For the period 1989–2014 this observation is interesting. "We have analysed observations of the summer sea ice edge from the ship logbooks of explorers such as

For the period 1989–2014 this observation is interesting. "We have analysed observations of the summer sea ice edge from the ship logbooks of explorers such as Robert Falcon Scott, Ernest Shackleton and their contemporaries during the Heroic Age of Antarctic Exploration (1897–1917), and in this study we compare these to satellite observations from the period 1989–2014, offering insight into the ice conditions of this period, from direct observations, for the first time. This comparison shows that the summer sea ice edge was between 1.0 and 1.7° further north in the Weddell Sea during this period but that ice conditions were surprisingly comparable to the present day in other sectors." http://www.the-cryosphere.net/10/2721/2016/ http://www.the-cryosphere.net/10/2721/2016/ doi:10.5194/tc-10-2721-2016