Deposition of dinitrogen pentoxide, N sub(2)O sub(5), to the snowpack at high latitudes

Dinitrogen pentoxide, N sub(2)O sub(5), is an important nighttime intermediate in oxidation of NO sub(x) that is hydrolysed on surfaces. We conducted a field campaign in Fairbanks, Alaska during November, 2009 to measure the flux (and deposition velocity) of N sub(2)O sub(5) depositing to snowpack using the aerodynamic gradient method. The deposition velocity of N sub(2)O sub(5) under Arctic winter conditions was found to be 0.59 plus or minus 0.47 cm/s, which is the first measurement of this parameter to our knowledge. Based on the measured deposition velocity, we compared the chemical loss rate of N sub(2)O sub(5) via snowpack deposition to the total steady state loss rate and found that deposition to snowpack is a significant fraction of the total chemical removal of N sub(2)O sub(5) measured within a few meters of the ground surface.