Wednesday, April 8, 2015

Colorado Snow Study April 2015

In early April, Prof. Andrew Ault, Dr. Jessica Axson, and graduate student Hongru Shen from the Ault lab along with Dr. Jessie Creamean from NOAA, Boulder set out to Silverton Colorado for a short field study to collect snow and aerosol samples from a remote site in the San Juan Mountains of Colorado to examine dust deposition in the area. 
Google Map showing Silverton, CO and the Swamp Angel Sampling Site in the San Juan Mountains. 

April 2nd: After arriving in Silverton the night before, the four of us set to out meet with Chris Landry and Jay Wlez from the Center for Snow & Avalanche Studies (CSAS; http://www.snowstudies.org) to trek out to the Swamp Angel Study Plot. To get to the site, we had to use snow shoes and carry in the instrument and supplies. The stunning location was surrounded by mountain ridges, including Red Mountain and Trico Peak.
Prof. Ault and Hongru Shen starting their trek to the sampling site for set up. 

Dr. Creamean, Jay Welz, and Chris Landry at the Swamp Angel Site
To collect aerosols, we used a 3 stage impactor with three different size cuts at <700 nm, 700 nm – 2.5 mm, and 2.5 mm<.  The impactor was run on battery power to avoid aerosol production and was kept safe from weather in an metal enclosure. 

Impactor at the sampling site.

For each night sampling, the instrument was strapped to the platform for stability (Show in picture are Prof. Ault, Dr. Axson and Hongru Shen). 
April 3rd : To sample during the day and night, we changed samples every morning around 9:00-10:00 and again at 16:00-16:30.  Andy and Jessie head off to the airport, with Hongru and I remaining to collect 2 more days of sampling. We believe over Thursday night that we may have had a small dust event, evident by the loading on our top stage (2 um<) the following morning.
Sampling stage 1 (2.5 um<) after dust event. 

April 4th: For the next two days of sampling, there was no visible loading on the top stage, but very small and still visible loading on the bottom two stages. Snow samples were collected all three days for offline analysis using IC and NTA.

April 5th:  After packaging and shipping all of our equipment, Dr. Axson and Hongru Shen traveled back to Ann Arbor. We both enjoyed the beautiful mountain views from the flight from Durango to Denver.
Image of the Rocky Mountains on flight from Durango to Denver Colorado. 

Tuesday, April 7, 2015

MGU Symposium

Several members of the Ault Lab participated in the Michigan Geophysical Union (MGU) Symposium hosted by the Atmospheric, Oceanic, and Space Sciences and Earth and Environmental Sciences Departments at the University of Michigan on Wednesday, April 1.

Undergraduate Sydney Niles and third year graduate student Amy Bondy presented their work on the characterization of aerosol particles collected during the SOAS Field Campaign.
First year rotation student Rachel Kirpes presented her work characterization of aerosol particles collected in Barrow, AK.


First year rotation student Garrett Welshofer presented his work on developing glassware to study heterogeneous reactions on aerosol particle surfaces.
Second year grad student Becky Craig presented her work on surface enhanced Raman spectroscopy and computer-controlled Raman microspectroscopy and their application to single particle aerosol analysis.


Congratulations to Becky Craig, Matt Gunsch (third year grad student, Pratt Lab), and Evan Schwartz (undergraduate, Pratt Lab) for winning 1st place, 2nd place, and the People's Choice Award at the symposium!