Don,
Many earlier posts address all of the points you attempted to make in your original article. You have not rebutted them, and presumably you accept them.

In your latest post, you slip your interest to uncertainties, which you posit undo much of climate science. It is akin to you deciding not to drive to Sydney because of uncertainties in your arrival time. Uncertainty pervades all aspects of life. In terms of risk analysis, you would seem to go with the 5% option when there is a 95% probability that humans are responsible for most of the warming being experienced today. You seem to demand 100% certainty with regard to climate science, but not when insuring your house or car. Unless there is a 100% certainty of your house catching fire, you will not insure!

With regard to your reference, the author states “Ice cores provide unique contributions to the reconstruction of past climate”, and “ice core records are best known for the information they provide on millennial and longer timescales”. Most of his paper relates to getting greater accuracy with regard to shorter timescale climate and climate forcing reconstructions. That paper in no way supports your position that uncertainties undermine climate science.

You comment that “there’s scads of other stuff about uncertainty” which is lazy way of attempting to make a point. Uncertainty is well covered in the IPCC attributes of “confidence” and “likelihood” that are attached to most IPCC projections.

Unfortunately, I see much of your commentary as a set of strawmen, each with no substance.

Oh - and by the way, snow is ice - forget about your compression bit.

Agronomist, I regard your last remarks about my writing as personal, offensive and ignorant, and I make no further response to you.

Tony 153, I moved to uncertainty because Agronomist offered as conclusive, individual references to ice, sea levels and so on, all of which however come with uncertainty, and all of which have been countered by others. My position is that there is too much uncertainty for any government to have gone down the path of, for example, carbon taxes, which cost everyone and have no discernible effect on temperature. There are dozens of posts on my website that deal with these matters. You can find them by going there and searching. The notion that I should rebut every comment that is made on OLO seems pretty fanciful to me. As I said to Agronomist, OLO is likely to be open to anyone like yourself who can write a thousand-word article that sets out why sceptics like me must be completely wrong.

For obvious reasons, it's not enough just to say 'IPCC!', and leave it at that. The latest IPCC report has over a hundred references to uncertainty, and yet the confidence of the authors that they are right, and that dire warming stares us in the face, is even greater than it was in AR4.

With respect to the Steig paper, which I think is a good one, the second of the quotes you provide from it says that ice core data are best if you want to compare thousand-year periods. Agronomist said that because ice-cores have annual rings it must be possible to measure yearly changes. It is, but the error is really large. That's why ice-core data are best for broad-scale comparisons, which is what I said.

Don, thanks for yor response - I did not expect one.

By the way, you are not a skeptic. Skeptics accept new information and may change their mind as a result. All research scientists are skeptics. You are more in the denier mould - irrespective of information from whatever the source (such as NASA, NOAA, BOM, CSIRO,and hundreds of other science based organisations), your view would not change - as I understand it.

I would think there would be many hundreds of uncertainty estimates in the IPCC reports - annotated as “confidence” and “likelihood” couplets. All science has uncertainties / error bars / confidence&likleihood estimates as part of their results. You have not mentioned any confidence / likelihood couplet from the recent IPCC documents that invalidates the IPCC conclusions. If you could find say 20 such estimates and argue why those values invalidate the science, you might have a logical position to stand on. You could start with one couplet, and move on from there.

No need. The IPCC report contains more than hundred references to uncertainty, and of course lots of error bars. That is not the point, which is that the report accepts again and again that there is uncertainty, that various things are not known, that there are various estimates for climate sensitivity — but remains committed to the view that global warming is occurring, that it is caused by human activity, and that the outlook is dangerous. The evidence for each of those assertions is weak, awkward, convoluted and based, much of it, on models that have not been verified or validated, and did not predict the long cessation of warming.

What is more, the Report does not anywhere, anywhere at all, come to terms with the mismatch between prediction and observations, and set out why it prefers one set of evidence to another, and one set of arguments to others. It does not even recognise that there could be reasoned criticism of its position.

Now — you're the critic. I have read the SPM and much of WG1, and all of AR4 and its SPM, and much of 3AR. Why don't you do some work, and show me where I have got that wrong. Show me the big section that shows why the sceptics are really wrong?

If you will allow me to do so, I will remain an agnostic about the view that human beings have brought about the warming that has occurred, and completely sceptical that carbon taxes and their like are of any virtuous consequence that I can see. An agnostic is always open to new evidence. If you have some, please provide it.

Tony153,

"Don,
By the way, you are not a skeptic. Skeptics accept new information and may change their mind as a result. All research scientists are skeptics. You are more in the denier mould ..."

That seems to be a clear example of projection.

How do you know it isn't you that is the denier? What have you don'e to define what would change your mind?

There is no sign of any rational scepticism in any of what you write. You are simply repeating the mantra of the Climate Cultists. You won't engage in addressing what is relevant for policy analysis. You avoided answering my comment about the facts that are relevant for policy analysis.

So, I'd call you a denier of the policy relevant facts and, since the purpose of the alarmists is to get 'action', the policy relevant facts are all that matters.

I'd urge you to stop calling Don a "denier" and stop being a denier yourself. Address the relevant issues, not the irrelevancies you want to keep yapping about.

Don,
Your comment above: "The evidence for each of those assertions is weak, awkward, convoluted and based, much of it, on models that have not been verified or validated, and did not predict the long cessation of warming." needs to be supported by reference to source information supporting your views.Seeing as you refused my challenge, I will address yours. Check page 18 or WG1AR5. It shows projections without increasing CO2 impacts, projections with CO2 impacts and observed. By the way, please provide verifiable facts, if you can, that warming has ceased. You could try Professor Muller who thought as you did.....

If you cant discuss one uncertainty from AR5 and give reasons why it renders anthropogenic warming invalid, I will assume you cant or wont.

Peter,
As soon as you provide a link to research facts that proves global warming is a hoax, I guarantee that I will read, review, and change my mind if appropriate. Over to you....