Welcome to the Pratt Lab blog! Dr. Kerri Pratt is an assistant professor in the Departments of Chemistry and Earth & Environmental Sciences and faculty associate of the Program in the Environment at the University of Michigan. We study the chemical interactions of atmospheric trace gases, particles, clouds, and snow, with a focus on the Polar Regions and wintertime environments. Our interdisciplinary research has relevance to climate change, air quality, and human health. As an analytical chemistry lab, we primarily apply novel mass spectrometry techniques to our field research. We invite you to follow our adventures in (and outside!) the lab!

Sunday, December 17, 2017

PhD Graduation - Congratulations to Dr. Matthew Gunsch!

Congratulations to Dr. Matthew Gunsch, the first PhD graduate of the Pratt Lab!!! Here are photos from winter commencement!

Sunday, December 10, 2017

Come see the Pratt Lab at AGU Fall Meeting!

Come see the Pratt Lab at the 2017 American Geophysical Union Fall Meeting! Here's our line-up:

Monday, Dec. 11, 8:00-12:20, A11K, Tropospheric Composition in Cold Environments: Sources, Processes, and Impacts Posters (session co-organized by Prof. Pratt)
- PhD student Rachel Kirpes poster A11K-2015
- Postdoc Peter Peterson poster A11K-2022
- PhD student Angela Raso poster A11K-2023

Monday, Dec. 11, 13:40-15:40, A13O, Tropospheric Composition in Cold Environments: Sources, Processes, and Impacts I Oral Session (co-organized by Prof. Pratt)
- PhD student Angela Raso talk A13O-07, 15:10-15:25
- PhD student Stephen McNamara talk A13O-08, 15:25-15:40

Friday, Dec. 11, 10:20-10:35, A52H-01, Talk by Prof. Kerri Pratt: "Influences of Sources and Aqueous Processing on the Molecular Composition of Dissolved Organic Compounds in Cloud Water"

We hope to see you in New Orleans!

Friday, November 17, 2017

Michigan News cover story about UMBS prescribed burn & Pratt Lab research!

The U-M Biological Station's historic prescribed burn and the Pratt Lab contribution to measuring the resulting smoke particles was covered in a recent feature article by Michigan News! PhD students Nick and Nate were highly successful keeping three lasers aligned for particle sizing and LDI with subsequent TOF-MS analysis of individual aerosol particles while the Aerodyne Research mobile lab was moving! They measured tens of thousands of particles in a very short period of time! I'm so impressed!

Pratt Lab PhD students Nick Ellsworth and Nate May with the Aerodyne Research mobile laboratory. Image credit: Roger Hart/Michigan Photography

Tuesday, November 14, 2017

Prof. Kerri Pratt awarded ACS James J. Morgan Early Career Award in Environmental Chemistry!

Prof. Kerri Pratt was awarded the 2018 American Chemical Society James J. Morgan ES&T Early Career Award Lectureship in Environmental Chemistry! Here's link to the ACS write-up. This is the only early-career award given out by the ACS Division of Environmental Chemistry.

Monday, November 13, 2017

New Arctic molecular halogen paper published!

Congratulations to former Pratt Lab post-doc Dr. Siyuan Wang for the publication of his paper "Molecular halogens above the Arctic snowpack: Emissions, diurnal variations, and recycling mechanisms" in the Journal of Geophysical Research - Atmospheres. Dr. Wang is now a prestigious Advanced Study Program postdoctoral fellow at the National Center for Atmospheric Research in Colorado!

Welcome Jacinta!

Welcome Jacinta Edebeli! Jacinta is a third-year PhD student studying chemical reactivity in snow and ice with Prof. Dr. Markus Ammann and Dr. Thorsten Bartels-Rausch at the Paul Scherrer Institute in Switzerland. She is visiting for five months to participate in our urban snow-air interactions study in Michigan this winter! She will be deploying our ambient ion monitor-ion chromatography instrument to measure inorganic trace gases and particles.

Monday, November 6, 2017

Stephen presents CIMS research at the ANACHEM Symposium

On Nov 2, I (Stephen) attended the Detroit Association of Analytical Chemists (ANACHEM) annual symposium at Burton Manor in Livonia, MI. My poster, titled "Measurements of Trace Halogen Gases in the Alaskan Arctic using Chemical Ionization Mass Spectrometry", focused on the use of our chemical ionization mass spectrometer to measure trace halogen gases near Utqiagvik, Alaska in spring 2016. This was a great opportunity to share my work with other analytical chemists from diverse backgrounds at many of the regional universities. The plenary speaker, Prof. Paul Cremer from Penn State University, was the recipient of the 2016 ANACHEM Award and gave an excellent talk on his group's multi-disciplinary work in biophysics and biological interfaces. I was also able to catch up with my former undergraduate advisor at Michigan State, Prof. Dana Spence, and visited with the old research group!

Friday, November 3, 2017

Rachel presents at MMMS

On November 1st, I (Rachel) attended the Michigan Microscopy and Microanalysis Society meeting. I presented a poster on my work, "Multiple Approaches Applied for the Microscopic Characterization  of Atmospheric Particles show Sulfates with Unique Morphology in the Arctic".
It was also a great opportunity to learn about other research carried out at the Michigan Center for Materials Characterization and at other institutions across the state. I also learned a lot from the vendors who make the instruments and software I use regularly for my research!

Friday, October 20, 2017

Sampling Smoke from a Controlled Burn at UMBS!

On Tuesday October 10th there was a controlled burn at the University of Michigan Biological Station. These burns are done every 20 years or so, allowing researchers to study how the forest responds to and recovers from fires. We were interested in sampling the smoke plume under these controlled conditions to gain a greater understanding that can be applied to wildfires that are currently ranging across the western US. Pratt Lab graduate students Nate and I (Nick) collaborated with Conner Daube and Ed Fortner from Aerodyne Research to conduct measurements the smoke plume during the burn. We used our new aircraft-aerosol time-of-flight mass spectrometer (A-ATOFMS) to sample over 25 thousand aerosol particles! In addition we also used a DRUM impactor to collect particle samples for off-line analysis by electron microscopy. This was an excellent opportunity to learn about the impacts of fresh biomass burning aerosols on air quality in a minimal risk situation. This field study was conducted in the incredible Aerodyne Mobile Laboratory! 
 Aerodyne Mobile Lab as we prepared for the burn.

 An inside view of the Lab. In the very back of the picture you can see Maverick (A-ATOFMS).

As a result of wet weather conditions, this burn was incomplete (evidenced by the green ferns in the burn area). It did however create plenty of smoke for us to sample.

 Sampling performed on Riggsville Road near the Biological Station.

Aftermath of the controlled burn - As you can see the moisture prevented a complete burn, but we still had plenty of aerosol particles!

Saturday, September 30, 2017

Welcome Nick and Christian!

Welcome Nick Ellsworth and Christian Keiser! Nick is a first-year rotation graduate student who recently received a B.S. degree at Utah Valley University, and Christian is a first-year undergraduate student participating in the Undergraduate Research Opportunity Program. Welcome to the Pratt Lab!

Friday, September 15, 2017

Arctic oil field aerosols paper published!

Congratulations to former Pratt Lab members Dr. Matt Gunsch (recent Ph.D.) and Dr. Katie Kolesar (post-doc) and current Pratt Lab Ph.D. student Rachel Kirpes for their paper describing the chemical composition of atmospheric particles transported to Utqia─ívik (Barrow), AK from the Arctic Ocean and Prudhoe Bay oil fields! "Contributions of transported Prudhoe Bay oil field emissions to the aerosol population in Utqia─ívik, Alaska" was recently published in Atmospheric Chemistry and PhysicsPlease check out the paper!

Thursday, September 7, 2017

Arctic Molecular Iodine Paper Published in PNAS!

Prof. Kerri Pratt and PhD student Angela Raso (co-advised by Prof. Paul Shepson at Purdue Univ.) completed the first measurements of Arctic tropospheric I2, produced from the sunlit coastal snowpack. Read about "Active molecular iodine photochemistry in the Arctic" in the Proceedings of the National Academy of Sciences of the U.S.A.!

Press Release Links:
Michigan News: Chemists discover molecular iodine in Arctic atmosphere, released by snowpack
Purdue News: First measurements of iodine in the Arctic reveal questions about air pollution

Tuesday, August 29, 2017

Thursday, August 24, 2017

Eclipse 2017!

On August 21st, the Pratt and Ault labs took an afternoon break to see the near-total solar eclipse over Ann Arbor! Fortunately, the unpredictable Michigan weather cooperated enough to see the 80% coverage before storm clouds rolled in. We all had a great time joining the hundreds of people who gathered on the UM Diag to view this amazing event!
The Pratt and Ault Labs on the UM Diag

Near 80% coverage, taken from a cell phone camera and behind solar eclipse glasses!
The tree canopy on the Diag acting as a camera obscura, projecting the crescent of the sun! Hundreds of spectators in the background
The cloud cover was just right to snap an unfiltered photo of the sun

Tuesday, August 15, 2017

There's No Place Like Nome!

The town of Nome is located right on the Norton Sound, part of the Bering Sea. I enjoyed beautiful (if chilly) beach views throughout my trip!
Last week I (Rachel) took my first (sub)Arctic research adventure to Nome, Alaska! By now, the Pratt Lab is well acquainted with Alaskan travels, but this trip was full of firsts for me and the group: my first trip to Alaska, my first time on an icebreaker, the first deployment of our new MOUDI, and the first helicopter trip for both the MOUDI and me! 

My first morning in Nome, I had a chance to walk around and tour the town - which took about 30 min! I was able to see all the highlights - I watched gold mining dredges from the beach, grabbed a photo of the largest gold pan in North America, and saw the arch marking the end of the famous Iditarod sled dog race that happens every spring. 
The largest gold pan welcomes everyone to Nome
The end of the Iditarod, which runs from Anchorage to Nome

The Araon has arrived in Nome!
I was in town to visit the icebreaker Araon, a Korean research vessel, and install our MOUDI aerosol impactor onboard. The Araon left from Incheon, South Korea in late July and made a stop in Nome before continuing on from two research legs in the Alaskan Arctic, through the Chukchi and Beaufort Seas. We are collaborating with Prof. Saewung Kim's research group from the University of California, Irvine to collect aerosol particles with our MOUDI throughout the research cruise (thanks Blanca!) for later chemical analysis.

Due to the logistics of transporting people and cargo (via helicopter!), I arrived aboard the Araon with time to take a tour and get acquainted with the ship before my equipment arrived. I also had the neat/very stressful experience of watching from the helideck as my brand new instrument and supplies were transported via cargo net beneath the helicopter to the ship. What seemed like a short 3 minute trip when I was in the helicopter seemed like a lifetime as I watched my cargo get flown over empty air and open water. Luckily, everything was well packed in sturdy crates :)
The most stressful part of the trip!
A view of the ship from the compass deck.
KOPRI is the Korean Polar Research Institute,
our collaborators for this study.

Step 1: make sure the instrument enclosure is really secure!
Step 2: install MOUDI inside and set up for sampling! 

I only had a day and a half (about one day once my cargo was onboard) to get the instrument set up and ready for sampling, so we had to work hard. I didn't mind long hours though - I had a wonderful view and there was plenty of sunlight - at the beginning of August in Nome, sunrise is ~ 6 am and sunset is ~ midnight. With so much light, I didn't feel tired!

A beautiful view from the ship around 11 pm. 
By the next afternoon, we were ready for sampling and it was sadly time for me to leave. The ship was great - wonderful Korean food (kimchi at every meal!), comfortable cabins, and extensive laboratories. Even with my short time onboard, I was able to meet many of the other scientists for the Arctic cruise and learn about the awesome research being conducted! Now the MOUDI is collecting samples, and in a month or two I'll have new data to work with. It was an awesome, fun, and productive few days in the field.
A final view of the ship as I took the helicopter back to shore. 

By the time I left, Nome was quite the research hub! In addition to the Araon, the USCGC Healy, the UAF research vessel Sikuliaq, a Japanese research vessel, and a NASA jet all made appearances. I'm excited to be able to say I at least had a small part in all the science happening!
A few of the research vessels in Nome my last day.
Before I left Nome completely, I was able to do a little more exploring and see some wildlife. I fulfilled a personal goal of seeing musk ox (they're so cool/weird looking!), I saw streams full of salmon, and lots of birds (my parents are jealous!) I didn't expect 70 degrees and sunny in Alaska, but it made for a beautiful way to wrap up my first Alaskan experience. 
Musk Ox in the tundra
look closely, the water is full of salmon!

peregrin falcon on the tundra
an Arctic tern (so neat!) in flight

Wednesday, August 9, 2017

2017 Karle Symposium

5 graduate students and 1 REU student from the Pratt Lab presented their research at the 2017 University of Michigan Department of Chemistry Karle Symposium. PhD student Nate May won a travel award sponsored by the Dow Chemical Company for an outstanding student talk for his research on "Environmental Chemistry Research in the General Chemistry Laboratory." Congratulations to everyone who presented!

Nate May - Talk: "Environmental Chemistry Research in the General Chemistry Laboratory

Stephen McNamara - Talk: "Nitrogen Oxide Influence Chlorine Chemistry in the Alaskan Arctic"

Tuesday, August 8, 2017

Congratulations to the new Dr. Matthew Gunsch!

Congratulations to the first Pratt Lab Ph.D. - Dr. Matthew Gunsch!! Today he defended his dissertation titled "Online single particle chemical characterization of aerosol populations in remote environments".
Defense presentation

Congratulating Dr. Gunsch!

Dr. Gunsch & Prof. Pratt

Friday, July 28, 2017

Stephen, Peter, Rachel, and Kerri attend the 2017 Connaught Summer Institute in Arctic Science

Stephen, Peter, Rachel, and Kerri spent a week at the Nottawasaga Inn in Alliston, Ontario, Canada for the 2017 Connaught Summer Institute (CSI) in Arctic Science. Supported by the Connaught Fund at the University of Toronto, the CSI invites students and speakers from a variety of backgrounds in academia, industry, and government organizations to discuss climate change and the various methods to understand its effects on the Arctic. Prof. Pratt gave three invited lectures on Arctic halogen chemistry and changing aerosol chemistry, highlighting the work of various group members! The 2017 program can be found here.

Stephen, Rachel, and Peter also presented posters on their ongoing research in the Pratt Lab.

<Stephen Poster picture Waiting on pictures to be posted on CSI website!>
Stephen presented his poster on NOx influenced chlorine chemistry in Utqiagvik, AK, results from the 2016 field campaign. He was one of two Ph.D. students to win an Outstanding Poster Award!

<Peter Poster picture>
Peter presented his poster on airborne reactive bromine observations from the 2012 BROMEX study. His poster won the Outstanding Post-Doc Fellow Poster Award!

<Rachel Poster picture>
Rachel presented her work on aerosol chemical composition and mixing states in the winter-spring Arctic.

In our free time, we were able to enjoy some quality mini-golf on the indoor course at the hotel!
Peter was victorious, coming in at a stunning 15 over par final score

Thanks to the Connaught Summer Institute Organizing Team for the invitation and their hard work!

Friday, June 30, 2017

Congratulations Nate!

Pratt Lab PhD student Nate May was awarded a Chemistry One-Term Dissertation Fellowship for his research excellence! Congratulations Nate!!

Monday, June 26, 2017

Arctic bromine paper published!

Congratulations to Pratt lab postdoc Peter Peterson for his paper detailing the first observations of reactions on aerosol particles enabling the transport of reactive bromine aloft (decoupled from the snow surface)! "Observations of bromine monoxide transport in the Arctic sustained on aerosol particles was recently published in Atmospheric Chemistry and Physics. Please check out the paper!

Monday, June 19, 2017

Prof. Pratt receives college teaching award!

Prof. Kerri Pratt was awarded the 2017 Individual Award for Outstanding Contributions to Undergraduate Education from the University of Michigan College of Literature, Science, and the Arts! Nominations for this award are eligible from all levels of teaching faculty in the college (not just junior faculty), so this is super rewarding. This award to Prof. Pratt recognizes "novel opportunities for learning through authentic research experiences" in our newly developed general chemistry laboratory course! Together Prof. Pratt and PhD students Nate May and Stephen McNamara have now each won teaching awards for our development of this new snow chemistry research course!

Monday, June 12, 2017

Welcome Nour and Jia!

Welcome Nour Abduljalil and Jia Shi for the summer! Nour is a junior Chemistry undergraduate student at Towson University in Maryland and joined the Pratt lab this summer as a Chemistry REU participant!  Jia is an incoming Chemistry graduate student completing a summer rotation in the Pratt Lab. He is a former McNair scholar who recently graduated with a B.A. in Chemistry from St. Olaf College. We are excited for you both to be in the lab this summer!

Monday, June 5, 2017

Pratt Lab at the 2017 Canadian Chemistry Conference

Prof. Kerri Pratt, along with post-docs Dr. Peter Peterson and Dr. Siyuan Wang and Ph.D. students Matt Gunsch and Rachel Kirpes, presented their results from a number of different Arctic research projects currently ongoing in the group! The 2017 Canadian Chemistry Conference was a week-long conference in Toronto, Canada (May 28- June 1st, 2017) that attracted thousands of chemists to share their work and engage in productive discussions. It was great opportunity to network and touch base with many of our collaborators! The following presentations were given by Pratt Lab members:

Prof. Kerri Pratt: Invited talk, "Snowpack Molecular Halogen Production in the Springtime Arctic" highlighting our Arctic halogen measurements and modeling. 

Dr. Peter Peterson: Talk: "Comparison of Bromine Processes Over Coastal and Inland Arctic Snowpacks" featured airborne reactive bromine measurements collected during the BROMEX 2012 study near Utqiagvik (Barrow), AK.

Dr. Siyuan Wang: Talk: "Snowpack Emissions of Cl2 and its Fate in the Arctic Boundary Layer: A Modeling Study" highlighted modeling studies of Cl2 emissions from Arctic snowpacks.

Matt Gunsch: Talk: "Chemical Characterization of Atmospheric Particulate Matter within the Prudhoe Bay Oilfields, Alaska" featured results from our 2016 summer field study in the Prudhoe Bay oil fields of Alaska's North Slope

Rachel Kirpes: Poster: "Influence of Secondary Sulfate on Arctic Sea Spray Aerosol and Organic Aerosol Mixing States during Winter and Spring" featured single particle analysis from our 2014 field study near Utqiagvik (Barrow), AK.

We also took advantage of a free evening to check out a Blue Jays game!

(Post by Peter!)

Friday, May 19, 2017

Congratulations Rashad - 4th Place at International Science Fair!

Congratulations to summer 2016 D-RISE Pratt Lab researcher Rashad Prendergast (Cass Technical High School) for being awarded 4th Place in Earth & Environmental Sciences at the 2017 Intel International Science and Engineering Fair in Los Angeles, CA! He presented his summer research poster titled "Impact of Road Salt Usage on Atmospheric Concentrations of Cl and Na PM2.5"! Great job Rashad, and thank you to his mentor Pratt Lab post-doc Dr. Katie Kolesar!

Wednesday, May 17, 2017

Pratt Lab Arctic research news story published!

We are really excited about the recent write-up about our Arctic aerosol research! This journalist received an investigative journalism grant to write this story, which included visiting our Arctic field site in summer 2015!

Teaser - read the story to learn about 'Maverick' and the 'Death Star'! :-)

Monday, May 8, 2017

Congratulations to Nate and Stephen!

Congratulations to Pratt Lab PhD students Nate and Stephen for receiving UM Department of Chemistry awards! Nate May was awarded the George Ashworth Analytical Chemistry Fellowship and the Alumni Fund Outstanding Student Research Award! Stephen McNamara was awarded the Florence Fenwick Outstanding Graduate Student Instructor Award for his efforts in helping development our general chemistry lab course focused on authentic environmental chemistry research! Congratulations Nate and Stephen!!!

Friday, April 28, 2017

Anna and Annie Graduate!

Congratulations to senior undergrads Anna Leemon and Annie Barget on their graduations from the University of Michigan!! Anna graduated with a B.S. degree in Chemistry and will be joining the Stanford University Teacher Education Program in the fall to earn a M.S. in Education to teach high school chemistry! Annie graduated with a B.S. degree in Biomolecular Science and will be continuing research with us this summer as a Michigan Space Grant Fellow! Congratulations! We are so proud!
Prof. Pratt and graduate Anna Leemon
Prof. Pratt and graduate Annie Barget

Arctic snowpack molecular halogen production paper published!

Congratulations to former Purdue Univ. PhD student Kyle Custard and current student Angela Raso for their paper detailed the first measurements of snowpack Br2 and Cl2 fluxes - and observation of the Arctic snowpack as a source of Cl2 and BrCl! "Production and Release of Molecular Bromine and Chlorine from the Arctic Coastal Snowpack" was recently published in ACS Earth and Space Chemistry. Please check out the paper! 

Congratulations to Alexa, Claire, Logan, and Maddie!

Congratulations to Pratt Lab undergraduate students Alexa Watson, Claire Mattson, Logan Vear, and Maddie Parks who were all awarded HHMI summer research fellowships to continue research in the Pratt Lab! These fellowships were for alumni of the HHMI-sponsored Authentic Research Connection.

Rachel Goes to Washington!

Earlier this month, Pratt Lab graduate student Rachel Kirpes was sponsored by the American Geophysical Union (AGU) to attend the AAAS Catalyzing Advocacy for Science and Engineering (CASE) workshop in Washington, D.C. To read more about what she learned from this experience, check out her post on AGU's science and policy blog, The Bridge!

Monday, April 17, 2017

Congratulations to Annie, Stephen, and Rachel!

Graduating senior Annie Barget and PhD students Stephen McNamara and Rachel Kirpes were awarded fellowships from the Michigan Space Grant Consortium! Congratulations!!

Tuesday, April 11, 2017

Stephen Volunteers in "You Be the Chemist" Event at UM

I (Stephen) gave a presentation about research in the Pratt Lab to regional elementary and middle school students participating in the "You Be the Chemist" Challenge held at the University of Michigan on March 23rd. This event, put on by local firm PVS Chemical, is part of a national program in which 5-8 grade students participate in a chemistry academic challenge, similar to a quiz bowl, supported by local industry and academic institutions. For more information, visit their website!

Before the competition, the students learned about research at UM through presentations and demonstrations by lab groups in the Chemistry department. It was a great opportunity for students to see what a career in chemistry research would look like!
Learning about polymers by making Shrinky Dinks!

Monday, April 10, 2017

Pratt Lab featured in Pacific Northwest National Lab highlight!

Pratt Lab PhD student Rachel Kirpes and rotation student Nicole Olson are featured on the Pacific Northwest National Laboratory Environmental Molecular Sciences Laboratory website!

Sunday, April 9, 2017

Alaska Dispatch News covers Pratt Lab paper!

The Alaska Dispatch News (Anchorage daily newspaper) covered Katie's recent paper on Prudhoe Bay emissions impacting ultrafine particle growth on the North Slope!
Link to paper published in Atmospheric Environmenthttp://www.sciencedirect.com/science/article/pii/S1352231016309785

Friday, April 7, 2017

Pratt Lab presents research at the Michigan Geophysical Union meeting

At the 14th Annual Michigan Geophysical Union meeting, six graduate students and five undergraduate students from the Pratt Lab presented their research. The topics highlighted the diversity of research that we are pursuing in our group. PhD student Matt Gunsch won first place in the Chemistry Section for his research on "Chemical Characterization of Atmospheric Particulate Matter from Prudhoe Bay, Alaska" and PhD rotation student Nicole Olson won second place in the Chemistry section for "Single Particle Analysis of Ambient and Laboratory Generated Lake Spray Aerosols". Senior Annie Barget won first place for the Michigan Geophysical Union Undergraduate category for her work on "Effects of Wind Speed and Sea Ice Conditions on the Chemical Composition of Coastal Arctic Snow". Congratulations to everyone who presented!

Matt Gunsch presenting his first place research on the single particle chemical composition in Prudhoe Bay, Alaska

Nicole Olson with her award winning research on lake spray aerosols

Annie Barget with her award winning research on the connections between wind speed, sea ice leads and the chemical composition of snow

Anna Leemon presenting on Arctic snow composition during the spring melt

Logan Vear presenting research on the influence of wildfires on cloud water 

Ryan Cook talked about the organic composition of aerosols observed at the University of Michigan Biological Station during summer 2014

Alexa Watson discussed her work calibrating the ATOFMS using relative sensitivity factors

Nate May presented on the physical and chemical characteristics of lake spray aerosol

Rachel Kirpes discussing her research using microscopy to identify elemental composition and functional groups present in particles from Utqiagvik, Alaska

Stephen McNamara presented data on atmospheric chlorine chemistry in the springtime Arctic