Big Bend Conservancy
Most of The Bends pollution comes from Mexico and the west coast I believe. Sent from flat land
Quote from: Txlj on October 12, 2017, 04:34:26 AMMost of The Bends pollution comes from Mexico and the west coast I believe. Sent from flat landNot really, I remember some past studies that surprised folks that most came from the US. Here is the TEQ page with past trajectories showing where the air came from that last 48 hrs.
Quote from: mule ears on October 12, 2017, 07:23:15 AMQuote from: Txlj on October 12, 2017, 04:34:26 AMMost of The Bends pollution comes from Mexico and the west coast I believe. Sent from flat landNot really, I remember some past studies that surprised folks that most came from the US. Here is the TEQ page with past trajectories showing where the air came from that last 48 hrs.FROM THE BRAVO REPORT (Big Bend Regional Aerosol and Visibility Observational (BRAVO) )The BRAVO study involved a four month intensive monitoring period from July through October 1999, followed by a four-year dataanalysis and modeling effort examining the BRAVO data and past data collected at Big Bend NP. On average, during the BRAVO period (1999 study) U.S. sources were responsible for about 55% ofBig Bend’s particulate sulfate, with the eastern U.S. responsible for about 30% andeastern Texas contributing about 17%.Mexican sources, including the Carbón power plant, were responsible for about 38% ofBig Bend’s particulate sulfate.At 20%, the Carbón power plant in Mexico is the single largest point source contributorto Big Bend’s sulfate haze during the BRAVO study period.At any given time during the BRAVO study, over half of the sulfate haze can come fromeastern U.S., eastern Texas, or Mexican sources.On the clear days Mexico and the western U.S. were the largest contributors during theBRAVO study. Throughout the year airmasses en route to Big Bend frequently reside over Mexico, inparticular northern Mexico. Airflow from eastern Texas and the eastern U.S. is most frequent during late summer andfall months during the period with the greatest contribution to haze by particulate sulfatecompounds. Airflow from the western U.S. to Big Bend is greatest in the winter months when hazelevels at the park are lowest.The highest sulfate haze periods during BRAVO were associated with low-speed andlow-level transport from the eastern U.S., eastern Texas, and northeastern Mexico. The lowest sulfate haze periods during BRAVO were associated with higher-speedtransport from the Gulf of Mexico along the Mexican/Texas border to Big Bend, from thenorth, and from the western U.S.
Haziness comes and goes naturally and has for millenia. That coal burning might contribute to it is not proven.
There is no simple answer to the question of what sources are responsible for the sulfate haze at Big Bend NP; sources in both the United States and Mexico are responsible. Mexican SO2 emissions contribute to the sulfate haze more frequently, but to generate the highest sulfate and haze events that occur in the late summer and fall, contributions from Texas and the Eastern United States must also occur. The largest individual contributor to the sulfate at Big Bend during BRAVO was the Carbon facilities in Northern Mexico. Substantial changes in emissions from those facilities would reduce sulfate levels at Big Bend and likely result in small but noticeable changes in haze on many days; however, this would only make a small difference to the worst haze episodes during late summer and early fall. To substantially affect all of the sulfate and haze episodes during the late summer and fall when U.S. contributions to Big Bend are large would require SO2 emission changes in both Texas and the Eastern United States. Although the Eastern United States contributed nearly twice as much sulfate to Big Bend compared with Texas, Eastern U.S. emissions are ~14 times larger than those in Texas. Therefore, larger absolute emissionreduction would be required from the Eastern United States compared with Texas for commensurate reductions in sulfate.
Cue the anthropogenic climate change deniers in 3...2...1...
Catz, I'm sorry if I missed any intended sarcasm in your first post. Either way, thanks for the chance to rant.Cue the anthropogenic climate change deniers in 3...2...1...
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