Observed changes in sea-ice floe size distribution during early summer in the western Weddell Sea

Digital aerial photographs are used to measure the change in floe size distribution over an area of the western Weddell Sea during the Ice Station Polarstern (ISPOL) program. The results show a significant increase in the number of small floes and brash ice over a 23 day period from 9 December 2004 to 1 January 2005. This is attributed to a net divergence of the pack ice, coupled with ice melt that caused ridges to relax and break into their component parts. The net effect is a significant increase in total floe perimeter that is important for lateral melt and primary production near floe edges.