What are coastal landscapes used for?

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The Baltic Sea in the Holocene

The Baltic Sea is a young sea whose current shape only emerged when the Nordic inland ice melted. The continuous melting of the ice caused the sea level to rise, so that a connection to the ocean was established via the Central Swedish Depression. From the Baltic ice lake of the last ice age, the marginal sea, the Baltic Sea, developed in different phases. The sea level has risen by around 2 mm / year to this day and leads to transgression, i.e. the sea spills over onto the mainland. This process cannot be explained by the melting of the ice alone. Isostatic processes should be mentioned as a further cause (Neumann-Meyer 1996). If the continental plates had been forced to sink under the ice sheet, a countermovement set in with the relief due to the melting of the ice. Scandinavia and the north-eastern coastal area are still rising by several millimeters per year. As an isostatic compensation process, the south-western coast of the Baltic Sea sinks by about one millimeter per year (Meyer & Schilke 1993).

Due to the uplift in Scandinavia, the connection to the ocean via the Central Swedish Depression was lost. The Baltic Sea became a freshwater lake. As a result of the subsidence in the south, salt water was increasingly able to penetrate into the Baltic Sea via the Great, and later also via the Little Belt and the ├śresund. As the sea level rise stagnated, these connecting routes also became flatter and narrower. This reduced the water exchange with the ocean, so that the Baltic Sea today has only half the salinity of the ocean.

The basis for the diversity of forms on the Baltic coasts was laid by land uplifts and subsidence, sea level rise and the reshaping of the landscape by ice and meltwater. The actual shaping of these landscapes between the mainland and the sea, however, as on all coasts of the sea, was taken over by water and wind. In doing so, they made a significant contribution to the design of the various coastal forms.