The South Coast Air Quality Management District (AQMD) has issued an ozone advisory as Southern California continues to grapple with the brutal heat wave sweeping across the region. The heat is leading to elevated levels of ozone smog in several inland areas.
The advisory, which is in effect from Tuesday through Friday, warns that air quality could reach unhealthy levels in parts of the South Coast Air Basin.
Excessive heat warnings are in place across much of the Southwest, including Arizona, California and Nevada, as temperatures continue to hit triple digits.
In response to the poor air quality, residents are being warned to take extra precautions, such as delaying trips to the gas station and not using household chemicals “until the evening.”
Getty/South Coast AQMD
The Air Quality Index (AQI) will likely reach “unhealthy or higher” levels in the Santa Clarita Valley, portions of the San Gabriel Valley, the San Bernardino Valley, and portions of the San Bernardino Mountains until Friday, the AQMD said in its announcement.
At such high levels, everyone could begin to experience adverse health effects, such as difficulty breathing and throat irritation. People with heart disease, pregnant women, children and older adults, and people with lung disease, such as asthma, should avoid prolonged time outdoors, according to AQMD guidance.
Other inland areas, such as Lake Elsinore, Corona, Hemet, and Pasadena, are expected to experience air quality that may be “unhealthy for sensitive groups,” including children, the elderly, and individuals with preexisting respiratory conditions.
Coastal areas are likely to be less affected due to cooler temperatures.
Newsweek reached out to the South Coast AQMD via email outside of regular working hours for further clarification on the ongoing situation.
South Coast AQMD
During the daytime, AQI levels are expected to rise after sunrise, peaking in the midafternoon before gradually decreasing in the evening.
Overnight and early-morning hours will bring some relief, with AQI levels forecast to fall into the Good to Moderate range. South Coast AQMD will provide updates if high ozone levels persist beyond Friday.
In response to the poor air-quality conditions, the South Coast AQMD urges residents to take precautions to protect their health.
People are advised to check air quality levels regularly and limit outdoor activities, particularly during peak ozone hours. Residents should also delay the use of gasoline-powered equipment; conserve electricity by setting air conditioners to a higher temperature; and try to postpone trips to the gas station and the use of household chemicals until the evening.
“Ozone is formed when several gaseous pollutants react in the presence of sunlight,” the AQMD said on its website.
Unlike ozone high up in the atmosphere—known as stratospheric ozone—which protects us from the sun’s harmful ultraviolet rays, ozone at ground level is a harmful pollutant.
It forms when nitrogen oxides and volatile organic compounds react. These chemicals are emitted by cars, power plants, industrial boilers, refineries and chemical plants, according to the Environmental Protection Agency.
Most of these gases are emitted from vehicles in California, the ADMQ said.
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