Figure 3. Map (from Stirling et al. 2004: fig. 1) showing average breakup dates (for 1971-2000) for western Hudson Bay (WH,) and southern Hudson Bay (SH, which includes James Bay). The mean date of breakup for areas I-III (SH) was 17 July ± 2 days and for area IV (WH), 14 July ± 2 days: earlier in WH than in SH, by a few days. This uses the old definition of 'breakup'- see previous post here.
{}