The graphic on this page shows a summary of visibility trends on NWPS-managed wilderness areas. Each wilderness area has a row of cells representing up to 26 years of trends in visibility at the nearest station. If enough data is available to calculate a trend, the cell for that year is shaded to indicate an increasing, decreasing, or stable trend.

Hover over a cell to show trend information for the available period of record up to that year. Click any trend cell to explore trends at ozone stations around that wilderness.

Visibility trends are available for wilderness areas managed by the Forest Service, Bureau of Land Management, National Park Service, and Fish and Wildlife Service.