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Coast under pressure

Crumbling cliffs, eroded beaches, flooded meadows: extreme weather events caused by climate change are putting a strain on coasts in the north. The GoCoase project is not only examining what extensive protection measures are required, but also bringing onboard the people affected by this.

© pur.pur

Which measures do people want to protect the coasts in the north of Germany -- like the cliffs seen here between Laboe and Stein? And what are they prepared to sacrifice for them?

The last few storm surges have made it clear: climate change has visibly arrived in northern Germany. It is the coastal regions in particular that are having to combat extreme weather events and their effects more and more often. Whole stretches of land remain under water for days after storms. Kilometre after kilometre, sand is eroded from beaches, cliffs crumble. For some time now, current coastal protection measures, such as dykes, groynes, beach nourishment and even the securing of cliffs, have been unable to withstand the extreme events for long. "As a result of climate change we must decide now whether and to what extent coastal protection needs to be adapted to the new conditions. At the same time, we cannot overlook nature conservation," said Professor Katrin Rehdanz, who specialises in environmental and energy economics at Kiel University.

Within the framework of the research project GoCoase, the economist is a member of a cross-university team of scientists and engineers examining what measures are necessary for coastal protection in the future, taking the Baltic Sea coastal region in Mecklenburg-Western Pomerania as its example. The three-year project is being funded by the Federal Ministry of Education and Research.

Assessment of measures

"It is actually natural for water and waves to erode sand from beaches and for cliffs to crumble. The sand will wash up again somewhere else, of course," explained Rehdanz. "But things are not that simple." The affected sections are often inhabited, farmed, or used for business or tourism. In such cases, coastal protection is necessary. "It makes sense, however, to assess what measures are useful and necessary and how much they will cost. Likewise, it makes sense to assess what people in the region and Germany as a whole are prepared to accept in order to protect the coast," said the Kiel-based economist.

The project team relies on public workshops and national surveys to find answers. "We are also working closely with the federal state (Land) of Mecklenburg-Western Pomerania, the Staatliches Amt für Landwirtschaft und Umwelt Mittleres Mecklenburg (national office for agriculture and environment in central Mecklenburg), the Verband Mecklenburger Ostseebäder (association of Baltic sea resorts in Mecklenburg), the German Farmers’ Association and other decision-makers at community to regional level," said the professor. "We want to involve as many people as possible so that we can estimate the response to potential adaptations in coastal protection to climate change. This is a first step to avoiding possible conflicts at a later date and to implementing measures that are widely accepted by the public." After all, she added, sooner or later, it will not be possible to avoid changing land use plans or abandoning an existing village, a house or a field.

Surveys to aid decision-making

Together with Dr Jürgen Meyerhoff from TU Berlin and Andrea Wunsch from the CAU, the three-member team is responsible for surveying the public. "We are interested in what significance people in Germany attach to coastal protection, what measures people prefer and to what degree – for example, the extent of dyke raising or the volume of beach nourishment – and what amount they would be willing, hypothetically, to pay for this." Around 2,100 people from all age groups, income levels and parts of Germany were surveyed online in April 2020. "The answers to this representative survey are now available."

Accordingly, the vast majority of those surveyed have been to the North Sea or Baltic Sea before (84 percent). Terms like dunes and dykes are familiar to 90 percent of those surveyed, but were explained again in the survey. The majority of respondents (80 percent) are definitely in favour of maintaining the current coastline through protection measures. However, 74 percent consider it unavoidable that, in the long term, people will have to move back from the coast as a result of the effects of climate change. As a result, 90 percent of those surveyed are against building new settlements in direct proximity to the sea.

Rehdanz is also interested in the answers relating to costs. "Around a third of those surveyed agree that only affected federal states should bear the costs of additional protection measures and not all German citizens." Other statements will be made once the survey has been assessed in full.

Results are still outstanding from the project team’s other groups. A joint publication is planned for early 2021 and will be made available not only to decision-makers in Mecklenburg-Western Pomerania to assist them with their decision-making, but also to all interested parties, as the results could help the whole of the north improve its coastal protection.

Author: Jennifer Ruske

Coastal protection of the future

The research project GoCoase (duration: 2018–2021) is examining possible strategies for adaptation to climate change for the German Baltic Sea coastal region in Mecklenburg-Western Pomerania. GoCoase is preparing and assessing adaptation strategies in close cooperation with the Staatliches Amt für Landwirtschaft und Umwelt Mittleres Mecklenburg (StALU MM) (national office for agriculture and environment in central Mecklenburg), the Verband Mecklenburgischer Ostseebäder (VMO) (association of Baltic sea resorts in Mecklenburg) and other decision-makers from community to regional level. The project partners are the Institute for Environmental, Resources and Regional Economics at Kiel University (project coordination), the Chair of Landscape Economics at Technische Universität Berlin, the Ludwig-Franzius-Institute for Waterways, Estuarine and Coastal Engineering at Leibniz University Hannover and the Coastal Union Germany (EUCC-D). The Federal Ministry of Education and Research (BMBF) is providing the project with funding of €852,000. The lead partner is the German Aerospace Center (DLR). (JR)