Fig. 4: Flexural ice-shelf stress due to swell over 2003–2009.
From: Large-scale ice-shelf calving events follow prolonged amplifications in flexure
a–c, Number of days with σ = 10–30 kPa and σ ≥ 30 kPa for the Voyeykov (a), Wilkins RC (b) and Wilkins CL (c). d–f, Daily time-series of 60-day accumulated stress values normalized by the average yearly maxima using daily sea-ice lengths (Fig. 3d–i) and daily median wave heights (\({\hat{\sigma }}_{60}\); black curves), for the Voyeykov (d), Wilkins RC (e) and Wilkins CL (f). Time-series using climatological sea-ice lengths (daily average over the 7-year record) and daily median wave heights (\({\hat{\sigma }}_{60}^{{\rm{aice}}}\); purple curves) are included to indicate where variations are driven by swell (black and purple curves are similar) or by sea-ice lengths (black and purple curves separate). Daily time-series of total sea-ice lengths normalized by the total transect length are shown in the background (\({\hat{L}}_{{\rm{tot}}}\); shaded regions), where the transects extend to 10° N of the shelf fronts for Wilkins RC and Voyeykov, and 12° W for Wilkins CL (Methods). As in Fig. 3, the lighter shaded regions in a–f are after the calving events.
