Part 2
Really?

Quoting the abstract of Huybrechts (2005):

" There exists a point-of-no-return once Greenland ice sheet disintegration has set in beyond which complete removal of the ice sheet becomes irreversible, even if climatic conditions were to revert to present-day conditions. This point may already be reached after 250 years of ice-sheet melting under a medium greenhouse warming scenario"

Basically, should artic temperature increase by 3oC+, it would become difficult for ice to form. Also, as the Greenland ice sheet melts, the exposed surface would decrease in altitude, where it is warmer (due to lapse rate), increasing the speed of melting...

Then there is the possible slow down/ stopping of the gulf stream by an influx of fresh water. I think this is unlikely to occur in the near future, but it has happened in the past and is associated with the "youger dryas" climate event.

5 possible events are discussed in the IPCC, including the mechanics that may cause them.

"Let me spell it out for you folks, this particular sceptic spent most of his career in a job that hinged on his capacity to detect people's BS. I was paid very well for that skill."

Congartualtions! This particular scientist/engineer spent most of his career working in science, a job that hinged on my ability to conduct scientific research and interpret results obtained by others. And I'm still not paid brilliantly, but hey, it sure beats ranting on web forums. Oh... woops

ChrisC, there is a huge difference between saying, "there exists a point beyond which the Ice Sheet cannot maintain itself" etc, and plucking 250 years out of the air and implying, with the very pregnant use of the word "may", that it has been determined by sound science.

If you were a scientist, or any sound managers armpit, you would recognise that such a point can only be described in terms of probabilities. That is, probability of 0.02 of it being 250 years, 0.10 of it being 1000 years, 0.10 of it being 3000 years, etc.

For the record, if current melting was off the top of the Greenland Ice Sheet, which it is not, then the sheet would still be 1473 metres thick in 250 years. This is hardly enough to lower the altitude to a warmer level that would cause a so-called "tipping" and even if it was it would still have the very significant wind-chill effects that can reduce ambient temperatures to minus 50 degrees. In any event, snow is still actually accumulating on top of both the Antarctic and Greenalnd Ice Sheets.

So your little homilies about multiple variables is a bit rich, especially as my earlier posts made specific reference to differing melt rates of water and land based ice, and the fact that I adjusted my raw figure of 14,000 years back to 11,000 to incorporate an identified increase in trend.

But when people start incorporating a mere possibility into their calculations as an assumed fact then, frankly, I am inclined to request a blood test for THC and an MRI scan for either schizophrenia or substance abuse.

Chris O'Neill, there appears to be no direct evidence that Peiser has withdrawn his criticism - apart from Media Watch's assertion that he has. As they don't reproduce the email where he allegedly retracts all of his criticism and I can't find any other reference to it, I think this has to be put in the dubious column.

Peiser does include the Gerhard and Hanson piece in his list of 929 pieces which he says fit Oreskes' search definition. You say it isn't peer reviewed - I can't find any direct evidence of this, but as the document is the report of a committee it appears to me to be about as peer reviewed as you can get, outside of some possible quibble about the publication process.

I've scanned some of the list that Peiser provides of the articles that meet the Oreskes search definitions. She doesn't appear to have provided a list anywhere. In 1994 I come across this one from Hulme and Jones entitled "Global Climate-Change in the instrumental period" which says "Such detailed diagnostic climate information is a necessary, although not sufficient, prerequisite for the detection of global-scale warming which may have occurred due to the enhanced greenhouse effect." This appears to me to be an abstract which is sceptical.

It would appear to me that you, Lambert and Media Watch have all misrepresented Peiser's position. The original criticism is the one he has withdrawn. When pressed for evidence he points to one particular article, but as my scan shows, there are others. He presumably chooses his best example.

Anyway, I'm emailing Peiser to see what his considered position is at the moment. And the thrust of Lambert's and your argument, that Global Warming is established as a scientific "fact" with which no reputable scientist could and does disagree, is still a crock. A fact of which you must be aware.

GrahamY, you are not the slightest bit dispassionate -- you are a passionate supporter of the Liberal party and have run an election campaign for them. The On Line Opinion staff page tries to make you look objective by airbrushing over that part of your career, but you're not. Oh, and thanks for confirming that good science won't get a look in at On Line Opinion until the Liberal Party postion changes.

You accuse the IPCC of "vilifying" Ian Castles, but I'm pretty sure that they never wrote anything about him as vicious as your libel of me. As the editor, you set the tone here and I think that this forum contains lots of flaming and very little reasoned discussion.

Yes, there is lots of debate in the scientific literature -- scientists have a tendency to disagree with each other. But they don't disagree with the consensus -- it's getting warmer and humans are causing it.

Pieser has, in fact, admitted to making mistakes. In my post I provided a link to a direct quote: "I accept that it was a mistake to include the abstract you mentioned (and some other rather ambiguous ones) in my critique of the Oreskes essay.". And yet you accuse me of being "deeply dishonest" for stating this fact.

Gerhard and Hanson is not peer reviwed. If you think it is, you don't know what peer reviewed means. Hulme and Jones is not skeptical of the consensus. Peiser didn't even include it in his original list of 34 abstracts.

The great problem with Andrew Bolt and other climate skeptics is their rejection of science and objectivity, or to put it differently, they see only politics in the constant striving for scientific objectivity.

The scientific community needs some skepticism within its own ranks, however this has been exploited by politics. Results produced by thousands of experiments provides evidence. Any reasonable person would look at that evidence and say let's start looking for ways to reduce or eliminate this pollution problem.

In contrast, skeptics conclude that the CSIRO must have has been highjacked by the Green's Party! That's the political mindset at work blinding out all other considerations. They see it as follows:

Green's bad -> Scientists support Green's -> Scientists bad.

Al Gore provided a clear and consistent message in his film, because politicians are good at that, while scientists usually give nuanced or technical responses putting people to sleep. They are happier in the lab or field, not a press conference.

An Inconvienent Truth was a great film about a real scientific consensus, which the world would be Boltish to ignore.

On #2 Tim Lambert did not know it at the time, but Revelle's "co authorship" of a paper with Singer has a long and dirty history. You can read about it at <a href="http://home.att.net/~espi/Cosmos_myth.html">Justin Lancaster's site</a> and if you don't believe Lancaster you can read the depositions in a SLAPP suit that Fred Singer brought. Suffice it to say that Revelle's participation in writing the article with his name