Satellite data could improve Air Quality Index
- By Mike Cipriano
- Apr 11, 2014
Combining air quality data from NASA satellites with data from the Environmental Protection Agency’s AirNow service can deliver a number of potential community-level and economic benefits, according to a study from the Center for Technology in Government at the University at Albany.
The EPA, National Oceanic and Atmospheric Administration, the National Park Service, and tribal, state and local agencies developed the AirNow website to provide the public with easy access to national air quality information.
It provides both daily forecasts and hourly data using the Air Quality Index for over 300 cities across the United States, and provides links to more detailed state and local air quality Web sites. The site also presents maps of AQI levels on national, regional and local spatial scales.
The air quality sensor network does not cover significant areas of the continental United States, however, leaving approximately 42 million people with no information or inaccurate data. One of the potential benefits satellite data could bring to AirNow is filling in these gaps in the ground sensor network. Officials in Kansas City, Mo. noted that, “we’re missing a better understanding of how much emissions in rural areas and upwind transport impact largely urban nonattainment areas.”
One way to provide additional information on particulate matter for these unmonitored areas is to use satellite aerosol optical depth data. A recent NASA-funded project, AirNow Satellite Data Processor (ASDP), developed a system for EPA to routinely estimate surface concentrations of particulate matter from satellite data and then fuse these estimates with routine surface observations in the AirNow system.
In addition, satellite data could improve regional and local analysis of air quality conditions. State and local governments would have more accurate and timely information to use for air quality forecasting, budgeting and public health and policy research. Near-real-time data would also help local agencies issue advisories for events such as smoke from fires.
Using satellite data is significantly more cost effective than installing additional ground monitors in uncovered areas, the report argues. Satellite data could provide daily pollutant information to 82 percent of people living in unmonitored areas at little to no cost. Installing 74 additional ground monitors in areas with 25,000 or more residents would cost nearly $26 million, while only providing coverage to 44 percent of people in these locations.
“This study showed that users with different needs and capabilities can all benefit from enhanced air quality data,” said CTG Study Director Sharon Dawes. “Equally important, the study findings emphasize the importance of stewardship in ensuring the usability, usefulness and value of any public data. When people understand the data sources, precision, timeliness and format, they can use it for diverse benefits to individuals, groups and society.”
The study was conducted using two methods: face-to-face interviews with experts in three locations (Denver, Atlanta and Kansas City, Mo.) to evaluate the community-level benefits and a cost-saving analysis of using satellite data over installing additional ground monitors.