This demo shows a map of the U.S. depicting the Clean Air Status and Trends Network (CASTNET) Ozone monitoring stations and their average Ozone level.
Clicking a station shows more detailed information and a link to a graphical representation of the time-series of measurements.
This demo is based on the following datasets from US government:
Dataset 8: Clean Air Status and Trends Network (CASTNET): Ozone (from data.gov)
Dataset 10001: Castnet site information (from epa.gov but not from data.gov)