The Global Sea Level Observing System

Data

GLOSS Sea Level Data

Data from GLOSS stations contribute to many sea level data centres and programmes. An overview of the various programmes is available.

(1) Obtain Mean Sea Level (MSL) data from the PSMSL
GLOSS was originally proposed in order to improve the quantity and quality of Mean Sea Level data supplied to the Permanent Service for Mean Sea Level (PSMSL), and GLOSS continues to perform that function. Time series plots of GLOSS station data obtained from the PSMSL RLR database are also available.
(2) Obtain high frequency delayed-mode data from the GLOSS Station Handbook
The supply of MSL data to the PSMSL is not now the ONLY requirement of a country participating in GLOSS. The Implementation Plan 1997 specifies requirements for the free exchange of the original (typically hourly) sea level data in delayed-mode to an International Sea Level Centre. To check the availability of original delayed-mode sea level data from GLOSS sites, see the information for each site contained within the GLOSS Station Handbook.
(3) Obtain high frequency fast-mode data from UHSLC (or via DODS server)
For FAST sea level data from GLOSS sites (i.e. data availability within a week or so), see the contents of the GLOSS Fast Data Center at the University of Hawai`i Sea Level Center.
(4) Obtain high frequency real time/near real time data from the sea level station monitoring facility
For real time/near real time sea level data from GLOSS sites (data available within minutes, to several hours), see the sea level station monitoring facility.
(5) Africa and Western Indian Ocean sea level data
For high frequency delayed-mode data from ODINAFRICA and Western Indian Ocean tide gauges.

GLOSS Sea Level Data Quality Control

The issue of Quality Control (QC) is the main reason why we now require that original GLOSS sea level data, as well as the monthly and annual means, be sent to an international centre. (In addition, there is of course much interesting oceanography to be studied with the higher frequency data and all data should be preserved in several centres for long term security.) QC for GLOSS data is addressed in several ways:

• In the IOC Manuals on Sea Level Measurement and Interpretation (Manuals and Guides No.14, 4 volumes).

• In the software packages for tidal analysis available from the University of Hawai`i, the Australian National Tidal Facility and the Permanent Service for Mean Sea Level.

• 'Developments in Sea Level Data Management and Exchange' (6.38 MB) by Lesley Rickards (BODC) and Bernard Kilonsky (UHSLC). This paper was presented at the Ocean Data Symposium, Dublin, Ireland (October 1997) and describes the QC methods followed for data banking of WOCE sea level information, which are essentially those to be followed for GLOSS.
  

GLOSS/IODE Sea Level Data Archaeology Project

In 2001 GLOSS and IODE initiated a Data Archaeology Project, coordinated by Dr. Lesley Rickards, aimed at the data rescue of sea level information available so far only in paper form (charts, paper tape etc.) and its conversion into computer-accessible form.

For more information on the project, you can read the letter (32 KB) that was circulated to the GLOSS contact list and to the IODE address list, requesting all countries to assess their holdings of historical tide gauge data which can potentially be rescued.

To provide information to the project, please download and complete the questionnaire in

• Adobe Acrobat format (19 KB)
• Microsoft Word format (38 KB)

Completed questionnaires have been received from

• Australia (65 KB)
• Belgium (47 KB)
• Greece (30 KB)
• Israel (53 KB)
• Italy (46 KB)
• Malta (44 KB)
• Netherlands (54 KB)
• Peru (193 KB)
• Turkey (88 KB)

If organisations need help in converting their paper records into computer form, they should contact either the GLOSS Technical Secretary or the PSMSL.

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