New buoys conquer waves to understand out seas
11th June 2008
A pair of bright yellow, 7 metre tall data buoys, bristling with
sensitive instruments will be positioned in the seas off Plymouth
this week, as part of the £100m national marine science programme
Oceans 2025, funded by the Natural Environment Research Council
(NERC). The “state-of-the-art” data buoys were built by local
engineering company Hippo Marine at Saltash, Cornwall for PML. The
buoys will transmit data back to PML as part of the Western Channel
Observatory (WCO), and provide an unprecedented level of detail to
help marine scientists understand how our coastal seas work.
Team leader Dr Tim Smyth explained: “The existing data has
provided a fascinating long term understanding, going back at one
of the sites for over a century, but if we are to manage our seas
more scientifically and sustainably we need the detail - and that’s
what these buoys will give us. One of the buoys will be in an area
much closer inshore where the effects of estuarine waters will be
seen, the other is further out and in very different conditions. Up
to now we have relied on data collected once a week at best, from a
boat visiting the two sites. Now we can get data as it happens, so
we can look at the small scale changes and see how they in turn
affect the longer term. For example, on the one hand we can
establish an accurate baseline for studying how humans are
affecting the oceans and the planet through climate change, on the
other we can begin to predict plankton levels within a year time
period and hence the success or failure of fish spawning and
ultimately the productivity of our coastal waters.”
The specially designed data buoys carry an impressive array of
equipment to monitor a wide range of factors including temperature,
salinity, nitrate levels, sediment concentrations and the density
of plant plankton. It is the variety of instrumentation the buoys
carry that makes them unique, and as new questions about the
chemistry and physics of the sea arise and new methods of study are
developed the buoys provide the perfect platform, being both
durable and flexible, ensuring they have a long working life,
powered by a combination of solar panels and wind generators.
Tim Smyth continued; “The buoys are unique in another respect.
The sea conditions are very harsh with waves up to 6 metres,
extremely strong winds and a lot of boat traffic – The English
Channel is a very hostile and very busy place. Existing designs
would simply not survive so we went back to the drawing board and
working with Plymouth company, Hippo Marine, we are confident that
we have a platform that will stand up to the conditions and allow
the delicate equipment to take the sensitive measurements we need;
we have used a ‘moon pool’ to enable the instruments to be lowered
through the centres of the buoys, that way they will always remain
submerged and working. The tethering of the buoys has also given us
a challenge – they have to be kept on station and facing in a
constant direction - each of the buoys weighs around 3.5 tonnes –
to ensure the Internet Broadband and UHF radio links remain
connected. Our colleagues at the Rame Head Coastguard Station have
been very helpful in providing a communication link between PML and
the buoys.”
The WCO is fast becoming one of the most comprehensive data
gathering initiatives in European seas and the scientists at PML
will be making real-time meteorological and oceanographic data from
the buoys available to fishermen, yachtsmen and the wider public
over the internet.