Sir, I at last see a rational response to the mainly media based hysterical rubbish about climate change.

Firstly, this hysteria is generated by the money grovelling grubs of wall street who own the media!

This is their opportunity to charge every human being a tax on the air they breath! (Carbon Tax) And don't think they won't, unless there are people like you exposing those pathetic little creatures that live their entire lives inside a university faculty behind a computer monitor.

They are funded by governments and companies and when they are needed they are 'un-veiled' and they crawl out from under the rock where they exist and proceed to blather dribble to whatever their masters demand.

I salute you sir, you are absolutely correct, this is a cycle, nothing more nothing less!

Ian J Nelson

Ok Viking now answer this

1. Clouds. By what methods are they factored in both high and low, and what science and data are these factors based upon. Or did they just pull the parameters and the theory out of their bums ie made them up.

2. Aerosols.How are these factored in and what is the source data.

3. Freemantle doctor is an example of an extensive regional climatic system that materially alters the weather. It has a huge effect but the regional climate models dont reflect this. Still has not stopped the CSIRO shonks from advising the govt of the dire consequences revealed by their equally shonky climate models. But then if one is just generating consulting revenue to meet internal targets the any old twaddle will do.

4 Which scenarios and why. Is the C02 growth linear and at what rate. Bet they used the most extreme values and methods.

1. Clouds. By what methods are they factored in both high and low, and what science and data are these factors based upon. Or did they just pull the parameters and the theory out of their bums ie made them up.

High cloud (cirrus) absorbs radiation while low cloud reflects radiation to space. These factors are included in global circulation models. Try doing some research of your own instead of dismissing the work of scientists in a childish way.

2. Aerosols.How are these factored in and what is the source data.

Again, try some googling. Different aerosols work in various ways- sulphates assist in cloud formation and are connected to cooling trends, while particulates can work in various ways too, some absorb and reradiate infrared while others have a high albedo and reflect radiation to space.They are measured in various ways including by satellites.

3. Freemantle doctor is an example of an extensive regional climatic system that materially alters the weather. It has a huge effect but the regional climate models dont reflect this etc.

The Fremantle doctor is a seabreeze- a local effect common around the world where differential heating occurs on coasts. Why should that and any other seabreeze be factored into global climate models?

4 Which scenarios and why. Is the C02 growth linear and at what rate. Bet they used the most extreme values and methods.

Linear over what period? Atmospheric CO2 levels have increased and are still increasing. If CO2 level double (compared to present already high levels) the Earth's baseline temp will increase markedly. there are many other greenhouse gases including methane, oxides of nitrogen, and air-conditioning gases (many banned but still present in the atmosphere).

Why dont people read the article more carefully before they post their inane responses. The author is NOT denying global warming, is NOT denying human causes and IS in favour of making changes to reduce greenhouse emissions.
He is also raising a perfectly valid point about the usefulness of mathematical models of complex systems. Their results/predictions should be regarded with considerable scepticism. They MUST be challenged, criticised and tested. Unless there is a vigorous effort to disprove the model then its 'predictions' are all the more suspect. Climatologists SHOULD be welcoming every effort to disprove their work because that is how science works. Any scientist who is irrationally commited to their models to the point that they cannot hear criticism is failing their profession.

As a 'greenie' my first emotive reaction is of course to want to raise scorn on an article that questions the science to do with climate change. It seems stupid to think that 6 billion humans would not have a significant effect on this planet.

But Mark is not denying climate change or that humans affect the climate. He is doing what we should all be doing. Vigorously challenge any scientific conclusions and how they have been derived. Especially when it fits neatly with a hypothesis. That's good for science. Emotional attachment to a certain outcome is OK for us, not so for science.

This issue is too important for us to just relax and think we have this nut cracked. All it takes is get those cars of the road, put some solar panels on our roofs and change those incandescent light bulbs.

The only concern many of us have is that we also should not be sitting around waiting for the science to be beyond reproach before taking any action, because then it could be too late.

Reducing our reliance on fossil fuels is an excellent start for a variety of reasons, not only climate change. Smog and cost being two.

Fair point Yvonne. I would point out that debate in the public sphere is rarely so nuanced, and that criticisms contained in this article can easily add to the general level of ignorance about climate change rather than lessen it.

The IPCC does not know all it needs to know about this, though I believe it knows enough. Not all IPCC's predictions would be accurate and they would know this. But countervailing views by some scientists, in articles not reviewed by their peers, nor published in a recognised journal, are typically given equal weight to those that are. It is a pity the IPCC has stuck its neck out in this fashion; cast doubt on one aspect of the report and the whole lot is fair game for the denial machine.

So for me it comes down to who to believe - The IPCC whose members have been doing this research for 20-odd years, or professional naysayers, hired guns from industry and commerce.

Does the author, or anyone else on this forum, have any comment on the increasing amount anecdotal evidence we are going through a period of rapid change like never before?