VCMP Sites - Coastal Erosion Indicators
The Coastal Erosion Indicators dataset features five statistics and a combined coastal erosion indicator value to describe the state of a beach. The statistics are calculated from data collected cross sites monitored by the Victorian Coastal Monitoring Program (VCMP) along Victoria's coastline, Sites are spatially represented as polygon data.
Coastal Erosion Indicators (Erosion Warning Indicators)
There is no one simple metric that can effectively describe the state of a beach. The approach here is to use a combination of statistics and combine them into a single 'Coastal Erosion Indicator'. This gives a multi-faceted assessment of erosion characteristics at a given site and allows for quantitative comparison across sites.
The 5 erosion statistics are:
1. Long-term shoreline change (1988 to 2021) – averaged across each site using Digital Earth Australia satellite shorelines.
2. Short-term change (last 2-years) – averaged across each site using VCMP drone surveys.
3. Ratio of shoreline eroding (last 2-years) - using VCMP drone data.
4. Ratio of backshore (dune/cliff line) eroding (last 2-years) – using VCMP drone data.
5. Max. backshore erosion (last 2-years, 3-point average alongshore) – using VCMP drone data.
The VCMP drone survey short-term outputs include shorelines for each survey, taking the ‘shoreline’ as the +1 m AHD contour for Open Coast sites, and +0.5 m AHD contour for large bay sites.
Drone survey data collection is performed as described in Pucino et al., 2021 and Ierodiaconou et al., 2022, and outlined as:
- Data processing and quality control conducted within the Propeller platform (https://vcmp.prpellr.com), with additional manual quality control checks, to achieve a horizontal-vertical uncertainty of 0.1 m or better (Pucino et al., 2021), with output products of Digital Surface Models (DSM) and orthomosaics
- Analysis is conducted using a statewide framework of 30-m spaced transects
More information about the Coastal Erosion Indicators dataset and the calculation of the erosion indicator statistics, and other datasets generated from the Victorian Coastal Monitoring Program, can be found at https://www.marineandcoasts.vic.gov.au/__data/assets/pdf_file/0023/625352/VCMP_Erosion-Indicators_April_2023.pdf