For more than six decades, the Boknis Eck marine observatory has taken oceanic measurements in the Baltic Sea – until recently. Last month, transmissions suddenly and unexpectedly stopped. Now, researchers are looking for clues after they dispatched divers to the seafloor only to find the remote sensors responsible for taking data measurements have been “forcibly removed”.
"On August 21 at 8.15pm it stopped the data transmission," said Boknis Eck coordinator Hermann Bange from GEOMAR in a statement, adding that at first his team suspected a “transmission error,” but divers discovered a much more grim situation when they reached the seabed where the sensors were supposed to be.
"When the divers reached the bottom of the sea last week at the observatory's location, they found only the torn off land cable. It was completely shredded,” said Bange.
Every month since 1957, scientist have been measuring environmental data like temperature, salinity, nutrients, chlorophyll, and oxygen in the precise location of Eckernförde Bay off Germany's Baltic coast, giving researchers a deeper understanding of environmental conditions in the southwest Baltic Sea. Bocknis Eck is one of the oldest, still active marine science sites in the world. In December of 2016, the GEOMAR Helmholtz Center for Ocean Research Kiel and the Helmholtz Center Geesthacht installed an underwater observatory in a restricted area that took additional measurements like flow velocity and methane concentrations along the seabed.
The items that have disappeared were two desk-sized racks weighing 250 kilograms (550 pounds) and 100 kilograms (220 pounds), respectively. One was meant to supply power to the monitoring station via a cable connected to the land while a second housed the sensors. Given their large and cumbersome size, scientists haven't ruled out that they may have been ripped away by storms, currents, or large marine mammals, though experts say it is unlikely.
Police are investigating the disappearance of the equipment quoted at around €300,000, but Bange says the data it provides is “priceless”.
"At first, we tried to find the devices with our own research and other diving applications. So far without success. That's why we would be very happy about any hints,” he said, adding that there is a chance someone may have seen something at a nearby campsite on August 21, or perhaps someone may have found parts of the frames somewhere on the beach.
Researchers are working to get the “observatory back up and running as quickly as possible”.