https://www.cnet.com/news/nasa-spacecraft-spots-striking-shift-in-mars-ice-cap/

The earlier view is bright and blue with what appears to be plenty of frost cover. The 2019 image of the same spot shows the frost abating as a set of darker pits have grown and merged into each other, resembling a weird patch of amoebas.

The MRO HiRise camera team at the University of Arizona released a video Tuesday exploring the transformation.