GEOMAR and Helmholtz Center Geesthacht install new sensor node in Baltic Sea
Boknis Eck(Boknis Corner) – a name familiar to oceanographers and
marine researchers worldwide.
Since 1957, data on the state of the
Baltic Sea have been collected in the Eckernforde Bay, making Boknis
Eck one of the oldest active time series stations in the world. To
measure shorter-term processes in the seawater, the GEOMAR Helmholtz
Center for Ocean Research Kiel and the Helmholtz Center Geesthacht have
installed a fixed measuring station on the seafloor 14.5 metres deep s.
The Boknis Eck Node started operating at the turn of this year.
How much is the oxygen level of the seawater? What is the temperature
range? What nutrients have been dissolved in the seawater and in what
quantities? How extensive is the growth of plankton? Knowing the
answers to these questions allow the state of the marine ecosystem to
For nearly 60 years, marine researchers at Kiel have been
making their way to Eckernforde Bay to collect such data. This makes
Boknis Eck one of the world's oldest active marine time series
“Thanks to the long period of measurements, we can not only
see the current state of the Baltic Sea, but we also detect long-term
environmental changes. This is why the Boknis Eck dataset is very much
sought after internationally,” said GEOMAR's Prof Dr Hermann Bange in
German. He has been coordinating the activities at Boknis Eck since
Recent studies have shown that even very short-term events like a
two-week heat spell or a single powerful storm could cause a
significant impact on an ecosystem.
“Such events could not be measured
with monthly sampling. That's why we decided to install a permanent
station at Boknis Eck,” explained Professor Bange. And now, after two
years of planning and construction, the new station has started
operations in the Baltic Sea.
The Boknis Eck Node was developed as part of the COSYNA project
(Coastal Observing System for Northern and Arctic Seas) which is being
coordinated at the Helmholtz Center Geesthacht (HZG). Anchored at the
bottom of the Baltic Sea, it contains sensors that measure flow
velocities and directions, salt content, temperature as well as the
concentrations of oxygen, carbon dioxide and methane.
“This makes the
monthly measurements at the Boknis Eck Node time station perfect. We
can add more sensors at any time if necessary,” said Professor Bange.
Within the COSYNA project, the HZG has set up similar underwater
observatories before. “There is already one before Helgoland and one
off the coast of Spitzbergen, which we have developed in cooperation
with the Alfred Wegener Institute,” explained Dr Holger Brix,
co-ordinator of COSYNA at the HZG. “They all offer access to power and
data links, as well as the new measurement station in Boknis Eck, and
are connected to a land-based server via fibre optics. This allows us
to access the sensors at any time, from anywhere in the world.”
Professor Bange added that the data they collect is accessible to all
scientists worldwide, at www.bokniseck.de and www.cosyna.de.