Today, my favorite Air Geek made an observation and shared it with me.
The wind is out of the north according to Weather Underground, albeit at 1mph or so. Usually this means the southern tire of monitors – Redbird, Arlington, Midlothian – start to creep up. But tha’s not what’s happening. Instead monitors in Grapevine, Keller and Mecham Field in FW are all over 85. These are usually the monitors that go up when the wind is out of the S-SE, carrying coal, kiln and central city emissions into the NW corner of Tarrant County. That they would trip when the wind is coming from the opposite direction is unusual.
Now, look on a map and tell me what sources are north of the tripping monitors. I don’t think it’s traffic in Denton or Decatur.
If only I had made a screen print of the maps (the maps update so it won’t be the same map from earlier) from right after lunch you would see that the orange sites were in Tarrant County. The north wind was blowing some of that VOC laden air from Decatur and Denton. It’s certainly not the Decatur traffic causing all that bad air.
From EDF’s analysis:
- The oil and gas industry releases about 42 tons of ozone forming VOC emissions per day in Wise County.
- The oil and gas industry releases about 37 tons of ozone forming VOC emissions per day in Denton County.
- 100 tons of VOC emissions are produced daily from all of the cars and trucks in the nine-county DFW ozone non-attainment area.
Here’s a screen capture of the Grapevine monitor.