Seagrass meadows provide essential coastal protection against future marine storms

Climate change is already modifying the marine environment, and these alterations will presumably increase in the coming decades. Some of the most significant changes expected during this period include ocean warming, rise of sea level, and modifications to circulation and wind wave patterns. For instance, in the Mediterranean, ocean surface temperatures are projected to increase by 1-4 ºC by the end of the century, triggering a chain of impacts on marine ecosystems, such as species migration, significant mortality in some species, and an increase in harmful algal blooms.
Furthermore, sea levels are expected to rise, reaching values ranging from 30 cm to over 1 m by the end of the century. The consequences include the increased permanent flooding of low-lying areas, the salinization of coastal water reservoirs, and damage caused by marine storms.

In this context, despite ongoing efforts to reduce greenhouse gas emissions, it is crucial to develop realistic and effective plans for adapting to climate change. Nature-based solutions (NBS) present a particularly interesting approach to addressing climate change impacts. One NBS option suitable for reducing the impacts of climate change in coastal areas is to increase seagrass meadows through restoration interventions. The interaction of seagrasses with water flow leads to a reduction in flow energy, thereby limiting the impact of waves reaching the coast.
However, ocean warming poses a threat to seagrass meadows, as some species are particularly vulnerable to marine heatwaves. Therefore, the primary goal of the SEAFRONT project is to quantify the potential benefits of seagrass meadows in protecting the coast from future marine storms under different scenarios of global warming and seagrass evolution. SEAFRONT focuses on Spanish coastal areas, which exhibit a variety of hydrodynamical situations and seagrass coverages.
Specifically, SEAFRONT aims to 1) assess the impacts of marine storms over the last decades, evaluating the role of seagrasses; and 2) generate future scenarios of physical and economic impacts.

In this presentation, we share the results of numerical simulations focused on measuring the total water level at the shore under various scenarios. These simulations account for sea level changes, wave patterns, coastal shapes, and seagrass coverage. Additionally, we discuss the economic impacts of marine storms based on information from insurance companies.
Our initial analyses suggest that restoring seagrass meadows is a highly effective way to adapt to marine storms, countering the effects of rising sea levels. However, in areas where seagrasses already exist, losing them could lead to severe consequences, increasing the impact of marine storms.