One hundred years of hydrographic measurements in the Baltic Sea
In: Journal of Sea Research. Elsevier/Netherlands Institute for Sea Research: Amsterdam; Den Burg. ISSN 1385-1101; e-ISSN 1873-1414, more Also appears in:Ohlson, M.; Omstedt, A.; Turner, D. (Ed.) (2003). Proceedings of the 22nd Conference of the Baltic Oceanographers (CBO), Stockholm, Sweden, 25-29 November 2001. Journal of Sea Research, 49(4). Elsevier: Amsterdam. 227-374 pp., more |  |
| Keywords | Chemical compounds > Nitrogen compounds > Nitrates
Chemical compounds > Phosphorus compounds > Phosphates
Chemical elements > Nonmetals > Atmospheric gases > Oxygen > Dissolved gases > Dissolved oxygen
Properties > Chemical properties > Alkalinity
Properties > Chemical properties > Salinity
Properties > Physical properties > Thermodynamic properties > Temperature
Surveys > Hydrographic surveys
Time series
Water > Deep water
Water > Stagnant water
ANE, Baltic, Bornholm Basin [Marine Regions]; ANE, Baltic, Bothnia Gulf [Marine Regions]; ANE, Baltic, Gotland Deep [Marine Regions]; ANE, Baltic, Landsort Deep [Marine Regions]
Marine/Coastal | | Author keywords | Baltic Sea; hydrographic parameters; nutrients; long-time series;Gotland Deep; stagnation |
| Authors | | Top | - Fonselius, S.
- Valderrama, J., correspondent
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| Abstract | The first measurements of salinity of the deep water in the open Baltic Sea were made in the last decades of the 1800s. At a Scandinavian science meeting in Copenhagen in 1892, Professor Otto Pettersson from Sweden suggested that regular measurements of hydrographic parameters should be carried out at some important deep stations in the Baltic Sea. His suggestion was adopted and since that time we have rather complete hydrographical data from the Bornholm Deep, the Gotland Deep, and the Landsort Deep and from some stations in the Gulf of Bothnia. The measurements were interrupted in the Baltic Proper during the two World Wars. At the beginning only salinity, temperature and dissolved oxygen were measured and one or two expeditions were carried out annually, mostly in summer. In the 1920s also alkalinity and pH were occasionally measured and total carbonate was calculated. A few nutrient measurements were also carried out. After World War II we find results from four or more expeditions every year and intercalibration of methods was arranged. Results of temperature, salinity and dissolved oxygen measurements from the Bornholm Deep, the Gotland Deep, the Landsort Deep and salinity measurements from three stations in the Gulf of Bothnia, covering the whole 20th century are presented and discussed. The salinity distribution and the variations between oxygen and hydrogen sulphide periods in the deep water of the Gotland Deep and the Landsort Deep are demonstrated. Series of phosphate and nitrate distribution in the Gotland Deep are shown from the 1950s to the present and the effects of the stagnant conditions are briefly discussed. Two large inflows of highly saline water, the first during the First World War and the second in 1951, are demonstrated. The 20th century minimum salinity of the bottom water in the Baltic Proper in 1992 is discussed. |
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