SEAREG – Sea Level Change Affecting the Spatial Development in the Baltic Sea Region
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The project will evaluate the effects of the climate change on socio-economic and natural systems in the Baltic Sea region, with particular emphasis on the sea-level rise and the changing run-off patterns of rivers, as these are factors that can both lead to major flooding events. Such flood events have severe effects on cities and regions as well as ecosystems, and influence the sustainable development of the entire Baltic Sea region. This also affects strategies and concepts in spatial development.
The aim of the project is to assess the most important effects of a change in the sea-level in the Baltic Sea region. To geographically identify the flood-prone areas, the project uses GIS-based methods, in which land uplift and subsidence data can be taken into account in addition to sea-level changes. The results are grid-based cartographic presentations showing the estimated sea-level changes in the next 100 years. In combination with a with a digital elevation model as well as land use and terrain data, the effects and spatial extent of the sea-level changes can be evaluated. The data obtained in the case study areas are entered into a GIS, and the regional, flood-prone areas are marked.
In the project, the regional climate model RCAO comes into use (Rossby Centre Atmosphere Ocean Model - with data from HadAM3H) for the projections of future changes in the sea-level. The three-dimensional high-resolution model takes into account atmosphere, land surface, sea and ice. Four climate scenarios, based on the emission scenarios A2 and B2 of the Intergovernmental Panel on Climate Change (IPCC), are used for assessing the uncertainties in the projections of the future changes in the sea-level.
Sea-level changes between 0 and 80cms, with three different scenarios being applied per case study area: for example, the values for the case study area of Itä-Uusimaa in Finland were +70 to +75cms in the "high" scenario, +20 to +25cms in the "medium" scenario and -22 to -27cms in the "low" scenario (with the decrease due to projected land uplifts). For the case study area of Pärnu, Estonia, the values ??are +5cms (low), +52cms (medium) and +104cms (high), relative to the annual mean water level for the period 1961-1990. As far as the river run-off patterns are concerned, a general trend was assumed that envisaged a reduced run-off in the south and an increased run-off in the north. The changes to the mean annual run-off levels over all rivers lay between -1.7% and +15%. The changes to the extreme annual run-off levels lay between -30% and +40%.
The climate effect examined was flooding in low-lying areas of the Baltic Sea region through the increase in sea-level or river run-off.
The vulnerability analyses of the project not only include an assessment of the climate effects, but also an evaluation of the socio-economic and ecological adaptive capacity. The level of vulnerability is thus a result of the strength of the climate change impact in each case, plus the adaptive capacity or ability to deal with the climate effects. The results show that the vulnerability of the case study areas varies with the exposure and adaptive capacity, in each case.
The focus of the project lay in assessing the climate effects, and not in the development of adaptation measures. However, the project results will be summarized in a decision support system for the assessment of climate effects. The decision support system addresses local and regional planning authorities in the case study areas and the cooperation agencies for the spatial development of the entire Baltic Sea region. From this, adaptation strategies can be derived in a next step, e.g., for spatial planning.
European Union, European Regional Development Fund (ERDF), Baltic Sea Region (BSR), Interreg III B, neighbourhood programme
Geological Survey of Finland (GTK)
Centre for Urban and Regional Studies (CURS/YTK, Finland);
Swedish Meteorological and Hydrological Survey (SMHI, Sweden);
University of Greifswald (Germany);
Regional Council of Itä-Uusimaa (Finland);
Regional Planning Office Mecklenburg-Western Pomerania;
City Government of Pärnu;
Geological Survey of Poland;
City Council of Gdansk; Helsinki City;
Stockholm City and Region;
Uusimaa Regional Council;
Coastal Defense Division - Ministry of the Interior (Schleswig-Holstein);
Office of Regional Planning and Regional Transportation Stockholm County;
Geological Survey of Estonia;
Geological Survey of Finland
Betonimiehenkuja 4
FI-02151 Espoo
Finland