Shame that these two didn't get a Noble Prize.

Scott, Menlo, USA

So, even though temperatures haven't risen since 1998, that CO2 follows climate change, that over 31,000 scientists have disagreed with the popular conclusion and that the solar cycle is the main factor in all of this, people still want to cling to the fantasy-land of carbon taxes fixing everthing!

matthew, Newcastle, UK

After a fairly mild winter, summer's blazing desert heat was a month late, this year, just arriving now, instead of the customary mid-May.

David W. Anderson, Fallon NV 89406, USA

Do we know how temperatures vary on the moon? It presumbly experiences the same variations of warming due to solar fluctuations as does the Earth. But no complcating effects of man-made pollutants. No atmosphere, of cousre, but still might give an interestine comparison. Anyone know?

Jon Kirby, Coventry, UK

In response to Jade
We cannot "reduce emissions and adopt a better lifestyle." Not realistic, and a dangerous attitude - people in Africa could benefit from having modern ammenities like carbon based electricity(wind and solar are not enough) .Lives are in the balance. I bet YOU have a fridge.

Michael Foober, Boston, USA

And just to underline this, 2008 the missing solar cycle 24 seems to be having an immediate impact on Northern Hemisphere global temps. USA, China, Middle East - coldest winters for many years and coolest spiring and early summer in the UK. Coldest Australian 'summer' - just a hiccup!

Jon Wharton, Sheffield,

The moment a theory becomes orthodoxy you can be sure it is wrong. I grew up in a world where we would run out of oil in 1973,then 1976 then 1981 and we have more oil now than then. Climate change is the latest in a long run of scare stories -remember the millions to die from SARS or Mad Cow disease

Ian Comley, Horsham, United Kingdom

Unfortunately this is a simplified look at how climate works. Of course there is solar forcing and that has predominated in the past, but we have pumped so much CO2 into the atmosphere that we have driven the system into situation closer to 55 million years ago when rapid heating occurred (PETM)

J Banton, Cambridge,

Great article. The whole debate will be forgotten in 5 years once the media has milked it for all its worth.

D Smith, London,

i think global warming is really bad because lots of the glaciers are melting.

jhfh, Dallas,TX,

i'm slightly sat on the fence about this because yes the climate is going up but if you look at every single graph the temperature will go up and come back downso considering this the temperature will go back down but it may result in a very bad ice age because of the hight of the temperature.

Alex Gocher, Honiton, England

Mean temperature on our planet continues to drop at 0.7C/year, a mean drop of 14C would constitute an 'ice age'.

The other planets in our system will also be following the same trends, governed by our Suns' activities.

But, lets forget science,listen to the barmy brigade on 'global warming'lol

Steve Aynsley, Blyth, Northumberland

You cannot put a tax on the planets natural cycle being the cause of global warming!

John Robinson, Atherton Manchester, UK

CO2 hysteria is a cover-up for chemical polution - dioxins etc - that have a lethal effect on all life. The chemical industries must be overjoyed by the global warming smokesceen. Of course there is a link, but chemical polution is the far more serious danger. Reflect that human society can cope with temps -10c to 40c

michawel clarke, cambridege, uk

I have been trying to publish my work (quietly beneath our feet) for some years now without success. They call it science!

Roy Masters, Fakenham, UK

I agree totally with Troy. The key thing is - Svensmark's theory is better than the CO2 theory. But that is no excuse to pollute our planet.

If humans really want to survive until the next great supernova event, or a gamma ray burst, or comet, meteoroid, or supervolcano event, then we must learn to live in harmony with our ecosystem.

Unless we do so, we will run out of resources, like many other plague species, and die off.

J Clarkson, Camborne, Cornwall

According to Cara
"Oil companies have set up and funded countless think tanks and PR agencies (which often have scientific sounding name to make them sound like legitimate research institutions)"
The first and foremost ilegitamate research institution is the IPPC. They do not do research, they do not modify their 'findings' based on current research, and they are a body of poiticians - not scientists.

Joe Scott, Yates, USA

In the end, I feel it will boil down to simply man's choice of living with a monetary based system as opposed to a system based on need. When profit takes presidence over need, which it does (look at our current housing market), then resources are extracted as fast as possible and population grows as fast as possible. If this were not true, then why the fast pace of life. If mans mind set was that of need as opposed to greed, then resource harvest and population growth would be of a complete different nature. I do realize man could never accomplish this way of thinking, but you should at least realize that there are better approaches to dominating a planet and understanding how a planet provides for its inhabitants. (By the way, I'm not a communist) Clean air and water sure is nice, what is it worth from a monetary perspective?

Dan Warden, Crescent City, California

These arguments are all irrelevant. It angers me so much when people argue about whether global warming is real or not , because it shouldn't matter one way or the other. Even if by polluting we don't raise Earth's temerature, that shouldn't just be a free pass to pollute. No matter what the consequences of polluting may be, we shouldn't pollute simply for the fact that we have only the Earth to live on and nowhere else. The Earth provides us with everything to live, resources to build, food to eat,and it is the birthplace of all men. We should only treat the Earth in the same way it has treated us, with respect. If the planet doesn't get hotter because of our pollution, then great, but we still shouldn't trash it. If we take this approach, then it won't matter whether or not global warming exists because we will already be acting responsibly with our planet, which as of now is the only one our species owns.

Troy, Orlando, Florida

"Oil companies have set up and funded countless think tanks and PR agencies (which often have scientific sounding name to make them sound like legitimate research institutions) which have paid thousands of people money to deny man made climate change. For years the White House censored climate change research, and persecuted scientists who dared speak out about the dangers of manmade climate."
Cara...compare what individuals actually receive. Al Gore gets $700,000 dollars each time he presents his one-sided presentation. "Countless think tanks"? A bit of hyperbole don't you think?

John Bryant, Anchorage, Alaska

To Cara in York, your ignorance of American politics is surpassed only by your ignorance of science.

85% of the climate grant money awarded during the George Bush presidency has gone to universities and scientists who believed that the current, albeit slight, warm up is being caused by antropogenic activities.

There have been some, NASA "scientist" James Hanson to name one, who have said that President Bush has limited his views from being published. Mr. Hanson has been heard more than any other "scientist" in America due to the meida coverage of his views.

Yes, we are a carbon energy driven society. We do need to find other energy sources, nuclear for one. But to point the blame for all the issues just to us in America is foolish.

I read where Prince Charles has called me ignorant. I am part of the solution, where Charles behaves like our last president. You remember Bill Clinton.

William Vanderbrink, La Porte, USA/Texas

It is a complete nonsense that scientists who dissent from the man made climate change theory ‘are greeted with impediments to their research careers’. In fact the very contrary is true – publishing any material that challenges this hypothesis is the quickest way to make a fast buck in science. Following an IPPC report last year ExxonMobil offered £10,000 to any scientist who would publish anything hinting that the findings of the report were wrong. This is just the tip of the iceberg. Over the past few decades, climate change denial has developed into a multi-million dollar PR industry. Oil companies have set up and funded countless think tanks and PR agencies (which often have scientific sounding name to make them sound like legitimate research institutions) which have paid thousands of people money to deny man made climate change. For years the White House censored climate change research, and persecuted scientists who dared speak out about the dangers of manmade climate.

Cara, York, UK

why not have the benefit of the doubt and reduce emissions, whilst also adopting a better lifestyle?

Jade Pilling, london,

First of all I apologize for my english, but I hope you understand me.
Second I want to say hello to the reader.
During 1971, when i was a student in Arcetri,a seminar on the increasing of solar UV was held and the claimed cause was the Concorde airplane. In the same period Arcetri's team had measurements on the White Mount and no growth was measured.
When some year later they realized that Concord was not a concurrent for american's air companies, the focus was moved on other sources.
During the TV political shows nobody accept to put on the table how data are collected, and any discussion is based on false information.
Here in Italy something similar happened with ne Nuclear Centrals, to avoid their building or to favorite the conversion (TO CARBON!!!) of the existing ones. Now some politic that was contra say to be pro, but is clear that there are other interests in.
I wonder how someone can be so stupid to put himself over the Nature.

Cesare Licheri, Pistoia, Italy

Al Gore will always be known for two inventions: The internet and global warming.

Dewey Longuski, Mason, Michigan/ USA

I am reading the book "The Chilling Stars" and have always wondered what caused climate change in previous centuries.
This book is clearly attempting to answer these questions.

We are led to believe by our political masters that global warming is a new and man made phenomina. We shall no doubt be taxed to support their argument but this won't alter the fact that it has occurred in previous centuries when it could not possibly have been man made.

We should be asking why our governments are not looking for other reasons besides the CO2 argument. The answer may be all too obvious.

Noel Dobson, York, N.Yorkshire GB

I heard somewhere about measurements carried out by space probes or satellites; these observations state that in the atmosphere of some planet, whose heat is held by greenhouse effect (Venus, Jupiter, Uranus...), rising of lowering of temperature are recorded in coincidence with the ones recorded on the Heart. This effect is measured (non guessed) over data collected during a period of time, and it seems a fact; that looks as to be a final strike against the theory of man-made global warming.
Moreover, volcanoes emits in short times carbon dioxide amounts that overcome the quantity from human activities. And carbon dioxide is not the only or the strongest greenhouse gas; methane and water vapour are by far more important, and they are very little (say, not at all) under human control.
But there is one (and a strong one) reason to hide this all: fear of global warming is a powerful support to research for energy saving technologies, and to get over fossil fuels.

Michelangelo Coca, Muro Lucano (PZ), Italy

People do not work if they are not scared.
I like the theory of non-man-made Heart warming; I think that's a more scientifically correct position. But I will not tell anyone.

Michelangelo Coca, Muro Lucano (PZ), Italy

I think the point of this article is to express that our understanding of climate change and the factors that affect this are still open for much examination. By insisting on a concesus that the effects of Greehouse gases, in particular anthropogenic GHG's, are causing global warming/ climate change, then this is preventing true scientific practice in looking at other aspects that may have an affect to gain a better understanding!!

IF the truth is that anthropgenic GHG's play only a small part incliamte change and that reducing our emissions will have little effect, surely the vast sums of money spent on this would have been better spent funding further reseacrh for better understanding of the Earth's climate, also for looking at ways of off-setting the effects of global warming on our society.

Either way "Freedom of Speech" should not be quelled especially within the scientific community, the 'whackiest' ideas often result in the biggest leaps forward in understanding.

Liam, Northampton, UK

In reading a "Earth's Climate: Past and Future" by William F. Ruddiman (2001, but a new version is upcoming), a useful and scientific text, I find a no contradiction between global warming caused primarily by CO2 emissions and an enlarging East Antarctic ice sheet. Ruddiman states that, "Today, this frigid ice sheet is starved for snow, and the somewhat warmer temperatures of a 2xCO2 world might supply more snow for faster and thicker annual accumulations of ice" (p. 434).

If there's one thing I've learned from reading this entire text, along with numerous online and print articles, it is that Earth's climate is a hugely complex system, and it cannot be accurately thought of as a system with only a few consistent controls. When the words "global warming" are used, it implies that the temperature increases all over the world. But there are multitudes of other effects, as well as cooling in regions, and the argument can never be reduced to the idea that warming always means melting.

Pat Kujawa, Butte, Montana, USA

May I refer to Mr Kemmish of Biggleswade? I agree with him that a low consumption lifestyle is precisely what is needed. I suspect Mr Calder would not deny it. As I read Mr Calder he is not propounding a profligate lifestyle.

Indeed as Mr. Kemmish so rightly infers, most systems are more sensitive to initial inputs, and more chaotic than most suppose. Is it not the case though, that Mr Calder is proposing being scientifically sure of your ground before investing vast resources to a project? And is it not equally true that our erstwhile and current western profligacy is exactly what all our politicians are encouraging: every pronouncement they make when not on the subject of "global warming", is one based on assumptions of - and the desire for - continued economic expansion.

It seems to me to be a simple lie, that you can have that AND cut emissions.

Bob Valentine Trueman, Llanfair Caereinion, Powys

Brilliant scientists are usually egocentrical. Egocentrism can lead to a lot of hasty decsions, like promoting C02 based Global Warming as proven. I have detected for about the last 15 years a shifting scehdule of seasons, however the seasons length and temperatures have not been changing dramatically or at all. If Global Warming is just part of Earth's natural cycle, who is to say this is not a way for the Earth to produce more oxygen to combat " high C02 levels." If the Earth has been around for billions of years and has endured cosmic meteorite blasts and other disasters that produce much hig her pollution, than it is just silly to pretend that in the two hundred or so years we have been industrialized, we are able to have a global impact that not even the universe could match for billions of years.

Todd, La P, America

Calder is seemingly one of the few ethical men of science left in the self imposed pit of despair academia has dug for itself in the hypothesis of CO2 driven global warming. And The Times deserves at least a mention in dispatches.

Fortunately the general lay public in Britain can smell spin and propaganda a mile off. Even the BBC has at last woken up to the fact that ordinary sane people are increasingly demanding intelligent debate, even if most of our formerly hallowed and respected institutions editors and broadcasters seem bent on trying their utmost to stifle it. Understandable from politicians, after all they created the IPCC, but why is there such mania for censorship?

What do they fear, one may ask.

Dick Jaworski, Rye, East Sussex

The world is getting a lot lot warmer. The climate is changing, seasons etc & we are in solar minimum at the moment? Just wait until 2010-2012 when the solar flares next get going in solar maximum! I just love all the sceptism amidst all the evidence around us. Even simpletons can see that worldwide, the climate is weird at the moment. It will get worse though & I just hope your sceptism will help you get through it he he!

Sylvie LG Pollard, Luton, UK

I think the scientific evidence for these alternative theories mentioned in the article is no greater than the small amount of evidence that supports the current 'greenhouse gas' theory.
What I find most worrying, is that current global warming campaigns have distracted from current conservation in practice.

At present, conservation measures are severely lacking. What's the point of preventing climate change to save our future environments when we arepractically unable to save our environment in the current climate? (during a walk through a local nature reserve I was surprised to find the most common flower species was oil seed rape!).

In the carboniferous period (300mya), CO2 levels were at 70% of the atmosphere and plant and animal life flourished. Rather than pretend we know a lot more about climate change than we do (politicians, scientists and journalists (including Nigel Calder) are all guilty of this), surely we should invest more in the conservation science that works?

Ben, Oxford, UK

I always enjoy reading articles by authors trying to plug their new books, because they refuse to cite their sources and leave so many questions hanging, that the reader just has to go out and buy their book to get the answers to the aforementioned questions. If Nigel Calder were a serious scientist, all his citations would be listed, so one could check his reasoning.

Aidan Luce, Norwich, UK

In my veiw, global warming is a myth, i cant say for sertain but i have strong belife that it is. I am getting taught in my geography class how 2 stop climate change and how terrible it is but they have given me any good evidence to prove the thery of global warming, so i am not convinced. i an only 13 years of age but i believe i am intited 2 my veiw. read 'state of fear' by Michael crichton its all about the myth of global warming.

holly, london, uk

I have yet to see any research on the difference in efficiency in o2 production between managed and unmanaged forests. If you understand the process of o2 production in daylight ,( chlorophl action) vs the release of co2 in nightime respiration of plants, it would seem obvious that a young healthy stand will produce more o2 and loose less co2 than and old decadent forest ith a mass of dead and dying vegetation. Yet I don't see any reference to the opportunity of changing and improving the cycle by improved management of our forests. Since anthropogenic co2 is a small percentage of the totoal co2 in biological cycles, doen't it make sense to improve the way the ecosystems utilize that cycle?

Robert , Port Townsend, Jefferson/ WA

Candice from Wildwood US, I think your statement speaks volumes about your ability to distinguish between hype and reality.

John, Plano, Texas USA

Wait I know how to fix man made global warming... all americans need to give up there individual rights and install a socialist goverment.

Why didn't al gore just say that.

Man made global warming is a political issue not sience.
solutions for global warming.
1. Raise taxes
2. Controll the Free market.
3. Pass laws that take water and property rights and transfer to goverment.
4. discredit political enimies as "flat-earth minded idiots"
5. convice people they are being the good guys for striping the constituion and bill of rights.
6. gather all power into a centeral goverment.

Hmm man made grobal warming cost our freedom and individual rights. Yes i think condidering the time frame involved in change that i would like 100% on wheather or not it was real. Don't you?

Jon L, Pine City, MN

what i have to say is well then why is all the all the ice melting and what about the polar bears???? you think there dyeing for no reason at all ,well have you thought that the world is worming up and there homes are melting how would you feel if i took the ground out from under your feet and made you swim until you died because you couldn't rest at all??? have you noticed that over memorial day the haze was almost at a RED because of all the cars going through. today was an absaulutely beautiful day but we dont get many of those.....

candice, wildwood, United States

The issue of cooling over the East Antarctic ice sheet (rather than East Antarctica) which extends into the centre of the continent does apparently have an explanation. Which is that the circumpolar winds (the polar vortex) have strengthened over the past 30 years (why is not well understood, but it might be due to stratospheric cooling thanks to the reduced ozone over the South Pole).
The stronger winds prevent warm air from reaching the interior. However, the Antarctic Peninsula is definitely warming, and even though the cooling over the East Antarctic ice sheet means more snow and thicker ice, the edges of the continent are melting with increasing speed. The Larsen B ice shelf collapse underlines this. We don't know what the future holds exactly down at the bottom of the world, (or anywhere else) but if the ozone recovers, expectations are that the cooling trend will also "recover", and warming will return.
Nigel, please explain...

Fred, Auckland, New Zealand

As a non-climate scientist who has recently taken a keen interest in the debate, what strikes me most is the cyclic nature of climate. We need to determine just how much of what we see is due to natural cyclic variation and how much is man-made. And very few climate scientists seem to be looking at the effect of natural cycles.

peter ruthven, melbourne, australia

There is absoutely NO SCIENTIFIC evidence to support the idiotic notion that mankind can influence the Earth's climate. For sure, there is much "Opinion", generally couched in "If'" , "It is possible", and "If that should occur" rhetoric . And since there is no Lesser Spotted Fleabag for the former tree huggers to save, they have all jumped on this new Global Warming bandwagon and act as though there was something mankind could do to fix it. Al Gore's "Inconvenient Truth" did indeed contain some inconvenient truths. One of them, the fact that global warming PRECEEDS increased levels of carbon based particurates seems to have escaped his notice. Science is done by scientists, not tree huggers, not political hacks, and is never, ever, based on opinion. Science is based upon ideas which after global peer study may or may not result in a generally accepted theory. And right now, the sad truth is that those who want to conduct REAL science don't get funded. And that is a very sad truth.

Jim, Norwich,

Peak oil anyone? No trees left to take up the Co2, all the climate change skeptics said it was OK to cut them down. Air pollution anyone? Can't breathe but that's got nothing to do with climate change! Want some water in thum thar hills? None left, the glaciers have all melted and snow doesn't fall anymore. Any species left? Nup, not even homo sapiens! Whatever you want to call it - global warming, climate change or just simply air pollution. It is anthropogenic effects on the planet! We can change it! But only if there's money in it! (sic)!!!!

Lish, Melbourne, Australia

When the evidence is all around us, why do we keep denying?
As long as I can remember, 38 degrees C scared us like hell(i'm from Romania) and we had few victims through years claimed by heat; this year we have 43C(today was 41 I guess) and over 20 victims in 2 weeks. And another
thing: we have have now 2 weeks of 40+, without any wind or rain. As far as I know(i'm 30 years old), this never happened here. So, should I believe that global warming is a bluff, as you say, or should trust my senses?
I know that panic it' not good, but in the end, denial is a far worse enemy than panic.
Panic may cause reaction, but denial .........

adi popescu, bucharest, romania

Isn't there a confusion between the use of the terms of climate change and global warming. If we are talking about global warming then the model for East Antartica creates room for doubt but if we are talking about climate change then East Antartic's cooling is more eveidence for climate change so define your terms.
As for all the issues surrounding climate change, maybe we should define it as abnormal climate change because the climate has always varied, all the arguements for and against boil down to one thing and I can only use an analogy to make this point:
Imagine you went to your doctor and he said that after the tests he's done he was 70% sure you had cancer but because he wasn't 100% sure he wasn't going to do anything until he was. You would think he was crazy.
So it's our choice; are we going to wait for the 100% or do something that in the long run benefits us all?

Nicky, Girona, Spain

I do not disagree with the main point of your thesis that it is up to individuals on the watch tower to be warry of scientific hubris. But, I do have a few qualms to points you use to make this claim. Science requires statistical consistency. Just because you can site a few specific examples that differ from the general trend does not mean the general trend is wrong.

As research funding and resources are limited, it is best to focus that research on the general trends while allocating additional funds to fringe theories in the proportion that divergent cases are evident.

If the Sun has this much direct control over the climate then we do not have any control over such things at the current moment in time. But, if greenhouse gases do have an effect, then we do have some control over at least one factor involved. Thus, it is good that we should continue to focus on what we can control in greater proportion than those things completely out of our control.

Christopher Lyman, Rochester, USA / New York

The only thing that controls the climate in this world, is the God who created the world. Going on tangents to "save the world" is a silly notion indeed. People are always looking for a cause. If the government and all these celebrities would dedicate the same amount of time and money to ending hunger and stop using children in their commercials about "saving the Polar Bears sea ice" this world would be a better place. Even the children's movie "Happy Feet" was politically charged and aimed at the under 12 audience. The poor penguins that the humans are killing off due to global warming. Complete rubbish.

Robin Argyle, Durant, USA/Oklahoma

Lets understand what is motivating the vast expense of scientic study, climate change groups, 1000's of bureaucrats in office, an ex vice president pilgramage to the world and a ultimate message of "catastrophy". The main reason is simply - money, control of the deminishing oil and natural resources and fear of what will happen, namely wars. Climate change is to control by fear the masses.
I have no problem with a govermentally policy and dictate for recycling, environmental awarness and saving energy but i refuse to allow scaremongering tactics and blame mentally to direct my thoughts.

steve jackson, london, england

The thing is, it certainly isn't going to harm the planet to cut down on greenhouse emissions and find alternatives to fossil fuels. In the meantime we can work out just how much harm they are doing. But if we stop the current trend to watch our emissions until we are 100% sure about the cause of global warming (which, let's face it, isn't going to happen - there will always be dissenters to every theory), then find out that we are responsible, it will definitely be too late to do anything.

Kate, London, UK

why should we believe what the government are saying?
they did not themselves at first believe that climate change was happening. I am just annoyed how they think and others think that switching off some plug switches will stop the climate change. Maybe i am wrong but putting taxes on flights to apparently stop humans destroying the earth will become an advantage for the upper classes. Where has equality gone?
I would also like to say this article will help with my project on climate change.
I think other explanations should be looked into more detail, researched and put forward.

Mahnaz, hall green, england

We had scientists with the ABC TV in Australia trying to ban a BBC TV documentary presenting a point of view differing from the human self flagellating perspective - they definately belong to the "flat earth brigade". I wonder how those fools that blame Homo sapiens for their perceived "ills of the earth" would explain the rising sea levels that isolated Australia's off-shore islands that were part of the mainland 6000 years ago, well before the technological age?

Brian Bush, Stoneville, WA, Australia

If one pretends that co2 augments temperature one should no only base oneselves on observation but, I should think, on some experiments also?
So, I ask what experiments have been done to confirm that co2 augments temperature? And how can this be extrapolated and been in agreement with the global warming measured?
A search on the internet did not give me any answers.

naudts, brussels, belgium

What is needed is a Bill Gates of the sciences. Someone with the tax dollars, to invest time and research, with enough clout to counter the AGW insanity.

Excellent article, from the always cogent and clear thinking Calder.

Craig Hawkins, Solihull, England

Thank you for at least bringing some balance to the argument.

David, Cmbridge, UK

Thank you Nigel Calder for reintroducing some scientific, objective based data into the Great Goreaphobia climate hysteria. Former vice-president Gore has a history for the dramatic and patronization of non-politicals. His subjectiveness is the rule of his analysis which is quite understandable when you view his background. Politics, journalism and law. Which are usually disassociated from scientific disciplines and logical, objective analysis. I smell politics and major monies at work in the root of Gore's fluff. With the U.S. media so obviously liberal as to not even hint at the possibilty that any disagreement within the scientific community could possibly exist. Why who would possibly suggest credibilty issues loom large with Gore's postulate? I can only hope that enough counter supporting evidence is introduced before Gore has cost the American public trillions due to his scam.

J.M.Willey, Bridgeville,

Thank you Nigel, for being a beacon on truth on this issue. Prior to this year, I had a general belief that AGW was an issue that man had to deal with. Ironically, it was only after seeing Al Gore’s movie, in which the facts as presented did just not make sense, that I spent some time researching what was really going on. With the power of the Internet to let all sides express their viewpoints, it did not take me long to realize that AGW was likely going to be the biggest red herring in human history!!!! It ceases to amaze me how society has blindly jumped on the AGW bandwagon.

I guess time will be the arbiter of truth. As you point out, temperatures have NOT been increasing as of late, and given the latest NOAA solar forecast, are likely to remain steady or even decline over the next few years. Eventually the general public can’t fail to to notice this and it will be quite enjoyable waving to those who powered the AGW bandwagon, as they stand in line looking for work!!!

Mark, Toronto, Canada

Yet another pointless message thread :>

Cheers, Mr. Calder, I identify with this article.

Phil, New York City, New York, United States of America

The experiment that "hints we are wrong on climate change" was a laboratory study on how ions may influence the formation of tiny aerosol particles. The results are miles away from being evidence that greenhouse gases have a much smaller effect on climate than previously thought. The formation of cloud droplets was not investigated, and they are not likely to be strongly affected by the formation of the tiny aerosol particles. Extrapolation of these lab results to the global atmosphere is another issue. Compared to this single lab experiment, there are mountains of evidence from many different kinds of measurements and analyses that confirm the important role that greenhouse gases play in the global climate.
If we were to burn all available fossil fuels, the world would look very different, with sea level rise possibly tens of metres higher than they are today. Close to a billion people live in coastal areas that would be affected by such a sea level rise.

Darrel, Toronto, Canada

A useful chart

one part per hundred= 1.000 = 1%
one part per million = 0.0001 = 0.0001%

One part per million is the annual increase in CO2 which may or may not be mostly due to man's AGW contribution.

If the CO2 increase of 150 parts permillion over the last 150 years (.015%) has caused a .5 deg. increase, we have time.

no worries.

ventana, new york,

are we really the cause of the earth warming up? are we really the trying to stop it? this situation has only arised recently and the govement are suporting new ideas to help. however is it really posible that our earth might die if people are doing thier bit then why still is global warming an major issue

layla, hull,

Everyone seems to forget that all of the coal, oil and gas that we are burning was at one time CO2 in the atmosphere. Prehistoric plants converted that CO2 in to starch and oxygen. They died and were buried, after millions of years becoming these hydrocarbon deposits. So in reality by using these deposits all we are doing is returning the CO2 back into the atmosphere to start the cycle again. Let's quit worrying about CO2 ( A naturally occurring substance ) and get back to fixing the real pollution problems we seem to have forgotten in all of this global warming hoopla.

Matthew Bergin, Hamilton, Ontario, Canada

Am i right in thinking that 0.4% of global warming is due to humanity or is it a different figure. Will someone please help as i have been having a big argument with my family about it and we want it settled!

christopher, chard,somerset, england

2 questions from a person in the 'developing' world:

1. Which countries have the bulk of the coal, oil and other carbon-based fuel resources - the 'developing' or the 'developed'?
2. Which countries have the (renewable) energy technologies - wind, nuclear, etc - that will have to replace carbon fuels as the developing world's only other options for energy?

It's hard to see the science when it's buried under so much politics!

Prashant, Mumbai, INDIA

Finally some sense. It makes no scientific sense that man and his miniscule amount of CO2 and miniscule amount of Watts of power being added to the system affect the climate as we have seen. Especially when the data do not match for greenhouse gas and CO2 concentrations and the temperature curves, but lo-and-behold, the Suns irradiance and activity graphs match VERY WELL with the climate changes throuhout history. To paraphrase james Carville -- ITS THE SUN, STUPID. Many many scientists are skeptical of the whole greenhouse gas crap but it has become Politcally Incorrect to talk against it. Even when there is no real scientific data to support it. The only "data" is data generated in virtual worlds that are programmed to follow various models with the biases of the creators. But they cannot point to any real world data that supports their models. Again, the earth may be getting warmer, but man's contribution to that is minimal if existant at all. ITS THE SUN, STUPID.

Chad, S Jordan, UTA USA

Good gawd you Limies are just as ignorant as most Americans! Two thirds of the red-herring-laden misinformed opinions on this list strike me as coming from the ilk that considers the lunar landings to be faked and "The Flintstones" to be a documentary!

Here's a sampling of the specious arguments so far: 1) local examples of cooling disprove a global trend of warming; 2) increases in minority gases in the atmosphere can't amount to anything, because, well, they're a minority; 3) global warming must be a crock b/c 25 years ago people were talking about global cooling; 4) fossil-fuel combustion must be benign and/or inconsequential b/c it amounts to the same thing as us breathing and volcanoes erupting; 5) the sharply rising CO2 levels over the past 100 years [fact] are the RESULT of warming [which, curiously, seems not to have begun until at most 50 y.a.], not the CAUSE... blah, blah, blah Yeah, 6.6 billion humans and their cars, factories, cows, etc. have NO EFFECT whatsoever!

Brad, Georgia, USA

"GW - what are we going to do about it?" Neither taxes nor carbon credits will make any difference to carbon levels. But, fossil fuels are a finite resource, so we are going to have to use other sources of fuel. The stumbling block to innovation in this area is the immense research costs involved, and the lack of interested parties. Democracy fails us on this point, because it promotes government actions that can be implemented during the term in power. We need a new parliamentary instrument, to bind future governments to adhere to an agreed set of principles. Our job is to suggest those principles to our governments, and get them started on innovations that will improve the world. My own favourites: No internal combustion engines on our roads. No carbon-based power generation. No artificial packaging materials. No air freighted foodstuffs that could be grown in the destination country. By 2050, no argument. OK, they can pay for cosmic rays research as well. Just out of curiosity.

Gareth, Chester, England

I feel like we are in the days of Galileo and the Church of humanity is in session. Don't tell them that they might be wrong and the Earth may be round. They might just have to put you to death.

It is a shame that more governments and politicians are not forcing more of these questions to be answered. Most are only interested in short term personal politics.

Pool into the facts that we are over due or in the process or a pole change and the earths own magnetic fields. Which is the single most protective field from the sun and its effects. We humans are in for a ride.

The single thing that concerns me the most is how us humans like to jump from one big quick fix to the next. Historically we end up with things that we only later find out cause worse problems. We do like trauma and drama though. It seems that is the great engine that keeps us going.

Kurt H., East Quogue, NY

It is inconceivable to me that life on earth has no (or little) influence on climate. It is a well known fact that the composition of our atmosphere was created by life. Plankton and plants generate oxygen which makes one fifth of our atmosphere. We have now crreated engines more powerful than men to spill into the atomsphere tons of a different gas. It is inconceivable to me that it has no or little effect.

benzi, Wyckoff, USA

Apparently all the planets in our system are warming up?

How did the SUV's do this?

It is great this article still gets attention!

An encore perhaps?

Wes Parsons, Winnipeg, Canada

Sadly, the whole environmentalist movement is going to get hurt pretty bad for "pushing" this lie for so long. Should have just admitted we were wrong right away.

I'm an enviromentalist. I believed in antropogenic global warming for a long time. But, once I fully researched both sides of the argument, I was ready to puke.

Cheated for so many years.

So much money and effort wasted on a useless cause.

Its a pitty. We probably could have made a real impact had we worked on important issues, instead of using all those resources on a lie.

The longer we push this global warming lie, the worse the consequences for the green movement will be.

Who is going to believe us after this??????

Mike, Calgary,

Certainly there is Global Warming! Do humans contribute to the rise of CO2 in the atmosphere? You betcha. Are we solely to blame for it? No. But we definitely must see that we are contributors, not solely of CO2 emissions, but of a plethora of environmental contaminants. The right-wing agenda of driving big rigs, laying waste to all of nature and using everything for a buck, is alive and well. These people want us to forget that we have work to do. They want to shirk all responsibility solely because we are not the only reason for the troubles ailing our planet. Like Ian Morill here wrote, we need to address a myriad of different environmental issues; and get VERY serious about them all!
The right-wingers are dead wrong about the issue, it can't be ignored.
The left-wingers are dead wrong about the issue, correcting only human CO2 emissions is not the final answer.
We need to address forest depletion, freshwater depletion, animal extinction and the like.

Hanson, halifax,

The biggest blunder is that the Green lobby and the media have allowed us to be painted into a corner on Environmental issues.Are we really so one dimensional that we can only focus on one issue at a time.I remember when all the talk was of Acid Rain then it was the Rainforests and then the Ozone Layer.Now it's Global Warming/Climate Change caused by CO2.Firstly CO2 isn't the only Greenhouse gas, there's Methane and Nitrous Oxide, do we really want to be pumping that into our atmosphere.Secondly it's not just about Global Warming.There's dying coral reefs,soil erosion, deforestation,collapsing fish stocks, river pollution,over population, Global Dimming, mass species extinction, biodiversity, drug resistant disease, increased mental health problems/stress, increased violent crime. All these things and more are definately man made .They are all Environmental issues that urgently need addressing.Meaning we need to drastically change our lifestyles.Lets not get bogged down with CO2.

Ian Morill, Huddersfield, England

The level of ignorance here is astonishing. A tiny fraction of you have any scientific background, or have done any real researchc. Instead you choose to believe what you want to be the case. You ignore the finding of te UN's Intergovernmental Panel on Climate change, which unlike most of the climate change deniers has no vested interest in the results of their work. Why would anyone want to invent a theory that would lead us to sacrifice many of the luxuries we have come to enjoy?

We are not 100% sure climate change is manmade. But cutting emissions to combat it is, at least, an eminently sensible insurance policy to take out on the advice of the most respected scientists in the field. We are fabulously wealthy - it makes sense to invest a small amount of this wealth in averting a potentially catastrophic future which will cause enormous suffering to all humanity.

Alex, Oxford,

Personally, I would be much happier if global warming was entirely due to man-made CO2, as it would be within our control and we could do something about it. I find the idea that the 2,000,000,000,000,000,000,000,000,000 tonne exploding thermonuclear fusion ball that we orbit around may be getting hotter a little alarming. (Hell, if I was neurotic, I would worry about it!)

However, the recent thermal history of the planet does rather suggest that things do get uncomfortably hotter and uncomfortably colder all by themselves with uncomfortable frequency, so there's probably a bit of both going on right now. Still, at least it's getting warmer on this run and not colder...

Larry Kirk, Perth, Australia

Science has and will always be about falsities rather than proofs. We can only come to specific theory once all other possibililities have been exhuasted, and even then, as history as shown repeatedly, this thoery is not fact and must be subject to change, both in the literature and our minds.
I find it both appalling and arrogant that a large number of climate scientists claim #1. That they KNOW man-made GHG's are causing climate change and #2. That they can predict what that will result in 10,20,50 years in the future. Both are fundamentally scientific blunders.
We can't even accurately predict the weather 2 weeks from now. It is obvious that multiple factors contribute to climate. I predict Time will dispell ALL climate change models cased on a single y axis variable as we come to understand the true complexity of the situation.
"Belief in one false priciple is the beginning of all un-wisdom"

D.Darryl Hudson, Guelph, Canada

I will bin the suv , I will recycle loo roll , i will not drink more than 14 units a week but please i need my 2 weeks sunny holiday,

liz, coldtown, colder ireland

I was a sort of 'default believer' in the manmade climate change theory until I saw this article and the TV programme. So, being a scientist, I did some net based research, rather than listening to politicians and half baked journalism. Turns out that there are numerous websites that go into a lot of detail about the few large remaining uncertainties in the models and theories. The good ones are quite technical, but fairly straightforward to understand if you have a background in science, mathematics and predictive modelling. Try it for yourselves, you may be enlightened.

I wont say what my conclusions were, but on the balance of probabilities, and based what I know about greed and human nature, I certainly won't be buying a house on the coast any time soon.

Doug Hunt, Leatherhead,

My understanding is that the burning of fossil fuels constitutes only 5% of the total CO2 emitted into the atmosphere each year, with 37% coming from humans and animals breathing out!

So what odds will anyone give me that in 50 years time when we've been driven halfway back to the stone age, the lunatics running the asylum say to us 'sorry - we now understand that it's the fact you exist at all that is the cause of the problem, so we're going to put the names of every person on earth in a hat, hold a lottery, and unfortunately 40% of you are going to have to hold your breath - forever'

Every single person needs to understand that this is more likely than them conceding they are wrong on the CO2 issue because their stance is not based on rationality. Environmentalism is just the latest way of convincing you to give up the power over your own life that is rightly yours and giving that power to politicians.

Perry Offer, London, London

From this alternative research, it is pretty obvious from the close correlation and time lag between global warming and the following CO2 increase, that it is not CO2 causing global warming but the converse. Also the tiny percentage of CO2 directly attributable to human activities is so small as to be insignificant. So now with this 'new' evidence, why are politicians still saying we must cut emissions? The latest Tory idea of taxing air travel is crazy and completely out of sync with these findings.
It would be refreshing to see the Blair government actually fund more research into these alternative and seemingly more convincing hypotheses.

Robert P Beales, Worcester, UK

CO2 makes up less than 1% of the atmosphere, and is a vital constituent of photosynthesis, upon which all life depends. It seems to me rather unlikely that either halving or doubling this very low level can be the cause of the current global warming.
Big, well funded science has its corporate views, just as does industry or politics,and they are equally likely to be just as silly.
Big Bang cosmology is another example of this sort,but nevertheless is believed by a majority of intelligent practitioners to be a good approximation of reality.
The red faces of the future may not be due to excessive sun worship.

Peter Willey, Chepstow, U.K.

Anyone with a brain knows that is used to get really cold in winter. Before that it didn't get so cold, now it dids't get so cold again. You would call that weather fluctuations, or perhaps temperture differences.
Just because so many tons of smoke goes into the atmosfere doesn't mean to say that it has never been that way before.
Just like those fumes do, and always have done for millions of years, lets see some of those lofty head come back down to earth, where they belong.

Leslie Martin, Dorset, U.K.

After doing a bit of digging I find that the Hadley Centre which has been responsible for most of the research linking CO2 emissions with global warming used by the IPCC was indeed set up by Mrs Thatcher in support of a long running campaign of her own, at a time when she had been cutting budgets in all other fields. I had believed the greenhouse effect was real. Perhaps it is, but all I can say now is that what we have been told about it is the product of a political spin machine masquerading as science.

Charles Francis, Cambridge, UK

Whether global warming is manmade or not, the undisputed fact is we are using a finite source fuel which will not exist for future generations unless we take the right actions now.

Stephen Page, Nottingham, UK

after watching c 4 docu last night i believe that its all a big con ,just to fuel a multi million £ industry and give the so called politicians something to spend tax payers money on.Also to stiffle growth in Africa. God help us if Gorden Brown gets to be P M he will take back into the dark ages...

rob, cardiff, uk

I greatly appreciate the inciteful views of Mr. Calder (and friends) and his willingness to work not for money, not for fame, but for pure science. I suspect that he has brought his views to the public at great personal and professional expense. We should not be so quick to dismiss anyone's views and the data that their research generates. Instead, the information should always be adapted into our current thinking and be used to guide us towards a future of greater understanding, rather than a future of intolerance and blissful closed-mindedness. I don't know if I agree with Mr. Calder's views at this time, but I am CERTAIN that I do not blindly disagree. I simply do not have enough information from the little bit of internet gossip to form a full opinion in the matter. However, I greatly respect the man and his team of fellow scientists for their hard work and efforts in this important endeavor. Thank you.

Harro Penk, Poughkeepsie, USA/NY

I worked in the oil industry for 20 years as a "Chief Engineer on supply vessels" and watched as millions of "btu" were burnt off from from oil platforms. Why can't these assets be used to fuel the homes in Africa that are starving for fuel to cook on and such. I worked offshore in most of the countries on the West African coast from the Ivory Coast to Namibia.They all complain off lack of fuel when they have all the fuel they need to cook etc off of there own coasts. It is only their own governments that are robbing them of the assets they have as it seems they don't bother to implement these schemes.
If their own governments were not so interested in their own profits and cared about their own peoples needs then things would be a lot better.

Brian M Cooper, Sheernes, Kent

I can't believe how gullible the general public is regarding information given by Governments, and the supporting evidence given by scientists with Government grants. regarding the case of global warming.
The real reason for this propaganda of man made Co2 emmissions being responsible for global warming is political and economic power. Africa for instance has an abundance of fossil fuels, coal, oil, gas, but are being prevented from using them and are being encouraged to use solar power instead.
It's ironic that one of the poorest nations should be asked to use the most expensive form of energy, so why doesn't the West use this? The western politicians fear a shift in power from developing countries so they make up propaganda such as this global warming and weapons of mass destruction and oh yes we should be very afraid of this man that lives in a cave that terrorises the world.
Ask yourself this question, when was the last time any government informed you of anything beneficial.

John Rimmer, Oxford, England

Caleb and Michael of Australia, it's all very well being sceptical of experienced scientists from many different fields of climatology, but as Caleb points out climate change is a reality, if we accept the scientists advice then at least we stand a chance of survival; ignore them as you imply without providing an alternative course holds no hope for the future.
You in Australia should be more aware of the effects of drought than us Europeans.

Frank, Barnsley , S Yorks

I'm getting used to this, biased scientists telling us what they want us to hear when they really have very little evidence to study.
This one is not as ridiculous as the one about billions of years and evolution creating somehow the world as we know it.

The fact is that we are not critical enough. We don't test stuff but simply believe what we are told.

Caleb, Geelong, Australia

Time and again people confuse climate change (which is not disputed) with 'man made' climate change (which is uncertain).

Michael, Sydney, Australia

It's very interesting that most people seem to lean heavily toward one side or the other in the climate change argument instead of recognizing that for millions of years there have been periods of extreme heating and cooling that is still going on which caused oceans to rise to much higher levels than where they are now and conversely covered a large portion of the earth with ice. Obviously these eras of fluctuating temperature were not caused by man and had to have some other source such as long solar variations or cosmic ray bombardment. On the other hand, we are brutally polluting our earth with chemicals, heavy metals, radioactivity, coal burning, etc., etc. and just, generally, with the overpopulation of man at the expense of everything else. It seems from the many studies done on green house gases, the tremendous growth in the concentration of certain ones is contributing to the heating of the earth that was already going on. As some other people have said, it really is in the best interest of everyone and everything to clean up our act, especially if we hope to have a future on this planet.

Jane Flatt, Salem, Oregon

How do you explain the smog blankets, yes the climate is very complex but the temurature has rised quite a bit in the last 50 years, and what is new , fossil fuel technologyls, and it is starting to catch up to us. Climate change is completly caused by man, theres to much evidence to prove it wrong.

olivia, missisauga,

To Nigel,

You say sea-levels have increased in the Southern Ocean because Antarctica is melting. Well, only one small part of Antarctica is melting, the rest is getting colder, as the article points out, and the amount of overall ice in Antarctica is also increasing.

gabe, minneapolis,

Jim Lloyd said
"To all the doubters. Imagine if the security services announce that they have carried out extensive surveillance by thousands of their operatives and are 90% sure that extremists intend to cause an explosion in your town on Saturday, so for everyones safety please stay away. All rational people will be sensible enough to heed this advice"

Actually, closer analogy is some group of scientists saying that they have studied brain chemistry of extremists and from this brain study, they are 90% sure that these extremists will cause an explosion in your town on saturday.
Basically, these scientists are predicting the future with only small, partial understanding of all factors involved in the climate system. That is the key word, "system". Not one factor determines the outcome, in this case being the temperature of the world. There are counter-balancing factors involved that is not fully understood.

Ben, Austin,

To Jim Lloyd of Liverpool,

I have never read a more stupid analogy. If you really think that man can control the world`s climate, then you are living in cloud cuckoo land. Since the UK produces just 0.08% of total CO2 emissions (only 4% is manmade and the UK produces just 2% of that), then cutting all of that would not make a ha`porth of difference. The climate is the most complex, non-linear, chaotic system known to man. By definition, it cannot be predicted. Don`t try to stifle proper scientific analysis and debate on this most complex of subjects. We should encourage investment in the development of new fuels and sensible forms of power generation to assuage our thirst for energy. Just don`t expect or force us to waste money on useless projects like wind power, a most inefficient and intermittent form of supply. Solar energy is pretty useless at night as well!

Meanwhile, we must accept that climate is always changing naturally and adapt accordingly.

Rowland Pantling, Colchester, Essex

Nigel,
Everyone knows that sea-ice has increased in the Southern Ocean because of the melting of Antarctica. And talking of new scientific theories, 90% of the world seems to think that the earth is round. I feel very privileged being in the other 10%, getting ready to storm through with a new idea.

Nick, Narromine , Australia

To all the doubters. Imagine if the security services announce that they have carried out extensive surveillance by thousands of their operatives and are 90% sure that extremists intend to cause an explosion in your town on Saturday, so for everyones safety please stay away. All rational people will be sensible enough to heed this advice, but there will be deniers who think they know better and accuse the security people of acting out of political malice or scare mongering in order to ceate work for themselves.
The damage from climate change will be unimaginally greater than anything terrorists can do, but it can be kept within bounds if we all take a few simple cautionary measures.

Jim Lloyd, Liverpool,

Paul -

"We people" may or may not be mad, but the proposed "solutions" to anthropogenic global warming are certainly madness. The harnessing of commercial sources of energy is one of the primary characteristics of modern society, with resulting improvements in health and living conditions pushing life spans to nearly double those of the pre-industrial world. The idea that we can use renewal sources of energy to replace oil, coal, and nuclear power is absurd.

Also, I would suggest if the major problem facing mankind is that of global warming, then to embark on a series of efforts known in advance to be futile while damaging society's ability to respond to future challenges is absurd. The reality is that the issue of anthropogenic global warming has nothing to do with science and everything to do with socialist political agendas. Karl Marx would be proud!

Jim, Lexington, USA

I don't understand what all the arguing is about! Who cares what the actual cause of global warming really is? The important thing is that we humans get to work on cleaning up our environmental pollution which will benefit us all! If people believing humans caused the greenhouse gas problem gets us all to work on cleaning the environment, isn't that all that matters?

Bonita Poulin, Quadeville, Ontario

...if people assumed that science was devoid of politics before, this debate on global warming will shake that belief. If one understands that the causes of global warming can never be truly known, and that they will always be open to debate, then who is right or wrong ceases to matter in this case. Given this, the decisions that goverments make about global warming can only be based on the fact that if we do nothing and global warming scientists are right then we would all look a bit stupid when we are up to our knees in Thames water. While we may sacrifice some aspects of our lifestyles and modern living to try and avoid this scenario, the chances are, if global warming theories do turn out to be wrong, the result will still be good; we will all live in a better, more sustainable and less polluted world and where people are less selfish and the scientists more politically aware - which can only be a good thing.

Dr Glenn Smith, London, England

Why should we pay attention to Nigel Calder, a journalist? Why should we pay attention to the comments here by those who present a single "problem" for AGW and imagine that it is a refutation? The level of discussion here is astonishing. Far better to go to www.realclimate.com where you will find real scientists discussing these and other issues at a level far above the grade school level of Calder's article. Elitest? You betcha. Science is elitist. Those who are better at describing nature are the winners.

Ironically, Calder enlists the example of Galileo, who saw the truth about the structure of the solar system at a time when there were objections far more serious than any raised against AGW. He saw clearly where the preponderance of evidence lay. Those who imagined that the lack of observed parallax was a problem would have to wait 200 years to come around. We are in the same position now: Calder is like the Church authorities. Except that we cannot afford to wait.

LA Coleman, Little Rock, Arkansas/USA

I think everyone is in agreement that climate change is happening now. The only point of contention is what action to take. Either sit back and do absolutely nothing and wait for the wheat producing regions to turn into dust bowls or take the advice of the majority of independent climate scientists and cut back on fossil burning fuels.
Option one will suit the defeatists whereas option two at least gives humanity some hope.

Bil Linford, Cambridge,

If you believe man is causing global warming, you will believe anything; if you believe man can stop global warming, you will believe anything; if you believe the world is running out of resources, you will believe anything; if you believe the .28% man contributes to greenhouse gases outweighs the 99.72% that is contributed by natural causes, you will believe anything.

And since you will believe anything, the best solution is to ask Santa Claus to fix global warming this Christmas. That's a much better solution than ruining the global economy over what is nothing more than a fabrication of Al Gore's imagination.

Kevin, Kinston, NC USA

Well it seems if we read the comments that the people who favour climate change will not be willing to let go very easily their intellectual dictatorship...
What a bunch of great scientists they make if they cannot even consider another theory without insulting people!

Thierry, Los Angeles, USA

Why are some people so hostile to any comment that may threaten their view of global warming? I think people should live a greener lifestyle anyway, as we cannot go on consuming resources the way we are, but don't attack others for their views, there is a right to free speech after all.

amanda, manchester, england

you people are mad ...

we have devastated ecological systems world wide that sustain life on earth

the sad thing is people actually believe that there is scientific controversy on the reality of anthropogenic warming !!

Paul, Kyogle, Australia

The comments provided here are, in most cases, as informative as the article. Thanks to all contributors providing verifiable corroraboration for the substance of the article. It gives credibility to the thesis --- something that Al Gore's speech fails to do for his thesis. Al Gore recently came to our city to speak about global warming. I have no political party allegiance. I wanted to hear his proof for the causative link between observed changes to the environment and man-made green house gases. I was so disappointed to hear MOSTLY a politician on a soap box. I left with one certainty, -- if the future of the world is dependent on a career politician convincing the rest of us of his version of "scientific certainties", we are all doomed.

MK Denton, Meridian, Idaho

To David Bright. To use the wording "Cuckoo Science" regarding a theory contradicting your one, suggest to me that somebody can not use real scientific arguments. I have put quite a lot of effort to find viable scientific theories on how the increase of the percentage of CO2 in air of some 0,01 % may result in a increase of several degrees. What I have found are statistical relations based on a selective set of data and measurement period plus a vast number of more or less wild ideas on dynamic effect.

So David Bright or somebody else. GIve me some links to real scientific proofs for the theory that mankind is the main cause of the current climate change.

Sven Hanssen, Stockholm , Sweden

It is a sad reflection on some members of the present 'scientific' community involved in research into the causes of climate change that they need to threaten the funding and the academic advancement of scientists prepared to publish evidence which is contrary to the politically acceptable belief that greenhouse gases are the main cause of the 20th century warm period. There is sufficient concrete evidence from historical, geomorphological, marine , biological and atmospheric physics sources to show that climate change cannot simply result from greenhouse gases. To deny such factual evidence an equal place in the debate on climate change, to marginalise it, or ignore it, only serves to discredit the present pronouncements of the 'alarmist' green lobby. The selective dismissal of data, which may not allow the attainment of preconceived conclusions, is not an option if truth and accuracy are to be the most important outcomes from the use of mathematical models and computer simulations.

Robert Forrest, Mauchline, Scotland

There are more indications that global warming is not mainly to blame on human activity. Examination of annual rings of very old trees has shown that the earth was a lot warmer around 1200 than it is now. Also the eruption/explosion of the Krakatoa in 1883 has influenced weather and temperatures on a global scale far into the 20th century. These are only two indications that I know of.
It seems that the protagonists of the global warming theory only want to hear the things that suit them. An inconvenient truth perhaps?

Gerda van den Berg, Voorschoten, The Netherlands

"No God is greater than truth"

Joshua Walker, Hope, R.I., U.S.

Seems to me that there are plenty enough reasons to live a "greener" lifestyle whether or not mankind is responsible for climate change.

mike orman, penzance, UK

I look forward to reading "The Chilling Stars"--powerful and arresting information for anyone who farms in northern latitudes.

The idea that man's activity is bound to plunge the planet into a crises of Biblical proportions--warming, cooling, or oozing--amounts to ideological preaching about man's alleged moral "depravity". Green "scientists" don't much care about facts and evidence; what do care about fervently is grasping political power to impose their goals on everyone else. That's why they screach about "consensus".

The notion that man's production of C02 could somehow overwhelm the titanic forces of astronomy and climate has always seemed preposterous. Anthropological C02 comprises roughly 5% of atmospheric C02, which in turn makes up roughly 2% of total greenhouse gases that absorb heat radiated off the earth toward the heavens. Water vapor or cloud cover comprises about 98% of total greenhouse atmospheric gases! A 1% increase in cloudiness offsets a doubling of man's C02!

Mark A Humphrey, Great Falls, USA/Montana

Actually, I've never heard Al Gore claim to invent the Internet. He claimed to have coined the term "information superhighway". He was referring to his early recognition that the Internet would become a form of vital economic infrastructure, similar to our interstate highways, and perhaps deserved further public support of the kind that created it in the first place. I know this to be true because I actually read an article he wrote on this topic, long before the Internet's promise was widely recognized. In other words, he was ahead of the curve. While the media does inappropriately hype recent events that consistent with the climate change hypothesis, I consider Nigel Calder's extrapolation from a few contrary observations to be a clear example of the very "bad science" he decries. He concludes that global warming "makes no sense" because of regional cooling in Antartica? I'm all for testing scientific orthodoxy, but that is patently absurd at best, and irresponsible at worst.

Martin, Seattle, Washington

Why do we put so much into what Al Gore says? Didn't he claim to have invented the internet a few short years ago? Just putting that out there for people to chew on...

Katie, Cincinnati, United States

You couldn't be more right!

In Winnipeg Canada I saw on the net that the world just experienced it's warmest ever year, while on the same day we heard in the local media, something that was more than obvious, Winnipeg is having it's coldest winter in 10 years!

Not to mention summers have been cooler here for the last 20 years in decline from a record year of heat in 1980!

Wes Parsons, winnipeg, canada mb

No evidence that mankind is not the primary reason for long-term warming that might be occurring? Unfortunately, this site limits comments to a 1,000 characters. So how to use those 1,000 characters? Best to just say there are MANY excellent Web sites filled with facts confirming mankind flatters itself by proclaiming it has the ability to make such massive changes even if everyone wanted to do so. Ecology "Mankind is Evil" Web sites are almost always carefully edited facts but mostly emotional rhetoric. Government funding of studies are available only to those who agree to predetermined findings. Anyone employed in the sciences signs their career death warrant if they put their name on anything that isn't in lock step with, say, Al Gore's "factual" movie. I'm amazed so many are brave enough to "come out of the closet" and write and speak the complete facts and data of GW. They must feel like those in the Middle Ages who were executed for declaring the earth is round.

Gary Yantis, Shawnee, Kansas

I have already sent one comment on this article. Why is it not included in your list?? Did my own castigation of the Times for uncritically publishing such material hit a nerve??
I again suggest that the Times Science Editor looks at the link from www.realclimate.org to a highly critical analysis of Svensmark's gross over-estimate of the potential climatic effects of cosmic rays. This analysis mentions original work on this very subject by John Tyndall in 1859, which strangely also resulted in what we would now describe as 'spin' in the London press on similar lines.
The scientists who manage the RealClimate website refer to this kind of stuff as 'Cuckoo Science'. The Sunday Times was ill-advised to foist such material on gullible readers. Perhaps they accepted Calder as an authority - however, the strident tone of his article suggests he is more a journalist than a scientist.

David Bright, Maidenhead, UK

I'm a bit behind on the news. What happened to the scientists who were warning us about Global Cooling in 1972 and even tried to get the members of the United Nations to join together in a multi-billion (trillion?) dollar program to coat the poles with black soot to increase earth's temperature? They sure had my attention and they had all the "facts" down pat. If it hadn't been for the Vietnam War and the first Gas Crisis, they'd have caught on. But there were too many other sexier things to protest and march against. Global Cooling was boooring. Facts like Mars warming faster than the earth don't get mentioned. That the temperature of the sun varies as does the axis rotation of the earth and both track with earth's temperature! Global Cooling is already being explained away as really Global Warming in disguise. It's the fault of man no matter what to the religion of ecology. It is a religion just like communism was a religion. Mindless emotion always wins.

Gary Yantis, Shawnee, KS

Why is the ice melting more in the north than the south? Probably because most of Antarctica is ice on land, not on the ocean. Where is the proof that rising temperatures cause more CO2? Some data from the past indicates that CO2 lags temperature rises. Why do we mix agendas? Yes, let us control emissions that cause pollutants, but let us not destroy real climate science by continuing to evade natural causes of our recent global warming. Humans are always trying to make themselves more important than Nature.

fred cuhl, Pasadena, USA

Most people on this site dismissing the fact that global warming is real do not bring up any scientific evidence. Yes, I know, millions of dollars are spent to promote and expand the current theroy of global warming. This is because a lot of people in this world, are stubborn, one sided, and corrupt. However there are many people who think global warming is fake and they will search day and night to find one person with some evidence supporting their opinion. So lets forget about politics. Industry, cars etc create CO2 emmisions. When CO2 increases, so does the temperature, and when the temperature increases, bad things like rising sea levels, melting polar ice caps and droughts happen. Im not some eco-radical "destory the modern world to save the earth" person, but I do believe that polutants were creating are harming the earth and will soon be deadly. We can help prevent this. Why is ice in the north melting more than in the south? Maybe because most industry is north of the equator.

Justin, Bedminster, NJ

It's pretty obvious to me that the IPCC Feb 2007 report is a lot of hot air, fueled by the billions of dollars of research funds that go to the scientists and activist groups behind the report writers.
The arrogance of saying man is causing climate change is only exceeded by the stupidity of saying we can - and must - do something to stop it. This whole hoax just goes to show how money makes the world go around..

max anacker, maienfeld, switzerland

The author of this piece is ignoring some important points.
Global warming does not just affect air temperatures but also ocean temperatures which have a huge influence on climate and weather patterns and this is why there is more and more flooding in some areas, drought in others and global weather patterns are changing - like those unexpected frosts. This is also the reason why migratory birds are showing up earlier and later because they rely on weather patterns for their cues and since the weather patterns are changing they too have had to change their behaviour.
Scientists have been studying ice core samples for decades, dating back 600 thousand years, measuring gas levels and calculating temperatures at the time the ice was formed, and yet any of the warming and ice age periods during this time do not even compare with the data collected from samples of ice formed in the last 100 years. The premise in this article just does not stand up when all of the facts are mentioned.

Sarah, wa, aus

How about the much less geo-centric notion that we (humans) neither cause nor can change everything things as large as Global Climate Change. More important is the cyclical nature of these changes and how misinformed the politico's have made the masses. The fact is that there are things on the planet that can't be controlled, intentionally misleading the people about the nature of the planet is a crime. Man becomes lulled into a false sense of empowerment, deciding against the taking of individual steps to prepare for whatever drastic changes may be coming. Global warming as a science is a sham.

Jay, Honolulu, HI

Changes in solar output are taken into account by climate models, as J. Patrick mentioned above. The author of the article mentions the Little Ice Age and Medieval Warm Period, but doesn't mention that the current temperature departures are well outside the natural range seen in those periods.

Climate models (which also take solar variation into account) can reconstruct past climate quite accurately, up until the 20th century, when suddenly the climate models don't reproduce the observed warming trend. Add increased greenhouse gases into the same climate models and they suddenly accurately reconstruct the warming for the 20th century.

Bryan, Amsterdam,

There is an experiment i have heard about, if the CO2 rises in the atmosphere, the trees should grow bigger (immediately) because it is easier for them to absorb the co2. I had also heard that trees beside a forest just burnt will grow faster. if you doubt lets see if we can rule it out with this experiment, do something like this:

set up a glass house outside put some sprout seeds in stockings with sand/soil inside on the floor (with some irrigation). then buy CO2 gas bottles and fill the house with water, then put the co2 into the building, the pressure forcing the water out so you have 100% co2.
and set up another glass house with normal air. with the same arrangement inside (perhaps give them a dip identical to the other arrangement too!).
so the plants will be receiving identical light (through glass) at identical times.

Charlie, Mackay, Australia

It seems either solution require a 'leap of faith', however the point is if the earth is warming up (may be good or bad) what are you going to do about it? Finger pointing doesn't get the job done. We have proven in the past that everytime man tries to resolve or fix a thing of nature we end up screwing it up. Let's study this problem until we can come up with solution that is better then just 'very likely' to succeed.

Rich Nocis, Solvang, CA

I applaude the above post, for setting things straight. While, yes I am glad whenever I see someone challenging the popular theory instead of silently goign along with it, I am equally glad to see someone reminding us of just why popular theories are popular in the first place: because they tend to be right.

Hunter Shea, Green Bay,

Global warming has become a highly charged, emoti