New article published

Carbonaceous species and humic like substances (HULIS) in Arctic snowpack during OASIS field campaign in Barrow

Snowpacks contain many carbonaceous species that can potentially impact on snow albedo and arctic atmospheric chemistry. During the OASIS field campaign, in March and April 2009, Elemental Carbon (EC), Water insoluble Organic Carbon (WinOC) and Dissolved Organic Carbon (DOC) were investigated in various types of snow: precipitating snows, remobilized snows, wind slabs and depth hoars. EC was found to represent less than 5% of the Total Carbon Content (TCC = EC + WinOC + DOC), whereas WinOC was found to represent an unusual 28 to 42% of TCC. Snow type was used to infer physical processes influencing the evolution of different fractions of DOC. DOC is highest in soil influenced indurated depth hoar layers due to specific wind related formation mechanisms in the early season. Apart from this specific snow type, DOC is found to decrease from precipitating snow to remobilized snow to regular depth hoar. This decrease is interpreted as due to cleaving photochemistry and physical equilibration of the most volatile fraction of DOC. Depending on the relative proportions of diamond dust and fresh snow in the deposition of the seasonal snowpack, we estimate that 31 to 76% of DOC deposited to the snowpack is reemitted back to the boundary layer. Under the assumption that this reemission is purely photochemical, we estimate an average flux of VOC out of the snowpack of 20 to 170 µg C  m-2 h-1. Humic like substances (HULIS), short chain diacids and aldehydes are quantified, and showed to represent altogether a modest (<20%) proportion of DOC, and less than 10% of DOC + WinOC. HULIS optical properties are measured and could be consistent with aged biomass burning or a possible marine source.

Talks at Bishop’s University & Dawson College

Recently, I gave 2 talks on my research activities with some information on statistics and data analysis (at Bishop’s University: 01 Mar 2012 & Dawson College: 07 Mar 2012) for environmental analytical projects. It’s been fun and there was a lot of discussion with students during and after the talk.

Among other things I explained, why chemists typically measure samples 3 times (hint: check the t-table) and what things to consider, before going sampling (representativity, homogeneity and stability). All this, in the (practical) context of snow sampling from surfaces and pits during my field research in Alert, NU and Barrow, AK.

Contribution at upcoming AGU Fall Meeting

I will be presenting a paper at the upcoming AGU Fall Meeting as part of the OASIS session A08: Ocean-Atmosphere-Sea Ice-Snow (OASIS) Interactions in Polar Regions: Results From Recent Field Campaigns:

Gregor Kos, Adechina Nafissa, Dwayne Lutchman, Roya Mortazavi, Parisa Ariya
(Semi)volatile Organic Compounds and Microbiological Entities in Snow during OASIS Barrow 2009

Abstract ID 723572
I will not be able to present myself, but one of the co-authors will be there to present the poster.

Preparing GC-MS Measurements

Things have been incredibly busy in the weeks after my return. Some reports had to be finished and I am quite actively working on revisions of my manuscript drafts. There has been some follow-up on the Barrow campaign – nice to see some photos of the researchers continuing their work.

Meanwhile I started preparing GC-MS measurements of my own samples. I have help from a graduate student from France doing an internship in our labs! I am quite busy training her on the instrument, sample preparation, data analysis and calibration, she will be ready to start running samples in a few weeks time.