Lovisa and Anna when they arrive at Ocean Surveyor

Today, Anna and I (Lovisa) are on our way from our work place (Geological Survey of Sweden or SGU) in Uppsala to the vessel Ocean Surveyor. We are travelling by train up north along the Swedish east coast to the city of Härnösand, where Ocean Surveyor is waiting for us. The coming week we will work, live, sleep and eat on the vessel. SGUs Ocean Surveyor is a specially equipped vessel that we use to obtain data concerning seabed composition and appearance. It is equipped with various hydro acoustic systems, such as, echo sounders, seismic and side scan sonar (i.e. lots of buttons to press). We also use massive of cool coring equipment to recover sediments (mud) from the sea floor. In addition, we have an underwater video camera that we use to take images of the sea floor.

Anna, I, and the rest of the crew have a very important task to fulfil this week. We have to collect a lot of mud to be analysed for their content of pollutants (toxins) e.g. cadmium (Cd), mercury (Hg), dioxins and PCB. These pollutants mainly originate from old paper mills along the north Swedish east coast. This area was, and to some extent still is, the centre for cellulose production in Sweden and large amounts of toxins have been released over the last c. 100 years. Pollutants and fibrous material have accumulated on the sea floor and formed large bank deposits of stinky and gooey mud. Due to the continuous and rapid land uplift, these shallow banks may soon be exposed to current and wind erosion. Such a scenario would spread pollutants that currently are buried in the sediments and there is a great that would be distributed into the water and into the food chain. To gain more information about the fibrous banks (their size, distribution, volume, pollutant content etc.) SGU is surveying the sea floor along the coast. The aim is to reveal old sins of pollution.