Sensitivity analysis of climate change impacts on dune erosion: case study for the Dutch Holland coast

Abstract

Climate change could have large implications for the management of dunefringed coasts. Sea level rise and changes in storm wave and surge characteristics could lead to enhanced dune erosion and hence a decrease in safety levels. Here, we use the processbased model XBeach to quantify the impact of sea level rise and changing hydrodynamic boundary conditions on the magnitude of future dune erosion at two locations along the Dutch coast. We find a linear relation between sea level rise and dune erosion volume, the exact linear relation being dependent on the local hydrodynamical boundary conditions. The process driving higher erosion appears to be sea level rise, allowing waves to attack the dune at a higher level. Additional simulations illustrate that a change in the offshore wave angle, potentially produced by changes in storm tracks, could influence the erosion volume with the same order of magnitude as sea level rise. Finally, simulations with different mitigation options (i.e., sand nourishments) illustrate the strong effect of the location of the added sand to the reduction in the dune erosion volume.

Impact of asymmetric uncertainties in ice sheet dynamics on regional sea level projections

“…These types of studies are executed in order to analyze events that are infrequent but expected to have a large impact on economy and society (Jonkman et al, 2011). Including highend SLC projections is therefore the logical next step in coastal safety analysis, since coastal decision-making also needs information on the upper boundary of possible future sea level when assessing future extreme events (De Winter and Ruessink, 2017). This requires two aspects: the transformation from global average SLC projections to regional SLC projections and the provision of insight of the uncertainties of these regional SLC.…”

“…Local impact studies (e.g., De Winter and Ruessink, 2017) show that the amount of SLC may affect coasts and the corresponding mitigation measures significantly. This emphasizes the need for regional SLC projections, since the amount of SLC can deviate from global average values due to changes in ocean currents, thermal expansion and gravitational and rotational effects induced by land ice and terrestrial ground R. C. de Winter et al: Asymmetric regional sea level projections and surface water mass changes (Mitrovica et al, 2001).…”

Rebuttal RC2

“…These types of studies are executed in order to analyze events that are infrequent but expected to have a large impact on economy and society (Jonkman et al, 2011). Including highend SLC projections is therefore the logical next step in coastal safety analysis, since coastal decision-making also needs information on the upper boundary of possible future sea level when assessing future extreme events (De Winter and Ruessink, 2017). This requires two aspects: the transformation from global average SLC projections to regional SLC projections and the provision of insight of the uncertainties of these regional SLC.…”

“…Local impact studies (e.g., De Winter and Ruessink, 2017) show that the amount of SLC may affect coasts and the corresponding mitigation measures significantly. This emphasizes the need for regional SLC projections, since the amount of SLC can deviate from global average values due to changes in ocean currents, thermal expansion and gravitational and rotational effects induced by land ice and terrestrial ground R. C. de Winter et al: Asymmetric regional sea level projections and surface water mass changes (Mitrovica et al, 2001).…”

Proactive, Reactive, and Inactive Pathways for Scientists in a Changing World

“…It is likely that the majority of climate change impacts will have predominantly negative outcomes for society (e.g., fisheries decline (Descombes et al, 2015)). Expectations are that species invasions (Grieve et al, 2016), range shifts (Deutsch et al, 2015), extinctions (Stuart-Smith et al, 2015), coastal erosion (de Winter & Ruessink, 2017;Toimil et al, 2017), and altered system function (McDowell et al, 2016) will continue to occur in the future. These changes will affect society through alterations in the availability of food and human well-being (Blasiak et al, 2017).…”