The decline of the Arctic sea ice is a perennial favourite among our millennarian friends, with "Death Spiral" being favoured buzzwords used to keep the subject in the front of people's minds. Here's an example from shouty* (official) skeptic Phil Plait.
However, new light is thrown on the subject by a paper in Geophysical Research Letters (H/T Hockey Schtick) which finds strong covariability between sea ice levels and the Atlantic Multidecadal Oscillation. In other words a significant chunk of the variability seems to be entirely natural.
It's life, Jim, and just as we know it.
*Is it just me, or is everyone involved in the Skeptics Society incapable of speaking without shouting?