Abstract:
This data set contain the yearly data by season for the IMPROVE
Program monitoring sites.
IMPROVE, or the Interagency Monitoring of Protected Visual
Environments Program, is helping the National Park Service (NPS) and
other Federal Land Managers to protect visibility at 156 national
parks and wilderness areas (Class I Areas)as required by the Clean Air
Act. IMPROVE has representatives from the
... NPS, the Forest Service
(USFS), the Bureau of Land Management, the Fish and Wildlife Service
(FWS), the Environmental Protection Agency, and regional-state
organizations. Activities include research on all aspects of the
visibility issue, design and operation of a long-term visibility
monitoring program, development of standard air quality/visibility
simulation models for predicting new source impacts, and development
and implementation of national visibility protection
policies. Specifically, the IMPROVE program includes the
characterization of the haze by photography, the measurement of
optical extinction with transmissometers and nephelometers, and the
measurement of the composition and concentration of the fine particles
that produce the extinction and the tracers that identify emission
sources.
This coverage contains point locations of all Class I areas within the
conterminous United States. 
