Climate change threatens North-west Europe´s coastal areas primarily through accelerated sea-level rise, increasing storm surges, and increasing winter rainwater discharge. Today’s coastal land management is based on the protection against floods by sea walls and groundwater regulation by drainage. Accelerating sea-level rise and changes in hydrological cycles are likely to affect coastal ecosystems and may restrict the efficiency of these
measures in the future.
COMTESS will perform an inter- and transdisciplinary investigation of four scenarios, applied to a North Sea and a Baltic Sea coastal
region in Germany:
(1) Water management: Construction of second coastal defense lines
within the hinterland instead of heightening the primary sea wall and formation of freshwater polders enclosed by the primary and secondary dike line. Primary aims of this scenario are to restrict flooding to the polder area in case of limited breaches, to increase freshwater retention for use in dry periods, to prevent subsurface salt water intrusion, and to use reeds
for green energy.
(2) Carbon sequestration: Similar to the first scenario but polders will
be extensively covered with reed fens to yield active peat formation.
(3) Trend: Dairy farming and grassland as usual. However, flood events may substantially disrupt land useand incur higher drainage costs, thus reducing the ecological and economic viability of this land management.
Each scenario implies the prioritization of certain ecosystem services (e.g. water management vs. carbon sequestration vs. food production) as well as synergies or trade-offs with other ecosystem services (e.g. biodiversity vs. green energy production). COMTESS will quantify and evaluate the performance of multiple ecosystem functions and services in each scenario in socio-economic and ecological terms. The Sustainability Economics Group will provide an economic valuation and risk analysis of the land management scenarios.