Can beaches survive climate change?

Abstract

Anthropogenic climate change is driving sea level rise, leading to numerous impacts on the coastal zone, such as increased coastal flooding, beach erosion, cliff failure, saltwater intrusion in aquifers, and groundwater inundation. Many beaches around the world are currently experiencing chronic erosion as a result of gradual, present‐day rates of sea level rise (about 3 mm/year) and human‐driven restrictions in sand supply (e.g., harbor dredging and river damming). Accelerated sea level rise threatens to worsen coastal erosion and challenge the very existence of natural beaches throughout the world. Understanding and predicting the rates of sea level rise and coastal erosion depends on integrating data on natural systems with computer simulations. Although many computer modeling approaches are available to simulate shoreline change, few are capable of making reliable long‐term predictions needed for full adaption or to enhance resilience. Recent advancements have allowed convincing decadal to centennial‐scale predictions of shoreline evolution. For example, along 500 km of the Southern California coast, a new model featuring data assimilation predicts that up to 67% of beaches may completely erode by 2100 without large‐scale human interventions. In spite of recent advancements, coastal evolution models must continue to improve in their theoretical framework, quantification of accuracy and uncertainty, computational efficiency, predictive capability, and integration with observed data, in order to meet the scientific and engineering challenges produced by a changing climate.

Pathways to resilience: adapting to sea level rise in Los Angeles

“…In a recent study, Vitousek et al ., () simulates that with limited human intervention, 31–67% of Southern California beaches could completely erode by the year 2100, assuming sea level rises of 1 m (3.3 ft) and 2 m (6.5 ft), respectively. In an older study, Heberger et al .…”

“…Beaches are already threatened by coastal flooding and coastal erosion (Vitousek et al, 2017). Although coastal erosion affecting beaches is cyclical (erosion during winter storms and accretion during summer), beach erosion has become increasingly more severe as sea levels rise, threatening beach facilities and thus tourism (Flick, 2013) as well as beach ecosystems (CEVA, 2017).…”

Time‐Varying Emulator for Short and Long‐Term Analysis of Coastal Flood Hazard Potential

“…The observed sea level rise (SLR) has already been linked to increases in nuisance flooding (Ray & Foster, ; Sweet & Park, ), beach erosion or shoreline retreat (Albert et al, ; Wahl & Plant, ), and coastal habitat loss (Jankowski et al, ). A global SLR acceleration rate of 0.084 mm/year 2 has been observed in altimeter data since 1993 (Nerem et al, ), and higher rates are expected in the 21st century (Sweet et al, ), resulting in numerous studies focused on how the frequency of coastal hazards will increase into the future (Vitousek et al, ; Vousdoukas et al, ) as well as associated increases in vulnerable coastal populations (Neumann et al, ).…”

A Climate Index Optimized for Longshore Sediment Transport Reveals Interannual and Multidecadal Littoral Cell Rotations

“…Beaches around the world are currently experiencing chronic erosion, which is only expected to worsen due to global climate change (e.g., Vitousek, Barnard, Limber, ). The nearshore science community has recognized that predicting coastal vulnerability into the 21st century requires the development of quantitative methodologies to assess long‐term coastal evolution in nonstationary climates (Elko et al, ).…”