Version 1 record

This page describes software that has been retired. It is accurate about Version 1 and is not a description of what runs now — see the current site and the archive.

C-02 Environment generator

Status: built

Code: services/env_generator/ — the four features, the background, the composition, the manifest writer and the timescale field each in their own module
Delivered by: specs/004-environment-generator
Covered by: services/env_generator/tests/ and tests/acceptance/test_at03_eddy_recovery.py, which scores a recovered eddy against the seeded parameters in the manifest
Not present: no check reconstructs a fully composed value — background plus four anomalies, plus pressure, plus sound speed — from the manifest's documented forms alone; the pieces are each reconstructed separately

Responsibility: synthetic four-dimensional fields plus a ground-truth manifest. Owns the failure mode of: unverifiable truth.

What it does

It invents an ocean. The output is a field over latitude, longitude, depth and time carrying temperature, salinity and pressure, from which sound speed is derived. Four features are seeded into it with recorded parameters: a mesoscale eddy of known centre, radius and strength; a front of known position and sharpness; a thermocline at known depth; and a moving feature of known drift velocity.

Alongside each generated field it writes a manifest recording those parameters, the seed the generator was given, and the generator's own version.

Why the manifest is the point

Without it, every later claim is unfalsifiable. "The eddy is recoverable from the observations" means nothing on its own; it means something when the recovery error is computed against the centre and radius that were seeded, and reported as a number. Two of the four acceptance tests score against this manifest.

The generator therefore owns the failure mode of unverifiable truth: if the manifest is incomplete, or drifts out of step with what was actually generated, every downstream measurement of skill is decoration.

The decorrelation timescale

The manifest also records the decorrelation timescale, which is not a constant. It is a field: authored per feature over a domain-wide background value, evaluated per location, and advecting with a feature that moves. Quiet water gets the background value; a fast-turning eddy gets its own; the planner needs an answer at every cell it scores, not only inside features.

Requirements: FR-02 to FR-05. Feature: 004.