Monday, July 27, 2015

Response to the San Antonio Express-News July 23rd Headline

EN Headline.jpg

Before I delve into this article, a few thoughts on dirty air, ozone etc.

One of the most frustrating aspects of discussing high ozone days is the fact that high ozone days are 100% controlled by an uncontrollable force called “weather”.  A city like San Antonio, with essentially the same emissions from year to year can have as few as two high ozone days (2014) or as many as over a dozen in other years. Early fall cool fronts with “dirty high pressure” systems that usher in polluted air can change our daily ozone levels from 35 ppb. to 75ppb. in a matter of days.  On the other hand, that same cool front can also have little impact on our ozone if clouds form during the time we are under the “dirty high pressure”, by not allowing UV light to convert NOx into O3 (ozone). These are random events, but yet the EPA penalizes cities for having high ozone days regardless of the weather.  Most people would be very upset if the EPA decided to start fining cities for having too many thunderstorms, but that essentially is what is happening.

“Dirty Air.”

When any of us hears or reads those two words we instantly think of smog, smokestacks and black soot billowing out of tailpipes. Those are anthropogenic (man-made) sources and can lead to negative health issues if they are not controlled.  In San Antonio, we are often faced with other air quality issues that are rarely mentioned in the media or government. Much of our worst air quality days can be blamed on Mexican smoke, Saharan dust and high pollen.  Mexican smoke from agricultural fires in Mexico and Central America negatively impacts our air and causes haze from April-June. Saharan dust causes haze and elevates particulate matter from June-September and high pollen impacts us from December-April. These natural and man-made events send many citizens a year running to nearby doctors and pharmacies for relief and treatments, but are completely beyond our control.

Before I discuss the Express-News article, I want to let it be known that I do not hold any grudge or ill will toward the writer, Scott Huddleston and I hope he will include me as an alternative source in the future. His writing is professional, but unfortunately, it seems as though most of his sources in this article come from the same perspective on this topic. I will never understand how and why individuals interpret information so differently. The information I discuss in my blog is common knowledge to AACOG members, our city leaders, the Sierra Club and the Environmental Defense Fund. Even so, they give the impression that we are still living in the 60’s, when cars fueled with leaded gasoline and four-barrel carburetors were a threat to our health.  Cars are the great "evil demons" in their minds and we should all be walking, biking, riding the bus or taking a train to work. I'm cool with those modes of transportation (I bike about 25 miles a week), but they fail to see the dramatic improvements in our emission reductions and don’t seem to understand that ozone events are rare and caused by unusual weather patterns. As a member of the AACOG Air Advisory Committee, I invite Scott to attend our public meetings in the future so he can listen to a wide range of questions and comments on ozone modelling data from other like-minded members on the committee.

And now my take on the front page article...

On July 23rd, 2015, the San Antonio Express-News published an article with a banner headline reading "AirQuality worse than Houston".

Let’s see…According to documents from the Alamo Area Council of Governments (AACOG) and the EPA, San Antonio and surrounding counties’ nitrogen oxide emissions are around 190 tons per day compared with Houston’s 1000 tons per day.  Maybe I’m wrong, but I think that makes Houston’s air quality about 5 times dirtier (based on emissions per day) than San Antonio’s, despite its lower than usual ozone recordings from 2012-2014.

The first paragraph states “San Antonio registered the second highest readings for ground-level ozone in Texas for the past three years-even worse than Houston.” This statement is based on the 2012-2014 EPA’s fourth highest, three year average of the ozone reported by regulatory CAMS that measure ozone in most large cities in the USA. Using the three year EPA ozone formula from 2012-2014, our highest 8 hour ozone recording from one CAM (near 1604 and I-10) was tied with Houston's C84 at 80ppb. This is the only time in ozone recorded history that a three year average has put one of San Antonio's CAMs in a tie with Houston.

Rating San Antonio as second in air quality, (based on ozone, not emissions), took looking at last year’s fourth highest eight hour average ozone number of 72 ppb. (below the EPA high ozone standard) and comparing it with Houston’s 71 ppb.  A real stretch of data analysis in my mind. What hurt San Antonio’s 2012-2014 average was 2012, when CAMS 58 hit 87 ppb. as its fourth highest eight hour average. CAMS 23, located near John Marshall HS, only recorded 81 ppb. that year.  If you look at the current three year average (2013-2015) you'll see that once again San Antonio is ranked in third place at 74 ppb vs Houston at 76 ppb. San Antonio’s highest eight hour ozone average for this year is 79 ppb. vs 108 ppb. for Houston.

More importantly, is how many high ozone days we have experienced in the past two years using the three regulatory monitors. In 2014 San Antonio experienced only two high ozone days and so far this year we have experienced only two days as well. While the ozone season is far from over, I do not see this as a sense of urgency or looming health hazard. Mobile and point emissions of nitrogen oxide are diminishing every year despite our rapid growth due to current regulations and advance technology being used in our planes, trains and automobiles.

OK…now let’s talk a little bit about the image that was used to illustrate this story. According to the TCEQ (Texas Commission on Environmental Quality), our ozone levels during the afternoon that this image was taken (July 22nd), were 37 ppb., which is considered to be very low. The only pollutant mentioned by TCEQ was Saharan dust, which has been very prevalent this summer and has been responsible for an increase in my asthmatic symptoms. The Navy Aerosol Analysis and Prediction System model (NAAPS) showed a plume of Mexican smoke moving through our area on Wednesday. Mexican smoke from agricultural fires often degrades our air quality from April-June.  So, the “smog” documented by the photo used on the front page of the paper is from a combination of Mexican smoke and Saharan dust, neither of which have anything to do with San Antonio’s emissions. While the photo doesn't actually mention that the smog is from San Antonio, it certainly gives readers the impression that it is, based on the context of the article and the banner headline.

My councilman, Ron Nirenberg made a couple of quotes at the AACOG Air Executive meeting on Weds. that appeared in this article. “San Antonio must act as soon as possible to reduce air pollution” and that “he’s a little frustrated that the city took two years to craft a plan and is now teetering on noncompliance with the federal air quality standards”.

I’m all for improving our air quality, but let’s look at some data first…

The idling program that is mentioned in the article, removes NOx by 150 tons annually. San Antonio produces around 190 tons per day, so that works out to around a half of a ton per day difference.  This will make only a tiny dent in our ozone. At least this program doesn’t cost the average citizen any money to implement. Vehicle emissions testing are another story.  Vehicle emissions testing are costly to every driver, even if they pass or fail, and make almost no difference in the recorded ozone. Over ten years ago, AACOG modeling data showed that implementing emissions testing would only reduce ozone by ½ of 1 ppb. With cleaner engines, the result in 2015 would even be less.

Based on the latest modeling data from AACOG, local mobile sources (cars, trucks, etc.) in 2018 will contribute only 7 ppb. to our ozone design value (which is currently at 74 ppb. on 7-25-15) and point sources (power plants and manufacturing) will contribute 9 ppb. to that value.  The new EPA standard is predicted to drop to at least 65 ppb.  To reach that new standard, San Antonio would have to remove at least 50% of our vehicles and stop generating 50% of our manufacturing and power plant production.  Based on the latest data from AACOG, even if you were to completely shut down San Antonio, we would still see a design value of 52 ppb. due to transported pollution from other cities, counties, states and countries. Even biogenic sources contribute.  As of the date I am writing my blog, Big Bend National Park has a fourth highest ozone recording of 64 ppb. as compared with San Antonio’s 67 ppb.  Based on traveling there in the past, I don’t recall many planes, trains or automobiles out in the park.

If the EPA does drop the standard to 65 ppb. in October, almost every city in the USA with an ozone monitor will quickly go into nonattainment due to background sources that are beyond their control. Scott Huddleston does quote Universal City Mayor John Williams in the article, who agrees that there is no way San Antonio could lower its eight hour ozone average to 65 ppb..

Later, fellow AACOG Air Advisory Committee member and Sierra Club member, Russell Seal, who often sits only a few feet away from me during our meetings is quoted saying, "Rather than worrying about the EPA's proposals, the panel should ask why San Antonio's readings have been slow to improve, and are now higher than Houston's?"

Based on Russell's quote, I'm wondering if we really do attend the same meetings together. Russell receives the same lengthy model updates, current emissions inventories and ozone updates from AACOG as I do, and yet asks that question?

What our leaders fail to understand is that cities like San Antonio are already reducing our emissions every year.  By 2018, auto emissions will be almost twice as clean as today’s vehicles and that’s only three years away.  Yes, we can always do more, but given that we are a city of over a million people and living in the far south of the United States where ozone season lasts much longer than northern states, I think we are doing a great job of keeping our air clean. What keeps us looming on the edge of nonattainment is not dirtier air, but a continuing changing of the rules.



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