As I write this, a storm is battering the ice pack on the Pacific side of the Arctic. It's not as huge as the Great Arctic Cyclone of 2012, but it's pretty decent as far as cyclones go, and it's doing its thing in that part of the Arctic where the ice pack looks weakest, but was strongest at the start of the melting season.The timing of this event is perfect for discussing one of the most important aspects of this melting season.
The image on the top right shows the ice age distribution at the start of the melting season, red being the oldest multi-year ice at that time. Due to a very intense high pressure area over the Beaufort Sea at the end of the freezing season, heavy winds drove the ice pack apart there (a so-called cracking event), causing this multi-year ice to become interspersed with very thin ice. That's the dark blue spots between all the red.
During the very first phase of the melting season the Beaufort Sea region witnessed a heat wave causing a lot of this thin ice to melt out. Because the ice pack wasn't pushed back together again, many of the multi-year ice floes were surrounded by warming waters, and ever larger holes within the ice pack on the Pacific side of the Arctic started to form. The animation below shows what happened between week 27 and week 32, or June 29th to August 9th:
Just towards the end of the animation the holes are showing up. Unfortunately these maps aren't updated until the minimum has hit, but we can still get an idea of what happened after August 9th by checking out the sea ice concentration maps provided by the University of Bremen. The following animation shows how the holes separate a so-called 'arm' of multi-year ice from the rest of the ice pack: