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Prescribed fire Possible

2003-05-30 Palm Bay-Melbourne-Titusville, FL prescribed-fire smoke episode

May 30, 2003

Daily PM2.5 peaked at 24.7 µg/m³ near Palm Bay across 1 covered metro home to 658,447 people.

Why we think this happened

The basis for “Prescribed fire”

Melbourne's airport reported smoke during the PM2.5 event. The Florida Forest Service exact-date Orlando District report lists seven authorizations in Brevard County and additional authorized burn acreage in Orange and Osceola counties. This makes controlled vegetation burning a reasonable broad estimate, but the report does not establish which authorizations were exercised or connect one to the monitor.

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

NOAA/NWS surface observations via Iowa Environmental Mesonet · May 30, 2003 hypothesis

MELBOURNE REGIONAL surface observations reporting smoke

MELBOURNE REGIONAL, 5.7 km from the PM2.5 target monitor, reported the official present-weather code FU (smoke) during 1 observed hour inside the catalog event window.

Inference, not direct attribution

official_surface_smoke_plus_exact_date_burn_authorizations_possible.v1: This inference is recorded in the catalog methodology.

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

    Pattern-based explanation

    official_surface_smoke_plus_exact_date_burn_authorizations_possible.v1. This inference is recorded in the catalog methodology.

    Inferred
  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

    24.7 µg/m³ near Palm Bay

    EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 1.1 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 “Prescribed fire” explanation; it does not assign the cause by itself.

Observed context · not attribution

Palm Bay-Melbourne-Titusville, FL

Monitor comparison window 2003-05-27 to 2003-06-02 · PM2.5 target: Melbourne

3 pollutant signals
Fine-particle pulse 24.7 µg/m³

89% above nearby days

PM10 31 µg/m³

About the same as surrounding days

Pollution fingerprint

Metro-wide median of reporting monitors
PM2.5 24.7 µg/m³

89% higher than surrounding days

Before8 µg/m³ Event24.7 µg/m³ After13.1 µg/m³
1 monitor · 24 HOUR
PM10 31 µg/m³

About the same as surrounding days

Before19 µg/m³ Event31 µg/m³ After30 µg/m³
1 monitor · 24-HR BLK AVG
Ozone 0.067 ppm

61% higher than surrounding days

Before0.035 ppm Event0.067 ppm After0.041 ppm
2 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
Palm Bay-Melbourne-Titusville, FL 24.7 µg/m³ 1.1 May 30, 2003 #15 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.

2 retained sources

Official record

MELBOURNE REGIONAL surface observations reporting smoke

NOAA/NWS surface observations via Iowa Environmental Mesonet

MELBOURNE REGIONAL, 5.7 km from the PM2.5 target monitor, reported the official present-weather code FU (smoke) during 1 observed hour inside the catalog event window.

What it supports

This source supports a possible mechanism or occurrence; it does not establish the cause by itself.

Limit

The surface code establishes smoke at the nearby airport; it does not identify whether the source was a wildfire, prescribed burn, agricultural fire, or another local fire.

Official record

Orlando District burning authorizations for May 30, 2003

Florida Forest Service

For May 30, 2003, the Florida Forest Service Orlando District report lists seven burn authorizations in Brevard County, 13 authorizations covering 106 acres in Orange County, and 12 covering 746 acres in Osceola County.

What it supports

Context for the event; this item does not establish the attributed cause by itself.

Limit

The public report records authorizations, not proof that every authorized burn was carried out.

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.