The human cause of climate change: Where does the burden of proof lie?

Nov 03, 2011

The debate may largely be drawn along political lines, but the human role in climate change remains one of the most controversial questions in 21st century science. Writing in WIREs Climate Change Dr Kevin Trenberth, from the National Center for Atmospheric Research, argues that the evidence for anthropogenic climate change is now so clear that the burden of proof should lie with research which seeks to disprove the human role.

In response to Trenberth's argument a second review, by Dr Judith Curry, focuses on the concept of a 'null hypothesis' the default position which is taken when research is carried out. Currently the null hypothesis for attribution research is that humans have no influence.

"Humans are changing our climate. There is no doubt whatsoever," said Trenberth. "Questions remain as to the extent of our collective contribution, but it is clear that the effects are not small and have emerged from the noise of natural variability. So why does the science community continue to do attribution studies and assume that humans have no influence as a null hypothesis?"

To show precedent for his position Trenberth cites the 2007 report by the which states that global warming is "unequivocal", and is "very likely" due to human activities.

Trenberth also focused on climate attribution studies which claim the lack of a human component, and suggested that the assumptions distort results in the direction of finding no human influence, resulting in misleading statements about the causes of climate change that can serve to grossly underestimate the role of humans in .

"Scientists must challenge misconceptions in the difference between weather and climate while attribution studies must include a human component," concluded Trenberth. "The question should no longer be is there a human component, but what is it?"

In a second paper Dr Judith Curry, from the Georgia Institute of Technology, questions this position, but argues that the discussion on the null hypothesis serves to highlight fuzziness surrounding the many hypotheses related to dangerous climate change.

"Regarding attribution studies, rather than trying to reject either hypothesis regardless of which is the null, there should be a debate over the significance of anthropogenic warming relative to forced and unforced natural climate variability," said Curry.

Curry also suggested that the desire to reverse the null hypothesis may have the goal of seeking to marginalise the climate sceptic movement, a vocal group who have challenged the scientific orthodoxy on climate change.

"The proponents of reversing the null hypothesis should be careful of what they wish for," concluded Curry. "One consequence may be that the scientific focus, and therefore funding, would also reverse to attempting to disprove dangerous anthropogenic climate change, which has been a position of many sceptics."

"I doubt Trenberth's suggestion will find much support in the scientific community," said Professor Myles Allen from Oxford University, "but Curry's counter proposal to abandon hypothesis tests is worse. We still have plenty of interesting hypotheses to test: did human influence on climate increase the risk of this event at all? Did it increase it by more than a factor of two?"

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More information: DOI: 10.1002/wcc.142

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User comments : 29

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Doug_Huffman
2.3 / 5 (3) Nov 03, 2011
Karl Popper's falsification is a fine razor cutting science from nonsense and solving the problem of induction/demarcation.
Vendicar_Decarian
0.5 / 5 (41) Nov 03, 2011
If you can falsify the observed fact that CO2 absorbs IR, then be my guest.

Post your falsification here.
rwinners
3.7 / 5 (6) Nov 03, 2011
This sounds abstract. Point is, climate is warming and if we can do something to slow that down, I think it would be a good thing.
ryggesogn2
1.7 / 5 (12) Nov 03, 2011
The burden of proof lies with those who want to impose socialism to 'fix' the problem. They must also prove their solution will be effective and there are no other sources of energy that affect climate. Else their 'fix' will trigger an ice age and they will have NO idea why.
ryggesogn2
1.4 / 5 (10) Nov 03, 2011
"Heres what the Club of Rome said on the rear cover of the massive best-seller Limits to Growth in 1972*:

Will this be the world that your grandchildren will thank you for? A world where industrial production has sunk to zero. Where population has suffered a catastrophic decline. Where the air, sea and land are polluted beyond redemption. Where civilization is a distant memory. This is the world that the computer forecasts.

"Science is the belief in the ignorance of the experts", said Richard Feynman."
"So whats the problem? The problem is that you can accept all the basic tenets of greenhouse physics and still conclude that the threat of a dangerously large warming is so improbable as to be negligible, while the threat of real harm from climate-mitigation policies is already so high as to be worrying, that the cure is proving far worse than the disease is ever likely to be. Or as I put it once, we may be putting a tourniquet round our necks to stop a nosebleed."
http://www.bisho
ryggesogn2
2.1 / 5 (11) Nov 03, 2011
"So to say there is a consensus about some global warming is true; to say there is a consensus about dangerous global warming is false."
http://www.bishop...esy.html
astro_optics
3.7 / 5 (3) Nov 04, 2011
Yeap, Guilty before proven innocent!
Vendicar_Decarian
0.7 / 5 (42) Nov 04, 2011
"The burden of proof lies with those who want to impose socialism to 'fix' the problem." - RyggTard

Once again RyggTard shows that he denies the reality of global warming as demonstrated by science in order to preserve his own Libertarian Political Ideology.

Nothing could be more corrupt.

Vendicar_Decarian
0.8 / 5 (43) Nov 04, 2011
"So to say there is a consensus about some global warming is true" - RyggTard

Odd. Last month RyggTard was demanding that there was no consensus.

He will say anything to protect his sick Libertarian/Randite political Ideology.

I have never met a Libertarian/Randite who wasn't a congenital and perpetual liar.
lairdwilcox
1 / 5 (6) Nov 04, 2011
Controversial? But don't all progressives and AGW people know that deniers are just a bunch of fascists and corporate stooges? Thinks are really getting interesting when people begin to concede that AGW claims are "controversial." What we need are some good national debates.
Sigh
4 / 5 (4) Nov 04, 2011
The burden of proof lies with those who want to impose socialism to 'fix' the problem.

That element of theory of science is new to me. Why should burden of proof depend on political persuasion?

They must also prove their solution will be effective

I quite agree. A while ago, I asked you to meet that same standard. You offered only a solution that works for problems localised to areas over which someone could assert property rights. You had no solution for anything that doesn't conveniently stay in one place where it affects only the owner. Does that lack of a solution you find acceptable contribute to your opposition?

and there are no other sources of energy that affect climate. Else their 'fix' will trigger an ice age and they will have NO idea why.

No. It is necessary to know how effective any fix is, not to demonstrate that the thing you change is the ONLY contributor to climate.
dustywells
1 / 5 (2) Nov 04, 2011
It's been decades since I saw a truly blue sky. Assuming that there is an anthropogenic cause, it could easily be the high flying jets that dump water vapor in the high atmosphere where it should not naturally occur. That would be easy to verify by limiting the height of aircraft to below 10,000 feet for a week. Another major change in the environment coinciding with the "CO2 increase" has been the destruction of the Amazon jungle which has previously had a cooling effect. Has anyone proof that these do not cause more warming than CO2?
dutchman
3 / 5 (2) Nov 04, 2011
The most convincing solution to global warming (yes, I said the G-W phrase) that IS happening right now: Population control - universal access to birth control. NOTHING else will be anywhere nearly as effective.

(From a lecture on UC(University of California)TV about a year ago.)
dutchman
3 / 5 (2) Nov 04, 2011
Has anyone proof that these do not cause more warming than CO2?


"...these..." what, forests? In that case, YOU asked the question, YOU go design an experiment. There may be even a Nobel Prize waiting for you.
dustywells
1 / 5 (5) Nov 04, 2011
"...these..." what, forests? In that case, YOU asked the question, YOU go design an experiment. There may be even a Nobel Prize waiting for you.

What? You are so full of the propaganda that you deny that there could be other causes for anthropogenic global warming than CO2. I'm sure that scientists have studied these other causes but they don't fit your concept of science because they don't attack fossil fuel or population size.
kaasinees
1 / 5 (2) Nov 04, 2011
The most convincing solution to global warming (yes, I said the G-W phrase) that IS happening right now: Population control - universal access to birth control. NOTHING else will be anywhere nearly as effective.

(From a lecture on UC(University of California)TV about a year ago.)

I believe the leaders are preparing for another world war.
Doom1974
1 / 5 (1) Nov 04, 2011
"...these..." what, forests? In that case, YOU asked the question, YOU go design an experiment. There may be even a Nobel Prize waiting for you.


What? You are so full of the propaganda that you deny that there could be other causes for anthropogenic global warming than CO2. I'm sure that scientists have studied these other causes but they don't fit your concept of science because they don't attack fossil fuel or population size.

Where are their papers and scientific studies ??? AAAH must be a conspiracy tinfoilman
Voleure
5 / 5 (1) Nov 05, 2011
I lost brain cells reading several of the posts on this thread. Sadly I will never get them back :(

As for the actual topic I cannot see flipping the standard methods will make any difference at this point. The unconvinced will remain so as evidenced by many of the posters here. In fact it will just add fuel to their fire.
ryggesogn2
1 / 5 (1) Nov 06, 2011
That element of theory of science is new to me. Why should burden of proof depend on political persuasion?

Increasing socialism, more govt control of the world economy, is and has been the solution proposed by AGWites.
Why would 'scientists' support these solutions? Most scientists are state funded.
BTW, Popper was motivated by Marxists to develop falsification. Marxists couldn't do it and neither can AGWites.
Moebius
1 / 5 (1) Nov 06, 2011
Quite a controversy. Believers say that trillions of tons of added CO2 and other stuff due to our activities is starting to have dire effects. Skeptics think it all magically disappears with no effect and scientists don't know what they are talking about. Why are we even having this discussion?
Sigh
not rated yet Nov 06, 2011
That element of theory of science is new to me. Why should burden of proof depend on political persuasion?

Increasing socialism, more govt control of the world economy, is and has been the solution proposed by AGWites.
Why would 'scientists' support these solutions? Most scientists are state funded.
BTW, Popper was motivated by Marxists to develop falsification. Marxists couldn't do it and neither can AGWites.

I spent some time thinking, searching for a coherent answer to my question in this. Are you putting forward the "scientists (especially if state-funded) get more grant money for being alarmist, therefore nothing they warn about can be trusted" argument?
I hope not, because this is ridiculously broad and ignores all data. It is, quite ironically, unfalsifiable. It says the ozone hole doesn't exist or is natural (I saw that claim in a physorg comment recently), and the Newfoundland cod fishery never collapsed or if it did, it was not because of overfishing. And so on
ryggesogn2
1 / 5 (1) Nov 06, 2011
http://aetds.hnuc...9875.pdf
Are you putting forward the "scientists (especially if state-funded) get more grant money for being alarmist, therefore nothing they warn about can be trusted" argument?

Yes.
How many AGWites support market solutions such as nuclear power and natural gas instead of increasing the power of the state to control oil and coal?
Market based solutions to 'the commons' are well documented. How many support solutions based upon property rights?
Sigh
not rated yet Nov 06, 2011
Are you putting forward the "scientists (especially if state-funded) get more grant money for being alarmist, therefore nothing they warn about can be trusted" argument?

Yes.

Even though it is unfalsifiable when it gets applied recursively to anything that supports the original warning? It seems you really are serious in applying different standards of proof according to your interpretation of the politics.
How many AGWites support market solutions such as nuclear power

Reese Palley just published a book titled "The Answer", making just that case. I am sympathetic, but want a solution for neutron embrittlement. There are candidates, but nothing definite yet. Will you help fund research?

Another thing:
"Science is the belief in the ignorance of the experts", said Richard Feynman."
"So whats the problem? ...

You make this look as if you continued quoting Feynman. The source I found is Matt Ridley. It is important to attribute quotes to the correct sources.
Sigh
not rated yet Nov 06, 2011
Are you putting forward the "scientists (especially if state-funded) get more grant money for being alarmist, therefore nothing they warn about can be trusted" argument?

Yes.

I thought some more about this. You admit you rely on an unfalsifiable conspiracy theory to dismiss all conclusions of one particular type (environmental problem), and you implied you do so because you think the proposed solutions are always socialist.

The choice of action should always take costs and benefits into account, as well as the probabilities of various beliefs being true. If, however, you choose your beliefs based on perceived costs and benefits, you have left the realm of rationality and engage in wishful thinking.

That is the simplest interpretation of your words. I hope I'm wrong. Can you agree, explicitly and publicly, that only evidence and reasoning based on that evidence should play a role in choosing beliefs, and that costs and benefits are only relevant to choosing actions
Eric_B
not rated yet Nov 06, 2011
Someone should click "report abuse" so that RyggleTard might be forced to stop abusing the word, "socialism"!
ryggesogn2
1 / 5 (1) Nov 06, 2011
you think the proposed solutions are always socialist.

The proposed solutions ARE socialistic. They require govts confiscate private property.
Govt attempts to create an artificial market for carbon has collapsed enriching some like the politician/prophet Al Gore.
Is it a coincidence the proponents of AGW are funded by govt grants or work directly for govt agencies and propose govt regulatory solutions through an international political organization, IPCC?
And the 'solutions', like Solyndra are products of corrupt govt redistribution of wealth.
This IS called socialism, or legal plunder, by Bastiat, Mises,Hayek, ....
Sigh
not rated yet Nov 07, 2011
The proposed solutions ARE socialistic.

I already know that is your opinion, and it's a side issue.

I asked whether having demanded falsifiability of others, you really are content to use an unfalsifiable objection to dismiss all data you don't like. I asked whether you knowingly apply standards of proof to yourself that differ from the standards you apply to others. I asked whether you choose your beliefs based on the perceived costs and benefits of actions that might be based on those beliefs. All of this is compatible with what you wrote recently, but I might have misinterpreted you. I did once before. If I did interpret you correctly, you are not engaging in rational debate. Don't you think that is more important than whether I understood your definition of socialism, or whether it is consistent with Bastiat, Mises and Hayek?
Vendicar_Decarian
0 / 5 (34) Nov 14, 2011
"The proposed solutions ARE socialistic." - RyggTard

Social problems always are, since they must be solved with social policy.

Poor RyggTard. Couldn't purchase a clue if his pathetic life depended upon it.

"They require govts confiscate private property." - RyggTard

Ya, it's called taxation, and it a necessary component of Governance. You poor Tard you....

"And the 'solutions', like Solyndra are products of corrupt govt redistribution of wealth." - RyggTard

Sorry Tard Boy, there is nothing corrupt about it. Solyndra - - America's last hope for a domestic PV panel producer - was simply squashed like a bug by China.

More government support should have been provided to that startup company.

Unless of course you are one of the American Traitors who believes that America should be subservient to the Chinese.

OOh. I forgot... You are....

Vendicar_Decarian
0 / 5 (34) Nov 14, 2011
"... you are not engaging in rational debate." - Sigh

Don't expect Rational Debate from a Libertarian. Dishonesty and irrationality are their only stock and trade.

I have never encountered a Libertarian who wasn't a congenital and perpetual liar. RyggTard has proved itself to be no exception to that observation.