Researchers: “Only a dam across the North Sea helps against projected sea rises”

New research suggests that only dams of nearly 600 kilometres could protect northern Europe against a sea level rice of several metres. They state that if we do not succeed in mitigation this kind of infrastructural projects are needed. Researcher Sjoerd Groeskamp, oceanographer at the Royal Netherlands Institute for Sea Research and Joakim Kjellson at GEOMAR in Kiel, Germany, recently published their study in The Bulletin of the American Meterological Society.

Building a 475 kilometres long dam between the north of Scotland and the west of Norway and another one of 160 kilometres between the west point of France and the southwest of England could act as a defence against climate change. The costs of 250-500 billion euros are merely 0.1% of the gross national product annually over 20 years, of all the countries that would be protected by such a dam. “The design of this extreme dam is mainly a warning”, states Groeskamp. “It reveals the immensity of the problem hanging over our heads. We need to stop climate change now.”

Technically feasible

“The construction of  a North-European Enclosure Dam seems to be technically feasible”, states Groeskamp. “The maximum depth of the North Sea between France and England is scarcely one hundred metres. The average depth between Scotland and Norway is 127 metres, with a maximum of 321 metres just off the coast of Norway. We are currently able to build fixed platforms in depths exceeding 500 metres, so such a dam seems feasible too.”

Freshwater lake

The researchers acknowledge that the consequences of this dam for North Sea wildlife would be considerable. Groeskamp: “The tide would disappear in a large part of the North Sea, and with it the transport of silt and nutrients. The sea would eventually even become a freshwater lake. That will drastically change the ecosystem and therefore have an impact on the fishing industry as well.”

Warning

The plans for this extreme dam are more a warning than a solution, Groeskamp states. “The costs and the consequences of such a dam are very high. However, we have calculated that the costs of doing nothing against sea level rise will be much higher. This dam makes it almost tangible what the consequences of the sea level rise will be; a sea level rise of 10 metres by the year 2500 according to the bleakest scenarios. This dam is therefore mainly a call to do something about climate change now. If we do nothing, then this extreme dam might just be the only solution.”