As has been well documented, free radical production in the
troposphere through either primary or secondary pollutants leads to rather
deleterious effects. Through the release of various pollutants, photochemical
smog is given an opportunity to form and thus can cause adverse health and
environmental effects. This effect, however, is usually catalyzed under ideal
conditions: warmth, sunlight and relatively little movement of air mass in
order to keep the reactants in the area. An interesting phenomena, however, has recently been exposed
in Northeastern Utah, a main gas and oil basin.
The
Unitah Basin in Northeastern Utah is home to numerous oil and gas wells, boasting
a relatively small population of 50,000. This location is unique, however, as
it exceeded the national air quality standard 49 times in 2013, according to a
recent article published in Science Daily by Edwards et. al. Though this may
not sound too farfetched for an oil basin, this excess ozone production peaked
during the winter months, when seemingly none of the required conditions are
met. Due to the oil basin, there are high amounts of VOCs emitted into the
surrounding air that become concentrated due to an inversion of air
temperature. Snow cover increases the surface albedo, or reflection
coefficient, and provides more sunlight to catalyze the reaction, producing
ozone as a secondary pollutant through reactions with products of VOC
dissociation: carbonyls. James Roberts, of the NOAA ESRL, explains the
importance of these wintery conditions, stating, "Oil and gas emissions of
VOCs were high in all three years, but high ozone occurred only in the cold,
snowy stagnant periods.”
The
publication released by Nature furthered this claim, as the authors explained
the significance of the produced carbonyl products coupled with the lack of
primary hydroxyl production due to the lack of water vapor and UV light. Due to
the high presence of VOC emission from the gas and oil basin (which attribute
to 92% of its production), there is a great potential for ozone production.
Since these emissions are released into a shallow, stable boundary layer
coupled with a higher reflection coefficient, the photolytic reaction of VOC is
allowed to occur. These oxygenated VOC products, namely carbonyls, can then
amplify the response of the relatively few primary radicals produced in the
troposphere (due to insufficient conditions) resulting in efficient ozone
production.
Overall,
I believe that the article in Science Daily did a fairly good job of summing up
the findings of the Nature article. While it succinctly conveyed the main point
of the article, however, it did leave out exactly how or why the presence of
snow accelerates the production of ozone. Also, I think some of the language
used makes the article seem less precise, namely when talking about VOCs and
nitric oxides “cooking up” into the pollutants. The article in general gives
the lay public a better understanding of the production of ozone and hints at
the adverse health effects, but leaves out some key points; I would give it a
7/10.
ScienceDaily article: http://www.sciencedaily.com/releases/2014/10/141001133016.htm
I liked how the article compared the Uintah Basin's ozone levels to Riverside, CA's ozone levels. Definitely shows how much of an impact VOCs can have on higher wintertime ozone levels.
ReplyDeleteI would also be curious to see how ozone levels in an urban area on the east coast would look like. This may even be different from that of Riverside because sulfur compounds are more prominent on the east coast whereas NOx compounds are more prominent on the west coast.
I found both articles really interesting and very factual. I never took into account that high amount of ozone could be produced in the winter months, I thought mainly in the summer months. However, Nature described the process of surface albedo in which the sun shines on the snow then reflects back into the sky decreasing the ozone. I have previously heard of this concept with glaciers and snow cover, but never thought it could happen in latitudes south of the Arctic or north of Antarctica. I found it funny that every time Science Daily brought up chemical processes and reactions they referred to it as “sparking up.” They did not explain any of the chemical processes, however, they did refer to VOCs which helps introduce the public to a scientific term. I cannot believe that Utah exceeded the National Air Standard 49 times in 2013. Science Daily stated that these air conditions limit locals outside time, thus I would not like to live in this area. What’s amazing about this article is that it puts into perspective that not only can New York City and Los Angeles release vast amount of pollutants but so can rural areas used for gas extraction. I wonder how humans will intervene with this process, possibly by trapping the harmful chemicals released or invest in winter snow removal in this area?
ReplyDeleteStefanie's comment about snow removal makes me wonder how much area of snow coverage is required. With the possibility of increasingly severe winters, I wonder if this is a phenomenon that we could see in other areas of the country as well, maybe even in more urban areas.
ReplyDeleteI am curious to know whether or not Michigan has any similar issues with ozone in winter months due to it's growing interest in natural gas drilling. Are "Michigan" weather patterns also seem to provide a prime opportunity for temperature inversions that can facilitate this process. Then again, we do live closer to the east coast where we have more sulfates in the air, so this may not be as much of a concern. Great Article, Matt!
ReplyDeleteSort of stemming off of Daniel's comment, I also think it would be interesting to find out if Michigan or other states with similar topological and industrial areas (and of course similar seasonal patterns) have experienced something like this phenomenon. The mechanisms that drive this process certainly make sense especially based on what we've learned. If this area is exceeding the air quality standard throughout the year, I wonder if this phenomenon can be mitigated by falling within (or well below) national air quality standards especially in the months leading to Winter.
ReplyDelete