LADCO Exceptional Events

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Data and resources for supporting exceptional events analysis for the LADCO member states.

LADCO Screening Metric

Jump to the LADCO screening metric results

The LADCO Exceptional Event screening analysis focused on finding signals in standard surface monitoring data to identify when there is potential for smoke influences on surface air quality conditions during the ozone season

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Resources

The following data are being used by LADCO for screening air quality data.

• Airnow Tech is the first tool to use for this triage analysis. Tutorial below for creating (1) ozone timeseries and (2) ozone, smoke, and back trajectory maps
• NC DNR Online GIS tool for displaying draft DVs and critical values.
• LADCO Design Value Tracker for tabulated ozone concentrations by site in the different O3 NAAs in the region
• EPA EE information, guidance, and additional data sources
  • EPA Exceptional Events Web Page: Main landing page for EPA guidance
  • Exceptional Events Rules and Guidance: Subpage of the above with links to FR notices, fact sheets, and guidance
  • 2016 Exceptional Events Rule FAQS: Frequently asked questions on technical and procedural issues
  • AQS Exceptional Events Tutorial: User’s guide-like guidance for how to flag EE days in AQS
  • EPA Example EE Demonstrations

LADCO Technical Support Documents

• June 2024 Regional TSD

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State Exceptional Event Demonstrations

Year	Location	Description
2021	IL	Chicago NAA June 2020 exceptional event demonstration submitted to U.S. EPA on February 1, 2021 | US EPA TSD to support non-concurrence
2021	OH	Cincinnati June 2020 ozone exceptional event demonstration submitted to U.S. EPA on April 13, 2021 | US EPA TSD to support non-concurrence
2021	MI	2020 Western MI demonstration draft submitted to U.S. EPA on March 24, 2021
2016	N/A	U.S. EPA Exceptional Events Submissions Table (2016 Rule)
2017	CT	CT DEEP May 2016 Ozone Exceptional Event Analysis Technical Support Document
2017	OH	OH EPA May 2016 Canadian Wildfire Ozone and PM2.5 Exceptional Event Demonstration
2018	LA	LA DEQ September 2017 Ozone Exceptional Event Technical Support Document  | EPA Webpage for LA EE Demo
2018	N/A	STI presentation to LADCO on Baton Rouge Exceptional Event Demonstration (July 10, 2018)
2013	ID	Request for EPA Concurrence as Exceptional Events for 2012 Wildfire Impacts on PM2.5 Monitor Values at Salmon and Pinehurst Idaho (December 6, 2013) | Salmon Addendum (April 25, 2014) | US EPA Concurrence Analysis (July 8, 2014)

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Analysis Guidance

First Tier Data

User friendly, distilled data for screening air quality data; good for first level analysis

AirNow Tech
Password protected web client available to air planning agency staff. Access to near-real time surface obs and smoke data. Key features

• Create timeseries of O3 and PM surface data for individual monitors.
• Overlay maps with surface pollutant concentrations and smoke plumes.
• Create back or forward trajectories at monitors, overlaid on maps
• Download observational data, figures, and maps of analysis products

AirNow
Public web client with access to near real time air quality index and smoke data

NASA Earthdata Atmosphere
Public web client interface to remote sensing data, such as aerosol optical depth and pollution column retrievals

NOAA Air Quality and smoke forecasts
Maps of NOAA air quality, smoke, and dust forecasts

NOAA Hazard Mapping System smoke maps
Maps of smoke plumes from NOAA’s HMS. Historical archive of KMZ and Shapefiles of HMS smoke and fire.

NASA Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) 
Satellite derived vertical profiles of clouds and aerosols in the atmosphere. Historical archive of KMZ profiles.

NOAA High Resolution Rapid Refresh (HRRR) smoke model
Static and interactive maps of modeled hourly smoke forecasts, including surface smoke product

Environment Canada smoke and air quality forecasts
Maps of Canadian air quality and smoke modeling forecasts

Ventusky
Modeled and observational data of meteorology and chemistry parameters.

Second Tier Data

Low level and raw observational and remote sensing data; good for deep dive into remote sensing data

Remote Sensing Information Gateway
Desktop client for accessing EPA modeling data, remote sensing data, and surface obs

NASA GIOVANNI
Web client for accessing raw remote data from many of NASA’s atmospheric science remote sensing assets.