Welcome to the WOCE Sea Level Data Set (Version 3.0, August 2002) ================================================================= Responsibility for data management of the in-situ sea level data set for the World Ocean Circulation Experiment (WOCE) has been jointly vested in the University of Hawaii Sea Level Center (UHSLC) and the British Oceanographic Data Centre (BODC). The two centres perform complementary activities, with the UHSLC acting as the 'fast delivery' centre, providing rapid access to data for those involved in satellite altimetry, and BODC as the 'delayed mode' centre, providing the fully quality controlled comprehensive data set at the end of the project. This disk was produced by the British Oceanographic Data Centre (BODC) with contributions from the Permanent Service for Mean Sea Level (PSMSL), and Laboratoire d'Etudes en Geophysique et Oceanographie Spatiales (LEGOS). To view the data from within an html capable browser, provide the browser with the location of either the 'welcome.htm' or 'index.htm' file in the root directory. If you have Internet access through your browser, you can access the WOCE Sea Level DAC Web pages directly. If you do not have a browser, the data files will still be accessible. They, and the other contents of the CD-ROM are described in more detail below. The following data sets are included on the CD-ROM: 1. WOCE 'Delayed-mode' Sea Level Data Set Directory: del_mode This section of the CD-ROM contains the WOCE 'delayed-mode' sea level data set. In addition to the sea level data measured from coastal tide gauges, data from bottom pressure recorders are also included. Further details of the data files can be found in the 1readme.txt in the del_mode directory. There are 3 sub-directories as follows: ascii The ascii directory contains files which have physical units, and have undergone quality control. In BODC terms they will have been flagged to indicate null, suspect, or interpolated values, and also datum changes. But no data values will have been changed without the permission of the data collector. The files in the ascii directory have been zipped using the UNIX zip utility. zip is a compression and file packaging utility for UNIX, VMS, MSDOS, OS/2, Windows NT and Macintosh, and is compatible with WinZip and PKZIP (Phil Katz's ZIP for MSDOS systems). If the files are unzipped on UNIX, the -a option should be used to get the correct carriage return/line feed end of record sequence. There is an Info-Zip Web site at: http://www.freesoftware.com/pub/infozip, and the software can be downloaded from: ftp://ftp.freesoftware.com/pub/infozip. Once unzipped, ascii filenames are of the form bnnnnnnn.lst, where nnnnnnn is the BODC Series Reference number. For each tide gauge record there is an inventory file indicating which data series relates to which time period - they are generally annual files. The inventory filename is of the form: igmmmmx.txt, where mmmm indicates the GLOSS 3 digit number) or the WOCE (4 digits) number, preceded by g or w. The x indicates different sections of the record where they are not linked to the same datum. These are in BODC Request format (ASCII), a description of which can be found in the del_mode directory, in the file format.htm. Data documentation is also available as ASCII files. netcdf The data are the same as above, but in netcdf format. More information about netcdf is available in the netcdf primer folder. Two routines have also been supplied 'read_ssl.f' (Fortran) and 'read_ssl.m (Matlab) to aid reading the netcdf files. These data have also been zipped (as above). Once unzipped, the netcdf filenames are of the form igmmmmx.txt, where mmmm indicates the GLOSS or the WOCE number, preceded by g or w. The x indicates different sections of the record where they are not linked to the same datum. The individual annual files have been combined into a single file for the data from each site related to a single datum. bpr This directory contains bottom pressure recorder data collected as part of the Proudman Oceanographic Laboratory's ACCLAIM programme. More information about ACCLAIM is given below (Note 3). Data are provided as zipped archives and unzip into files in either netCDF or the BODC Request format (ASCII). The file names are of the form bnnnnnnn.nc or bnnnnnnn.lst, where nnnnnnn is the BODC Series Reference Number. Documentation files are also provided (ASCII); the document indicates to which data series it relates. 2. Tidal Constants from the WOCE Sea Level Data Set Directory: tidalcon Tidal harmonic constants, confidence limits and power spectra have been produced from the WOCE Sea Level Data. These are available from both the 'Fast delivery' and the 'Delayed mode' sea level data sets. This has been contributed by: Frederique Ponchant and Florent Lyard groupe Nivmer Laboratoire d'Etudes en Geophysique et Oceanographie Spatiales (LEGOS) CNES/GRGS UMR 5566 Observatoire Midi-Pyrenees 18, Av. Edouard Belin 31 400 TOULOUSE Cedex France There are two sub-directories, fastmode and del_mode. They each contain ASCII files of tidal harmonic constants (filenames nnnnios.txt), confidence limits (nnnncfd1.txt) and power spectra (nnnnspsd.pdf). The tidal harmonic constants and confidence limits files are ASCII, and the power spectra files are in Adobe Acrobat pdf format. 3. PSMSL Monthly and Annual Mean Sea Level Data Set Directory: psmsl This directory includes the contents of the PSMSL public directory as of August 2002. Updated versions of the contents can be obtained from the web site (www.pol.ac.uk/psmsl). These files are all ASCII. 4. GLOSS Station Handbook (Version 5.0) Directory: glosshb The Global Sea Level Observing System (GLOSS) is a programme coordinated by the Intergovernmental Oceanographic Commission (IOC) for the establishment of global and regional sea level networks. The main component of GLOSS is the 'Global Core Network' of 287 stations around the world for long term climate change and oceanographic sea level monitoring. The GLOSS Station Handbook has been constructed in order to provide further information on each of the tide gauges in GLOSS. This directory contains GLOSS Station Handbook Information Sheets from Version 5.0 (October 2001) of the Handbook, a selection of maps and annual mean sea level plots. Some recently received information may not have been included. The GLOSS Station Handbook is also available on the Web at www.bodc.ac.uk/services/glosshb/glosshb.html. The Information Sheets are ASCII files, and the maps and plots are .gif files. There are also links to sea level data and information available online. --------------------------------------------------------------------------------- Notes: 1. More recent sea level data from the Australian WOCE tide gauges are available from the National Tidal Facility Website at: www.ntf.flinders.edu.au 2. Some files are provided as Adobe Acrobat files (.pdf) which can be viewed with the free Adobe Acrobat Reader. If you do not have this software you can download it directly from the Adobe Acrobat WWW page: http://www.adobe.com/supportservice/custsupport/download.html or install it from the WOCE Data Information Unit CD-ROM. 3. Extra information about the data from the ACCLAIM project The ACCLAIM (Antarctic Circumpolar Current Levels by Altimetry and Island Measurements) programme in the South Atlantic and Southern Oceans consists of measurements from coastal tide gauges and bottom pressure stations, together with an ongoing research programme in satellite altimetry. ACCLAIM is the Proudman Oceanographic Laboratory's main contribution to WOCE (and, in particular, to WOCE Core 2). In Phase 1 of ACCLAIM from 1983, measurements at coastal tide gauge sites took the form of sub-surface pressure (SSP) measurements (units of pressure e.g. mbar) rather than sea level (units of length e.g. centimetres). SSP is here defined as the total, measured pressure recorded by a sub-surface pressure transducer, a measurement which includes the pressure load from the atmosphere as well as from the water column. It is absolutely essential that any user of ACCLAIM data realises which data type (either SSP or sea level) is being analysed. From around early 1993, the gauges at many of the sites were replaced by Phase 2 ACCLAIM `B gauges' which record SSP, air pressure and sea level. The Phase 2 coastal sea level data have precise datum control (see Woodworth et al. 1994 for details) and can certainly be used for long term studies. SSP measurements at deep ocean bottom pressure stations (together with inverted echo sounder and temperature measurements) have also been a feature of ACCLAIM. Note that these are DEEP SEA pressure records, not from coastal pressure sensors, so station names like 'Amsterdam' are just convenient labels. Unless stated otherwise, the datum of each record in each file from the same station (e.g. Amsterdam) should be regarded as being different as it is impossible to deploy a pop-up sensor at exactly the same location. In addition, consideration should be given to the fact that all pressure sensors, especially those at great depths, can be subject to long term drift. ACCLAIM data are only supplied as ASCII files. 4. National Tidal Facility, Flinders University of South Australia SPECIAL NOTE FROM THE DATA CONTRIBUTORS ======================================= Supply of sea level data from the following sites: Bundaberg (Burnett Heads), Casey, Cocos Island (Keeling), Darwin, Davis, Esperance, Fort Denison, Funafuti, Honiara, Lombrum, Majuro, Mawson, Nauru, Nuku'alofa, Port Vila-B, Rarotonga, Spring Bay, Suva, Tarawa-C, Townsville is subject to the following conditions: i) For contractual reasons, the National Tidal Facility needs to know who is accessing the data they supply. In this regard, they need detailed information about the user, their company/research body, the data they access, their intentions for use and details of any publications resulting from that research. ii) When any data supplied by the National Tidal Facility is used in any publication or report, the origin of such data shall be acknowledged in that publication or report in the following approved form :- "Tidal {data} for {port} {are} supplied {constants} {station} {is} {predictions} {....} {material} {....} by the National Tidal Facility, The Flinders University of South Australia, Copyright reserved." iii) All material is supplied in good faith and is believed to be correct. It is supplied on the condition that no warranty is given in relation thereto, that no responsibility or liability for errors or omissions is, or will be, accepted and that the recipient will hold the Flinders University of South Australia and the National Tidal Facility free from all such responsibility or liability and from all loss or damage incurred as a consequence of any error or omission. iv) The acceptance of material and computations from the National Tidal Facility of the Flinders University of South Australia will be deemed to include acceptance of the conditions of supply. --------------------------------------------------------------------------------- For further information contact: Lesley Rickards WOCE 'Delayed-mode' Data Assembly Centre British Oceanographic Data Centre Proudman Oceanographic Laboratory Bidston Observatory Prenton, CH43 7RA United Kingdom Telephone: +44 (0)151 653 8633 Facsimile: +44 (0)151 652 3950 E-mail: ljr@bodc.ac.uk URL: http://www.bodc.ac.uk ACKNOWLEDGEMENTS BODC gratefully acknowledge the efforts of the many organisations and individuals who have made data and information available for the publication of this CD-ROM. Many BODC staff have contributed to the compilation of this data set in a variety of ways, including designing and developing software and quality controlling the data. Particular thanks go to Steve Loch, Elizabeth Bradshaw, Kay Thorne, Sally Dowell and Richard Downer. This DVD set should be referenced as: WOCE Data Products Committee. 2002. WOCE Global Data, Version 3.0, WOCE International Project Office, WOCE Report No. 180/02, Southampton, UK. 22 August 2002