Congrats to Dr. Crystal McClure, newest PhD graduate in the Jaffe Group

Best wishes to Crystal McClure for the successful defense of her PhD dissertation on May 7, 2018! Her dissertation—titled Impacts of Biomass Burning on Ozone, Particulate Matter, and Carbon Dioxide in the Northwest U.S.—capped 7 years of solid work in the Jaffe Group.

Dan Jaffe and Crystal McClure celebrate her PhD defense

Crystal is the first author on 2 published papers, 1 recently accepted paper, and 1 paper currently in review. (See her papers on the Publications page.) Later this summer, she will begin a post-doctoral fellowship at UC Davis with Chris Cappa that focuses on the optical properties of black carbon from wildfires.

Crystal offered some sage advice for students, and all of us: “Setbacks are part of the journey. Learn to embrace them and you’ll find that you learn and benefit more from your failures than your successes.” We are so excited for you, Crystal, and will miss you!

2018 begins with 3 new group papers

The Jaffe Group has kicked off 2018 with 3 new publications.

Xi Gong, et al., Ozone in China: Spatial distribution and leading meteorological factors controlling O₃ in 16 Chinese cities. Gong and her coauthors examined ozone (O₃) concentrations in 16 Chinese cities and developed a statistical model to estimate the maximum daily 8-hour (MDA8) O₃ during 2014–2016. They found that the Generalized Additive Model (GAM) captured 43-90% of daily O₃ variations. They also identified the leading meteorological factors that affect O₃ for each city. Read the full paper here.

Average 8-hour MDA8 (ug/m3) ozone concentrations for 16 Chinese cities, 2014-2016 — Average maximum daily 8-hour (MDA8, ug/m³) ozone concentrations for 16 Chinese cities, 2014-2016.

Pao Baylon, et al., Impact of biomass burning plumes on photolysis rates and ozone formation at the Mount Bachelor Observatory. Baylon and his coauthors examined biomass burning (BB) events at Mt. Bachelor Observatory (MBO) during the summer of 2015. Biomass burning can emit large amounts of aerosols and gases into the atmosphere. These plumes contain compounds that react with sunlight to produce ozone, a health hazard to sensitive individuals. The photochemistry in BB plumes is poorly understand. Baylon and his coauthors addressed this knowledge gap by using MBO data to calculate ozone production rates and comparing these values with modeled values. Read the full paper here.
Lei Zhang, et al., A quantification method for peroxyacetyl nitrate (PAN) using gas chromatography (GC) with a non-radioactive pulsed discharge detector (PDD). Zhang and his coauthors developed a method for continuous peroxyacetyl nitrate (PAN) measurements using gas chromatography with a non-radioactive detector. PAN is a known precursor of ozone. Their method has high accuracy and is more readily deployable in field campaigns than the traditional gas chromatography method that utilizes a radioactive detector. Read the full paper here.

Here’s to Dr. Pao Baylon, newest PhD graduate in the Jaffe Group

Congratulations to Pao Baylon for the successful defense of his PhD thesis on May 31, 2017! His dissertation, titled Impact of Stratospheric Intrusions, Regional Wildfires, and Long-Range Transport Events on Air Quality in the Western United States, was the culmination of 6 years of hard work in the Jaffe Group. Pao was the first author on 3 peer-reviewed papers, and his fourth paper is currently in review. (See his papers on the Publications page.) He is now employed at the Idaho Department of Environmental Quality, Air Quality Division.

Pao Baylon dissertation celebration 5-31-2017 — Members of the Jaffe Group celebrating Pao’s PhD defense: (left to right) James Laing, Pao, Crystal McClure, Lei Zhang, Xi Gong, and Dan Jaffe

Pao shared some advice for graduate students: “Grad school is a cycle of ups and downs, and to survive this journey you should celebrate your triumphs and avoid dwelling on your lows.” And we celebrate you, Pao!

2 New papers published in October

Two Jaffe Group members have published peer-reviewed papers in October. Well done to Xi Gong and Pao Baylon for their outstanding work!

Xi Gong and her coauthors used a statistical approach, the Generalized Additive Model, to quantify ozone impacts from wildfires on 8 US cities. They showed that this approach can provide quantitative support for situations when large contributions from noncontrollable sources, such as wildfires, caused an exceedance of the EPA’s daily ozone standard.

Read the full paper here.

Pao Baylon and his coauthors looked at a Siberian biomass burning event in Spring 2015 that was observed at Mt. Bachelor Observatory and by satellite instruments, and also intercepted by a research aircraft. When the plume was in the eastern Pacific, it split into two plumes, one moving eastward toward MBO and the other moving northeast to Alaska and then south to the US Midwest. The second plume was observed by the aircraft in the Midwest. Baylon et al. found that the ozone production observed at MBO was higher than that of the aircraft plume. This was due to the plume at MBO being warmer and the aircraft plume being colder.

Read the full paper here.

Data permanently available in the UW archive

Datasets collected at Mt. Bachelor Observatory from 2004 to 2016 are now permanently archived and publicly available in the University of Washington ResearchWorks archive. The datasets include observations of ozone, carbon monoxide, mercury, nitrogen oxides, particulate matter and other atmospheric constituents. You can find the data by searching for Mt. Bachelor Observatory.

MBO datasets in UW ResearchWorks

UW ResearchWorks Archive

4 New first-author papers in 2017

The Jaffe Group has published 4 first-author papers so far this year. Stay tuned for more! Click the following links to see each paper:

James Laing, Dan Jaffe, Abbigale Slavens, Wenting Li, and Wenxi Wang, Can ΔPM2.5/ΔCO and ΔNOy/ΔCO enhancement ratios be used to characterize the influence of wildfire smoke in urban areas? Aerosol and Air Quality Research, doi: 10.4209/aaqr.2017.02.0069.
Honglian Gao and Dan Jaffe, Comparison of ultraviolet absorbance and NO-chemiluminescence for ozone measurement in wildfire plumes at the Mount Bachelor Observatory. Atmospheric Environment 166, 224–233, doi: 10.1016/j.atmosenv.2017.07.007.
Lei Zhang and Dan Jaffe, Trends and sources of ozone and sub-micron aerosols at the Mt. Bachelor Observatory (MBO) during 2004–2015. Atmospheric Environment 165, 143–154, doi: 10.1016/j.atmosenv.2017.06.042.
Dan Jaffe and Lei Zhang, Meteorological anomalies lead to elevated O3 in the western U.S. in June 2015. Geophysical Research Letters 44, 1990–1997, doi: 10.1002/2016GL072010.

Aerobiology workshop organized by Jaffe Group

Aerobiology workshop participants in Bend, Oregon - May 2017 — Aerobiology workshop participants in Bend, Oregon – May 2017

The Jaffe Group (specifically, Dan and Dee Ann) along with Andrew C. Schuerger of the University of Florida, Space Life Sciences Lab, organized a NASA-funded workshop in Bend, Oregon, at the beginning of May. This workshop gathered researchers from several universities and agencies to discuss a future experiment in “Aerobiology.” This is the study of the transport and biology of microbes in the atmosphere. Researchers plan to use Mt. Bachelor as a key sampling location to study the long-range transport of microbes in the global atmosphere. David Smith, now at NASA Ames Research Center, was one of the workshop participants. He is a UW alum (PhD Biology) and previously did ground-breaking work on aerobiology at Mt. Bachelor Observatory (see publications in 2011-2013).

In addition to PI Andrew Schuerger, David Smith, and Dan Jaffe, other participants were Co-PI Dale W. Griffin (US Geological Survey), Susannah M. Burrows (Pacific Northwest National Laboratory), Brent C. Christner (University of Florida), Cristina Gonzalez-Martin (University of La Laguna, Tenerife, Spain), Erin K. Lipp (University of Georgia), David G. Schmale (Virginia Tech), Boris Wawrik (University of Oklahoma), and Hongbin Yu (University of Maryland and NASA Goddard Space Flight Center).

Look for a future project studying microbes in the sky!

16 papers published in 2016!

2016 was a record year for papers for the Jaffe Group. This year, group members were first authors of 5 papers and contributing authors of 11 more papers, for a total of 16 papers.

The following are the group’s first-authored papers of 2016:

Pao Baylon et al., Interannual variability in baseline ozone and its relationship to surface ozone in the western U.S.
Nicole Briggs et al., Particulate matter, ozone, and nitrogen species in aged wildfire plumes observed at the Mount Bachelor Observatory
Lynne Gratz et al., Airborne observations of mercury emissions from the Chicago/Gary urban/industrial area during the 2013 NOMADSS campaign
James Laing et al., Physical and optical properties of aged biomass burning aerosol from wildfires in Siberia and the Western USA at the Mt. Bachelor Observatory
Crystal McClure et al., Carbon dioxide in the free troposphere and boundary layer at the Mt. Bachelor Observatory

See the Publications page for a full list of our published papers.

Ambrose publishes paper on new instrument for measurements of hydrogen cyanide

On June 1, Dr. Jesse Ambrose and colleagues published a paper in the journal Atmospheric Measurement Techniques that describes a new instrument for measurements of hydrogen cyanide (HCN), a selective tracer of biomass burning emissions, in the lower atmosphere. The instrument is capable of providing long-term HCN measurements in the background atmosphere and will serve as a valuable research tool for assessing the influence of wildfire and domestic wood burning smoke on atmospheric chemistry and air quality.

Read the paper here.