I've had a bit of time today as I don't fly out of Stockholm till this afternoon. It's the most day time I've had for 3 months.
So I decided to try and put together the consolidated set of thoughts I've had around these melting events.
First is that continuing increased in greenhouse gasses retain heat in the atmosphere which causes global warming and climate change. Average CO2 is around 2ppm per annum. Up from about 1.5ppm per annum. But the real story is in the accumulated volume of CO2 in the atmosphere
OK so I have to ask "what heat". Well, in reality, there is only one heat source. The heat generated by solar flux in the day time.
OK so I have to go and find the solar output over the satellite period on which we are basing our predictions. Sadly I can't find a chart which shows cycle 24 because it's not finished yet. However we know that the cycle 23-24 low was the lowest for 100 years. We also know that cycle 24 is much lower in solar output than the previous 3 cycles.
Now there is one more element to this picture. So called "natural" variability. The very largest of this is the El nino/La nina pacific SST cycles. I'm willing to bet that this is not variable at all but actually modellable if we just had enough data and knew enough about the heat flows through the oceans.
OK so CO2 is rising. This means that every solar cycle the system becomes more sensitive to solar input. Less sensitive to natural variations and that the heatsinks of the planet have to absorb the trapped heat and try and balance the climate.
So we should see loss of ice on a cyclical basis. With regrowth during the solar low and loss during the solar peaks. Also one point I have noted is that the solar peak and the fall off into the solar low tend to have a cumulative impact. I would expect this with CO2 as the heat generated by the cycle is retained until it finally hits the low and the effect is cumulative.
Then we come to the final part. Variability. So I need to get the SST cycle chart and overlay it on the other two. Where El Nino and solar peak coincide, we should see more loss of ice. Where low and La Nina coincide we should see significant regrowth.
On the opposite side, if a La Nina and a peak coincide we should see less loss and if a low and an El Nino coincide we should see less regrowth or even, in extreme cases, a continuance of the ice loss.
Over all of this, the continuing increase of the CO2 input should create a constant degradation in the ice pack as the heat retained, decade on decade, should continue to impact ice regrowth, especially in winter and in solar lows.
So if I overlay the Ice extent chart, with the solar cycle chart, with the El Nino/La Nina chart, for the satellite record. I should get a correlation of the ice loss results. Granted I have not allowed for changes in Ice Mechanics or for weather changes due to the large increase of heat into the Arctic. But these are relatively new phenomena and data simply does not exist for it.
Apologies, I'm now wizard with images so I simply made them all 50% transparent and saved it out as a PNG. The source images are in the same album which is open if you have the link
It doesn't all map out cleanly, certainly cycle 22 was odd. However the predictions by Hansen Et Al, that we transitioned to a new base in 2,000 and that CO2 mechanics finally took over, looks realistic in terms of ice loss.
OK so looking at that, what should it predict for 2013?
CO2 input in 2012 was almost at record highs and it continues to be high
We are at solar maximum.
El Nino kicked off at the end of 2012.
The ice is thin
Loss is faster than normal in the early part of the season
Weather, so far, is not favouring ice growth.
For 2011/12 the cycle is upside down. (relatively), Low solar, La Nina and high ice loss. 2010 is understandable, I take 2011 and 12 to mean a breakdown in the integrity of the ice.
Personally I’d say all bets are off. But we do have to make some kind of reasoned answer and predict some kind of change.