Prescribed fire Possible
Daily PM2.5 peaked at 41.3 µg/m³ near Augusta across 1 covered metro home to 636,760 people.
Why we think this happened
Exact-date NWS discussions place regional prescribed-burn or wildfire smoke over the Augusta forecast area while EPA monitors record a local PM2.5 episode. A same-place, same-year permit-based study independently shows that March prescribed burning materially affected Augusta in 2018. Together these support prescribed-fire smoke only at possible confidence because the official forecast preserves wildfire ambiguity, says smoke may have remained aloft, and no exact-day burn-to-monitor attribution exists.
Possible This is a transparent hypothesis supported by limited evidence or an explicit inference, not a definitive attribution.
National Weather Service Columbia via Iowa Environmental Mesonet · Mar 16, 2018 hypothesis
NWS Columbia reported that smoke from regional prescribed burns could reduce visibility, mainly aloft, in the near term for the Augusta forecast area.
National Weather Service Columbia via Iowa Environmental Mesonet · Mar 16, 2018 hypothesis
A later NWS Columbia discussion again warned that smoke from prescribed burns or wildfires could reduce visibility in parts of the forecast area in the near term.
U.S. EPA AirData hypothesis
EPA records show a daily PM2.5 value of null micrograms per cubic meter across 2 Augusta-area monitors on March 17, compared with 11.8 before and 10.85 after the event.
Inference, not direct attribution
official_smoke_forecast_plus_local_seasonal_fire_evidence_possible.v1: This inference is recorded in the catalog methodology.
Evidence path
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.
Source or mechanism
official_smoke_forecast_plus_local_seasonal_fire_evidence_possible.v1. This inference is recorded in the catalog methodology.
Air-mass movement
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.
Local response
EPA monitors recorded the event across 1 metro. The peak daily concentration is roughly 1.9 cigarette-equivalents at the outdoor daily rate.
Inspect the pollutant and weather signals ↓Event autopsy
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.
Augusta-Richmond County, GA-SC
Monitor comparison window 2018-03-14 to 2018-03-20 · PM2.5 target: Augusta
259% above nearby days
7 calm hours observed
1 hours at or below 3 miles
259% higher than surrounding days
138% higher than surrounding days
31% higher than surrounding days
39% lower than surrounding days
9 kt maximum · 7 of 24 observed hours calm
1 observed hours at or below 3 miles
53°F to 74°F
90% maximum
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.
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.
| Metro | Peak PM2.5 | Cigarettes, whole event | Peak day | All-time standing |
|---|---|---|---|---|
| Augusta-Richmond County, GA-SC | 41.3 µg/m³ | 1.9 | Mar 17, 2018 | #24 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
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.
National Weather Service Columbia via Iowa Environmental Mesonet
NWS Columbia reported that smoke from regional prescribed burns could reduce visibility, mainly aloft, in the near term for the Augusta forecast area.
This source supports a possible mechanism or occurrence; it does not establish the cause by itself.
The forecast said the smoke could remain mainly aloft and did not quantify its contribution to Augusta surface PM2.5.
National Weather Service Columbia via Iowa Environmental Mesonet
A later NWS Columbia discussion again warned that smoke from prescribed burns or wildfires could reduce visibility in parts of the forecast area in the near term.
This source supports a possible mechanism or occurrence; it does not establish the cause by itself.
The source explicitly preserves prescribed-fire versus wildfire ambiguity and does not establish surface attribution at the Augusta monitor.
U.S. EPA AirData
EPA records show a daily PM2.5 value of null micrograms per cubic meter across 2 Augusta-area monitors on March 17, compared with 11.8 before and 10.85 after the event.
This source supports a possible mechanism or occurrence; it does not establish the cause by itself.
The monitor record establishes the particle episode but cannot identify the particle source by itself.
U.S. EPA EQUATES CMAQ via Remote Sensing Information Gateway
EPA's retrospective model reproduced an event-day fine-mass increase of 1.7512 times adjacent modeled days; organic matter represented 58.1 percent of modeled fine mass.
Context for the event; this item does not establish the attributed cause by itself.
EQUATES is modeled composition context, not a monitor observation or a prescribed-fire source-apportionment result.
Huang et al., International Journal of Environmental Research and Public Health
A peer-reviewed Georgia study using state burn permits and modeled fire impacts found Augusta among the metros with substantial prescribed-fire PM2.5 influence, identified March as the most active burning month, and found 2018 had the largest modeled burn impact of the four years studied.
Context for the event; this item does not establish the attributed cause by itself.
The study establishes a same-place, same-year seasonal pattern, not the source fraction for March 17 or a match to one specific burn.
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.