Gotland

Pohl, C., Loffler, A., and Hennings, U. (2004) A sediment trap flux for trace metals under seasonal aspects in the stratified Baltic Sea (Gotland Basin 57° 19.20 N 20°03.00/E). Mar. Chem. 84, 143-160. 

The concentrations of particulate manganese in the layer of its maximum in the central part of the Sea are usually about several tens or hundreds of nM [63,66,68]. They increase to 2-5 xM in the regions that are influenced by the Bosporus and to 1.5-2.0 xM in the connected with the Rim Current eddies [38,60,64]. According to our and other investigations in the Black Sea [60,69] and in the Gotland Deep in the Baltic Sea [70], the concentrations of particulate manganese (and iron) increase in the winter-spring period and decrease in summer. 

The study of the Kymijoki River has indicated that this river has been contaminated tens of kilometers downstream from the manufacturing site with PCDEs as well as with PCDDs and PCDFs originating as impurities from Ky-5 [114]. The concentrations of PCDEs in reference site sediments upstream from the manufacturing site have been low, as well as those in Baltic sediments [33, 113]. PCDE congeners were below 0.4 ng g 1 dw in sediments from the Gulf of Finland, near Gotland and the Bothnian Bay. 

Nausch, G., Matthaus, W., and Peistel, R. (2003). Hydrographic and hydrochemical conditions in the Gotland Deep area between 1992 and 2003. Oceanologia 45(4), 557-569. 

Volkov 1. L, Rozanov A. G., and Zhabina N. N. (1983) Sulfur compounds in sediments of the Gotland Basin (Baltic Sea). Lithology and Mineral Resour. 18(6), 584-598. 

Bottcher M. E. and Huckriede H. (1997) Eirst occurrence and stable isotope composition of authigenic 7-MnS in the central Gotland Deep (Baltic Sea). Mar. Geol. 137, 201-205. 

Burke 1. T. and Kemp A. E. S. (2002) Microfabric analysis of Mn-carbonate laminae deposition and Mn-sulfide formation in the Gotland Deep, Baltic Sea. Geochim. Cosmochim. Acta 66, 1589-1600. 

In the Baltic Sea, the offshore scale for the transition of topography from the coast to the plain areas of the basins is commonly much larger than the baroclinic Rossby radius. Therefore, CTW can be used to analyze the dispersion and modal structure of sea level variations and quasi-geostrophic currents trapped at the basin rim. Some basins do not have well established plains, therefore, in these basins, the eigenvalue problem must be solved for the whole basin diameter, for example, the Eastern Gotland Basin. The CTW structures of both coasts splice each other in the center of the basin. Hence, CTWs are an effective mechanism for the communication between the rim and the center of the corresponding (e.g., Gotland) basin. 

Dissipation measurements in the Eastern Gotland Basin were performed by Lass et al. (2003) during winter stratification in April 1999 and during summer stratification in September 2000. Dissipation profiles were measured about every 10 min over a time interval of about 9 days. This provided a data set that enabled to estimate quite reliable averaged dissipation profiles given the huge intermittency of dissipation in stratified water, see Fig. 2.8. The dissipation decreases from the surface to a depth of about 50 m. Maximum dissipation is observed in the halocline, while it decreases below the halocline to an absolute... 

FIGURE 2.8 Averaged dissipation of turbulent kinetic energy measured in the Eastern Gotland Basin in April 1999 and September 2000. 

Hagen, E., Feistel, R., 2004. Observations of low-frequency current fluctuations in deep water of the Eastern Gotland Basin/Baltic Sea. Journal of Geophysical Research, 109, C03044, doi 10.1029/ 2003JC002017. 

Zhurbas, V. M., Paka, V. T., 1997. Mesoscale thermohaline variabihty in the Eastern Gotland Basin following the 1993 major Baltic inflow. Journal of Geophysical Research, 102(C9), 20,917-20,926. 

The first cmises were limited to sea areas between the Fehmarnbelt and the island of Bornholm until the summer of 1953. Later, some expeditions as forerunners of the seasonal cruises were extended to the Gotland Sea beginning in May 1955 and to the Gulf of Finland beginning in November 1955. The transition area between the North Sea and the Baltic was included in March 1959 by measurements with r/v Joh. L. Kruger in the Kattegat and the Skagerrak. 

FIGURE 3.1 Monitoring station network of the IfM in 1980 and of the lOW in 2005, the first IfM buoy station in 1964, and the MARNET stations. Lower right comer bathymetric map of the central Eastern Gotland Basin with positions of the central BMP station (271) and moored subsurface strings between 1993 and 2005 used abbreviations and further details are compiled in Table 3.3. 

Due to the great success of the IBY, the Baltic oceanographers recommended at the conference in Helsinki in 1970 the voluntary continuation of the IBY programme for the subsequent years. The GDR followed this recommendation. In combination with the national monitoring programme covering the Baltic Sea between Fehmarnbelt and Bornholm Basin, the IfM Warnemunde expanded its seasonal cruises to the Gotland Deep... 

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