YSM Issue 97.1

FOCUS
Environmental Engineering
IMAGE COURTESY OF FLICKR
The Keystone Pipeline System transports crude oil from the Athabasca oil sands in Alberta, Canada, to various destinations
in the United States.
percentage difference between estimated
carbon emissions and reported values (6,324
percent), while Canadian Natural Resources
had the lowest difference (1,922 percent).
“The benefit of a total gas-phase organic
carbon measurement is that you convert
all of the complex mixture of organic
carbon compounds to carbon dioxide with
a catalyst and just measure the produced
carbon dioxide,” Gentner said. This means
that instead of individually quantifying
each organic carbon compound present
in the atmosphere, the researchers were
able to directly measure carbon content,
streamlining the measurement process.
Consequently, IVOCs and SVOCs are just
as much a part of the equation as VOCs
normally are. However, this conversion
makes it difficult to attribute respective
measurements to the specific organic
carbon compounds. Thus, additional
measurements were necessary to conduct
the experiments and distinguish between
different organic compounds. In addition,
based on observations from the aircraft,
the researchers determined that non-
combustion-related sources largely
contribute to the emissions. “[This] is likely
contributed to by a range of on-site sources
across the lifecycle of oil sands extraction
[and] processing,” He said.
Supplementary experiments were
conducted to determine whether mature
fine tailings also contributed to the total
organic carbon observed during the flights.
Mature fine tailings are structures that
are built into the earth and house mining
waste from oil sands. This waste consists
of a mixture of particles, such as sand, clay,
and silt, which are difficult to separate
from wastewater and serve as a persistent
environmental pollutant. Over time, off-
gassing emissions—emissions released
under normal environmental conditions—
were measured. The magnitude and chemical
composition of emissions were determined,
and the researchers demonstrated that
mature fine tailings contribute to the total
organic carbon observed.
“The collection of aircraft and laboratory
measurements in the study demonstrates
the importance of considering life-cycle-
wide emissions, spanning from mining
through waste management and disposal,”
Gentner said.
Limitations of Aircraft-Based Emissions
Monitoring
These new aircraft-based measurements
elucidated stark differences between the total
reported annual carbon emissions compared
to the total annual carbon emission estimates,
calling for a need to better monitor the impact
of oil production on our climate. However,
there are a few limitations to this study.
Methane is responsible for approximately
ABOUT THE AUTHOR
sixteen percent of global emissions, making
it the second-largest contributor to climate
warming after carbon dioxide. Despite being
one of the most abundant greenhouse gases, it
was excluded from the study. “Other research
by Environment and Climate Change
Canada has specifically examined methane
[and carbon dioxide] emissions,” He said.
Thus, the researchers decided to specifically
focus on VOCs, IVOCs, and SVOCs, which
methane does not fall under.
In addition, it may be difficult to use
aircraft-based measurements in other cases
beyond Canada’s oil sands due to sensitivity.
“Generally speaking, aircraft-based
measurements are challenging since you have
an array of sensitive instrumentation on the
aircraft that you are preparing for each flight,”
Gentner said. The researchers were careful to
adequately calibrate and monitor each flight
to prevent any inaccurate measurements.
Improving Reporting of Total Organic
Carbon Emissions
Ultimately, the findings from this
study can help inform future policy. The
researchers identified challenges with
reporting and monitoring diverse gaseous
organic compounds but also highlighted
the necessity of obtaining comprehensive
emissions data. With these new methods
for quantifying total carbon emissions
beyond VOCs, policymakers will be able
to determine which programs must be
implemented. As we seek to mitigate
worsening climate change, it is imperative to
have accurate measurements of total carbon
emissions to create accurate, effective,
and crucial environmental policies and
regulations across the globe. ■
ABIGAIL JOLTEUS
ABIGAIL JOLTEUS is a junior in Berkeley College from Toronto, Canada, and West Palm Beach, Florida.
Outside of YSM, she conducts research in the Konnikova Lab. She enjoys poeticizing the mundane, the
smell of books, and the sound of rain. She also loves canoeing, swimming, and gardening.
THE AUTHOR WOULD LIKE TO THANK Megan He, Lexie Gardner, and Drew Gentner for their time,
dedicaton, and expertise.
FURTHER READING:
Liggio, J., Li, S. M., Hayden, K., Taha, Y. M., Stroud, C., Darlington, A., Drollette, B. D., Gordon, M., Lee, P.,
Liu, P., Leithead, A., Moussa, S. G., Wang, D., O'Brien, J., Mittermeier, R. L., Brook, J. R., Lu, G., Staebler, R.
M., Han, Y.,…Gentner, D. R. (2016). Oil sands operations as a large source of secondary organic aerosols.
Nature, 534(7605), 91–94. https://doi.org/10.1038/nature17646
Rios, B., Díaz-Esteban, Y., & Raga, G. B. (2023). Smoke emissions from biomass burning in Central Mexico
and their impact on air quality in Mexico City: May 2019 case study. Science of the Total Environment, 904,
166912. https://doi.org/10.1016/j.scitotenv.2023.16691
18 Yale Scientific Magazine March 2024 www.yalescientific.org