Posted on 02/02/2007 2:51:54 PM PST by SirLinksalot
Comment: 'Harder than ever for cynics to dismiss global warming'
Mark Henderson, Science Editor of The Times
The IPCC's 'uncharacteristically robust' conclusion means the debate on climate change is over
Like all groups that decide policy by committee, the Intergovernmental Panel on Climate Change (IPCC) is naturally prone to conservatism.
Every line in its Summary for Policymakers is fiercely contested, and must be approved by a consensus of more than 300 expert scientists before it is included in the final document.
The panel’s uncharacteristically robust conclusion that global warming is "very likely" the result of human activity is therefore cause indeed to declare the debate over, as David Miliband, the Environment Secretary, has done this morning.
Much of the report’s significance lies in the way its language has become more confident since the IPCC’s last effort. Where the 2001 document found "new and stronger" evidence that most warming is human-induced, the new one declares there is more than a 90 per cent chance that this is so.
A graph, published on page 16, makes this particularly plain. A series of long bars show how gases produced by humans have contributed to rising temperatures, above a stubby one detailing the influence of the Sun — the favoured alternative of the greenhouse deniers.
Even sceptics have stopped claiming that global warming is not happening. It will now be harder than ever for them to argue that temperatures might be going up, but that we are not responsible.
The 90-per cent confidence level might leave some room for uncertainty, but, as the Met Office has pointed out, every business makes decisions based on probabilities that are far lower.
There are other important new conclusions, too. The panel now thinks that temperatures are in line to rise even more steeply than it did six years ago: the likely increase by 2100 is up from 3C to 4C, and the maximum is up from 5.8C to 6.4C.
Another significant figure is the probable increase given a doubling of pre-industrial carbon dioxide levels to 550 parts per million — a figure that the government thinks could be politically achievable.
Even that target will lead to likely temperature changes of between 2C and 4.5C, with a best estimate of 3C. Without drastic action to curb emissions, the world is clearly going to get a lot warmer.
It is also interesting that the IPCC has assessed it as "likely" — a better than 66 per cent chance — that global warming is increasing the intensity of hurricanes and other tropical storms. Previous reports have steered clear of this issue, but a wealth of evidence published in the past three years has now shown that hurricanes are almost certainly getting stronger, if not more frequent
OK Folks, let's deal with THE SCIENCE, not the politics.
1) Is it an established scientific fact that we have Global Warming today ?
2) Is It an established scientific fact that Man Made Emissions Play A Significant Role in Global Warming ?
Anytime someone announces that a debate on a controversial topic is over, I tend to believe that the source is lying.
I don't think I am the only one.
Why is global warming a bad thing?
Dinosaur SUV's were to blame for that last several periods of global warming... (/sarc)
The climate is changing. Just like it has for the last few billion years. Our .2% contribution to it isn't going to melt so much as a single ice cube in my scotch.
I would think that you would only have to point out that tempertures are also warming on Mars to refute that notion.
1) The earth has been warming for around 12,000 years on a relatively smooth scale.
2) Man has had nothing at all to do with it.
2. No. 186 billion tons of CO2 were produced globally last year. Only 6 billon tons of it came from man made sources including the estimated amount from us breathing. Considering CO2 only accounts for 2.3% of the total "greenhouse effect", the human contribution is well within the error of margin for most observations.
Like the TAR, which allowed a prominent Mann to insert unchecked work all over the document, to generally run amok, and which instead of explaining why previous counterevidence no longer applied simply dropped references to it? Yeah, right.
Increases in CO2 lag increases in temperature and a close look reveals time periods where increasing CO2 levels lead decreases in temperature . Why?
Really. What if Global Warming brought monsoons back to Saharan Africa? Lengthened our growing seasons?
"A graph, published on page 16, makes this particularly plain."
This I gotta see. If it's so obvious from one graph, then it seems strange that none of the recent news releases have been able to explain in simple terms how the evidence supports the "man-made" hypothesis.
Oh well. It was a good debate while it lasted. Time to go nuclear!
2) Is It an established scientific fact that Man Made Emissions Play A Significant Role in Global Warming ?
1. There is data to suggest there may be climate change. There is also a great deal of uncertainty as to how much things are warming. Some areas are in fact cooling.
2. The jury is out on if manmade contributions to greenhouse gases are in fact signifigant.
Bump for later reading. I have no idea how to resolve question #1, so it should be interesting.
When they can predict the weather more than three days out - or even when their models fed old data can correctly "predict" known weather results - they can have a shred of credibility.
What is the source of this chart ?
When this argument began, temperatures were not distinctly rising, and were in fact, mildly dropping in the face of a rapid increase of GHGs after having risen much more dramatically under lower GHG levels. It is only now that we've mostly surpassed the 1930s temperatures, where temperature increase, even retroactively is only evident beginning in 1995.
One of the qualms is that the increase in the average temperature is contained to a surprisingly large measure within individual years...1998 and 2003 were more than a 20 century's worth of increase higher than the years before and after. Obviously this wasn't driven by GHGs (since they didn't go up 2000ppm in one year, and then down by a like amount, the next), but what it was driven by is only touched on.
"Why is global warming a bad thing?"
I don't know, but if this global warming continues I'm going to freakin freeze to death!
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