Air Quality Successes - Texas Compared to Other States

Texas’ air quality has made huge strides in the past few decades. The state has devoted significant resources for air monitoring and research to advance the science and find innovative ways to improve air quality.

Our Nation's Air by the US EPA

Click on image to enlarge it. Click again to close it. Right-click on large image to save it on your computer.

Ozone Trends

Texas showed a 32% decrease in ozone, the 10th largest decrease in the United States.
All other states averaged a decrease of 19%.
The eastern half of the US, plus Texas and California, had the largest decreases in ozone while the western US saw less of a decrease and even an increase in some states.
Values are based on the three-year average of the maximum fourth-highest eight-hour ozone concentration from all monitors operating within each state.

Eight-hour ozone design value trends of the five largest metropolitan areas

5 Largest Metro Areas

Texas has two of the most populous combined statistical areas (CBSAs) in the US.
The two areas in Texas, the Houston-Galveston-Brazoria (HGB) and the Dallas-Fort Worth (DFW) areas, have the first and the third largest percent decreases in ozone design values from 2000 through 2019, 29% and 25% respectively.
Of the five largest CBSA’s, the DFW area has the lowest eight-hour ozone design value in 2020.

Houston and Los Angeles eigght-hour ozone concentration trends

Ozone Concentrations

The fourth-highest eight-hour ozone concentrations for the Houston and Los Angeles CSA’s have trended lower from 2000 to 2020.
However, the fourth-highest ozone in Houston is decreasing at a faster rate of 36% compared to California, which has seen a 2% increase from 2000 through 2020.
In 2020, the fourth-highest ozone value was 50 ppb higher in Los Angeles than in Houston.

Air Quality Index (AQI) trends from 2000 to 2018 for Houston and Los Angeles

Houston vs Los Angeles AQI

The Air Quality Index (AQI) takes into account all criteria pollutants.
Houston has had many more good (green) days when compared to Los Angeles. Further, the number of good days has increased by 253% from 2000 through 2020 in Houston while the number of good days has increased by 122% over that same time in Los Angeles.
Houston’s air quality in 2020 was either good (green) or moderate (yellow) 93% of the time while Los Angeles had good or moderate air quality 61% of the time.

NO_X Emissions per Capita

Of the 20 states with the highest fossil-fuel fired power plant NO_X emissions, Texas ranks 8th lowest in emissions per capita.
Though Texas has the 2nd highest population among all states, emissions per person are low.
Emissions and generation data from the EPA Clean Air Markets for calendar year 2019.
Data current as of 07/11/2021

SO₂ Emissions per Capita

Of the 20 states with the highest fossil-fuel fired power plant SO₂ emissions, Texas ranks 10th lowest in emissions per capita.
Though Texas has the 2nd highest population among all states, emissions per person are low.
Emissions and generation data from EPA Clean Air Markets for calendar year 2020.
Data current as of 07/11/2021