Saturday, 20 August 2016

Wunderground on Arctic sea ice collapse

Arctic Sea Ice Collapse 19 July—16 August: Annual Average Volume

By: viddaloo

18 August, 2016

Annual Average Volume (AAV): From the last update at about 14.4 thousand km³ on July 18th, we've lost about 100 km³ from the AAV in 29 days, which was well within the expected timespan of August 11—September 3.

In detail, daily volume went from 9,447 km³ on July 18th to 5,471 km³ on 16th August, compared to 10,710 and 6,885 the year before, giving a relative 
loss of 151 km³. The average decline in AAV over these 29 days has been 3.4 km³/day, which means we've been on average 1,240 km³ lower than last year in daily volume.

The next 100 km³ line is 14.2 and expected on 
September 9—10.

PIOMAS Annual Average Volume will probably go 3rd lowest in October. After that it's hard to say, but maybe 2nd lowest by the end of the year?

At the August 5th PIOMAS update, daily Arctic sea ice volume for July 31st 2016 was 4th lowest for the date, at 7448 km3. This is up from 3rd lowest ever on June 30th, so 2010 has edged ahead, along with 2011 and 2012. In three weeks we'll see if 2016 can take back the lead, after the heavy August melt.

We're now running out of future at the stunning pace of 
103 km³/month. Not in the sense that Arctic sea ice is just melting rapidly, that happens every summer. We're melting a lot more than 103 km³/month, in fact it's closer to 4200 km³/month, but this is a seasonal thing. No, loss of 103 km³/month is the loss of annual average volume of sea ice. If you will a "real" loss of ice, year over year, not just the seasonal melt. This ice is probably never coming back. We'll likely never see 14.3 thousand km³ annual average volume again. Not in our lives. And much less 15 thousand km³. Those days are gone. The next major milestone of the Arctic sea ice collapse is 14 thousand km³ AAV, and expected October 28th—November 11th.An ice–free August?

Now, this may sound a bit silly, as it's 'only math', but the immensely far–reaching consequences of the heavy melt in the Arctic do make me hesitant, for a number of reasons. It's like when does something stop being only math and start being just horrible, terrible, frightening & devastating? Based on my own emotional reactions I believe that time is now.

There's been a lot of talk lately about 'an ice–free Arctic', of which the scientific definition is short of a million km² of sea ice. For volume this roughly translates to below a 1000 km³. Volume is in itself generally regarded as the most reliable parameter of sea ice collapse (if we could only get reliable measurements of the ice volume, which is a significant problem). For this reason I've chosen volume (over extent and area) as my basis for the most accurate estimate possible for when we will have an ice–free Arctic throughout the month of August.

Now, an ice–free August would of course imply ice–free conditions for the whole of September, and probably a fair share of October. Logically, the problem of finding the first year of an ice–free August, can be reduced to finding the first year with no ice on August 1st. Seasonality ensures that the rest of the month will follow if August 1st is ice–free.
What is the significance of an ice–free August?

Well, the first immediate consequence is a massive solar warming of the Arctic Ocean for an entire month in 24 hour midnight sun conditions. In addition, the halocline will collapse due to warming and increased cyclone activity due to the open water, so cloudy weather doesn't help either. The epic warming of the Arctic Ocean will then trigger both record melting of glaciers on Greenland and elsewhere, leading to sea–level rise, and probably even record releases of thawing methane in the sea bed, which will cause further unprecedented warming of the Arctic and the Northern Hemisphere.

All of these catastrophic warming effects are self–reinforcing feedback loops. Meaning it gets hotter faster the hotter it gets. And we have no way of turning down the heat, even if we could get our act together.

So, for a plethora of reasons, but mainly ones related to crop failure, the significance of an ice–free August is that it will mark the end of civilisation as such. It will be nasty, it won't be nice at all. Or to quote video blogger Hambone Littletail: "It's gonna SUCK."
When will we have the first ice–free August?

For this pure math problem I've applied a 2nd order polynomial trendline, which you can see below. And keep in mind the scientific definition mentioned above: Short of a 1000 km³.

Although this statistical estimation of the first full month of August Blue Ocean event should be considered a conservative estimate for the collapse of civilisation, for a number of reasons again, including the huge uncertainties with the ice volume estimates themselves and with the tipping–points of the methane hydrates, it should be emphasised that it's not the end of the world. It's not a full Biosphere collapse and it's not the end of our species, only the end of the set of living arrangements we know as civilisation. But it will mean there's no more food in the store.

This implies you will have to catch or grow the stuff you are going to eat.

Other people may describe the implications far better than I do: 

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