I want to show you these two trend lines for polar sea ice. It very much reflects what has been experienced. This year we have bounced back to norm and we can expect little this year that compares to last year’s drama. Then last year, almost no one else was watching while today it seems everyone is.
http://nsidc.org/data/seaice_index/n_plot.html
South Pole:
http://nsidc.org/data/seaice_index/s_plot.html
Without question, we have a very clear twenty year negative slope for the north whose explanation is a strict linear surplus of heat annually injected into the Arctic. Last year we saw that the annual melt is now starting to go non linear. This is hugely masked by the annual coverage of the one year ice, but rest assured that the long term ice is now shrinking very fast and will be all gone within the next several years and possibly as soon as 2012. This masking effect kept everyone asleep until submarine survey work in 2000 disclosed that sixty percent of the perennial ice had disappeared.
Now that we have this chart, it appears likely that the majority of the sixty percent loss actually took place during the decade of the nineties, rather than stretched out over the preceding forty years. The apparent rapid decline we are now witnessing fits this scenario very well and is well beyond my most conservative expectations.
An inspection of the current sea ice cover reveals that the extent of the Arctic Sea currently exhibiting one hundred percent ice cover is likely around a mere twenty percent. Even more curious, this concentration is scattered throughout the Arctic as a result of wind concentration. There are no apparent huge zones of embayment that I suspect was the expectation a couple of decades ago. Everything is floating and drifting.
In fact, it is possible to speculate that the right combination of winds could even open up the North Pole for shipping and even all sorts of alternative circumpolar routings. The lesson here though, is that this winter sea ice is ample enough to likely always represent a formidable barrier to actual summer shipping. Oh well, it was a nice idea.
This means that the perennial ice is warming up nicely as it circulates and is certainly disappearing very quickly. All things point to the Arctic in its equivalent of its spring breakup phase. And this season is not demonstrating any reversal of this activity. I think that essentially all long term ice will be gone by 2012. We will still have the annual ice cover and it’s melting to sort out and possibly understand.
Of course, if the sunspot theorists are right this is likely our very last warm Arctic summer for a long time. We are currently between cycles and the onset of sunspots is long overdue. That means that two popularized scientific theories, both based on far too incomplete data bordering on singular coincidence are holding diametrically opposed positions. Do you wonder why wise politicians are trying to keep their heads down?
I suppose that the most amusing scenario would be to see nothing much happen. That means that this modest warming matures and leaves us with a warm period not unlike many before and explained exactly the same way. That would allow both theories to be quietly forgotten while we reorganize industry away from burning fossil fuels anyway.
