Physical Oceanography Data Sets

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  • Software
    Stable barotropic coastal trapped wave modes: edge, shelf and Kelvin waves
    (Woods Hole Oceanographic Institution, 2020-08-01) Brink, Kenneth H.
    This set of Matlab mfiles (all with names beginning with “bwavesp”) can be used to calculate barotropic coastal wave properties in the absence of density stratification. The wave frequency is taken to be entirely real (hence stable). You are allowed to have a mean alongshore flow, if desired, and you can apply the rigid lid and/or coastal long wave approximations. The model can be run in the non-rotating limit if desired. Once a wave’s frequency is found, the modal structure is displayed, and a perturbation (weak friction) imaginary correction to the wave frequency is found. The code can use an exact open boundary condition or a closed condition at either side of the domain.
  • Dataset
    Slab boundary layer model simulations for “Dynamical importance of the trade wind inversion in suppressing the southeast Pacific ITCZ”
    (Woods Hole Oceanographic Institution, 2023-10-05) Gonzalez, Alex O.
    Sea surface temperature (SST) gradients are a primary driver of low-level wind convergence in the east Pacific Inter-Tropical Convergence Zone (ITCZ) through their hydrostatic relationship to the surface pressure gradient force (PGF). However, the surface PGF may not always align with SST gradients due to variations in boundary layer temperature gradients with height, i.e., the boundary layer contribution to the surface PGF. In this study, we investigate the observed northern hemisphere position of the east Pacific ITCZ using a slab boundary layer model (SBLM) driven by different approximations of the boundary layer virtual temperature field. SBLM simulations using the entire boundary layer virtual temperature profile produce a realistic northern hemisphere ITCZ. However, SST-only simulations produce excessive equatorial divergence and southern hemisphere convergence, resulting in a latitudinally-confined double ITCZ-like structure. Observed virtual temperature gradients highlight the importance of northward temperature gradients strengthening with height from the equator to 15 degrees south below the trade wind inversion (TWI). Our interpretation is that the equatorial cold tongue induces relatively weak high surface pressure and double ITCZ-like convergence because the resulting layer of cold air is shallow. Concurrently, relatively strong high surface pressure spreads out in the southern hemisphere due to interactions between stratocumulus clouds and the ocean surface. Together, the equatorial cold tongue and the TWI/stratocumulus clouds enable a more northern hemisphere dominant ITCZ. Thus, we provide evidence of a dynamical link between the equatorial cold tongue, low clouds, and double ITCZs, which continue to be problematic in Earth system models.
  • Dataset
    Long-term, quality-controlled observations of near-shore wind momentum and heat flux at the Martha’s Vineyard Coastal Observatory’s Air-Sea Interaction Tower
    (Woods Hole Oceanographic Institution, 2024-01-05) Chang, Yun ; Kirincich, Anthony R.
    Quality-controlled atmospheric and oceanic observations of the wind momentum flux and heat flux in the surface layer above the ocean are provided based on data collected at Martha’s Vineyard Coastal Observatory (MVCO). The main dataset consists of wind speed, momentum flux, and heat flux observations made in 16 years over a 20 year period at measurement heights of 20 m above mean sea level. Ancillary data for comparison with bulk formula such as coare 3.5 (Edson et al. (2013)) include air temperature, relative humidity, air pressure, ocean surface temperature, ocean current speed, and solar radia- tion. MVCO is composed of three main elements, an Air-Sea Interaction Tower (ASIT, 3 km south of Martha’s Vineyard in 17-m water; Figure 1a), a Meteorological Mast (Met, 4 km northeast of ASIT), and an 12-m underwater node (UN, 1.6 km northeast of ASIT in 12-m water). The majority of the observations were collected at ASIT, while the ancillary data are from a combination of ASIT, Met, and UN.
  • Dataset
    Near-full-depth profile observations of water properties and currents at four deep-ocean sites
    (Woods Hole Oceanographic Institution, 2023-07-17) Toole, John M. ; Musgrave, Ruth C. ; Fine, Elizabeth C. ; Steinberg, Jacob M. ; Krishfield, Richard A.
    The Ocean Observatory Initiative (OOI) funded by the U.S. National Science Foundation established four deep ocean observing sites between summer 2013 and spring 2015: Argentine Basin (42˚ 58.9’ S, 42˚ 29.9’ W, water depth 5200 m), Southern Ocean (54 ˚ 28.1’ S, 89˚ 22.1’ W, 4800 m), Station Papa (50˚ 4.2’ N, 144˚ 47.9 W, 4219 m), and Irminger Sea (59˚ 58.5’ N, 39 ˚ 28.9’ W, 2800 m). Each site was instrumented with four closely-spaced moorings of various design supporting a variety of sensors. As no single OOI mooring in these arrays provides temperature, salinity and horizontal velocity information over the full water column, observations from two or more moorings were combined to produce vertical profiles at ½-dbar vertical resolution of sea water temperature, salinity, east and north velocity and vertical displacement. These profile data are reported here.
  • Dataset
    Gridded hydrography and bulk air-sea interactions observed by the Ocean Observatory Initiative (OOI) Coastal Pioneer New England Shelf Mooring Array (2015-2022)
    (Woods Hole Oceanographic Institution, 2023-06-18) Taenzer, Lukas Lobert ; Gawarkiewicz, Glen G. ; Plueddemann, Albert J.
    The Ocean Observatory Initiative (OOI) Coastal Pioneer Mooring Array recorded hydrographic, meteorological, and bulk air-sea flux variables at a variety of moorings across the Southern New England shelfbreak front between late 2014 and November 2022. Here, we provide low-level quality-controlled one- to two-dimensional time series datasets from all OOI Coastal Pioneer Moorings on a uniform spatio-temporal grid, covering the timeframe 2015-01-01 to 2022-06-01. Hydrography data (temperature T, salinity S, pressure P, and potential density (p=0)) is either provided as i) one-dimensional time series or ii) two-dimensional pressure-time data series: i) The static surface buoys, near-surface instrument frames (NSIF), and multi-function bottom nodes (MFBN) of all three surface moorings cover the surface and bottom boundary layer, respectively, and lead to one-dimensional time series at roughly constant pressure levels. ii) The mid-range water column is covered by the Array’s profiler moorings leading to interpolated two-dimensional data varying across pressure and time. Meteorological variables (wind at 3m height, sea level pressure, sea surface humidity, shortwave and longwave radiation, and precipitation) are measured by the three surface buoys. Remaining air-sea buoyancy fluxes are inferred from bulk formulae using COARE3.5 (Edson et al., 2013). The input data is published on the OOI Data Explorer ERDDAP server (erddap.dataexplorer.oceanobservatories.org) and publicly available for download upon registration. The Ocean Observatory Initiative (OOI) is a major facility fully funded by the National Science Foundation (NSF) under Cooperative Agreement No. 1743430 and comes with its own conditions for data usage (https://oceanobservatories.org/wp-content/uploads/2022/12/1102-00020_Data_User_Terms_Conditions_OOI_2019-01-02_Ver_2-00.pdf; May 13, 2022).
  • Dataset
    Overturning in the Subpolar North Atlantic Program (OSNAP) moored current meter, temperature, conductivity, salinity, and pressure data collected on subsurface moorings M1, M2, M3, and M4 between June 2018 and August 2020
    (Woods Hole Oceanographic Institution, 2023-06-07) Bower, Amy S. ; Straneo, Fiamma ; Furey, Heather H. ; Biló, Tiago C. ; Bahr, Frank B.
    As part of the Overturning in the Subpolar North Atlantic Program (OSNAP), four mooring arrays were deployed in the Greenland Deep Western Boundary Current (GDWBC) located off the east coast of Greenland, in the Irminger Sea. The array consisted of four subsurface moorings M1, M2, M3, and M4, containing 30 MicroCATs and 18 Aquadopp Current Meters, and deployed between June 2018 and August 2020. The data sets are timeseries of temperature, conductivity, pressure, and salinity recorded at 15-minute intervals and current meter data collected at 30-minute intervals. The depths of the moorings were 2086 meters, 2436 meters, 2557 meters, and 2984 meters respectively. The data have been fully processed, calibrated, and quality controlled.
  • Dataset
    Data to accompany “Direct observation of wave-coherent pressure work in the atmospheric boundary layer”
    (Woods Hole Oceanographic Institution, 2022-12-29) Zippel, Seth F. ; Edson, James B. ; Scully, Malcolm E. ; Keefe, Oaklin R.
    As described in the methods section of “Direct Observation of Wave-coherent Pressure Work in the Atmospheric Boundary Layer”: Measurements were made from an open-lattice steel tower deployed in roughly 13 m water depth in Buzzards Bay, MA. Buzzards Bay is a 48 km by 12 km basin open on the SW side to Rhode Island Sound. The average depth is 11 m, with a tide range of 1 to 1.5 m, depending on the neap/spring cycles. Winds in Buzzards Bay are frequently aligned on the long-axis (from the NE or SW), and are commonly strong, particularly in the fall and winter. The tower was deployed near the center of the bay at 41.577638 N, 70.745555 W for a spring deployment lasting from April 12, 2022 to June 13th, 2022. Atmospheric measurements included three primary instrument booms that housed paired sonic anemometers (RM Young 81000RE) and high-resolution pressure sensors (Paros Scientific). The pressure sensor intakes were terminated with static pressure heads, which reduce the dynamic pressure contribution to the measured (static) pressure. The tower booms were aligned at 280 degrees such that the NE and SW winds would be unobstructed by the tower's main body. A fourth sonic anemometer (Gill R3) was extended above the tower such that it was open to all wind directions and clear of wake by the tower structure. A single point lidar (Riegl LD90-3i) was mounted to the highest boom, such that the lidar measured the water surface elevation underneath the anemometer and pressure sensors to within a few centimeters horizontally. All instruments were time synchronized with a custom "miniNode" flux logger, that aggregated the data streams from each instrument. Additional atmospheric and wave measurements on the tower included short-wave and long-wave radiometers (Kipp & Zonen), two RH/T sensors (Vaisala), and a standard lower-resolution barometer (Setra).
  • Dataset
    Revisiting HF ground wave propagation losses over the ocean: a comparison of long-term observations and models
    (Woods Hole Oceanographic Institution, 2022-11-29) Kirincich, Anthony R. ; Cinquino, Eve
    This data was collected by Kirincich as part of the NSF-sponsored High Frequency Radar Winds program, with the goal of understanding the errors in present day HFR-based wind extraction algorithms that are due to variations in the signal losses along the transmission path. Understanding variations in the received power levels for land-based high frequency radar systems is critical to advancing radar-based estimates of winds and waves. We use a long-term record of one-way high frequency radar power observations to explore the key factors controlling propagation losses over the ocean. Observed propagation loss was quantified using an 8-month record of radio frequency (RF) power from a shore-based transmitter, received at two locations: an offshore tower and a nearby island. Observations were compared to environmental factors as well as models of path loss incorporating smooth and rough surface impedances and varying atmospheric properties. Significant differences in the observations at the two sites existed. One-way path loss variations at the tower, a wavelength above mean sea level, were closely related to atmospheric forcing, while variations at the distant island site were dominated by wind-driven surface gravity wave variability. Seasonal variability in ocean conductivity had no significant effect on over-ocean path losses. Simplistic analytical models of path loss were found to have more skill than either ground wave propagation models or more complex numerical models of field strength in matching the observations, due in part to under-observation of the atmosphere but also the differences in rough surface impedance between models of ocean waves.
  • Dataset
    2017 HF Radar observations off the East Taiwan Coast
    (Woods Hole Oceanographic Institution, 2021-10-04) Kirincich, Anthony R. ; Hsiao, Yu-hung ; Yang, Y.-J.
    High-frequency radar-based observations of surface currents along the east coast of Taiwan, obtained over a 50-day period in early 2017, are used to examine the occurrence, generation, and downstream advection of submesoscale eddies in the Kuroshio. Measured at an effective depth of 2 m and radial resolution of 3 km from four land-based HF radar systems spanning an 250-km along-stream distance, the surface current observations reveal the instantaneous position of the Kuroshio on hourly time scales as well as the occurrence of numerous high relative vorticity features. Vortex features with spatial scales of 5-20 km were concentrated in the first 30 km offshore, with many created at the southern tip of Taiwan on tidal timescales. Most features, with relative vorticities approaching zeta/f=1, translated northward along the coast at the speed of the Kuroshio itself and were coherent over the 250-km length of the Taiwanese coastline. Both tides and regional winds appear to influence when long-lived features form, and the offshore advection of surface waters by the vortices are observable in intermittent Satellite images of surface chlorophyll. While most features are advected northward with the current, a submarine ridge acts to impede the flow, scattering northward moving features and causing occasional southward-migrating vortices. Data Description: DESCRIPTION; The surface current observations used here were obtained from four long-range (4 MHz transmit frequency) land-based coastal radar systems, operated by the Taiwan Ocean Research Institute (TORI) and the National Taiwan University (NTU). All systems were Codar Ocean Sensors SeaSondes, with the three southern stations operated by TORI, and the northern-most station by NTU. Collected over the time period spanning February 1st to March 26th, 2017, the hourly observations of Doppler cross-spectra had a radial resolution of 3 km. Horizontal resolution was dependent on both the resolution of the measured antenna patterns (1 degree in azimuth) as well as the inherent azimuthal resolution of the radar returns themselves. DATA_PREPARATION_DESCRIPTION; Observed Doppler cross-spectra were reprocessed following Kirincich et al. (2012) using adjusted measured antenna patterns and advanced quality control metrics to estimate the radial surface currents observed at each site. Measured antenna response patterns were adjusted iteratively to reduce radar-to-radar inconsistencies defined using synthetic radials estimated from adjacent radars as well as systematic biases in mean vorticity and divergence patterns. Vector combinations of the radial surface currents, representative of the average currents over the top 2 m of the water column (StewartJoy, 1974) were estimated using power-weighed least-squares methods (Kirincich et al. 2012, Kaplan et al 2005) with a fixed horizontal averaging length-scale of 3 km, and masked for errors due to the geometric dilution of precision (GDOP) greater than 2 (Barrack, 2002). Acquisition Description: SENSOR_INFORMATION; Radio frequency interference from the ionosphere is a particular problem for the TORI and NTU radars, due to a combination of latitude and transmit frequency, causing elevated background noise during local nighttime. Returns at ranges of 90 km, the distance to the primary scattering layer within the ionosphere, are especially affected. SNR was used as an effective screening tool to isolate and eliminate data contaminated by ionospheric radio noise common in the region, adding further improvements to the radial velocity results. However, data from a 50x50 km region directly offshore of the radar site near 23deg 30' N 121deg 30' E was excised during the hours of 11 to 17 UTC each day during the observational period due to poor data returns during times of high ionospheric reflections and radio noise that resulted in poorly resolved and inaccurate vector current estimates. Using synthetic radials from adjacent HFR sites (Emery et al 2019), surface current uncertainties are estimated to be 5-10 cm/s. the west of the 2018-2019 mooring locations. The surface mooring was located at 41.0706degN 70.8177degW in 40 m of water and sampled surface vector winds, air temperature, air pressure, and relative humidity using a Vaisala WXT520 located at 2 m above mean sea level at 10 min ensemble averages, of 1 Hz data. The 2020 surface mooring also had 5 temperature-conductivity sensors (SBE37s) that sampled the oceanic water column at fixed depths below the surface of 0.6,4,6.5,10, and 20-m at 2 min increments. Finally the 2020 subsurface mooring was deployed at 41.0706degN 70.8177degW and contained a sub-surface float at 8-m below sea level in 40 m of water. The float held an upward looking Nortek Signature 1000 AD2CP that collected 2048 pings @4Hz every 20 min at 0.25 m bin depths.
  • Dataset
    Horizontal Stirring over the Northeast U.S. Continental Shelf: the Spatial and Temporal Evolution of Surface Eddy Kinetic Energy
    (Woods Hole Oceanographic Institution, 2021-09-30) Kirincich, Anthony R. ; Flament, Pierre J. ; Futch, Victoria ; Hodges, Benjamin A.
    This data was collected by Kirincich as part of the Submesoscale Dynamics Over The Shelf Study, with field observations in 2018 and 2019, as well as the HFR_winds project with field work in 2020. The analysis products presented were used to examine the space and time scales of eddy kinetic energy over the wide, shallow, NES continental shelf using a novel implementation of HFR to achieve spatial and temporal resolutions sufficient to capture the horizontal scales of velocity variability. The data consists of estimates of the near-surface horizontal (East and North) ocean currents made via High Frequency (HF) radar-based remote sensing of the Ocean backscatter spectrum as well as in situ moored hydrographic, velocity, and surface winds, and mobile surface hydrographic observations collected via autonomous vehicles. Data were collected within three separate measurement periods: July to December 2018, July to December 2019, and October to December 2020.
  • Dataset
    Overturning in the Subpolar North Atlantic Program (OSNAP) RAFOS Float Data collected between June 2014 to January 2019
    ( 2019-08) Furey, Heather H. ; Ramsey, Andree L.
    As part of the Overturning in the Subpolar North Atlantic Program (OSNAP), 137 acoustically tracked RAFOS floats, using 13 moored sound sources, were deployed at five deployment locations (four around the Reykjanes Ridge and one east of Greenland), between 2014 and 2019. The floats were deployed within 200m of the sea floor (1800-2800m) and with density greater than 27.8. They recorded position, temperature, and pressure once a day.
  • Dataset
    Data from the 2018 dye release cruise south of Martha’s Vineyard, MA
    (Woods Hole Oceanographic Institution, 2021-06-24) Rypina, Irina I. ; Kirincich, Anthony R. ; Peacock, Thomas
    On Aug 16-17, 2018 a rhodamine dye experiment was conducted in the coastal ocean south of Martha’s Vineyard, MA. One of the experiment’s aims was to investigate the exchanges, or the absence of such, between the mixed layer and the ocean underneath over a time scale of about a day.
  • Dataset
    Stratification, Wind, and Waves on the Inner shelf of Martha’s Vineyard (SWWIM)
    (Woods Hole Oceanographic Institution, 2021-06-08) Lentz, Steven J.
    Time series of current velocity, water temperature, and salinity profiles, and near-bottom water depth from the 7-m, 12-m, 17-m, and 27-m site of an inner-shelf array deployed as part of the Stratification, Wind, and Waves on the Inner shelf of Martha’s Vineyard (SWWIM) study. There were 6 deployments of an array of four sites across the inner-shelf south of Martha's Vineyard, Massachusetts. The four sites are designated by nominal depth 7-m, 12-m (MVCO node), 17-m and 27-m. Each site consisted of an upwarded looking ADCP mounted on a bottom frame and a surface mooring spanning the water column with temperature and temperature/conductivity instruments. Gaps between deployments varied from 1 to 2 months. Each site was off the south coast of Martha's Vineyard, Massachusetts and the time series span for all four sites was 11 October 2006 – 5 February 2010. Sites: 7-m site was at 41.347°N 70.556°W, 0.4 km offshore in 7 - 8 m of water 12-m site was at 41.337°N 70.556°W, 1.5 km offshore in 12 m of water 17-m site was at 41.319°N 70.570W, 3.8 km offshore in 17.5 m of water 27-m site was at 41.254°N 70.592°W, 11.1 km offshore in 27.5 m of water
  • Software
    Barotropic coastal trapped wave modes with complex frequency: edge, shelf and Kelvin waves
    (Woods Hole Oceanographic Institution, 2020-08-01) Brink, Kenneth H.
    This set of Matlab mfiles (all with names beginning with “bwavesc”) can be used to calculate barotropic coastal wave properties in the absence of density stratification. The wave frequency is complex so that unstable or strongly damped modes can be treated. You are allowed to have a mean alongshore flow, if desired, and you can apply the rigid lid approximation. The model can be run in the non-rotating limit if desired. Once a wave’s frequency is found, the modal structure is displayed. The code can use an exact open boundary condition or a closed condition at either side of the domain.
  • Dataset
    Increased typhoon activity in the Pacific deep tropics driven by Little Ice Age circulation changes
    (Woods Hole Oceanographic Institution, 2020-09-02) Bramante, James F. ; Ford, Murray R. ; Kench, Paul S. ; Ashton, Andrew D. ; Toomey, Michael R. ; Sullivan, Richard M. ; Karnauskas, Kristopher B. ; Ummenhofer, Caroline C. ; Donnelly, Jeffrey P.
    The instrumental record reveals that tropical cyclone activity is sensitive to oceanic and atmospheric variability on inter-annual and decadal scales. However, our understanding of climate’s influence on tropical cyclone behavior is restricted by the short historical record and sparse prehistorical reconstructions, particularly in the western North Pacific where coastal communities suffer loss of life and livelihood from typhoons annually. Here we reconstruct three millennia of deep tropical North Pacific cyclogenesis and compare with other records to explore past regional typhoon dynamics. These records demonstrate low baseline activity prior to 1350 C.E. followed by a rapid culmination in activity during the Little Ice Age. This pattern is concurrent with hydroclimate proxy variability, suggesting a centennial-scale link between Pacific hydroclimate and tropical cyclone climatology. Using an ensemble of global climate models, we demonstrate that migration of the Pacific Walker circulation and variability in two Pacific climate modes during the Little Ice Age contributed to enhanced tropical cyclone activity in the tropical western North Pacific. Changes to Walker Circulation and expansion of the tropics projected for the next century invert Little Ice Age hydroclimate trends, potentially reducing typhoon activity in the deep tropical Pacific.
  • Dataset
    How variable is mixing efficiency in the abyss?
    (Woods Hole Oceanographic Institution, 2020-03-02) Ijichi, Takashi ; St. Laurent, Louis C. ; Polzin, Kurt L. ; Toole, John M.
    This directory contains BBTRE/DoMORE processed data (“all_BBTRE.mat” and “all_DoMORE.mat”) that was used to produce all figures in the above research letter. Each mat file has two structure arrays named “location” and “patch10”. The “location” array includes microstructure profile information used in this study (Table D1). The “patch10” array includes 10-m patch-wise parameter estimates used in this study (Table D2). Note that bulk averaged parameters can be constructed from parameters saved in “patch10” (see the above paper).
  • Dataset
    CTD data from the WHOI-MIT Joint Program Orientation Cruises aboard the SSV Corwith Cramer (2003-2013)
    (Woods Hole Oceanographic Institution, 2020-01-14) Gawarkiewicz, Glen G. ; Harden, Benjamin E.
    CTD data from 11 WHOI-MIT Joint Program Orientation Cruises aboard the SSV Corwith Cramer. Cruises occupied standard sections to the south of Cape Cod across the New England Shelfbreak in late June between 2003 and 2013.
  • Dataset
    Pathways to the Denmark Strait Overflow: A Lagrangian Study in the Iceland Sea
    (Woods Hole Oceanographic Institution, 2019-09) de Jong, Marieke Femke ; Bower, Amy S. ; Søiland, Henrik ; Furey, Heather H. ; Ramsey, Andree L.
    The goal of this project was to directly measure the dense water pathways upstream of the Denmark Strait in the Iceland Sea and compare the results to existing ideas about the dynamics of the circulation by deploying 45 acoustically tracked RAFOS floats over a two year time period (24-Jul-2013 to 29-May-2015). The floats were ballasted to drift at a target depth of 500m, recording pressure, temperature, and Times Of Arrivals (TOAs) every six hours or every 12 hours.
  • Dataset
    Data and numerical methods for determining the dynamics and kinematics of Newark Bay, NJ
    ( 2019-07-30) Corlett, W. Bryce ; Geyer, W. Rockwell ; Chant, Robert J. ; Ralston, David K. ; Sommerfield, Christopher K.
    These observational data and numerical methods were used to investigate the subtidal salt balance of Newark Bay, a sub-estuarine network connected to the Hudson River estuary through New York Harbor. The moored data were collected in 2008 by Chant and Sommerfield, and in 2016 by Corlett, Geyer, and Ralston. Corlett devised the included numerical methods. Shipboard measurements of the vertical salinity profile near each mooring were used to reconstruct the tidally-varying vertical salinity profile from near-bed and near-surface salinity measurements at each mooring. The effects of tidal processes, such as frontal advection, on the exchange flow were investigated by applying the isohaline total exchange flow (TEF) framework to the mooring-based observations in multiple reaches of the estuarine network. In addition, a TEF-based salt balance was derived for the purpose of directly comparing the TEF framework with the standard Eulerian framework.
  • Software
    Seamount- or Lake/Basin-trapped waves with stratification, topography, mean flow and bottom friction in Matlab
    ( 2018-08-17) Brink, Kenneth H.
    This set of Matlab mfiles (all having names that begin with “bigs”) can be used to calculate seamount-trapped (or basin-trapped) wave modal structures and dispersion curves under very general circumstances. A complex frequency is allowed, so that instability and damping can be accounted for directly. Modal structures and energy diagnostics are provided. For most applications, the code is only useful for subinertial wave frequencies (i.e., the real part of wave frequency is smaller than the Coriolis parameter). For interpreting the model results, see Brink (1989), which deals with the case with no mean flow or finite bottom friction. The present code was developed independently of the Fortran code used in that publication.