- Texas showed a 32% decrease in ozone, the 6th largest decrease in the United States.
- All other states (excluding Texas) averaged a decrease of only 17%.
- 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.
- Numbers are based on the three-year average of the fourth-highest eight-hour ozone concentration from all monitors operating within each state.
- Texas has two of the most populous combined statistical areas (CBSAs) in the US.
- Of those five areas, the two areas in Texas, the Houston-Galveston-Brazoria area and the Dallas-Fort Worth area, have the first and tied for the second largest decrease in ozone design values from 2000 through 2018, 30% and 25% respectively.
- Of the five largest CBSAs, the DFW area has the lowest eight-hour ozone design value in 2018 and the HGB area has the second lowest eight-hour ozone design value in 2018.
- A comparison of fourth-highest eight-hour ozone concentrations for the Houston and Los Angeles CSA’s reveals a downward linear trend for both Houston and Los Angeles.
- However, the fourth-highest ozone in Houston is decreasing at a faster rate of 25% compared to California, which has only seen a 9% decrease from 2000 through 2018.
- In 2018, the fourth-highest ozone value was 23 ppb higher in Los Angeles than in Houston.
- The air quality index (AQI) takes into account all criteria pollutants.
- Houston has many more good (green) days when compared to Los Angeles. Further, the number of good days has increased by 239% from 2000 through 2018 in Houston while the number of good days has increased by only 30% over that same time in Los Angeles.
- In addition, Houston’s air quality in 2018 was either good (green) or moderate (yellow) 90% of the time while Los Angeles only had good or moderate air quality 70% of the time.
- Of the 20 states with the highest fossil-fuel fired power plant NOX emissions, Texas ranks 7th 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 2018.
- Data current as of 2/5/2019
- Of the 20 states with the highest fossil-fuel fired power plant SO2 emissions, Texas ranks 9th lowest in emissions per capita.
- Though Texas has the 2nd highest population among all states, emissions per person are low, even in comparison to such industrial states as Indiana, Ohio, and Pennsylvania.
- Emissions and generation data from EPA Clean Air Markets for calendar year 2018.
- Data current as of 2/5/2019
by the US EPA
