O3 Increment from Prescribed Burns: Implications for Air Quality and Public Health in the Southeastern United States

Key numbers

• 0.9% of ambient levels
• 1.1% of ambient MDA1 O3
• 95% CI

Abstract Prescribed fire (PF) is extensively practiced across the southeastern United States (US) to maintain fire-adapted ecosystems and reduce wildfire risk. However, PF emits substantial quantities of ozone (O3) precursors that can elevate ground-level O3 through photochemical reactions. This study quantified PF contributions to ambient O3 and associated premature mortality across 12 southeastern US states from 2013 to 2021 using the Community Multiscale Air Quality (CMAQ) model at 12-km resolution. Model results were calibrated through data fusion with surface observations, and sensitivity to spatial resolution was examined with a nested 4-km simulation over Georgia. At 12-km resolution, contribution from PFs to daily maximum 8-h average O3 (MDA8 O3) concentrations averaged to 0.34 ± 0.12 ppb across the region, accounting for ∼0.9% of ambient levels. The PF contribution to daily maximum 1-h average O3 (MDA1 O3) averaged to 0.46 ± 0.18 ppb or ∼1.1% of ambient MDA1 O3. At state level, highest annual average PF-MDA8 O3 (0.59 ± 0.14 ppb) and PF-MDA1 O3 (0.84 ± 0.22 ppb) were estimated in Georgia. Seasonal peaks (January–April) coincided with higher burning activity, with PF-MDA1 O3 exceeding 1.0 ppb in Georgia, Alabama, Florida, and South Carolina. During the nine-year period, PF-related MDA8 O3 exposure (short-term + long-term) associated 8925 (95% CI: 6273–11,567) premature all-cause deaths, with 62% linked to long-term exposure. Florida (2618), Georgia (1465), and North Carolina (910) experienced the highest absolute mortality burdens. The 4-km resolution model performed better than the 12-km model in estimating MDA8 O3 concentrations. In Georgia, the 4-km simulation estimated approximately 10% lower PF-MDA8 O3 concentrations and, consequently, approximately 10% fewer PF-MDA8 O3-attributable premature deaths than the 12-km simulation. These findings highlight the regional health relevance of PF-related O3 and underscore the need to integrate air-quality and public-health considerations into future PF management, particularly under climate-driven increases in fire activity.

Kamal Jyoti Maji, Zongrun Li, Hu Yongtao, Jennifer Stowell, A. Vaidyanathan, Chad W. Milando, Gregory A. Wellenius, Patrick L. Kinney, Armistead Goode Russell, Mehmet Talat Odman

Leverage2 / 5

Reusable within one subfield (a technique, dataset, or protocol a few groups will adopt).

16% of this desk’s rubric

Magnitude3 / 5

Large gain: roughly 2x, or a clear new state of the art on a hard, unsaturated problem.

20% of this desk’s rubric

Evidence3 / 5

Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.

20% of this desk’s rubric

Novelty2 / 5

A new combination of known ideas.

10% of this desk’s rubric

Trajectory2 / 5

Some room to improve with obvious engineering.

14% of this desk’s rubric

Stakes3 / 5

Meaningful benefit to many people within a few years.

20% of this desk’s rubric

• Citations0 (reference 15, via openalex, Oct 31, 2026, 07:20 UTC)

• Reviewed by heuristic-v10 on Oct 31, 2026, 07:20 UTC. Paper type: empirical.
• Categories: Atmospheric chemistry and aerosols, Air Quality and Health Impacts, Fire effects on ecosystems, Atmospheric Science, Earth and Planetary Sciences
• BRIEF, No.7 in the Climate & Energy edition of October 31, 2026.