← Air events

Wildfire smoke Possible

2000-02-10 Orlando-Kissimmee-Sanford, FL wildfire-smoke episode

February 10, 2000

Daily PM2.5 peaked at 34.2 µg/m³ near Orlando across 1 covered metro home to 2.9 million people.

Counting the extra PM2.5 above each metro's typical day, this event handed the average affected resident ≈ 1.2 cigarettes. Across everyone living in the affected metros, that is the collective equivalent of ≈ 3.6 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 same-day Melbourne discussion reports that haze and smoke from scattered brush fires were obscuring east-central Florida skies while the Orlando episode was measured. The date, place, and stated limitations support possible confidence only.

Possible This is a transparent hypothesis supported by limited evidence or an explicit inference, not a definitive attribution.

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

    The same-day Melbourne discussion reports that haze and smoke from scattered brush fires were obscuring east-central Florida skies while the Orlando episode was measured.

    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

    34.2 µg/m³ near Orlando

    EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 1.6 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

Orlando-Kissimmee-Sanford, FL

Monitor comparison window 2000-02-07 to 2000-02-13 · PM2.5 target: Primrose Ave

6 pollutant signals
Fine-particle pulse 33.6 µg/m³

53% above nearby days

PM10 30 µg/m³

36% higher than surrounding days

Pollution fingerprint

Metro-wide median of reporting monitors
PM2.5 33.6 µg/m³

53% higher than surrounding days

Before20.1 µg/m³ Event33.6 µg/m³ After22 µg/m³
3 monitors · 24 HOUR
PM10 30 µg/m³

36% higher than surrounding days

Before20 µg/m³ Event30 µg/m³ After23 µg/m³
1 monitor · 24-HR BLK AVG
Carbon monoxide 1.28 ppm

About the same as surrounding days

Before1.14 ppm Event1.28 ppm After1.26 ppm
2 monitors · 1 HOUR
Nitrogen dioxide 28.3 ppb

7% higher than surrounding days

Before24.9 ppb Event28.3 ppb After32.5 ppb
1 monitor · 1 HOUR
Sulfur dioxide 2.83 ppb

21% higher than surrounding days

Before1.71 ppb Event2.83 ppb After2.33 ppb
1 monitor · 1 HOUR
Ozone 0.043 ppm

40% higher than surrounding days

Before0.030 ppm Event0.043 ppm After0.030 ppm
4 monitors · 8-HR RUN AVG BEGIN HOUR

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
Orlando-Kissimmee-Sanford, FL 34.2 µg/m³ 1.6 Feb 10, 2000 #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.

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.

1 retained source

Official record

Area Forecast Discussion: haze and smoke from scattered regional brush fires

National Weather Service Melbourne via Iowa Environmental Mesonet

The same-day Melbourne discussion reports that haze and smoke from scattered brush fires were obscuring east-central Florida skies while the Orlando episode was measured.

What it supports

An official source supports the attributed cause for the stated place and dates.

Limit

The discussion does not identify the fires or establish whether each fire was wild, agricultural, or prescribed; wildfire_smoke is therefore a broad wildland-fire category at possible confidence.

What remains uncertain

Status and provenance

Possible This is a transparent hypothesis supported by limited evidence or an explicit inference, not a definitive attribution.

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.