August 2014 Warmest on record, globally

[SpontaneousOrder]

Got it thanks. Haven't seen the PDF, but the abstract looks good enough - and if you wnated headlines it would be in the abstract. So, I've extracted what I think is the key bit.



Now, EO, could you find me the bit where PJ said he believed in this possibility and then we're in business.

I get confused when authors reference their own work - but I think this is the original:

Scientific reticence and sea level rise - IOPscience

[Old Greg]

I get confused when authors reference their own work - but I think this is the original:

Scientific reticence and sea level rise - IOPscience

Thanks again. I think this is the clearest statement of his views:

There is enough information now, in my opinion, to make it a near certainty that IPCC BAU climate forcing scenarios would lead to a disastrous multi-meter sea level rise on the century timescale.

If this is the statement EO is referring to, it would be great if he could now point us to the point where PJ agreed with this.

[EternalOptimist]

Thanks again. I think this is the clearest statement of his views:



If this is the statement EO is referring to, it would be great if he could now point us to the point where PJ agreed with this.

To be fair to pj, he probably finds it hard to publicly disagree with the grandfather of the global warming scam. What I dont understand is the idea that the sceptics are trying to paint Hansen as an alarmist and a catastrophist - he does that all by himself

[Old Greg]

To be fair to pj, he probably finds it hard to publicly disagree with the grandfather of the global warming scam. What I dont understand is the idea that the sceptics are trying to paint Hansen as an alarmist and a catastrophist - he does that all by himself

So can you show me where PJ agreed with Hansen's claim?

[EternalOptimist]

So can you show me where PJ agreed with Hansen's claim?

Obviously, he discussed it, and didn't reject it out of hand. Others did. The people who rejected it did not believe in it. People who dont reject it but call it an outlier believe it's a possibility, albeit with a small chance of occurring.

Dont forget, Hansen predicted 5m as a business as usual scenario. We all know that CO2 levels have risen a lot since then, so the 5m should be going up.
How many metres are you predicting OG ? or would you go with my 150mm prediction ?

[pjclarke]

The point of Hansen's 'Reticence' paper is not an attempt at an accurate forecast, indeed it states

'The nonlinearity of the ice sheet problem makes it impossible to accurately predict the sea level change on a specific date'

The point he is making is that none of the estimates of sea level rise deal well with ice sheet break up - and if you examine the IPCC reports they are quite explicit on this point. Hansen's view, backed up with references, is that the breakup is likely to be non-linear and so

'Under BAU forcing in the 21st century, the sea level rise surely will be dominated by a third term: (3) ice sheet disintegration. This third term was small until the past few years, but it is has at least doubled in the past decade and is now close to 1 mm/year, based on the gravity satellite measurements discussed above. As a quantitative example, let us say that the ice sheet contribution is 1 cm for the decade 2005–15 and that it doubles each decade until the West Antarctic ice sheet is largely depleted. That time constant yields a sea level rise of the order of 5 m this century. Of course I cannot prove that my choice of a ten-year doubling time for nonlinear response is accurate, but I am confident that it provides a far better estimate than a linear response for the ice sheet component of sea level rise under BAU forcing.

(My bold). So he never actually predicted a 5m rise, he gave this as an example of one non-linear progression pathway. An outlier on an outlier. The closest he comes in this paper is

However, as a physicist, I find it almost inconceivable that BAU climate change would not yield a sea level change of the order of meters on the century timescale.

But of course, this argument gets stripped of its nuance and becomes 'Hansen predicted a 5m rise in Sea level', and this is contrasted with the few mm a year we are getting now to try and paint him as an alarmist....

[d000hg]

arctic ice is up

antarctic ice is up

wasn't the arctic supposed to be ice free this year ?

Must be all that August heat helping the ice formations

I would not be suprised if PJ came along and said that he predicted this all along, and that increased ice was indeed caused by global warming

Well that is what happens in your freezer if you don't shut the door properly... warm moist air gets in and the next thing you know, the whole things full of ice

[EternalOptimist]

The argument gets stripped to that because thats what made the headlines. BIG headlines
and thats what he wanted.
Just to put OG mind at rest (and mine) do you believe there is any chance of that 5m rise by the end of the century ?

[Old Greg]

Obviously, he discussed it, and didn't reject it out of hand. Others did. The people who rejected it did not believe in it. People who dont reject it but call it an outlier believe it's a possibility, albeit with a small chance of occurring.

And can you how me where PJ said this?

Dont forget, Hansen predicted 5m as a business as usual scenario. We all know that CO2 levels have risen a lot since then, so the 5m should be going up.
How many metres are you predicting OG ? or would you go with my 150mm prediction ?

Unlike you, I lack the data, models and education to make a prediction, but if someone wants to share what the scientific consensus is, then I will probably see that as the most likely scenario.

[BrilloPad]

Just to put OG mind at rest (and mine) do you believe there is any chance of that 5m rise by the end of the century ?

Who cares. I would be 137 by then.

I think buying a house in LLandudno (basically a flood plain) was a mistake. Snowdon would have been better.