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Air Atlas–Estimated Visibility

Estimated visibility statistics for the 2008–2012 time period are shown on the map below:

  • Visibility on the 20% Clearest Days – days with the least impairment.
  • Visibility on the 20% Haziest Days – days with the most impairment.
  • Average Visibility minus Natural Conditions – the difference between current visibility and unimpaired visibility.

Click the map legend to turn parks, monitors, or visibility statistic layers on and off. Click on parks on the map to find park specific estimates of visibility statistics. Visibility estimates are also avaiable in table form (pdf, 514 KB). Visibility estimates are based on air quality data from monitors in the Interagency Monitoring of Protected Visual Environments (IMPROVE) network.

What is Visibility?

Visibility is our ability to clearly see color and detail in distant views. Many visitors come to National Park units to enjoy beautiful scenic views. Unfortunately, these views are sometimes obscured by haze. Haze results from air pollutants, such as fine particles that absorb and scatter sunlight. Both natural and manmade sources contribute to haze-causing particles and gases in the atmosphere. visibility effects »

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Last Updated: June 21, 2016