Map Layers
Composite Risk Index
HIGH
MED
LOW
Click a zone on the map to open its full report.
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Live Surface Temp
Woods Hole gauge
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Sea Level
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

Observed Forecast (ML, 90% band) Baseline / reference
Temperature & Sea Level
Sea Surface Temperature ML
Cape waters show a steady long-term warming trend, consistent with the broader Gulf of Maine.
Sea Level Rise ML
Sea level keeps climbing — the Northeast Atlantic is a documented hotspot of accelerated rise.
Chemistry & Conditions
Ocean pH
Steadily acidifying as the ocean absorbs CO₂ — a long-term stress on shellfish and larvae.
Salinity ML
Gradually freshening over two decades — a signal of shifting precipitation and ocean mixing.

Ecosystem Health

Habitat status compiled from published research, agency monitoring, and satellite vegetation analysis

Good Fair Concern
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 that delivers Sentinel-2 imagery to two pipelines: a CoastSat U-Net for ML-derived shoreline detection (primary) and an NDWI threshold composite (fallback). Source of all satellite erosion rates.
earthengine.google.com
ESA Sentinel-2
10-meter multispectral satellite imagery feeding both the CoastSat U-Net classifier and the NDWI fallback. Sept-Oct seasonal window each year, 2018-2024 reference period.
Copernicus Sentinel-2
CoastSat U-Net
Open-source deep-learning model (UNSW Water Research Lab) trained on labeled satellite imagery to classify water/land per pixel and trace sub-pixel shoreline polylines. Primary source of ML-flagged erosion rates.
github.com/kvos/CoastSat
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

The dashboard combines three independent data streams: satellite imagery (for shoreline change), NOAA tide-gauge readings (for ocean conditions), and ground-survey rates (for calibration). Two machine-learning layers sit on top — one for satellite shoreline detection, one for forecasting ocean trends. Everything else is plain arithmetic, transparently scored.

1 · Satellite shoreline detection

ESA Sentinel-2 imagery (10 m resolution) is pulled through Google Earth Engine for each of the 19 zones, restricted to a September–October window each year so beaches are compared in their late-summer profile (after rebuilding, before nor'easters). This eliminates seasonal noise from the change signal.

Primary method — CoastSat U-Net: a deep-learning model trained on labeled satellite imagery that classifies water/land per pixel and extracts a sub-pixel shoreline polyline for each scene. Robust to wet sand, cliff shadows, seaweed, and breaking waves where simple thresholds fail.

Fallback — NDWI threshold: a spectral index on the Green and Near-Infrared bands. Faster, simpler, less accurate on edge cases. Used where ML output isn't yet available.

Per-year shoreline positions feed a linear regression to produce 2-, 3-, 5-, and 7-year erosion rates. For tidal-flat zones (Barnstable, Dennis & Brewster) where a stable shoreline length can't be defined, rates are reported in ac/yr instead of ft/yr.

CoastSat U-Net (primary) NDWI = (Green − NIR) / (Green + NIR) (fallback) 10 m resolution Sept–Oct window

2 · Ocean conditions

Sea surface temperature, sea level, and salinity charts are built from NOAA CO-OPS Station 8447930 (Woods Hole, MA) — the closest continuously-operating tide gauge to the region. SST and SLR are pulled as real annual averages back to 1993 (sea level) and 2005 (temperature). Salinity uses dashboard-maintained historical values because no live API source exists for that station.

NOAA CO-OPS · Woods Hole 8447930 Annual averages, real measurements

3 · Probabilistic forecasts (Gaussian Process)

The dashed "ML Proj." line on every ocean chart comes from Gaussian Process regression — a real machine-learning model fit to the historical NOAA series. The shaded purple band shows the 90% confidence envelope — the model's range of plausible values around the projected trend, widening into the future as uncertainty grows. Charts forecasted this way (Sea Surface Temperature, Sea Level Rise, Salinity) show an ML badge next to their title.

Outlier years (e.g. partial-year readings or sensor anomalies) are automatically flagged via a residual-based detector and excluded from the fit, so a bad reading doesn't skew the projection.

GP kernel: ConstantKernel × RBF + WhiteNoise 90% confidence band Automatic outlier exclusion

4 · Composite Risk Index

Each zone receives a composite score (0–10) built from three independent dimensions — the same Hazard × Exposure × Vulnerability framework FEMA, IPCC, and most coastal-risk literature use. The three dimensions are computed separately and then averaged into the composite.

Hazard — how dangerous is the physical process here? Combines the 7-year erosion rate (prefers CoastSat ML rate when available, falls back to USGS/MCZM survey), the trend direction (accelerating / steady / decelerating), and the zone's ocean exposure (open Atlantic vs. sheltered bay).

Exposure — what's in harm's way? Combines building density along the coast, habitat coverage within the zone, and protected-land presence.

Vulnerability — how easily does damage propagate? Combines beach type (cliffs and marshes don't recover; sandy beaches rebuild; barrier islands roll back), shoreline armoring, and current habitat stress.

Thresholds are relative, not absolute. Each zone is ranked against the other 18 in the region — the bottom third are colored Low, the middle third Medium, the top third High. This means "Low" here means lower-risk *relative to other Cape & Islands zones*, not absolutely safe. Zone polygon colors on the map reflect this ranking.

The framework helps surface zones where multiple factors overlap. A zone with high erosion but nothing built behind it scores differently from a zone with moderate erosion and dense development.

Hazard × Exposure × Vulnerability Quantile thresholds (33% / 67%)

Citing This Dashboard

Cape and Islands Conservation Dashboard (2026). Coastal erosion and habitat monitoring for Martha's Vineyard, Nantucket, and Cape Cod. Satellite analysis: ESA Sentinel-2 + CoastSat U-Net via Google Earth Engine. Ocean data: NOAA CO-OPS Station 8447930 (Woods Hole, MA). Forecasts: Gaussian Process regression. Survey rates: USGS National Shoreline Change Database. Coastal management data: MA Coastal Zone Management.