Coastal erosion extent
| Object type | Damage Signal |
|---|---|
| SIGNAL Earth ID | DS-00723 |
| Observable type | Coastal erosion extent |
| Unit | area, fraction, or declared extent unit (Provisional unit carried from Step 2 DS-to-OT cleanup review; requires later OT curation if source-specific units diverge.) |
| Temporal structure | — |
| Monitoring backbone | — |
refers to the measurable loss or retreat of shoreline and coastal landforms caused by natural and anthropogenic processes. This phenomenon is primarily driven by factors such as sea-level rise, storm events, wave action, and surge forces, which collectively reshape coastal landscapes over time. Understanding coastal erosion extent is essential for assessing the vulnerability of coastal environments and the communities that depend on them.
The extent of coastal erosion varies widely depending on geographic location, coastal geomorphology, and the intensity of environmental drivers. It influences habitat distribution, sediment budgets, and human infrastructure along coastlines worldwide. Monitoring changes in coastal erosion extent supports scientific research, hazard assessment, and resource management.
Within the broader context of ocean physical changes, coastal erosion extent serves as an indicator of dynamic shoreline processes and environmental stressors. It integrates multiple causal factors and provides a spatially explicit measure of coastal land loss or transformation.
Geographic / System Context
[edit]Coastal erosion extent applies globally to shorelines and coastal landforms across diverse geographic settings, including sandy beaches, rocky cliffs, estuaries, and barrier islands. The phenomenon is not limited to a specific region or coastline but is influenced by local to regional environmental conditions such as tidal regimes, sediment supply, and coastal geomorphology. Coastal zones where sea-level rise and storm activity intersect with human development often experience pronounced erosion impacts. These areas include temperate, tropical, and polar coastlines, each exhibiting distinct erosion patterns and rates.
Monitoring and Measurement
[edit]Scientists monitor coastal erosion extent using a combination of remote sensing technologies, field surveys, and historical shoreline data. Methods include aerial and satellite imagery analysis, Light Detection and Ranging (LiDAR) surveys, Global Navigation Satellite System (GNSS) measurements, and photogrammetry. Institutions such as the Woods Hole Coastal and Marine Science Center at USGS, the Urban Coast Institute at Monmouth University, and the Baruch Institute for Marine and Coastal Sciences at the University of South Carolina contribute to data collection and research. Monitoring efforts often integrate temporal datasets to quantify shoreline changes and erosion rates over time. Coastal monitoring programs also utilize wave and storm surge measurements to correlate physical forcing with observed erosion.
Within the SIGNAL system, this phenomenon is treated as a defined environmental signal whose boundaries and measurement conventions are described below.
Signal Definition
[edit]
Coastal erosion extent is defined as the spatial measure of shoreline and coastal landform loss or retreat attributable to erosional processes driven by sea-level rise, storm events, wave action, and surge forcing. It is quantified in units of area, fraction of coastline affected, or declared extent units suitable for spatial aggregation. This signal captures the canonical state of coastal erosion as an environmental physical change impacting ocean-adjacent landforms.
Boundary Conditions
[edit]Boundary inclusions encompass all measurable retreat or loss of shoreline and coastal landforms caused by physical oceanic and atmospheric forcing, including sea-level rise, storm surge, wave action, and related hydrodynamic processes. The signal includes both gradual erosional processes and episodic events that result in land loss. Boundary exclusions are areas where apparent shoreline changes are due to non-erosional factors such as sediment deposition, anthropogenic land reclamation, or construction unrelated to natural erosional processes. Inland geomorphic changes beyond the immediate coastal zone and subsidence unrelated to oceanic forcing are also excluded.
Aggregation Semantics
[edit]Geographic aggregation of coastal erosion extent involves integrating spatial measurements across defined coastal segments or regions to assess cumulative erosion impacts. Temporal aggregation may include averaging or summing erosion extents over specified time intervals, such as seasonal, annual, or multi-year periods, to capture trends and episodic events. Cross-signal aggregation considers relationships with related environmental signals such as coastal storm surge height, global mean sea level, and sediment transport flux to contextualize erosion dynamics within broader coastal system changes. Aggregation semantics support multi-scale analysis and synthesis of coastal erosion data for environmental assessment.
Observational Status
[edit]Monitoring of coastal erosion extent is ongoing with contributions from multiple research institutions and coastal observatories. Data availability varies regionally, with some areas benefiting from high-resolution temporal and spatial datasets, while others rely on periodic surveys or remote sensing snapshots. Future SIGNAL releases aim to incorporate standardized temporal structures, enhanced monitoring backbones, and refined causal attributions to improve the resolution and usability of coastal erosion extent data. Integration with complementary environmental signals will enhance understanding of erosion drivers and impacts.
Related Signals
[edit]- Biodiversity intactness index
- Coastal storm surge height
- Extreme wind intensity
- Global mean sea level
- Mangrove area extent
- Marine construction disturbance from offshore energy infrastructure
- Sediment flux to rivers/coasts
- Sediment transport flux
Key People
[edit]- Urban Coast Institute at Monmouth University
- Woods Hole Coastal and Marine Science Center at USGS
- Baruch Institute for Marine and Coastal Sciences at University of South Carolina
- Cooperative Institute for Marine, Earth and Atmospheric Systems (CIMEAS)
- Arctic Coastal Geoscience Lab at University of Alaska Fairbanks
Key Associated People
[edit]- A.H. Sallenger — U.S. Geological Survey [Source author; High]
- E.A. Pendleton — U.S. Geological Survey [Source author; High]
Inclusion reflects material contribution to the scientific understanding of this damage signal; it does not imply review, endorsement, or affiliation with SIGNAL Earth.
Sources
[edit]- Coastal Vulnerability Assessment of Olympic National Park to Sea-Level Rise — U.S. Geological Survey Open-File Report 2004-1021, 2004. DOI: 10.3133/ofr20041021. [Report; Assessment; High]
- National Assessment of Hurricane-Induced Coastal Erosion Hazards: Mid-Atlantic Coast — U.S. Geological Survey Open-File Report 2013-1084, 2013. DOI: 10.3133/ofr20131084. [Report; Assessment; High]
- Global Sandwatch Dataset – Participatory Monitoring of Beaches and Coastal Environments — UNESCO IHP Water Information Network System (IHP-WINS), 2025. [Dataset; Dataset; Medium]