The Fast Transition

The peripheral seas of the Arctic Ocean are now virtually ice free in September, they are seasonal sea ice seas.

Need I say more?



It seems I do...

In comments Oale wanted to see this in terms of area, which is fair enough. I've done two graphs, one for area one for extent, both with a plot as percentage of April area and extent.

What is the future of Arctic Sea Ice? Part 2.

In my previous post I discussed the results of model forecasts for Arctic sea ice, and have outlined why I am not convinced by GCM results suggesting long term survival of perennial ice well into this century. What happens if the current trend of sea ice losses continues and will the trend of volume loss continue?

What is the future of Arctic Sea Ice? Part 1.

Recently I blogged about a paper showing the cause of the post 1995 volume decline in PIOMAS, this being the period of greatest and most persistent volume loss. The cause turned out to be self-acceleration of volume loss caused by the ice albedo feedback, as this is such a fundamental process and as the later version of the PIOMAS has proven to be so successful, I am in little doubt that Lindsay & Zhang's hypothesis is correct and that in the 1990s atmospheric impacts on the ice ushered in a period of decline largely driven by the ice albedo feedback.

There is really only one issue I can move on to address now, and that is the future of the sea ice.

Go on, say something outrageous...

I've been having problems with the Tang et al paper about summer mid latitude impacts of sea ice loss. Basically I've been so focused on sea ice that I've a stack of papers I need to re-read on atmospheric impacts, and every time I've tried to 'put pen to paper' regarding Tang et al I find myself needing to re-read several other papers. Unfortunately I've already started to wind down for a Christmas break from work and blogging, so I find that I haven't the motivation.

So I've decided that the final post of 2013 will be a look at percentage open water formation, and a clarification of what I think is a tipping point revealed by the PIOMAS data. Regular readers may already have grasped what I've been getting at before, but now is the time to stop hinting (i.e. 'non-linear') and say exactly what I mean.

EDIT 23/7/14 - after months of consideration and 2014 April data, I have concluded that the effect outlined here will be countered by winter ice growth. More here.