The African Sea Level Network.
survey of the status of the African Sea level network was undertaken in
2005 in order to select potential locations for installation of new tide
gauges, and also to assess which existing equipment required upgrade. This
was done on the basis of a questionnaire sent to national contacts, as
well as reports from previous surveys (GLOSS, GOOS Africa). The survey
revealed the existence of at least 40 operational stations spread unevenly
along the African coastline and island states. In the Indian several
stations installed by the University of Hawaii within the framework of the
TOGA project are still functioning. South Africa has an extensive network
of gauges along its coastline. Other countries that have established
national tide gauge networks include Morocco, and Mozambique. Large
stretches of coastline did not have any operational gauges. There were
gauges at eight (8) locations which were not working. Only two stations in
the entire network met the specifications for tsunami early warning system
(Rodrigues and Port Louis, both in Mauritius). The most common model of
installed tide gauge was the OTT float gauge, followed by Handar encorders
at stations that are installed and maintained by the University of Hawaii
Sea Level Centre in the Indian Ocean.
Timelines for installation of GLOSS stations along Africa coastline
sites for installation of new tide gauges.
In preparation for
the installation of ODINAFRICA tide gauges, technical visits were
undertaken to inspect the sites proposed for the installations in:
Reports of other
assessment missions undertaken earlier are also available:
New tide gauges by ODINAFRICA.
New tide gauges
have now been installed at the following locations by ODINAFRICA:
The ODINAFRICA Sea
Level station configuration consists of (i) A Kalesto radar gauge; (ii)
two pressure sensors; (iii) a Logosens-2 datalogger; and (iv) an OTT HDR
DCP satellite transmitter for the Meteosat.
In addition the
following sea level stations have been upgraded within the framework of
the Indian Ocean Tsunami Early Warning and Mitigation System: Mombasa and
Lamu (Kenya), Zanzibar (Tanzania), Pointe La rue (Seychelles), Rodrigues
and Port Louis (Mauritius).
New stations have
been installed at Inhambane and Pemba (Mozambique) within the framework of
the GLOSS programme.
ODINAFRICA has established collaboration with the Permanent Service for
Mean Sea Level, Indian Ocean Tsunami Warning and Mitigation System, SHOM
and Benguela Current LME project to ensure that there is a more
comprehensive network of evenly spaced sea level stations, providing data
near real-time, and addressing the key oceanographic phenomena along the
African coastline. Other stations that will be installed/upgraded within
the framework of this collaboration include:
(Cameroon), Alexandria (Egypt), Nosy Be (Madagascar), Casablanca
(Morocco), Dakar (Senegal), and Cap Bon (Tunisia).
GLOSS will also install satellite transmitters at Simonstown, Port
Elizabeth and Durban (South Africa)
plans to install gauges at Lamberts Bay (South Africa), Luderitz and
Walvis Bay (Namibia), and Namibe and Luanda (Angola).
SHOM –France (3):
plans to instal gauges at Point des Galets-La Reunion, Dzaoudzi- Mayottee
(France), and Tamatave (Madagascar).
Shimoni, Malindi, and Lamu (Kenya), Lagos (Nigeria).