Article
Environmental Sciences
Samuel Rossabi, Jacques Hueber, Wei Wang, Pam Milmoe, Detlev Helmig
Summary: The study monitored methane and nonmethane volatile organic compounds near Boulder in the Northern Colorado Front Range to investigate their spatial distribution and sources, with a focus on the impact of oil and gas operations on regional air quality. Findings showed that light alkane petroleum hydrocarbons were the dominant VOCs analyzed, while longer-lived VOCs like ethane and propane decreased with increasing elevation. This study also revealed elevated levels of VOCs at mountain sites due to upslope transport of plumes from the plains, and increasing VOC concentrations closer to oil and gas development sites in suburban East Boulder County.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2021)
Article
Astronomy & Astrophysics
Patrick J. Reddy
Summary: The Denver Metro/Northern Front Range area is severely nonattainment for O-3. Previous research indicates north-south gradients in oil and gas (O&G) impacts on O-3, with greater contributions in the north. Recent analysis shows reductions in methane and ethane emissions in the area from 2013 to 2020, consistent with reductions in O&G volatile organic compound (VOC) emissions. The gradient in trends suggests significant O&G emissions reductions have benefited locations in the central and northern portions of the nonattainment area (NAA).
EARTH AND SPACE SCIENCE
(2023)
Article
Environmental Sciences
Congmeng Lyu, Shannon L. Capps, Kent Kurashima, Daven K. Henze, Gordon Pierce, Amir Hakami, Shunliu Zhao, Jaroslav Resler, Gregory R. Carmichael, Adrian Sandu, Armistead G. Russell, Tianfeng Chai, Jana Milford
Summary: Recent expansion of oil and natural gas production activities in the Denver-Julesburg Basin have led to significant increase in nonmethane hydrocarbon (NMHC) emissions, contributing to ground-level ozone formation. Using different methods, it was estimated that O&NG activities in Platteville and Denver have different contributions to NMHC mixing ratios. Vehicle emissions in Denver have a larger impact on NMHC levels compared to O&NG activities.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Environmental Sciences
James L. Crooks, Rachel Licker, Adrienne L. Hollis, Brenda Ekwurzel
Summary: The study found that the ozone climate penalty in the Denver Metro North Front Range region is most pronounced around major urban centers and is positively associated with factors such as the percentage of Hispanic/Latino residents and children living within 100-200% of the federal poverty level.
JOURNAL OF EXPOSURE SCIENCE AND ENVIRONMENTAL EPIDEMIOLOGY
(2022)
Article
Environmental Sciences
Subin Yoon, Stephanie M. Ortiz, Adelaide E. Clark, Tate E. Barrett, Sascha Usenko, Rachelle M. Duvall, Lea Hildebrandt Ruiz, Jeffrey K. Bean, Cameron B. Faxon, James H. Flynn, Barry L. Lefer, Yu Jun Leong, Robert J. Griffin, Rebecca J. Sheesley
Summary: Understanding the sources and composition of organic carbon in the Houston metropolitan area and the relationship with O-3 and PM concentrations was investigated using chemical mass balance modeling and radiocarbon analysis. Results showed a consistent urban background of contemporary carbon and motor vehicle exhaust, with fossil SOC having a stronger correlation with daily maximum 8 h average O-3 during high PM and O-3 events. Impacts of point source emissions processed by onand off-shore wind cycles likely contribute to peak events for both PM and O-3 in the greater Houston metropolitan area.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Engineering, Environmental
Pamela S. Rickly, Matthew M. Coggon, Kenneth C. Aikin, Raul J. Alvarez II, Sunil Baidar, Jessica B. Gilman, Georgios I. Gkatzelis, Colin Harkins, Jian He, Aaron Lamplugh, Andrew O. Langford, Brian C. McDonald, Jeff Peischl, Michael A. Robinson, Andrew W. Rollins, Rebecca H. Schwantes, Christoph J. Senff, Carsten Warneke, Steven S. Brown
Summary: Increasing trends in biomass burning emissions significantly impact air quality in North America. The transport of smoke from local and long-range fires has been found to increase the mixing ratios of ozone (O3) in urban areas. This is primarily due to the transport of pyrogenic volatile organic compounds (PVOCs) and the influence of O3 produced within the smoke. Detailed chemical measurements have shown that both local and long-range smoke periods lead to increases in carbon monoxide, background O3, OH reactivity, and total VOCs, while the NOx mixing ratios remain constant. Box-model calculations indicate that local O3 production is in the NOx-sensitive regime, with PVOCs substantially increasing O3 production in the transition and NOx-saturated regimes.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Environmental Sciences
Lisa S. Darby, Christoph J. Senff, Raul J. I. I. I. I. Alvarez, Robert M. Banta, Laura Bianco, Detlev Helmig, Allen B. White
Summary: The study conducted in the vicinity of Denver in the summer of 2008 revealed the transport of pollution into wilderness areas of the Rocky Mountains. Findings demonstrated that under specific conditions, ozone-enriched air can be advected into high-elevation mountain sites, highlighting a potentially important ozone transport mechanism in mountainous terrain.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2021)
Article
Geosciences, Multidisciplinary
Wolfgang Steinbrecht, Dagmar Kubistin, Christian Plass-Duelmer, Jonathan Davies, David W. Tarasick, Peter von der Gathen, Holger Deckelmann, Nis Jepsen, Rigel Kivi, Norrie Lyall, Matthias Palm, Justus Notholt, Bogumil Kois, Peter Oelsner, Marc Allaart, Ankie Piters, Michael Gill, Roeland Van Malderen, Andy W. Delcloo, Ralf Sussmann, Emmanuel Mahieu, Christian Servais, Gonzague Romanens, Rene Stubi, Gerard Ancellet, Sophie Godin-Beekmann, Shoma Yamanouchi, Kimberly Strong, Bryan Johnson, Patrick Cullis, Irina Petropavlovskikh, James W. Hannigan, Jose-Luis Hernandez, Ana Diaz Rodriguez, Tatsumi Nakano, Fernando Chouza, Thierry Leblanc, Carlos Torres, Omaira Garcia, Amelie N. Rohling, Matthias Schneider, Thomas Blumenstock, Matt Tully, Clare Paton-Walsh, Nicholas Jones, Richard Querel, Susan Strahan, Ryan M. Stauffer, Anne M. Thompson, Antje Inness, Richard Engelen, Kai-Lan Chang, Owen R. Cooper
Summary: Throughout spring and summer 2020, ozone levels in the northern extratropics were unusually low in the free troposphere. The observed anomaly was primarily attributed to emissions reductions caused by the COVID-19 crisis.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Samuel J. Oltmans, Lucy C. Cheadle, Detlev Helmig, Helene Angot, Gabrielle Petron, Stephen A. Montzka, Edward J. Dlugokencky, Benjamin Miller, Bradley Hall, Russell C. Schnell, Jonathan Kofler, Sonja Wolter, Molly Crotwell, Carolina Siso, Pieter Tans, Arlyn Andrews
Summary: Research conducted in the Colorado Denver-Julesburg Basin (DJB) from 2008 to mid-2016 using air samples collected at the Boulder Atmospheric Observatory (BAO) found that emissions from oil and natural gas (O&NG) have remained relatively constant, despite significant production increases. Elevated mole fractions of O&NG tracers such as methane and propane were observed in air transported from the northeast sector, while emissions from the south (urban) sector showed lower concentrations. These results contrast with projections from VOC emissions inventory, indicating a discrepancy between actual emissions and predicted reductions.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2021)
Article
Engineering, Civil
Isaac S. Bukoski, Sheila F. Murphy, Andrew L. Birch, Holly R. Barnard
Summary: By analyzing water samples from small foothill catchments and a larger catchment extending from foothills to subalpine regions, this study investigated the impact of land use and precipitation changes on hydrologic flowpaths. Findings showed that lithogenic constituents increased and dissolved organic carbon decreased with decreasing seasonal runoff, indicating a transition in flowpaths, and suggested that anthropogenic activities can influence local stream and groundwater chemistry. Additionally, the study highlighted the influence of anthropogenic land use on runoff generation during storm events.
JOURNAL OF HYDROLOGY
(2021)
Article
Geosciences, Multidisciplinary
Clara Betancourt, Timo Stomberg, Ribana Roscher, Martin G. Schultz, Scarlet Stadtler
Summary: The AQ-Bench dataset contributes to shared data usage and machine learning methods in environmental science by enabling researchers to relate global air quality metrics with metadata and explore different machine learning techniques for air quality estimation. The dataset includes aggregated air quality data and metadata from over 5500 monitoring stations worldwide, focusing on tropospheric ozone metrics and offering a baseline for linear regression, neural network, and random forest methods. AQ-Bench serves as a blueprint for environmental benchmark datasets and exemplifies data reuse according to the FAIR principles.
EARTH SYSTEM SCIENCE DATA
(2021)
Article
Environmental Sciences
Matthew S. Johnson, Kevin Strawbridge, K. Emma Knowland, Christoph Keller, Michael Travis
Summary: In the summer of 2019, Siberian wildfires significantly impacted air quality and composition in western Canada through trans-Pacific and trans-Arctic transport pathways. Observations and simulations indicated that the effects were mainly seen in the free troposphere.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Environmental Sciences
Jianfeng Li, Yuhang Wang, Ruixiong Zhang, Charles Smeltzer, Andrew Weinheimer, Jay Herman, K. Folkert Boersma, Edward A. Celarier, Russell W. Long, James J. Szykman, Ruben Delgado, Anne M. Thompson, Travis N. Knepp, Lok N. Lamsal, Scott J. Janz, Matthew G. Kowalewski, Xiong Liu, Caroline R. Nowlan
Summary: Nitrogen oxides play a crucial role in the formation of ozone and aerosols, impacting human health, global radiation budget, and climate. Observations and model simulations help understand the diurnal and spatial variations of NO2. Discrepancies between observations and simulations require further investigation and adjustment.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Engineering, Environmental
Ilana B. Pollack, Megan E. McCabe, Dana R. Caulton, Emily Fischer
Summary: Quantifying the enhancement ratios of ammonia (NH3) to methane (CH4) from agricultural sources is crucial for understanding air pollution and nitrogen deposition. A study conducted in northeastern Colorado Front Range reveals that concentrated animal feeding operations (CAFOs) in the region emit significant amounts of NH3 and CH4, which is further complicated by the presence of oil and natural gas extraction activities. Utilizing measurements from a research aircraft, the study demonstrates that NH3 and ethane (C2H6) can be used together to distinguish between near-source enhancements of CH4 from agriculture and oil and gas activities.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Forestry
Ariel B. Demarest, Paula J. Fornwalt, Brett H. Wolk, Kyle C. Rodman, Miranda D. Redmond
Summary: Mechanical restoration treatments in dry conifer forests of the Colorado Front Range have been found to significantly increase native understory plant cover and richness, while limiting invasion from non-native species. The cover and richness of native plants in treated areas were associated with 19th-century forest structural conditions and were better predicted by spring moisture availability rather than long-term water deficit. These findings highlight the importance of ongoing restoration activities in dry conifer forests.
FOREST ECOLOGY AND MANAGEMENT
(2023)
Editorial Material
Meteorology & Atmospheric Sciences
Michael P. Jensen, James H. Flynn, Laura M. Judd, Pavlos Kollias, Chongai Kuang, Greg Mcfarquhar, Raj Nadkarni, Heath Powers, John Sullivan
BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY
(2022)
Article
Environmental Sciences
Zhifeng Yang, Belay Demoz, Ruben Delgado, Andrew Tangborn, Pius Lee, John T. Sullivan
Summary: This study investigates the influence of the Chesapeake Bay on local ozone concentration using a weather forecasting model. The model overestimates surface ozone and the bay breeze circulation contributes to ozone concentration. The differences in boundary layer depth and bay width also affect ozone concentration.
Article
Meteorology & Atmospheric Sciences
S. -Y. Ogino, K. Miyazaki, M. Fujiwara, M. I. Nodzu, M. Shiotani, F. Hasebe, J. Matsumoto, J. Witte, A. M. Thompson, H. A. Nguyen-Thi, T. V. Nguyen
Summary: The study indicates that the enhancement of lower tropospheric ozone concentration in Hanoi during spring is mainly influenced by precursor emissions from biomass burning in the inland Indochina Peninsula. Polluted air mainly originates from the western region of Hanoi, while clean air mainly comes from the eastern oceanic area.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Engineering, Environmental
Madankui Tao, Arlene M. Fiore, Xiaomeng Jin, Luke D. Schiferl, Roisin Commane, Laura M. Judd, Scott Janz, John T. Sullivan, Paul J. Miller, Alexandra Karambelas, Sharon Davis, Maria Tzortziou, Lukas Valin, Andrew Whitehill, Kevin Civerolo, Yuhong Tian
Summary: Understanding the spatial and temporal variability of ozone formation on a local scale is crucial for effective mitigation. By combining airborne remote sensing data and ground-based measurements, this study investigates changes in ozone precursors and the inferred chemical production regime on high-ozone days in two Northeast urban domains. The results show that the ratio of HCHO-VCDTrop to NO2-VCDTrop generally increases on ozone exceedance days, indicating a transition towards a more NOx-sensitive ozone production regime. Warmer temperatures and local emissions play a role in the high-ozone days, with slower wind speeds in one domain and stronger, southwesterly winds in the other.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Joel Dreessen, Xinrong Ren, Daniel Gardner, Katherine Green, Phillip Stratton, John T. Sullivan, Ruben Delgado, Russ R. Dickerson, Michael Woodman, Tim Berkoff, Guillaume Gronoff, Allison Ring
Summary: The OWLETS-2 study found that the concentrations of TNMHC and VOCs on an island site in the northern Chesapeake Bay were 2.1 and 3.4 times higher, respectively, than those at a nearby land site. The chemical differences between the island and land sites were observed both in the air above the water and on the water surface. The VOC and photochemistry patterns at the island site were mainly driven by marine sources, indicating the need for separate ozone abatement strategies for water and land.
JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION
(2023)
Article
Astronomy & Astrophysics
Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, David W. Tarasick, Roeland Van Malderen, Herman G. J. Smit, Holger Voemel, Gary A. Morris, Bryan J. Johnson, Patrick D. Cullis, Rene Stuebi, Jonathan Davies, Michael M. Yan
Summary: This paper examines the stability and accuracy of global ozonesonde network data since 2004. It finds that the data is stable and reliable, with comparisons to satellite measurements showing consistent results within a small margin of error. However, there is a dropoff in ozone measurements at select stations in the tropics and subtropics, which needs further investigation. Overall, ozonesonde data are of high quality and stability, making them valuable for various studies and research.
EARTH AND SPACE SCIENCE
(2022)
Article
Environmental Sciences
John T. Sullivan, Ryan M. Stauffer, Anne M. Thompson, Maria A. Tzortziou, Christopher P. Loughner, Carolyn E. Jordan, Joseph A. Santanello
Summary: Coastal areas are densely populated and economically important regions. Protecting the health of humans and ecosystems in these areas and understanding the impacts of environmental stressors like air pollution is crucial.
Article
Meteorology & Atmospheric Sciences
Michael A. A. Todt, Elizabeth Asher, Emrys Hall, Patrick Cullis, Allen Jordan, Kensy Xiong, Dale F. F. Hurst, Troy Thornberry
Summary: Stratospheric aerosol is important for Earth's radiative balance, and systematic measurements are needed to understand its properties and improve global models. The B(2)SAP project uses lightweight payloads on meteorological balloons to measure aerosol properties and meteorological data from the surface to the middle stratosphere. These measurements provide a new record of in situ observations and help validate satellite-based estimates.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Astronomy & Astrophysics
Anne M. Thompson, Debra E. Kollonige, Ryan M. Stauffer, Alexander E. Kotsakis, Nader Abuhassan, Lok N. Lamsal, Robert J. Swap, Donald R. Blake, Amy Townsend-Small, Holli D. Wecht
Summary: The Satellite Coastal and Oceanic Atmospheric Pollution Experiment (SCOAPE) cruise in the Gulf of Mexico was conducted to determine the feasibility of using satellite data to measure air quality in ONG operations. The findings showed that satellite NO2 data can be used to monitor ONG activity, but there are limitations in coastal regions.
EARTH AND SPACE SCIENCE
(2023)
Article
Environmental Sciences
Maurice Roots, John T. Sullivan, Ruben Delgado, Laurence Twigg, Belay Demoz
Summary: This study discusses the use of multiple observation platforms as an integrated monitoring system to characterize and analyze ozone exceedance events in the mid-Atlantic region of the United States. By observing vertically resolved ozone, atmospheric backscatter, winds, as well as surface ozone observations, aerosol optical depth, and air mass transport simulations, the spatiotemporal characteristics and impact mechanisms of the exceedance events were revealed.
ATMOSPHERIC ENVIRONMENT
(2023)
Article
Meteorology & Atmospheric Sciences
Nikolay V. Balashov, Lesley E. Ott, Brad Weir, Sourish Basu, Kenneth J. Davis, Natasha L. Miles, Anne M. Thompson, Ryan M. Stauffer
Summary: This study examines the effects of the 2019 floods in the Midwestern and Southern US on the ability of land ecosystems to absorb CO2. The results show that floods have complex effects on the carbon cycle in different regions, highlighting the need for further research to understand how land ecosystems will respond to climate change.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Meteorology & Atmospheric Sciences
Matthew S. S. Johnson, Amir H. H. Souri, Sajeev Philip, Rajesh Kumar, Aaron Naeger, Jeffrey Geddes, Laura Judd, Scott Janz, Heesung Chong, John Sullivan
Summary: Satellite retrievals of formaldehyde (HCHO) and nitrogen dioxide (NO2) from two satellite sensors (OMI and TROPOMI) were compared to investigate the sensitivity of ozone (O3) production to emissions of nitrogen oxides and volatile organic carbon compounds. The study found that OMI and TROPOMI had high biases in clean environments and more accurate comparisons in moderately polluted to polluted regions. The retrievals of NO2 had similar systematic biases, while the HCHO retrievals differed more, with TROPOMI having lower uncertainty.
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2023)
Article
Meteorology & Atmospheric Sciences
Nora Mettig, Mark Weber, Alexei Rozanov, John P. Burrows, Pepijn Veefkind, Anne M. Thompson, Ryan M. Stauffer, Thierry Leblanc, Gerard Ancellet, Michael J. Newchurch, Shi Kuang, Rigel Kivi, Matthew B. Tully, Roeland Van Malderen, Ankie Piters, Bogumil Kois, Rene Stubi, Pavla Skrivankova
Summary: Vertical ozone profiles were retrieved by combining spectral measurements from ultraviolet and infrared range, using data from TROPOMI/S5P and CrIS/SuomiNPP satellites. The combined retrieval method improves the vertical resolution and extent of ozone profiles compared to single wavelength retrievals. It also enhances the accuracy of tropospheric ozone and to a lesser degree stratospheric ozone.
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2022)
Article
Environmental Sciences
Nikos Daskalakis, Laura Gallardo, Maria Kanakidou, Johann Rasmus Nuess, Camilo Menares, Roberto Rondanelli, Anne M. Thompson, Mihalis Vrekoussis
Summary: This study investigates the spatiotemporal variability of ozone mixing ratio in the pristine South Pacific Ocean using 21-year-long ozone records. The findings reveal that even the most pristine oceanic region is influenced by distant biomass burning emissions, with significant impacts on CO and ozone levels in the area.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)