Majuro atoll-evidence canary inputs

Stage 15 ledger · canary report · source manifest

This directory separates authoritative public source packages from compact, checked exploration derivatives used by the Stage 15 Majuro evidence canary. It does not define a standard or optional generation pass.

Storage boundary

assets.static/atoll-evidence/.raw/ contains the original USGS archives, catalog responses, and metadata. The complete directory is explicitly ignored by Git. In particular, the 2,355,022,535-byte 1 m TBDEM archive and the 80,927,783-byte inundation archive are local source evidence, not repository or release payloads.

prepared/ contains three checked approximately 10 m GeoTIFF derivatives:

Derivative	Source grid	Preparation
`majuro-tbdem-observation-10m.tif`	USGS 1 m Float32 topobathymetric DEM	Average resampling; 4,623 × 2,381; source CRS, LMSL heights, and NoData retained
`majuro-marine-inundation-30in-deterministic-10m.tif`	USGS 1 m Byte 30-inch static-water scenario	Nearest-neighbor resampling; 3,973 × 1,272
`majuro-marine-inundation-30in-probability-10m.tif`	USGS 1 m Float32 probability field	Average resampling; 3,973 × 1,272; values remain zero through one

These derivatives are review and rendering conveniences. They are not a replacement for the authoritative 1 m packages and may not lend their nominal resolution to freshwater, infrastructure, shoreline, reef, or ocean-heat claims.

context/water-myriahedral-pacific-700x394.png is a fixed 8-bit sRGB derivative of the Stage 14 authoritative Myriahedral Pacific water raster. It is only a planetary locator. Keeping this 219,197-byte input checked makes the canary generator offline and prevents a clean clone from transitively fetching Natural Earth merely to rebuild the inset.

Explicit workflow

Fetching, preparation, generation, and checking are separate operations:

# Network operation; writes only to ignored .raw/.
make fetch-atoll-evidence-data

# Local source conversion; requires the two raw archives.
make prepare-atoll-evidence-data

# Offline fixture and PNG generation from checked compact inputs.
make build-atoll-evidence-fixtures
make generate-atoll-evidence-canary

# Rebuild the exploration PNG and check hashes, dimensions, schemas,
# ignored-source boundaries, and face-qualified forward/reverse traces.
make check-atoll-evidence-canary

No target above is included by make all, ordinary make check, a GitHub release, or the human-invoked UCB AAO/S3 path. prepare-atoll-evidence-data does not fetch, and generation never reads or downloads the raw archives.

Evidence and uncertainty

The TBDEM is a 1944–2016 multi-source composite in ITRF2008 / UTM zone 59N with local mean-sea-level heights. Published validation reports land RMSE 0.197 m, Landsat-derived bathymetry RMSE 1.066 m, and WorldView-3-derived bathymetry RMSE 1.112 m. These are source-class values, not one per-cell certainty field.
The selected inundation layer is a modeled 0.762 m, or 30-inch, water level above Mean Higher High Water. It is not an observed flood. The source gives cumulative vertical RMSE 0.192 m and a separate probability surface from 750 Monte Carlo DEM realizations.
Freshwater spatial evidence, authoritative infrastructure, a current independent shoreline, reviewed benthic reef geometry, and local/regional governance review remain unavailable or incomplete and are not rendered.

The manifest is the machine-readable authority for package hashes, preparation history, layer status, output identity, and claim boundaries.