New paper should end the global warming debate

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In a major, refereed journal:

http://tinyurl.com/2f9fyv

Friends who follow the global warming debate feel this one will end the debate. The predictions which generate hysteria are all based on models and not real data, and this one indicates that the models are not capable of getting better than bad.

Quote:

Climate is too complex for accurate predictions

* 19:00 25 October 2007
* NewScientist.com news service
* Jim Giles

Climate change models, no matter how powerful, can never give a precise prediction of how greenhouse gases will warm the Earth, according to a new study.

The result will provide ammunition to those who argue not enough is known about global warming to warrant taking action.

The analysis focuses on the temperature increase that would occur if levels of carbon dioxide in the atmosphere doubled from pre-Industrial Revolution levels. The current best guess for this number - which is a useful way to gauge how sensitive the climate is to rising carbon levels - is that it lies between 2.0 C and 4.5 C. And there is a small chance that the temperature rise could be up to 8C or higher.

To the frustration of policy makers, it is an estimate that has not become much more precise over the last 20 years. During that period, scientists have established that the world is warming and human activity is very likely to blame, but are no closer to putting a figure on exactly much temperatures are likely to rise.
Positive feedback

It now appears that the estimates will never get much better. The reason lies with feedbacks in the climate system. For example, as the temperature increases, less snow will be present at the poles. Less snow means less sunlight reflected back into space, which means more warming.

These positive feedbacks accelerate global warming and also introduce uncertainty into estimates of climate sensitivity, say Gerard Roe and Marcia Baker of the University of Washington in Seattle.

What is more, they found that better computer models or observational data will not do much to reduce that uncertainty. A better estimate of sensitivity is the holy grail of climate research, but it is time to "call off the quest", according to a commentary published alongside the paper.
Deep uncertainties

That is likely to fuel attacks by critics in the oil industry and elsewhere who argue against investing in measures like clean energy until more is known about climate change. Others say that we need to act even if climate sensitivity lies at the low end of the scale, since coastal areas would still be threatened by rising seas, for example.

Ultimately, the papers also illustrate the limits to which models, even those produced by powerful supercomputers, can help politicians make decisions.

"This finding reinforces not only that climate policies will necessarily be made in the face of deep, irreducible uncertainties," says Roger Pielke, a climate policy expert at the University of Colorado at Boulder, US. "But also the uncomfortable reality - for climate modellers - that finite research dollars invested in ever more sophisticated climate models offer very little marginal benefit to decision makers."

Journal reference: Science (vol 318, p 582)

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And in the very same magazine -Science- published a couple of days earlier ...

Quote:

Planet's CO2 Production Surges
By Phil Berardelli
ScienceNOW Daily News
22 October 2007

An international team of scientists has taken another look at how rapidly Earth's atmosphere is absorbing carbon dioxide (CO2)--the biggest greenhouse gas in terms of volume--and the news is not good: A high-flying world economy is pumping out the gas at an unprecedented rate. Current CO2 production is outstripping the best estimates used by modelers to predict future climate trends.

Oh, and this is the abstract of the above mentioned study

Quote:

Uncertainties in projections of future climate change have not lessened substantially in past decades. Both models and observations yield broad probability distributions for long-term increases in global mean temperature expected from the doubling of atmospheric carbon dioxide, with small but finite probabilities of very large increases. We show that the shape of these probability distributions is an inevitable and general consequence of the nature of the climate system, and we derive a simple analytic form for the shape that fits recent published distributions very well. We show that the breadth of the distribution and, in particular, the probability of large temperature increases are relatively insensitive to decreases in uncertainties associated with the underlying climate processes.

Certainly, gunga, you've read the full report and can quote from where (page, please) you got the idea of your headline here.

Or are you referring to the conclusins here summed up in Nature?

Quote:

They and other climatologists are now calling on policy-makers to make decisive policies on avoiding dangerous climate change, even if we don't have perfect models. This means focusing on keeping the planet's temperature below a certain point (and being willing and able to adjust emissions targets to achieve that), rather than trying to work out far in advance the amount of greenhouse gases in the atmosphere that will produce that level of warming.

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Nobody's going to deliberately and severely hose the entire economies of industrialized nations on the basis of models which are incapable of getting better than bad. It's over.

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So it's your own conclusion based on the deep knowledge of the topic and examination of that study.

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Why on earth would this end the debate?

It is simple fact that CO2 increases temperature. Therefore the more C02 you pump into the air, the hotter the planet gets. There's no argument about that, even in your posted article.

There is also no argument that the earth is warming. That is fact.

The earth goes through periods of warming and cooling.

The current period of warming is believed to be the fastest ever warming.

What is argued about is what percentage of the current warming the CO2 humans have pumped into the air is responsible for.

Consider the known : it is known that CO2 increases temperatures, and it is known that temperature is increasing rapidly (for earth cycles)

Consider the unknown : it is unknown the exact temperature gradient increases CO2 causes, and it is unknown just how hot we will make our planet by pumping out C02

Possible conclusions :
We are destroying ours planet without 'knowing' it (just 'suspecting' it)
If so : we have it within our power to save our planet.

We are knowingly contributing to the warming of our planet...not knowing if our contribution will end up destroying it.

There are no other possible conclusions. We know it causes warming, and we are by pumping more CO2 into the atmosphere, warming the planet. What we don't know is if we will destroy it....but considering the unprecedented speed of the warming...coinciding with the vast amounts of CO2 we are pumping into the air...

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vikorr wrote:

Why on earth would this end the debate?

It is simple fact that CO2 increases temperature. Therefore the more C02 you pump into the air, the hotter the planet gets. There's no argument about that, even in your posted article....

The amount of CO2 and methane humans produce is too miniscule to affect climate. Moreover, Algor and other doom criers have presented their case as if CO2 historically were a CAUSE of rises in global temperature. That is patently false; rises in CO2 levels have always LAGGED rises in temperatures by several centuries, i.e. the temperature increases have always CAUSED the rises in CO2 levels.

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New paper should end the global warming debate

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