University of Gothenburg
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Pipes for surface sea water and from deeper down, as well as compressed air
Sea water from 1.4 metres depth and from 45 metres depth are available in many labs
Photo: Martin Larsvik
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Sea water systems

Through-flowing filtered sea water is one of the most important facilities at Tjärnö Marine Laboratory. We have deep water, with relatively high and stable salinity, and surface water, in which both salinity and temperature varies. Thanks to water reservoir and alarm to caretaker, the sea water systems are quite reliable.

For both deep and surface water entering the Tjärnö Lasse lab, salinity and temperature are continuously measured. It can be seen on the Water and weather data web page.

Deep water

The water intake is at 45 metre depth. In the Pump House incoming water is flowing through a 10 mm coarse sieve and is pumped through filter with sand in three layers (6-8 mm, 3-4 mm and 1-2 mm) to the water reservoir above White Residence. From there the water flows to the Education Building, Lars Afzelius' Laboratory, White Laboratory, Yellow Laboratory and Ecotron. In total there are deep or surface water available from about 800 taps. Compiled measurement results from 2009-2018 are shown in diagrams below.

Diagram showing salinity variation over the year in deep water at Tjärnö Laboratory
Salinity of deep water in the laboratories, mean (bold line) with 95% confidence interval (blue). Highest and lowest measured values are 35.2 ‰ and 28.6 ‰, respectively.
Photo: Martin Larsvik
Diagram showing temperature variation over the year in deep water at Tjärnö Laboratory
Temperature of deep water in the laboratories, mean (bold line) with 95% confidence interval (blue). Highest and lowest measured values are 16.9 °C and 2.2 °C, respectively.
Photo: Martin Larsvik

Surface water

In frost-free season (often April-November) there is through-flowing surface water. It is pumped from 1.5 metre depth. The pump is protected by a 2 mm filter, but otherwise there is no filtering. Water can be cooled to 4 °C, and heated to 30 °C. Surface water is available in Education Building, Lars Afzelius' Laboratory, Yellow Laboratory and Ecotron. In total there are deep or surface water available from about 800 taps. Compiled measurement results from 1980-2013 are shown in diagrams below.

Diagram showing salinity variation over the year in surface water at Tjärnö Laboratory
Salinity at 1 metre depth in the sea by the surface water intake, mean (bold line) with 95% confidence interval (blue). Highest and lowest measured values are 34.5 ‰ and 9.3 ‰, respectively.
Photo: Martin Larsvik
Diagram showing temperature variation over the year in surface water at Tjärnö Laboratory
Temperature at 1 metre depth in the sea by the surface water intake, mean (bold line) with 95% confidence interval (blue). Highest and lowest measured values are 24.1 °C and -1.5 °C, respectively.
Photo: Martin Larsvik