Atmospheric form drag over Arctic sea ice using remotely sensed ice topography observations

by Alek Petty, Michel Tsamados, Nathan Kurtz (2017)



Petty, A. A., M. C. Tsamados, N. T. Kurtz (2017), Atmospheric form drag over Arctic sea ice using remotely sensed ice topography observations, J. Geophys. Res. Earth Surf., 122, doi:10.1002/2017JF004209.


Sea ice topography significantly impacts turbulent energy/momentum exchange, e.g. atmospheric (wind) drag, over Arctic sea ice. Unfortunately, observational estimates of this contribution to atmospheric drag variability are spatially and temporally limited. Here we present new estimates of the neutral atmospheric form drag coefficient over Arctic sea ice in early spring, using high-resolution Airborne Topographic Mapper (ATM) elevation data from NASA's Operation IceBridge mission. We utilize a new three-dimensional ice topography dataset, and combine this with an existing parameterization scheme linking surface feature height and spacing to form drag. To be consistent with previous studies investigating form drag we compare these results with those produced using a new linear profiling topography dataset. The form drag coefficient from surface feature variability shows lower values (<0.5-1 x 10-3) in the Beaufort/Chukchi seas, compared with higher values (>0.5-1 x 10-3) in the more deformed ice regimes of the Central Arctic (north of Greenland and the Canadian Archipelago), which increase with coastline proximity. The results show moderate interannual variability, including a strong increase in the form drag coefficient from 2013 to 2014/2015 north of the Canadian Archipelago. The form drag coefficient estimates are extrapolated across the Arctic with ASCAT satellite radar backscatter data, further highlighting the regional/interannual drag coefficient variability. Finally we combine the results with existing parameterizations of form drag from floe edges (a function of ice concentration) and skin drag to produce, to our knowledge, the first pan-Arctic estimates of the total neutral atmospheric drag coefficient (in early spring) from 2009-2015.


@article {petty2017,
    author = {Petty, Alek A. and Tsamados, Michel C. and Kurtz, Nathan T.},
    title = {Atmospheric form drag coefficients over Arctic sea ice using remotely sensed ice topography data, spring 2009–2015},
    journal = {Journal of Geophysical Research: Earth Surface},
    issn = {2169-9011},
    url = {},
    doi = {10.1002/2017JF004209},
    pages = {n/a--n/a},
    keywords = {Sea ice, Remote sensing, Mass balance, Energy balance, Dynamics, sea ice, Arctic, Atmospheric drag, momentum},
    note = {2017JF004209},