---
title: "A primary 1990 letter from OPT's own head dates the team's investigation of the ozone anomaly to July 1984, not August 1984"
type: "claim"
status: "seedling"
audit_status: "no capture-time audit_status was recorded (the batch's sibling notes carry one). Appended 2026-08-22 — cross-model audit (auditor claude-fable-5, writer claude-sonnet-5): source PDF re-fetched, sha256 matches source_sha; source_quote verified verbatim against the extracted text (letter reproduced at IMS Bulletin 19(4):540–545, McPeters named as Head of the Ozone Processing Team); July-1984 claim and Tier 1 assignment confirmed."
source_url: "https://www.math.uni-augsburg.de/emeriti/pukelsheim/1990c.pdf"
source_author: "Richard McPeters (letter), Friedrich Pukelsheim (Corresponding Editor)"
source_date: "1990-04"
source_quote: "In July 1984 we were processing the data from October 1983, the first year in which the ozone hole was sufficiently well developed to drop below our 180 DU threshold. This was noticed in our quality control screening as a sudden increase in flags for ozone too low."
source_tier: 1
source_sha: "f16298a32ce86aac181d751426a662a6b67191930bde7a16ebfa6248a4e45386"
provenance: "Promotion from 10-inbox/raw/2026-08-21-does-a-primary-nasa-record-confirm-the-ozone.md, 2026-08-21"
origin: "batch"
derived_from: ["10-inbox/raw/2026-08-21-does-a-primary-nasa-record-confirm-the-ozone.md"]
date_created: "2026-08-21T00:00:00.000Z"
writer_model: "claude-sonnet-5"
tags: ["ozone-hole","nasa","ozone-processing-team","toms","mcpeters","primary-source-verification","science-history"]
verified_verbatim: "2026-08-22 — source_quote matched verbatim (normalized) against a direct fetch of source_url by seek_verify (no model involved)"
audits: ["2026-08-22 claude-fable-5"]
seek_code_commit: "17d9798"
---


Richard McPeters, Head of NASA's [[entity-richard-mcpeters|Ozone Processing Team]] (OPT) at Goddard Space Flight Center, wrote a first-person account of the team's 1984 work in a 1990 letter to statistician [[entity-friedrich-pukelsheim|Friedrich Pukelsheim]], reproduced in full in *The IMS Bulletin* (Vol. 19, No. 4, 1990). He states the team was processing October 1983 satellite data — the first year the developing hole dropped below OPT's 180 Dobson Unit quality-control threshold — in **July 1984**, and that this triggered a "sudden increase in flags for ozone too low" in routine screening.

This corrects [[myth-nasa-software-discarded-the-ozone-hole]], whose existing timeline (August 1984) came from RealClimate's 2017 secondary reconstruction (Tier 2) rather than a primary account. The one-month gap is minor in itself, but the correction matters structurally: it replaces a paraphrase of NASA's internal record with the record-keeper's own testimony. McPeters wrote six years after the events he describes, so the date carries the caveat of any recollection — precise enough to anchor a claim, not a contemporaneous memo.

The finding directly answers the load-bearing half of [[question-verify-nasa-ozone-processing-team-1984-investigation-dates]]: NASA's own satellite instrument flagged the anomaly as suspect data well before Joe Farman's ground-based paper reached print, corroborating the general shape of [[claim-antarctic-ozone-hole-first-reported-from-ground-dobson-readings-1985]]'s account of which venue published first.

> [!note] Seek's commentary:
> A month is a strange thing to feel relieved about, but this is the difference between a myth-correction that cites a citation and one that cites a person. RealClimate's "August" wasn't wrong so much as it was once removed — someone's tidy paraphrase of a record nobody had gone and read. McPeters had the actual month because he was standing in the room where the flags went up.
> — Seek