Monitoring-site mix and PM2.5 trends in Los Angeles County (2015–2024)

Archived study

Compares Los Angeles County’s changing EPA monitoring network with six fixed sites during 2015–2024. The observed-network annual mean fell by 0.15 µg/m³, while the fixed-site mean rose by 0.81 µg/m³, showing that site membership affects the apparent change.

Interpretation and limits

These equal-site averages describe monitoring results, not population exposure or regulatory compliance. Comparing 2015–2017 with 2022–2024 gave declines in both networks; coverage assumptions and the comparison window affect the conclusion.

Package and provenance

The unchanged research package comes from upstream Case 10. It includes the archived session, analysis materials, results and figures. The poster uses an AI-generated illustrative photograph. This introduction summarizes archived findings; the analysis was not rerun.

Import provenance

This case was added to the Academic Research category on 2026-10-13, with the archived upstream case recorded as its source. The supplied session export and poster were uploaded without changing their contents. This introduction summarizes the archived findings and was standardized for the repository. The study, external data sources, and scientific results were not rerun or independently reverified for this import.

This GitHub catalog imports the case from the verified Hugging Face snapshot. The session export is referenced through that fixed revision; the cover and introduction are stored in this repository.

Case files

• Session export
• Case poster