1. Sustaining Tide Gauges Thorkild Aarup IOC

2. Issues for discussion (1/4) Maintain measurements to high quality –Tide staff readings (local operator) –QC/QA of readings (techniques from course) –Leveling (link with national survey institute?) –Submit data to PSMSL/UHSLC Keep in touch/collaboration - African sea level network operators group? African sea level activity web-site? (http://www.ioc.unesco.org/glossafrica/)http://www.ioc.unesco.org/glossafrica/

3. Role of local tide gauge contacts A tide gauge operator needs to be identified (responsible for all operational requirements e.g weekly tide staff readings, at least annual levelling, routine inspection of equipment, communication with OdinAfrica and other relevant; e-mail tide staff readings to PSMSL/Oostende; metadata provision) UHSLC/Australia/UK use this model sucessfully

4. Issues for discussion (2/4) Ways of sustaining tide gauges with the aim of building a long-term record –Multiple use of data from gauges (Navigational safety, tidal predictions, storm surge/tsunami monitoring, coastal planning & constructions, modeling, long-term sea level change, international regional/global research/monitoring programs & data exchange) –Multiple users can mean multiple advocates! –Free and open access to data from IOC provided gauges has to be guaranteed in accordance with IOC data policy, but products can perhaps generate be provided (i.e. tide tables)

5. Issues for discussion (3/4) The International Hydrographic Organisation (IHO) and the International Association of Marine Aids to navigation and Lighthouse Authorities (IALA) endorse the initiative of OdinAfrica/GLOSS to upgrade tide gauges and recognize the contributions these upgrades can make to improving safety of navigation. Train new people as tide gauge operator when tg operators move on or retire Provide products from TG to community

6. Issues for discussion (4/4) What plans are there for national network maintenance (i.e. Kenya – 3 stations; Mozambique 3-4 stations) ?

8. Role of Oostende facility Data capture via GTS and archive in relational database as an OdinAfrica backup to national and GLOSS data centers Web-display (incl. plots and raw data provision); TG operator alert Perhaps semi-automatic data quality control down the road Perhaps keep communication with technical consultant and perhaps provide line management

9. Overall Quality Assurance Some mechanism is required on site to check that the tide gauge operators/tide staff readers carry out that work to common accepted GLOSS standards. One possibility is a dedicated technical consultant who would visit once per year to also assist with levelling, local training, data quality issues etc. In addition have available a technical node to provide advice wrt. technical issues (tel/e-mail assistance) – POL presently does this. Issues: Cost