Map Layers
ML Zone Risk (click a zone to explore)
High
Medium
Low
——
Surface Temp LIVE
Woods Hole gauge
——
Sea Level NOAA
above 1993 base
1.8 ft/yr
Avg Erosion
accelerating
96,800 ac
Protected Coast
across Cape & Islands
Click any highlighted area to explore its data

Ocean & Climate Data

Live and historical data covering Cape Cod, Martha's Vineyard, Nantucket, and the Elizabeth Islands

Temperature & Sea Level
Sea Surface Temperature
Sea Level Rise
Chemistry & Conditions
Ocean pH
Salinity

Ecosystem Health

Habitat status updated quarterly from aerial surveys, satellite NDVI, and field monitoring

Region-Wide Overview
Eelgrass / Seagrass
Concern
Coverage down 34% since 2000 across the region. Nitrogen loading from septic systems is the primary driver. Waquoit Bay and Buzzards Bay most impacted. Restoration efforts underway but recovery is slow.
Salt Marsh
Fair
Sea level rise is outpacing vertical accretion in many areas. Wellfleet Bay and Barnstable Harbor marshes showing signs of drowning. Some marshes stable where sediment supply is adequate.
Shorebird Nesting
Good
Piping Plover numbers up 18% over 5 years on MV. Tern colonies stable across all three regions. Predator management and beach closures proving effective.
Shellfish Habitat
Fair
Oyster and quahog populations stable. Ocean acidification threatens larval survival long-term. Active aquaculture on Brewster Flats and Wellfleet Harbor. Scallop populations declining in nitrogen-impacted bays.
Coastal Wetlands
Concern
Over 400 acres lost in the past decade. Inland migration blocked by roads and development. Thin-layer sediment deposition being piloted at several sites to boost marsh elevation.
Dune Vegetation
Fair
Beach grass plantings showing success at Lobsterville and MV south shore. Storm overwash and vehicle traffic remain primary threats. Cape Cod National Seashore dune systems declining.
Lobster Population
Concern
Southern New England populations in long-term decline as warming pushes range northward. Cape Cod Bay catch down significantly. Major economic impact for the fishing fleet.
Fish Habitat
Good
Striped bass and bluefish populations stable. Range shifts northward consistent with warming. Black sea bass expanding into the region. Herring runs recovering with fish passage improvements.

Erosion & Risk — All Zones

All 19 monitored zones ranked by erosion severity · click any row to open its detail panel

Sort by:
# Zone Region Survey Rate Sat Rate (7yr) Risk

Survey rates: USGS CoSMO · Satellite rates: ESA Sentinel-2 via GEE

Data Sources

Federal, state, and satellite data powering this dashboard

Federal & State Data
NOAA CO-OPS
Live tide gauge data from Station 8447930 (Woods Hole). Provides the dashboard's real-time sea surface temperature, sea level anomaly, and salinity series (2005–present) via batched monthly API calls.
Woods Hole 8447930 · Physical Oceanography
Google Earth Engine
Cloud processing platform used to run Sentinel-2 NDWI analysis across all 19 coastal zones. Averaging composite method with refined polygon boundaries for ocean-facing shoreline calibration. Source of all satellite erosion rates.
earthengine.google.com
ESA Sentinel-2
10-meter multispectral satellite imagery (Green + NIR bands) used for NDWI-based waterline extraction and land-loss detection across 2-, 5-, and 7-year time windows.
Copernicus Sentinel-2
USGS CoSMoS / DSAS
National Shoreline Change Database. Provides historical survey-based erosion rates (ft/yr) used as ground-truth calibration for each zone's satellite-derived rates.
USGS Coastal Hazards Portal
MassGIS / OLIVER
Protected land parcels, conservation restrictions, and habitat classifications for Cape Cod, Martha's Vineyard, and Nantucket. Used in the Ecosystem tab and zone detail panels.
MassGIS
MA Coastal Zone Management
StormSmart Coasts program, shoreline change technical reports, and coastal erosion policy data. Informs risk classification methodology and zone-level threat assessments.
mass.gov/czm
NASA Earthdata
MODIS and Sentinel-2 satellite imagery for SST, NDVI vegetation index, and coastline change detection.
earthdata.nasa.gov
NOAA NDBC Buoys
Real-time buoy data for wave height, water temperature, wind, and ocean conditions in Buzzards Bay and Vineyard Sound.
ndbc.noaa.gov

Data Methodology

How satellite rates, erosion figures, and risk classifications are calculated

Satellite Erosion Analysis (Sentinel-2)

Coastal land-change detection uses ESA Sentinel-2 multispectral imagery processed through Google Earth Engine. For each zone, a waterline is extracted using the Normalized Difference Water Index (NDWI) — a spectral index that separates water from land using the Green and Near-Infrared bands. Land loss is calculated as the area (m²) that transitioned from land to water between the start and end composite of each time window.

Three windows are computed per zone: 2-year (recent trend), 5-year (medium-term), and 7-year (primary reference, 2018–2025). The 7-year rate is used for all ft/yr calculations shown in zone panels.

Converting area loss to linear retreat requires dividing by each zone's calibrated shoreline length, tuned to match published USGS survey rates. Tidal-flat zones (Barnstable, Dennis & Brewster) are reported as ac/yr where a reliable shoreline length cannot be defined.

NDWI = (Green − NIR) / (Green + NIR) 10m resolution Cloud-filtered composites ft/yr = (annual m²/yr ÷ shoreline m) × 3.28084

ML Zone Risk Model

Each zone is scored 0–10 by a risk model that incorporates OLS regression analysis on historical erosion and satellite data to detect trend acceleration, combined with erosion rate, habitat stress, and threat severity. The model ranks zones so conservation effort can be prioritized where multiple threats overlap, not just where erosion is fastest.

Thresholds: ≥7 = High, 4–7 = Medium, <4 = Low. Zone colors on the map reflect this score.

Ocean data charts (SST, sea level, salinity) include OLS linear regression trend lines with 5–10 year forward projections, labeled as "ML Proj." in the legend.

Citing This Dashboard

Cape and Islands Conservation Dashboard (2025). Coastal erosion and habitat monitoring for Martha's Vineyard, Nantucket, and Cape Cod. Satellite analysis: ESA Sentinel-2 via Google Earth Engine. Live ocean data: NOAA CO-OPS Station 8447930 (Woods Hole, MA). Survey rates: USGS National Shoreline Change Database. ML risk model: weighted multi-factor scoring. Coastal management data: MA Coastal Zone Management.