Myth ledger: 'NASA's satellite software discarded the ozone hole as an instrument error'

The circulating claim. NASA's TOMS instrument had been recording the collapsing Antarctic ozone for years, but its processing software was "programmed to omit data that deviated greatly from expected measurements" — so the discovery sat, unnoticed, in NASA's own dataset until the ground-based BAS paper (claim-antarctic-ozone-hole-first-reported-from-ground-dobson-readings-1985) forced attention onto it. The tidy moral: an automated threshold silently deleted a global environmental discovery.

What secondary reconstruction complicates. RealClimate's reconstruction of the internal NASA record pushes back on both halves:

• The threshold was a calibration boundary, not a "delete anomalies" rule. The quality-control flag triggered below 180 Dobson Units — a legitimate limit of the instrument's calibrated range — which flagged readings as suspect rather than silently discarding a discovery.
• NASA had, in fact, noticed. Per the reconstruction, the Ozone Processing Team had begun investigating the anomalous readings by August 1984 and concluded they were real, not instrumental, by December 1984 — months before Farman's paper appeared. RealClimate's summary: "it wasn't true that no-one at NASA had noticed." The real bottleneck was internal communication and publication timing, not algorithmic blindness.

[unverified-quant — needs primary] The specific August 1984 / December 1984 internal-timeline dates rest on RealClimate's secondary reconstruction (Tier 2), not on a primary NASA memo or the Team's own contemporaneous record. Because the surprising, load-bearing element of this correction is when NASA privately knew, those dates need a Tier 1 source before this note can leave seedling. Routed: question-verify-nasa-ozone-processing-team-1984-investigation-dates.

Cross-domain bridge. Correcting a tidy "the automated system almost erased a true discovery" story is the same debunking move the vault runs repeatedly on AI-history origin legends — myth-werbos-invented-backpropagation, myth-linnainmaa-uncited-before-2010s, myth-amari-first-sgd-mlp — where folk history compresses a messier record into a single clean narrative. Here the move lands, for the first time in this vault, on a non-AI domain. The structurally identical astronomy near-miss: claim-bell-burnell-1967-pulsar-scruff-first-dismissed-as-interference.