction attached). This forecast, consistent with other forecast models, has postponed the departure of the Armstrong until after the storm has passed. NSF-sponsored vessels build in a few “weather” days so the delay is not expected to impact their work. As long as the waves calm down quickly after the storm’s passage on Friday (as forecast in CNAPS), they should be able to leave Saturday morning for the continental shelf break off of North Carolina.
NOAA Deputy Administrator Dr. Neil Jacobs, an NCSU alumnus, conducted a listening session in November 2018 at NCSU to discuss NOAA’s efforts to improve weather research to operations, develop a community-based weather model, and advance seasonal to subseasonal weather forecasts. Dr. Jacobs also took questions and gathered input from the public.
[Photo, L to R: Dr. Joe Zambon (OOMG), Dr. Neil Jacobs (NOAA), Dr. Jay Levine (Dept. Marine, Earth, and Atmospheric Sciences), and Dr. Roy He (OOMG)]
OOMG lab manager Jennifer Warrillow spoke to engineering students at Sanderson High School in Raleigh, NC in November 2018 about the application of engineering principles to oceanography. Specifically, she explained the design and mechanics of OOMG’s Autonomous Underwater Vehicle (AUV), a Slocum G1 glider. Principles discussed include:
- how to make the vehicle watertight
- how to balance components inside the glider and component design features that allow the user to adjust them
- how a vehicle with no propulsion can move in a programmed direction using buoyancy, pitch control, and a rudder
- why the glider, a tube of metal, doesn’t sink straight to the bottom
- how the glider communicates with its shore-based pilot while at sea
- what an altimeter does for an underwater vehicle
- how the glider uses its burn weight to surface when all else fails
Students had the opportunity to handle parts of a Slocum glider, although the glider itself was awaiting deployment at the University of North Carolina’s Coastal Studies Institute.
OOMG was pleased to host Dr. Conrad Lautenbacher’s visited NC State University in October 2018. Dr. Lautenbacher is a retired Navy Vice Admiral, former Undersecretary of Commerce for Oceans and Atmosphere, eighth administrator of NOAA, and president of the Consortium for Oceanographic Research and Education.
Dr. Lautenbacher presented a Special Dept. of Marine, Earth, and Atmospheric Sciences seminar titled “Science and the Real World” during his visit.
We look forward to interacting with Dr. Lautenbacher in the future!
Members of OOMG attended the Middle Atlantic Bight Physical Oceanography and Meteorology (MABPOM) conference at Woods Hole Oceanographic Institution in October 2018. This annual meeting discusses science of the U. S. east coast from the Gulf of Maine to the continental shelf south of Cape Hatteras, NC.
OOMG members contributed to the conference this year with four presentations:
- Impact of Hurricane Florence on the coastal circulation dynamics: preliminary analyses, by Ruoying He
- Investigation of shelf-ocean exchange pathways near Cape Hatteras, NC based on realistic ocean model simulations, by Shun Mao
- From top to bottom an investigation of wintertime atmosphere-ocean interaction in the vicinity of the Gulf Stream in January 2018, by Joseph B. Zambon
- Investigation of marine physical-biogeochemical interactions during storm conditions, by Laura McGee
The Kenan Institute of Engineering, Technology, and Science (KIETS) at NC State University has generously continued their funding support of OOMG’s research on Dynamical Model Downscaling of Climate Change and Its Impacts on Marine Environmental Conditions Off North Carolina for a second year. This support leverages other funding on physical oceanographic processes around Cape Hatteras, NC and will enable OOMG to increase the resolution of fine-scale modeling of ocean currents, including the Gulf Stream. Together, KIETS and OOMG will provide important information to benefit coastal stakeholders and communities.
We thank KIETS for their continued support and appreciate this productive relationship.
OOMG Ph.D. student Laura McGee has won the first Vembu Subramanian Ocean Scholars award from the Southeast Coastal Ocean Observing Regional Association (SECOORA). Laura will use the financial award to present her research as scientific meetings, network with other scientists, and disseminate her research results. She develops and uses cutting-edge data analysis techniques to investigate the role of hurricanes in air-sea CO2 flux.
Vebmu Subramanian was the Deputy Director of RCOOS and DMAC operations for SECOORA. Although his time was tragically cut short, his friends and colleagues honor his memory and legacy by continuing his support for students and the next generation of ocean experts. Details of the Vembu Subramanian Ocean Scholars award can be found here.