Home page contents
- See today's Air Quality Index
- Section 1 - I thought ozone was a good thing?
- Section 1.2 - Where does ground-level ozone come from?
- Section 1.3 - 2012 Ozone Action Day Stats
- Section 2 - What are the effects of ground-level ozone?
- Section 2.1 - Health hazards
- Section 2.2 - Damage to the environment
- Section 3 - What can I do to help?
- Section 3.1 - Smarter Transportation
- Section 3.2 - Energy Conservation
- Pledge - Do your part!
It is – when it’s in the upper atmosphere. Ozone (abbreviated O3) is a colorless, odorless gas composed of three atoms of oxygen.
Ozone occurs naturally in the upper atmosphere, shielding the earth’s surface from the sun’s harmful ultraviolet rays.
However, when ozone forms closer to the ground, in the troposphere, it can cause big problems.
While some NOx and VOCs are naturally occurring (biogenic), most are manmade (anthropogenic). For example, emissions from power plants, factories, and vehicles, along with fumes from paints, solvents, and fuels, contain NOx and VOCs. Central Texas has no shortage of sunny days, especially from April through October when high levels of O3 are most likely to occur.
# of unhealthy ozone days in central texas (2012)
Unhealthy ozone days in 2012
- January – 0
- February – 0
- March – 3
- April – 14
- May – 8
- June – 9
- July – 1
- August – 11
- September – 7
- October – 1
- November – 0
- December – 0
What is an unhealthy ozone day?
Poor air quality is a health concern, especially for people with respiratory illness. Even an Air Quality Index (AQI) of “Moderate,” can affect those who are unusually sensitive to air pollution.
Let's put this into perspective
days in 2012 were
unhealthy ozone days
this is nearly a seventh of the year!
|of the unhealthy ozone days were between april and october|
Even at relatively low levels, ground-level ozone can be harmful to human health and the environment. It is especially a problem in urban and suburban communities; however winds can carry ozone precursor-emissions many miles from their original sources, affecting rural areas as well.
Children are at the greatest risk, because of their developing lungs and frequent outdoor activity. Anyone with a compromised respiratory system is especially vulnerable to ozone. Even healthy adults can be affected when working or playing outdoors.
- Difficulty breathing deeply and vigorously
- Sore or scratchy throat
- Inflamed and damaged airways
- Shortness of breathes and pain when taking a deep breath
- Aggravation for lung diseases like asthma, emphysema, and chronic bronchitis
- Increased frequency of asthma attacks
- Greater susceptibility to lung infection
- Continued damage to the lungs even after symptoms have disappeared
Ground-level ozone damages vegetation and ecosystems. It interferes with the ability of sensitive plants to produce and store food, reducing their growth and increasing their susceptibility to disease.
It is not just ecosystems that are affected by ozone; the built-environment suffers, too. Surfaces of buildings, statues, and monuments can degrade when exposed to ozone.
These effects can degrade ecosystems, changing habitat quality and risking loss of species diversity in parks, forests, wildlife refuges, and wilderness areas.
Remember, the equation for ozone is NOx + VOC + Sunlight. We can’t change our beautiful Texas sunshine, but there are simple ways we can reduce the amount of NOx and VOC in the environment. Smarter transportation is key. In Central Texas, almost half of our NOx emissions are from cars and trucks.
Reducing energy consumption at home and work helps reduce the NOx and VOC emissions that come from electricity generation.