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Wildfire smoke Agency determination

2024-08-08 wildfire smoke episode affecting Boise City, ID

August 8, 2024

Named source Bogus Basin Road vegetation fire

Daily PM2.5 peaked at 64.7 µg/m³ near Boise City across 1 covered metro home to 845,877 people. 1 metro placed a top-ten day in their record.

Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 2.6 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 2.2 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.

Why we think this happened

The basis for “Wildfire smoke”

The supplied retained evidence supports wildfire smoke for this event; no supplied evidence establishes membership in a broader time-bounded episode.

Agency determination A government body issued a record naming this cause for this event: an NWS air-quality alert, a NOAA Storm Events record, or a state or local official archive.

U.S. EPA Air Quality System and the submitting air monitoring agency · Aug 8, 2024 official

AQS PM2.5 qualifier RT — Wildfire-U. S.

EPA AQS carries an agency-submitted request-exclusion qualifier (RT, Wildfire-U. S.) on 1 PM2.5 sample in the candidate CBSA on 2024-08-08, 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.

U.S. EPA Air Quality System and the submitting air monitoring agency · Aug 8, 2024 official

AQS PM2.5 qualifier IT — Wildfire-U. S.

EPA AQS carries an agency-submitted informational qualifier (IT, Wildfire-U. S.) on 119 PM2.5 samples in the candidate CBSA on 2024-08-08, identifying wildfire smoke as affecting the samples. An informational qualifier is an official submitting-agency flag, not a request for exclusion or an EPA-concurred determination.

Idaho Department of Environmental Quality via NWS · Aug 8, 2024 official

Archived Boise Air Quality Advisory, August 8, 2024

Idaho DEQ explicitly attributed degraded Boise-area air quality to wildfire smoke. IEM is the archive, not the official system of record.

See every retained source and limitation ↓

Evidence path

From source to city

A cause is more convincing when the record connects three things: something happened, the air mass moved toward the region, and local instruments responded. Here is how much of that chain is documented for this event.

Open the evidence ledger ↓
  1. 1

    Source or mechanism

    Wildfire smoke

    EPA AQS carries an agency-submitted request-exclusion qualifier (RT, Wildfire-U. S.) on 1 PM2.5 sample in the candidate CBSA on 2024-08-08, identifying wildfire smoke as affecting the sample. A request-exclusion qualifier is an official…

    View supporting source ↗
    Documented
  2. 2

    Air-mass movement

    The transport path has not been reconstructed

    The retained record does not yet show how air traveled from the proposed source to these metros. A trajectory replay or dated plume analysis belongs here.

    Research gap
  3. 3

    Local response

    64.7 µg/m³ near Boise City

    EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 2.9 cigarette-equivalents at the outdoor daily rate.

    Inspect the pollutant and weather signals ↓
    Documented

Event autopsy

What the instruments saw

Before, during, and after the episode: nearby pollutant monitors and surface-weather stations show what changed. This context tests the “Wildfire smoke” explanation; it does not assign the cause by itself.

Observed context · not attribution

Boise City, ID

Monitor comparison window 2024-08-05 to 2024-08-11 · PM2.5 target: Garden Valley

6 pollutant signals
Fine-particle pulse 64.7 µg/m³

189% above nearby days

Air movement 3.05 kt

8% lower than surrounding days

PM10 132 µg/m³

137% higher than surrounding days

Pollution fingerprint

Metro-wide median of reporting monitors
PM2.5 64.7 µg/m³

189% higher than surrounding days

Before19 µg/m³ Event64.7 µg/m³ After22.4 µg/m³
2 monitors · 24 HOUR
PM10 132 µg/m³

137% higher than surrounding days

Before47.5 µg/m³ Event132 µg/m³ After55.5 µg/m³
2 monitors · 24-HR BLK AVG
Carbon monoxide 0.591 ppm

105% higher than surrounding days

Before0.255 ppm Event0.591 ppm After0.289 ppm
1 monitor · 1 HOUR
Nitrogen dioxide 10.6 ppb

52% higher than surrounding days

Before7.01 ppb Event10.6 ppb After5.62 ppb
1 monitor · 1 HOUR
Sulfur dioxide 0.954 ppb

101% higher than surrounding days

Before0.475 ppb Event0.954 ppb After0.471 ppb
1 monitor · 1 HOUR
Ozone 0.071 ppm

46% higher than surrounding days

Before0.050 ppm Event0.071 ppm After0.043 ppm
2 monitors · 8-HR RUN AVG BEGIN HOUR

Atmospheric conditions

Nearby EPA weather observations
Humidity 33 %

6% lower than surrounding days

Pressure 922 Millibars

About the same as surrounding days

Temperature 79 °F

About the same as surrounding days

Wind 3.05 kt

8% lower than surrounding days

Source: U.S. EPA AirData daily observations and, where available, nearby ASOS/AWOS surface observations. Values are descriptive medians over the retained monitor set; missing measurements remain missing. Transport and source evidence remain separate layers because this instrument pattern does not assign a cause by itself.

Measured daily PM2.5 at EPA monitors, as cigarette-equivalents
EPA monitors sit in metro areas, so the colour clusters there. Land between and beyond them is unmeasured, not clean: this map shows where IAQng has readings, not the extent of the smoke.

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.

Views from the selected metro

Camera views near

Browse the camera map →

Select a metro on the map to see nearby cameras. Where an operator archive reaches the event, drag the divider to compare two moments, adjust either date and time, or play the available event-day frames. Camera imagery is visual context, not an air-quality measurement or proof of smoke.

Affected metros

MetroPeak PM2.5Cigarettes, whole eventPeak dayAll-time standing
Boise City, ID 64.7 µg/m³ 2.9 Aug 8, 2024 #8 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.

Public evidence library

What supports this account

Each card states what a source supports—and what it does not. Official records, research, reporting, community observations, and transparent inferences remain visibly different kinds of evidence.

EPA AQS monitor qualifier 2

  • AQS PM2.5 qualifier RT — Wildfire-U. S.

    U.S. EPA Air Quality System and the submitting air monitoring agency · Aug 8, 2024 official government

    EPA AQS carries an agency-submitted request-exclusion qualifier (RT, Wildfire-U. S.) on 1 PM2.5 sample in the candidate CBSA on 2024-08-08, 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 IT — Wildfire-U. S.

    U.S. EPA Air Quality System and the submitting air monitoring agency · Aug 8, 2024 official government

    EPA AQS carries an agency-submitted informational qualifier (IT, Wildfire-U. S.) on 119 PM2.5 samples in the candidate CBSA on 2024-08-08, identifying wildfire smoke as affecting the samples. An informational qualifier is an official submitting-agency flag, not a request for exclusion or an EPA-concurred determination.

NWS Air Quality Alert 1

  • Archived Boise Air Quality Advisory, August 8, 2024

    Idaho Department of Environmental Quality via NWS · Aug 8, 2024 official government

    Idaho DEQ explicitly attributed degraded Boise-area air quality to wildfire smoke. IEM is the archive, not the official system of record.

Agency and publisher pages 1

What remains uncertain

Status and provenance

Agency determination A government body issued a record naming this cause for this event: an NWS air-quality alert, a NOAA Storm Events record, or a state or local official archive.

This episode was grouped from the monitor record by the catalog pipeline and given its cause from the evidence listed above. It has not been individually reviewed and signed off, so its boundaries, cause, and name may change as evidence accumulates. Grouping policy common_sense_root_cause_grouping.v2. The cause label reflects the assembled evidence above, not an IAQng detection formula. If it is wrong, tell us.