Dynamic topography of the ice‐covered Arctic Ocean from ICESat

[1] We construct the dynamic ocean topography (DOT) of the Arctic Ocean, for five ICESat campaigns (winter of 2004–2008), using sea surface height estimates in open leads. Results show that the mean winter DOT over the Arctic Ocean varies by ∼1 m and features a distinct dome of ∼40 cm over the Beaufort Sea. Standard deviation of the mean field is ∼20 cm. Spatial coherence between the five winter DOTs is consistently high (>0.9), whereas the coherence between the DOTs and the winter (DJFM) sea-level pressure fields over the Arctic Basin is variable. This suggests persistence of the underlying hydrodynamic processes at interannual time-scales compared to seasonal atmospheric forcing. Comparison of dynamic heights (DH) from hydrographic surveys and the DOT in 2008 shows a remarkable correlation of 0.92. The geostrophic velocity fields computed from the DOT and interpolated DH fields highlight the smaller scale oceanographic features in the satellite estimates.

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