Extended Data Figure 3: Sea-ice drift speed comparison between the NSIDC and Kwok et al. data for the period 1992–2003.
From: Sea-ice transport driving Southern Ocean salinity and its recent trends
a, b, Low-pass filtered, 21-d running mean for the original (a) and bias-corrected (b) daily meridional NSIDC sea-ice drift speed compared with the low-pass filtered daily meridional Kwok et al. data. Contours mark the number of grid boxes and the blue line marks the fitted least squares linear regression line. c–e, Mean sea-ice drift speed of the original (c) and bias-corrected NSIDC (d) and Kwok et al. (e) sea-ice drift speed. The arrows denote the drift vectors. f, R.m.s. differences between the annual mean bias-corrected NSIDC and Kwok et al. sea-ice drift speed. The thick grey line in c–f marks the mean sea-ice edge (1% sea-ice concentration). Data points were compared when both data sets were available. See Methods for details.
