Superstition Mountains
The Superstition Mountains are part of the designated Superstition Wilderness Area. The view is looking east from downtown Mesa with the community of Apache Junction between the camera and the mountain vista.
Superstition Mountains Gallery
To secure a representative gallery of observed air quality conditions for each scene monitoring site, a series of images are selected from the period of record and archived in several resolutions as an Image Gallery set.
The series of images making up the historical image gallery typically consists of:
- Image spectrum consisting of a series of Excellent to Very Poor regional haze conditions, corresponding to deciview increments of the Visibility Index scale.
- Seasonal images representative of pristine, scenic, or meteorological interest.
- Unique representations of layered haze, regional haze, or pollution episodes of significant importance.
The Superstition Mountains image images gallery was last updated in May 2004. Check this page again for future updates.
"High Pollution Advisory" or "HPA" means the highest concentration of pollution may exceed the federal health standard. Active children, adults and people with lung disease such as asthma should reduce prolonged or heavy outdoor exertion.
Causes of Poor Visibility
Extremely small particles are the principal cause of poor visibility. These tiny particles, too small to be seen without a microscope, are measured in microns, with one micron equal to about one-seventieth (1/70) of the diameter of a human hair.
Particulate matter less than 2.5 microns, often referred to as PM2.5, is a significant cause of haze. Each particle, about the size of a single grain of flour, can float in the atmosphere for days, behaving much like a gas. Over half of the PM2.5 in Phoenix is caused by the burning of gasoline and diesel fuel in vehicles (sometimes referred to as on-road mobile sources) and in off-road mobile sources, such as construction equipment like loaders and bulldozers, locomotives, lawn mowers, leaf blowers, and other devices that emit air pollution as they move1. PM2.5 particles containing carbon, like soot from tail pipes, are particularly effective in reducing visibility because they both scatter and absorb light.
Nitrogen dioxide and sulfur dioxide gases from burning of fossil fuels also contribute to the brown cloud. Nitrogen dioxide gas is brown, giving that color to the haze. Chemical reactions in the atmosphere convert these gases to fine particles.
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Forecast Discussion:
Ozone levels once again exceeded the federal health standard yesterday, this time only at two monitors in the northeast part of the Valley. Today, a trough moving into the region will bring some breezy winds, which should help lower ozone levels. We are forecasting ozone to drop into the upper Moderate AQI range today for the first time in a few days. Unfortunately, winds look to be calmer tomorrow, which may allow ozone to jump right back into the Unhealthy for Sensitive Groups AQI category. Therefore, we are issuing an Ozone High Pollution Advisory for Saturday. Looking ahead to Sunday and into early next week, we are forecasting better winds and ventilation from a large low pressure system over the Pacific Northwest. We are forecasting this to provide enough ventilation to keep ozone level in the upper Moderate AQI range for the remainder of the forecast period.
As for particulates, both PM10 and PM2.5 ended up in the Good AQI range yesterday. However, looking at PM10 concentrations this morning, there is potential to reach back into the low Moderate category...
Today's Air Quality Forecast
Air Quality Year-to-Date Report
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