Summertime surface O3 behavior and deposition to tundra in the Alaskan Arctic

• Published in: Journal of Geophysical Research: Atmospheres
• Main Authors: Van Dam, Brie, Helmig, Detlev, Doskey, Paul V., Oltmans, Samuel J.
• Format: Text
• Language: unknown
• Published: Digital Commons @ Michigan Tech 2016
• Subjects: College of Forest Resources and Environmental Science; Atmospheric Sciences; Forest Sciences; Life Sciences; Arctic; Tundra
• Online Access: https://digitalcommons.mtu.edu/michigantech-p/3358; https://doi.org/10.1002/2015JD023914

Atmospheric turbulence quantities, boundary layer ozone (O3) levels, and O3 deposition to the tundra surface were investigated at Toolik Lake, AK, during the 2011 summer season. Beginning immediately after snowmelt, a diurnal cycle of O3 in the atmospheric surface layer developed with daytime O3 maxima, and minima during low-light hours, resulting in a mean amplitude of 13 ppbv. This diurnal O3 cycle is far larger than observed at other high Arctic locations during the snow-free season. During the snow-free months of June, July, and August, O3 deposition velocities were ~3 to 5 times faster than during May, when snow covered the ground most of the month. The overall mean O3 deposition velocity between June and August was 0.10 cm s-1. The month of June had the highest diurnal variation, with a median O3 deposition velocity of 0.2 cm s-1 during the daytime and 0.08 cm s-1 during low-light conditions. These values are slightly lower than previously reported summertime deposition velocities in northern latitudes over tundra or fen. O3 loss during low-light periods was attributed to a combination of surface deposition to the tundra and stable boundary layer conditions. We also hypothesize that emissions of reactive biogenic volatile organic compounds into the shallow boundary layer may contribute to nighttime O3 loss.