Wildfire smoke
June 25–27, 2003 southeastern U.S. wildfire-smoke episode
Daily PM2.5 peaked at 46.9 µg/m³ near Chattanooga across 5 covered metros home to 6.0 million people.
Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 2.9 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 17 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
Qualified frozen evidence supports wildfire smoke as the broad root cause and supports grouping the contemporaneous affected events into one time-bounded episode. Qualified frozen evidence supports wildfire smoke as the broad root cause and supports grouping the contemporaneous affected events into one time-bounded episode.
Sequence: Charlotte (Jun 25) → Chattanooga (Jun 26) → Winston (Jun 26) → Greensboro (Jun 26) → Greenville (Jun 26)
Affected metros
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Chattanooga, TN-GA | 46.9 µg/m³ | 2.1 | Jun 26, 2003 | #15 of its top days |
| Winston-Salem, NC | 45.5 µg/m³ | 2.1 | Jun 26, 2003 | #13 of its top days |
| Charlotte-Concord-Gastonia, NC-SC | 41.7 µg/m³ | 5.6 | Jun 26, 2003 | #18 of its top days |
| Greensboro-High Point, NC | 41.3 µg/m³ | 3.7 | Jun 26, 2003 | #16 of its top days |
| Greenville-Anderson-Mauldin, SC | 40.1 µg/m³ | 1.8 | Jun 26, 2003 | #18 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
EPA AQS monitor qualifier 4
- AQS PM2.5 qualifier E — Forest Fire. EPA AQS carries an agency-submitted request-exclusion qualifier (E, Forest Fire.) on 1 PM2.5 sample in the candidate CBSA on 2003-06-25, identifying wildfire smoke as affecting the sample. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.
- AQS PM2.5 qualifier E — Forest Fire. EPA AQS carries an agency-submitted request-exclusion qualifier (E, Forest Fire.) on 1 PM2.5 sample in the candidate CBSA on 2003-06-27, identifying wildfire smoke as affecting the sample. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.
- AQS PM2.5 qualifier E — Forest Fire. EPA AQS carries an agency-submitted request-exclusion qualifier (E, Forest Fire.) on 3 PM2.5 samples in the candidate CBSA on 2003-06-26, identifying wildfire smoke as affecting the samples. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.
- AQS PM2.5 qualifier E — Forest Fire. EPA AQS carries an agency-submitted request-exclusion qualifier (E, Forest Fire.) on 5 PM2.5 samples in the candidate CBSA on 2003-06-26, identifying wildfire smoke as affecting the samples. A request-exclusion qualifier is an official submitting-agency causal claim, but this endpoint does not establish EPA concurrence.
What remains uncertain
- AQS qualifiers are submitting-agency causal flags and do not by themselves establish EPA concurrence.
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.