Great Lakes Network
The Great Lakes Vital Signs Network (GLKN) consists of nine national park units in four states adjacent to Lakes Superior and Michigan. The parks represent the major freshwater ecosystems of the Upper Great Lakes and, therefore, aquatic ecosystems comprise an important component of all nine park units. Isle Royale and Voyageurs National Parks (NP) are designated Class I air quality areas; the rest of the Network parks are Class II air quality areas.
Indiana Dunes National Lakeshore (NL) and Isle Royale and Voyageurs NPs have on-site ambient air quality monitoring; the rest of the parks have monitors nearby. The air pollutants of greatest concern for the GLKN are mercury and other toxic air pollutants. In addition, both Indiana Dunes and part of Sleeping Bear Dunes NLs are in proposed 8-hour ozone non-attainment areas. An ozone injury risk assessment indicates the risk of injury is moderate to high in Indiana Dunes, Pictured Rocks, and Sleeping Bear Dunes NLs.
The Network map below provides information on air quality monitoring. Ozone, sulfur dioxide, dry deposition, and meteorology are collected by the Clean Air Status and Trends (CASTNet) and Gaseous Pollutant Monitoring (GPMN) networks. Ozone is also monitored with passive samplers and portable continuous analyzers. Wet Deposition is monitored through cooperation with National Atmospheric Deposition Program/National Trends Network (NADP/NTN). The Mercury Deposition Network (MDN), part of NADP, collects precipitation samples that are analyzed for mercury. Visibility is monitored as part of the Interagency Monitoring of Protected Visual Environments (IMPROVE). Additional details on these parameters are described in Air Quality Monitoring.
Air quality monitoring in or near the network is indicated on the map by symbols, with the blue line showing the approximate borders of the network. The legend shows the symbols for the type of monitoring present, with NPS park units in green. Class I areas have linkable access to ARIS information.