To be fair to Google, crowdsourcing map data does have its pitfalls: OpenStreetMap has to deal with this sort of thing all the time. You have to have something in place to deal with bad-faith edits. None of the edits I’ve made to Google Maps went through without someone reviewing them, so I’m surprised that this could happen. That said, when you need your map updated fast (such as during natural disasters like yesterday’s earthquake in Nepal), it’s hard to beat crowdsourcing.
Whereas the older version of the map showed only that part of the sea ice that permanently covered Arctic waters year round at that time, the new edition uses a 30-year median of September sea-ice extent from 1981 through 2010. September sea ice hit a record low in 2012 and is projected to decline further. The change means there is far more ice shown on the 2015 version of the map than on its predecessor.
The changes can be seen below: the 2006 map is on the left, the 2015 map on the right.
Now as Semeniuk’s piece points out, neither way is wrong. But all maps have a point of view, and it’s naive to think that this change was made in a value-neutral environment: this was the result of a conscious decision. The reason for that decision—that’s what’s interesting.
Dawn’s first colour map of Ceres: map-projected false-colour images of the dwarf planet taken as the spacecraft approached, assembled from images taken through blue, green and infrared filters. (Previously: At Ceres.)