Data Processing: The compiled data is provided as-is, with both in-situ and detided velocity fields. De-tiding occurred for nine out of the 46 sections, using the Oregon State University tidal inversion software (Padman and Erofeeva, 2004); seven of these nine required additional quality control to remove ship velocities from the record. The origin of each cruise’s data can be found in the ‘chukchi_data_sources’ file. The interpolation of hydrographic casts to create a mean section followed the procedures of Pickart (2004), in which the casts are horizontally relocated to their respective isobaths on a mean bathymetry prior to interpolation by a Laplacian-spline scheme using a uniform grid of 3 km in the horizontal, and 5 m in the vertical (Smith and Wessel, 1990). Interpolation of in-situ sections followed a similar procedure; however, the horizontal location of casts was not adjusted.