Barrow 2005

During the field study to Barrow, AK in 2005, we studied the vertical extent and impact of Arctic halogen chemistry.  We collected suites of data, including volatile organic compounds (VOCs), ozone, and gaseous elemental mercury (GEM) at altitudes of up to 300 meters with the aid of a tethered helium-filled balloon.  With these data, we observed that the halogen chemistry appears to be the most active in the lowest 100-200 meters of the atmosphere.  The vertical profiles of both VOCs and GEM are consistent with destruction by halogen-initiated chemistry involving species emitted from the snowpack.

We also collected surface-level VOC data over the frozen Arctic Ocean, including transects leading from the open water to the coast.  We are currently in the process of compiling these data with halogen oxide concentrations and meteorological conditions collected during the LEADEX 2005 campaign to better understand the extent of the impact of open water (leads) on the extent of local-scale halogen chemistry.

As a follow-up to this work, an effort is currently underway to create a 1-D computer model in order to simulate the chemistry of VOCs, halogens, and mercury in the vertical direction.  This model will enable the potential sources of halogen chemistry (snowpack/ice, aerosols, or a combination of both) to be individually activated and deactivated.  This will allow us to compare the model results with the vertical profiles obtained with the balloon, enabling us to further understand the processes that deplete ozone and mercury during springtime in the Arctic.

You can see photos from the Barrow 2005 field study here.