BIOACID II – Consortium 5: Ocean Services

Lead Proponents: Katrin Rehdanz (Kiel Institute for the World Economy and Christian-Albrechts-Universität zu Kiel CAU), Martin Quaas (CAU, Kiel)

Consortium 5 “Services of the Ocean” aims to investigate social and economic consequences of ocean acidification and to quantify them. Thus, stakeholders will be able to recognize consequences of their behaviour as well as ways to reduce climate change or adapt. Based on the scientific evidence, politics, economy and society can take joint action. They shall ensure that the oceans continue to provide food and energy, promote recreation and health, drive the tourism as an economic factor, or – and this service is considered to be economically most important – store carbon dioxide from the atmosphere and thus slow down climate change.

Model calculations show how the use of the seas impacts them and how the use options may change in the future. The focus is on the function of the ocean as a CO2 sink and fishing.

In 2008, the oceanic content of carbon increased by 2.3 gigatons. This corresponds to 8.4 gigatons of CO2. In the European Union Emissions Trading Scheme, a ton of CO2 emissions is calculated with ten euros. If the ocean absorbs only one percent less CO2 per year due to climate change, this would generate “costs” of about 0.84 billion euros. Such a development seems realistic. Reason number one is the fact that warmer water absorbs less CO2 than colder. Secondly, many plankton organisms seem to form less calcium carbonate in a more acidified water and thus fix less carbon. The natural CO2 storage device reaches its limits.

Will the future ocean provide enough food? Photo: Maike Nicolai, GEOMAR

Because it sits at the base of the marine food web, modifications in the plankton community evoked by climate change also affect fish stocks. But even some direct consequences for the extension of habitats, the growth or body functions of fish are known. At global and regional levels, biologists and economists therefore determine future changes to marine fisheries engage stakeholders in the discussion about possible options for adaptation or prevention.

More about the science of Consortium 5.