Ozone Monitoring
Overview
The GPMP historically concentrated on determining the levels of two gaseous air pollutants, ozone and sulfur dioxide, which can be toxic to native plants. Other gaseous pollutants (e.g., other photochemical oxidants, nitrogen compounds, and toxic organic compounds) are also of interest to the NPS because they relate to physiological, morphological, or historical injury to park biological resources, or to global climate change. Ozone and sulfur dioxide monitoring studies in national parks have been ongoing since the early 1980s. These studies use EPA reference or equivalent methods, allowing for the direct comparison of NPS data with data collected by state and local air pollution control agencies and the EPA. Limited studies have also measured other gaseous pollutants within the National Park System.
- Locations
- Data Access
- Results
- Procedures
- Contacts
Monitoring Locations
Most NPS ozone monitoring locations are operated by the NPS in parks identified as mandatory Class I areas. Class 1 areas, defined by the Clean Air Act, are held to a higher air quality standard than other areas. Some ozone monitoring stations in the parks are operated by State agencies.
- List of active monitoring stations
This table identifies active monitoring stations and parameters measured. - Monitoring History Database
Air quality parameters have been measured in parks since 1987 - the database provides details on what has been measured at each location.
Data Access
| DataType | Details | Access Data |
|---|---|---|
| Metadata | what, where, and when monitors have operated in national parks | Monitoring History Database |
| NPS Gaseous Pollutant & Meteorology | ozone and sulfur dioxide (for a limited number of parks) hourly concentrations; wind speed and direction, temperature, relative humidity, precipitation, solar radiation, and wetness at NPS sites | Interactive Data Query – includes summary tables and plots |
| CASTNET data | ozone hourly concentrations, meteorology, and filter-pack data at all CASTNet sites | CASTNet website |
| Real-time Scenic and Air Quality Conditions | current on-line scenic views, ozone, PM2.5, and/or meteorological data | Web Cameras |
| Current Ozone & Weather Data | current 1-hour average ozone concentration, wind speed and direction, temperature, relative humidity, solar radiation, and rainfall for NPS sites (available May - September only) | Current Ozone & Weather Data |
| Health Advisories | current health advisories, available May - September | Health Advisories |
| ozone health advisory summaries | Ozone Health Advisory Summaries | |
| Ozone Standard Exceedances | park list of ozone standard exceedances by month and year (2000 - present) | Ozone Standard Exceedances |
| Current Map of Ozone Data | map of current ozone data at NPS sites (available May - September only) | EPA AIRNow - Air Quality Index |
| Criteria Pollutants & Meteorology | ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, lead, PM10, PM2.5, and meteorology annual summaries | EPA Annual Summary Tables |
Results
NPS Ozone monitoring data summaries, analysis, and results are made available as reports, through Air Atlas, and other publications.
- 2007 Annual Data Summary Report (pdf, 1.4 mb)
- 2006 Annual Performance and Progress Report (pdf, 1.7 mb)
- Annual Data Summary Reports. Also available – 2007 Data Quality Assurance Report.
- Current year summary tables of 2007 high ozone concentrations and exceedances of the National Ambient Air Quality Standard (NAAQS) based on screened preliminary data. Preliminary data are used to get a quick look at the high 8-hour ozone averages that exceed 85 ppb.
- Exceedances of the ozone standard of 85 ppb, 2007 (pdf, 155kb)
- List of parks where ozone standard is violated, 2007 (pdf, 42kb)
- Resource injury ozone indices table and map, 2007 (pdf, 191kb)
- Implications to the NPS of the New 76 ppb Ozone Standard (pdf, 1.4mb)
Ozone trends are an important product of NPS monitoring. Summary data from the Quick Look Annual Summary Statistics Report and the Annual Data Summary Report can now be viewed with the web-based interactive trend plotter. The present air quality can be assessed in relation to the National Ambient Air Quality Standard. Trends can then be considered to determine an overall condition. For more detailed information, see the Annual Data Summary Reports and the 2006 GPRA Report (pdf, 740kb).
Publications Using NPS Data
- Surface ozone in Yosemite National Park. Burley, Ray. Atmospheric Environment 41, 6048-6062 (2007), (pdf, 816 kb)
- Increase in Surface Ozone at Rural Sites in the Western US. Jaffey, Ray. Atmospheric Environment 41, 5452 – 5463 (2007). (pdf, 390kb)
Procedures
The standard NPS monitoring station measures ozone using a UV–absorption analyzer, a transfer standard, a weather station including wind speed, wind direction, temperature at two heights, solar radiation, relative humidity, and a wetness sensor. Additionally a stacked filter-pack measures sulfate, sulfur dioxide, nitrate, ammonium, and nitric acid, and at some sites a sulfur dioxide. Park staff operate the stations and a contractor maintains and calibrates the network equipment. Data are transmitted nightly, validated, and archived. Hourly data files are transfered to the EPA Air Quality Systems database and are available on the web.
- Quality Assurance Plan (pdf 800kb) for the NPS gaseous pollutant monitoring network.
- Quality Management Plan (pdf, 300kb) for the NPS gaseous pollutant monitoring network.
- The on-line Standard Operating Procedures for site operators
of the monitoring stations. These are the procedures and forms used at the air quality stations in the NPS monitoring network.
- Ozone Monitoring Protocol for the Inventory and Monitoring program (pdf, 580kb)
Contacts
National Park Service, Air Resources Division staff – operations, contracts, analysis, and reporting, Denver, CO
- John Ray, Gaseous Pollutant Monitoring Program Manager (303) 969.2820
- David Maxwell, Monitoring Specialist (303) 969.2810
Air Resource Specialists – field support and data center contractor, Fort Collins, CO
- John Faust, Field Support Operations Manager (970) 484.7941
- Jessica Ward, Project Manager, Information Management Center (970) 484.7941
Additional Ozone Information
- Monitoring network overview This document lists the NPS monitoring objectives, the basics of the monitoring strategy, and information about the operation of the network. (pdf, 500kb)
- How the NPS ozone monitoring fits into US air quality monitoring is explained in a brochure.
- Related NPS ozone monitoring includes special studies programs using passive samplers, portable O3 monitors, and enhanced multi-pollutant analyzers.
- The US EPA has set an ozone national standand (NAAQS) of 75 ppb over an 8-hour period for human health and for natural resources. The standard is a calculated value over 3 years using the 4th highest annual ozone of the daily maximum 8-hour averages. See EPA for the full details.
- AirNow - Map of Todays' Ozone. Daily contour plots of ozone concentrations are available from AirNow.gov during the ozone season and include input from National Park Service monitoring stations. These maps are handy for understanding regional distributions and movements of ozone.
Monitoring Objectives
- Provide data to help scientists’ asses the risks that certain pollutants pose to natural resources in the parks.
- Collect air quality data in parks that reveals how well parks are doing with respect to the national ambient air quality standards set by the EPA. These data are also useful for EPA’s New Source Review permitting program and Prevention of Significant Deterioration program which seek to ensure that new and modified industrial development do not significantly degrade air quality.
- Identify air quality trends from measured data to aid in compliance predictions, policy objectives, and regional air quality assessments in areas that lack direct monitoring.
- Assist modeling efforts, regional pollution and transportation studies, State Implementation Plan development (to address regional haze), and national air quality control strategies through special studies.
- Provide timely NPS air quality information to the public and researchers.