People in the San Antonio area of Texas have been urged to find alternatives to using their cars because of high levels of ozone air pollution.
The Texas Commission on Environmental Quality (TCEQ) issued an Ozone Action Day for Wednesday, saying “atmospheric conditions are expected to be favorable for producing high levels of ozone air pollution.”
It said: “You can help prevent ozone pollution by sharing a ride, walking or riding a bicycle, taking your lunch to work, avoiding drive-through lanes, conserving energy and keeping your vehicle properly tuned.”
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This is one of at least two times this month that Texans have been asked to stop driving their cars. El Paso residents were urged to help with high ozone levels for a few days on August 1.
It is possible that Thursday may be another Ozone Action Day for Texas. If this is the case, the TCEQ will issue a notice by 3:00 p.m. on Wednesday.
The TCEQ explains on its website that ozone, or smog, is a gas formed in the atmosphere and that “summer days in Texas can be conducive for ozone formation as high-pressure systems dominate local weather patterns, giving [the state] clear skies and stagnant winds.”
“Ozone mainly forms in the highest concentrations on warm, sunny days with light wind speeds and low relative humidity which allows more of the pollutant to form and accumulate,” it added.
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Motor vehicle exhaust and gasoline vapors are some of the major sources of nitrogen oxides (NOx) and volatile organic compounds (VOCs)—with the chemical reaction between them causing ground-level ozone when in sunlight.
The TCEQ says: “Ground-level ozone is of particular importance because it is a respiratory toxic agent that can cause acute respiratory health effects when people breathe high concentrations of it over several hours. These effects include decreased lung function and pain with deep breaths, and aggravated asthma symptoms.”
Meteorologists declare ozone action days on a day-to-day basis. The Ozone Forecast Season starts on April 1 and ends on October 31 for Austin, Corpus Christi, San Antonio and Victoria.
The season for El Paso and Beaumont-Port Arthur also ends on October 31, but it starts a month later on May 1. Meanwhile, Dallas-Fort Worth’s starts on March 1 and ends on October 31.
Houston’s is from March 1 to November 30 and Tyler-Longview’s is from May 1 to September 30.
Other parts of the country have also asked people to help manage high levels of ozone, including in Oklahoma, where an Air Quality Alert has been issued for Wednesday.
It covers the cities of Guthrie, Yukon, Concho, El Reno, Mustang, Oklahoma City, Chandler, Stroud, Prague, Meeker, Davenport, Wellston, Chickasha, Tuttle, Purcell, Newcastle, Blanchard, Norman and Moore.
The Oklahoma Department of Environmental Quality said: “The general public is encouraged to help alleviate the problem by reducing vehicle miles traveled by riding the bus…carpooling…or avoiding unnecessary trips.
“The public is also asked to avoid refueling during the morning and early afternoon hours…and to avoid the use of two-cycle engines such as lawn mowers… motorcycles…weed trimmers…and outboard engines. It is also advised to limit outdoor burning.”
