Report on vulnerability of the Wadden Sea World Heritage to climate change published

Extreme heat events, temperature increase and sea level rise could be the key stressors of climate change, which will affect the Wadden Sea World Heritage site. This is the main outcome of an innovative rapid assessment, the Climate Vulnerability Index (CVI), which was applied by international experts in February 2020. The findings of the workshop have now been published in a comprehensive report by the Common Wadden Sea Secretariat (CWSS) in cooperation with the trilateral Expert Group Climate Change Adaptation (EG-Climate) and the designers of the tool, Jon Day and Dr Scott Heron of James Cook University, Australia. With the help of the CVI the workshop looked at stressors and their possible implications. For more profound evidence on the severity of their impacts, in-depth research is needed.

Each World Heritage site carries an Outstanding Universal Value (OUV), the characteristics that led to the inscription onto the World Heritage List. The Wadden Sea’s Value is, in short, that it is the largest tidal flats system in the world, where natural processes proceed largely undisturbed. It encompasses a multitude of habitats and is rich of species adapted to the demanding environmental conditions, and is considered one of the most important areas for migratory birds in the world. The CVI is a rapid assessment tool identifying the climate pressures specific to a World Heritage site’s OUV as well as its vulnerability to those pressures. It has already been applied in Shark Bay, Australia, and in the Orkney Islands, Scotland.

The February workshop was comprised of 40 participants with diverse expertise including government agencies, nature conservation, science and administration of the three Wadden Sea countries. The group ranked three key climate stressors impacting the Wadden Sea’s OUV as the most pressing ones: temperature increase, more severe extreme heat events and sea level rise. The three stressors were held against the key elements of the OUV and possible impacts of climate change were discussed for two time frames: 2050 and 2100. The workshop assessed the OUV vulnerability as overall high for both timeframes. The impact of the first two key climate stressors was considered as high for both time periods. The stressor “sea level rise” was seen as low with regard to 2050, with a less rapid rise in this period, and as high for 2100, with the sea level expected to rise more rapidly between 2050 and 2100. The scenario high vulnerability holds that a major loss or substantial alteration of the majority of the OUV attributes is foreseen if the climate changes.

“This process helped us realise that we really have to look more carefully at the potential effects of temperature increase and extreme heat events on the Wadden Sea,” says Robert Zijlstra, Chair of EG-Climate. Discussion on climate change ad­aptation strategies often focus on measures associated with sea level rise.  The known possibilities to adapt to climate change are still rather limited. “We need to intensify research on the possibilities for adaptation” Zijlstra adds. “In the workshop it was also concluded that it is important to min­imise other stressors on the ecosystem to safeguard a sound ecosystem, which we expect to be more resilient to climate change than a system under many other stressors. And the best way to protect the Wadden Sea from these threats is still to reduce our CO2 emissions and limit climate change”

The trilateral Expert Group Climate Change Adaptation will update the priorities of the 2018 adopted Climate Change Adaptation Strategy using the new findings and continue to promote the implementation of the strategy’s principles. The group will also investigate if pilot sites or pro­jects can be found to showcase the application of the strategy and stimulate a knowledge exchange of the principles of adaptation in the Wadden Sea.

A workshop to undergo the second phase of the two-phase Climate Vulnerability Index tool, the assessment of the Wadden Sea’s community vulnerability, is planned for the year 2021. This phase is based on the economic, social and cultural dependencies upon the World Heritage site and the adaptive capacity of these to cope with climate change.

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