Wildfire smoke
2020-09-06 2-area wildfire-smoke episode
Named source Cameron Peak Fire 208,913 acres , CO · IRWIN 2020-COARF-000636
Daily PM2.5 peaked at 49.7 µg/m³ near Denver across 2 covered metros home to 3.8 million people.
Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 1.7 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 6.5 million cigarettes. An awareness illustration of outdoor exposure at 22 µg/m³ per cigarette (Berkeley Earth), counting only the event's ranked days; not a medical dose.
Episode peak
-- cigarettes
The smoke map's scale, replayed over this event: the surface interpolates between covered metros' daily records, framed to the affected region. Hover for a reading, click a metro to pin it to the card. Days a monitor did not report draw nothing.
What happened, in the record
Supplied qualified evidence supports wildfire-smoke as the root cause. The grouping includes only events linked by explicit shared episode evidence; otherwise this remains a single-event episode.
Sequence: Denver (Sep 6) → Colorado Springs (Sep 7)
Affected metros
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Denver-Aurora-Lakewood, CO | 49.7 µg/m³ | 2.3 | Sep 6, 2020 | #17 of its top days |
| Colorado Springs, CO | 27.7 µg/m³ | 1.3 | Sep 7, 2020 | #17 of its top days |
"Cigarettes, whole event" totals a metro's ranked event days at 22 µg/m³ per cigarette: what a person outdoors there breathed across the event, as the illustration. "All-time standing" is where this episode's days sit in each metro's ranked record (worst-area measure, since 1999). Full local context is on each metro's Air Records page.
The evidence
Agency and publisher pages 2
- Smoky Sunday: Cameron Peak Fire affects air quality across the Front Range Contemporaneous reporting states that Cameron Peak Fire smoke affected Front Range air quality; it reports a state particulate action day and degraded Denver conditions.
- Cameron Peak Fire Creates Huge Smoke Plume, Unhealthy Air Conditions Coverage reports the Cameron Peak Fire smoke plume being carried into the Denver metro area from September 6-7.
What remains uncertain
- The supplied evidence resolves cause but does not establish identity with another candidate episode.
Status and provenance
Research preview: this record carries research-only status and its boundaries, cause, and name may change as evidence review completes. Grouping policy common_sense_root_cause_grouping.v2. The cause label reflects the assembled evidence above, not an IAQng detection formula.