Aurora Australis Southern Ocean oceanographic data, voyage 1, 2002-2003 - ADCP data

As this metadata record was completed by AADC almost twenty years after data collection, guarantees cannot be made as to the data quality. See the readme files in the downloads for more information. Oceanographic measurements conducted on voyage 7 of the Aurora Australis of the 2002-2003 season. The...

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Bibliographic Details
Other Authors: AADC (originator), AU/AADC > Australian Antarctic Data Centre, Australia (resourceProvider)
Format: Dataset
Language:unknown
Published: Australian Ocean Data Network
Subjects:
AMD
Online Access:https://researchdata.ands.org.au/aurora-australis-southern-2003-adcp/1461860
https://data.aad.gov.au/metadata/records/au0201
https://data.aad.gov.au/eds/5104/download
https://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=au0201
Description
Summary:As this metadata record was completed by AADC almost twenty years after data collection, guarantees cannot be made as to the data quality. See the readme files in the downloads for more information. Oceanographic measurements conducted on voyage 7 of the Aurora Australis of the 2002-2003 season. These data are ADCP (Acoustic Doppler Current Profiler) data. These data were collected/collated by Mark Rosenberg. Final ADCP data for voyage au0201 (SAZ mooring turnaround and iceberg B9B experiment), Aurora Australis Voyage 1 2002/2003, 17th Oct 2002 to 18th Nov 2002. * The complete ADCP data for cruise au0201 are in the file: au020101.cny (ascii format) a0201dop.mat (matlab format) * The "on station" ADCP data (specifically, the data for which the ship speed was less than or equal to 0.35 m/s) are in the files: au0201_slow35.cny (ascii format) a0201dop_slow35.mat (matlab format) * The file bindep.dat shows the water depths (in metres) that correspond to the centre of each vertical bin. * The data are 30 minute averages. Each 30 minute averageing period starts from the time indicated. (so, e.g., an ensemble with time 120000 is the average from 120000 to 123000). * ADCP currents are absolute - i.e. ship's motion has been subtracted out. * Note that the top few bins can have bad data from water dragged along by the ship. * Beware of data when the ship is underway - it's often suspect. MATLAB VECTORS AND MATRICES: ============================ header info --- for header info: column number corresponds to 30 minute average number botd = mean bottom depth (m) over the 30 minute period cnav = GPS info: don't worry about it cruise = cruise number date = ddmmyy (UTC) ibcover = a bottom track parameter: don't worry about it icover = percentage of 30 minute averageing period covered by acceptable 3 minute ensembles lastgd = deepest accepted bin in this profile lat = mean latitude over the 30 minute period (decimal degrees) lon = mean longitude over the 30 minute period (decimal degrees) nbins = no. of bins logged (=60) shipspeed = scalar resultant of shipu and shipv shipu = ship's E/W velocity over the ground over 30 minute period (m/s, +ve east) shipv = ship's N/S velocity over the ground over 30 minute period (m/s, +ve north) time = hhmmss, time (UTC) at start of 30 minute averageing period dectime = time in decimal days from start of year 2002 (e.g. midday on January 2nd = 1.5000) adcp data --- for adcp data matrices: row number corresponds to bin number column number corresponds to 30 min. average no. bindep = depth (m) to centre of each bin in the profile (will be the same for all profiles) ipcok = percentage of the profile period for which there was good data in this bin (N.B. data=NaN when ipcok=0) qc = a quality control value for each bin - see below speed = scalar resultant of u and v u = east/west current (m/s, +ve east) v = north/south current (m/s, +ve north) ASCII FORMAT FILE: ================== * The file starts with a 3 line header. * Then comes each 30 min. ensemble, as follows: First, a 1 line header, containing date (UTC) (dd-mmm-yyyy) time (UTC) (hh:mm:ss) % of 30 min average covered by acceptable 3 min. ensembles deepest accepted bin in the profile ship's E/W velocity over the ground over the 30min (m/s) ship's N/S velocity over the ground over the 30min (m/s) P= GPS position-derived velocity (D=direct GPS vel.; B=bottom track vel.) mean longitude over the 30 min. mean latitude over the 30 min. % of interfix period for which there was bottom depth information mean bottom depth over the 30 min. 0 0 Next, the data, from the shallowest bin to the deepest bin: for each bin, there's 4 parameters: u = east/west current (m/s, +ve east) v = north/south current (m/s, +ve north) qc = quality control value - see below ipcok = percentage of the profile period for which there was good data in this bin Note that the data are written left to right across each line, then onto the next line, etc. (so 4 bins on a full line) quality control value: --- qc = %good / (Verr+0.05) where: %good = percent good pings after logging system screening Verr = RMS error velocity (m/s). Possible range of qc is 0-20, with an expected range of 0-10; values of 0-4 indicate very poor data; values above 8 indicate very good data.