In this study, the CVice_cover was calculated twice for the 2013–2014 winter to assess intra-annual variation of ice covers. The first CVice_cover was calculated with five FOW3 input images, acquired from 21 November 2013 to 25 February 2014. Four FOW3 input images, acquired from 15 December 2013 to 25 February 2014, were used for the second CVice_cover (Figure 5). Since there were only four FQ17W images acquired during the 2014–2015 winter, with a similar acquisition time to the last FOW3 image in the previous winter (Table 1), the second CVice_cover profile in the 2013–2014 winter was used to compare the ice cover variation of the 2014–2015 winter (Figure 5) in an inter-annual assessment