Details of Ross Ice Shelf Cavity Ocean Data


Dataset identification

Title of datasetRoss Ice Shelf Cavity Ocean Data
Narrative summary of datasetHere we provide data from the Ross Ice Shelf ocean cavity.  Location  -  The HWD2 Camp was established in October of 2017 at 80o 39.497’S, 174o 27.678’E where the ice is moving seaward at around ~600 m a-1 and is sourced from the Transantarctic Mountains.  Profiling Instruments -  Profiling was primarily conducted with an RBR Concerto CTD (conductivity-temperature depth) profiling instrument, and this was cross-calibrated against irregular profiles with an RBR Duet (pressure and temperature only), a SBE37 MicroCat CTD as well as moored SBE37 MicroCat CTDs.  The RBR unit is small and has suitable sensor capability (temperature and conductivity accuracies of ±0.002°C and ±0.003 mS cm-1).  Its conductivity cell design is not prone to fouling by ice crystals, making it ideal for work in the sometimes crystal-laden borehole conditions.   We were inconsistent in how we mounted the CTD on its protective frame and this appeared to make small difference in the conductivity signal (resulting in an ~0.03 psu variation).  This was post-corrected based on the essentially invariant mooring data from the lower water column as well as SBE37 cross-calibration profile data. Because of the potential for sediment contamination of the sensors, the profiles were mostly conservative in their proximity to the sea floor. On several occasions, profiles were conducted all the way to the sea floor. The temperature and salinity are presented in EOS-80 in order to compare with available data.  Eighty three profiles are provided here (ctd_HWD2_*.dat). In addition, limited microstructure profiling was conducted to provide insight into some of the mixing details. The profiles were conducted by lowering the instrument to the ice base then commencing a sequence of three up-down “yo-yos” before returning to the surface and downloading. A data segment is included here (VMP_HWD2.dat). There were some challenges registering the vertical coordinate for the profiles.  The melting of the borehole generates a trapped pool of relatively fresh water.  The interface between this and the ocean should be near the base of the hole or a little higher – with seawater intrusion.  However, there were some instances where the interface was at a higher pressure (i.e. apparently in the open water column). The best explanation for this is that the water in the borehole is not at static equilibrium for some period after initial melting. We use 34.3 psu as a cut-off, in addition to a pressure criterion to identify the top of the useful oceanic profile.  It is also not inconceivable that water was being ejected from the hole, but it is unlikely that this would have impacted in the consistent observed pattern.  Instrumented Mooring - The mooring instruments at HWD2-A comprised 5 Nortek Aquadopp single point current meters in titanium housings reporting to the surface (30-minute interval, Table SI-Three) via an inductive modem to a Sound-9 data logger and Iridium transmitter. The current meter measurements were corrected to account for the 138o magnetic declination offset (i.e. the south magnetic pole is to the north-west of the field site).  Five files are provided here (HWD2_Init_rcm*.dat4).  Details in: Stevens C, Hulbe C, Brewer M, Stewart C, Robinson N, Ohneiser C and Jendersie J, 2020. Ocean mixing and heat transport processes observed under the Ross Ice Shelf controls its basal melting, accepted PNAS, May 2020. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.
Start date2017-12-03
End date2018-02-27

Responsible organisations

Organisation nameIfremer, Scientific Information Systems for the sea
Role of organisationDataset Holding Organisation
Organisation nameSEA scieNtific Open data Edition
Role of organisationPublisher
How to citeStevens Craig, Brewer Mike, Grant Brett (2017). Ross Ice Shelf Cavity Ocean Data. SEANOE.

Dataset availability

Original dataset download link
Date of original dataset publication2020-12-13
Dataset formatASC
Public accessNo limitations
License for useCC-BY 4.0
Link to dataset after processing by data


Latitude north boundary-80.64
Longitude east boundary174.2
Latitude south boundary-80.66
Longitude west boundary174.4
Sea areaRoss Sea
Vertical extent minimum325 Metres
Vertical extent maximum620 Metres

Data types, collection and processing

Observation typeWater column temperature and salinity
ParameterSalinity of the water column
Temperature variation in the water column
Horizontal velocity of the water column (currents)
Temperature of the water column
Instrument typecurrent meters
Instrument nameNortek Aquadopp 6000 3D Doppler current meter
Instrument typeCTD
Instrument nameRBR Concerto CTD
Platform typeice shelf
Platform nameHWD2 Camp
Data quality processing informationProcessed data

Process information

Submitting organisationNational Institute of Water and Atmospheric Research
Submission identifier (UUID)a53ad03f-3734-7343-3431-000000074128
Date of dataset creation2017-12-01
Date of dataset revision2020-06-05
Date of metadata creation2020-6-10
Date of metadata latest revision2020-11-26
Date of publishing2020-12-14
Date of processed dataset publication2022-10-14
Processing data centreIfremer, Scientific Information Systems for the sea
Summary record-ID726