Climate Change: The Megathread - Read Post #1 before posting

Chloe Pink · 03-02-2013 12:13am

Macha wrote: »

Funny, I thought it was a pretty simple question.

It seems not ... I think it's called 'looking at the bigger picture'

Roger_007 · 03-02-2013 5:59pm

Macha wrote: »

Well then it becomes a question of what level of accuracy or probability you need in order to be spurred to take action?

The IPCC report includes an explanation of how they measure probability:
/QUOTE]

What is at stake here is a question of credibility as much as science. We have had too many examples of so-called experts misleading the public on important issues e.g. the various health scares we have had, the most recent of which was the swine flu debacle. It turned out to be no worse than ordinary seasonal flu despite all the dire warnings about mass deaths and economic damage. We also had all the economic experts telling us about how robust the economy and the banks were, just before the whole lot crashed.
When yet another bunch of experts come along with dire warnings about global warming, is it any wonder that many people are sceptical. That is why the IPCC are wrong to insist that they are 100% correct in their predictions. They cannot be 100% certain and they should be upfront about that. It would make their case more credible if they said there was an x% chance of something happening rather that saying that something WILL happen. The object should be to bring the people with you rather than preaching from on high.
They should also stop branding people who question their findings as 'unbelievers' and 'deniers'. We should not forget that that kind of language was used to discredit people like Galileo and Darwin in the past. The arguments should be debated on their merits without resorting to name-calling.

Macha · 03-02-2013 6:08pm

Roger_007 wrote: »

Macha wrote: »

Well then it becomes a question of what level of accuracy or probability you need in order to be spurred to take action?

The IPCC report includes an explanation of how they measure probability:
/QUOTE]

What is at stake here is a question of credibility as much as science. We have had too many examples of so-called experts misleading the public on important issues e.g. the various health scares we have had, the most recent of which was the swine flu debacle. It turned out to be no worse than ordinary seasonal flu despite all the dire warnings about mass deaths and economic damage. We also had all the economic experts telling us about how robust the economy and the banks were, just before the whole lot crashed.
When yet another bunch of experts come along with dire warnings about global warming, is it any wonder that many people are sceptical. That is why the IPCC are wrong to insist that they are 100% correct in their predictions. They cannot be 100% certain and they should be upfront about that. It would make their case more credible if they said there was an x% chance of something happening rather that saying that something WILL happen. The object should be to bring the people with you rather than preaching from on high.
They should also stop branding people who question their findings as 'unbelievers' and 'deniers'. We should not forget that that kind of language was used to discredit people like Galileo and Darwin in the past. The arguments should be debated on their merits without resorting to name-calling.

I think you're looking for something that you won't find if you want something that is 100% certain. Climate change is a theory in the same way gravity is a theory. In the case of both, it is the explanation that best fits the evidence we have.

We're not talking about mathematical equations here, we're talking about scientific theory.

Re Galileo and Darwin: their theories were based on empirical evidence. So is climate change. The IPCC reports are based on peer-reviewed academic research. I don't think the same could be said for the theories of those accusing Galileo and Darwin of heresy.

On economics, there's a reason it's called the dismal science!

Roger_007 · 03-02-2013 6:25pm

Macha wrote: »

Roger_007 wrote: »

I think you're looking for something that you won't find if you want something that is 100% certain. Climate change is a theory in the same way gravity is a theory. In the case of both, it is the explanation that best fits the evidence we have.

We're not talking about mathematical equations here, we're talking about scientific theory.

Re Galileo and Darwin: their theories were based on empirical evidence. So is climate change. The IPCC reports are based on peer-reviewed academic research. I don't think the same could be said for the theories of those accusing Galileo and Darwin of heresy.

On economics, there's a reason it's called the dismal science!

I never said I questioned the science which I am sure is as accurate as the data allows. What I question is the way it is presented. There is an arrogance in presentation which is designed to silence any reasonable questions, e.g. if the present concentration of CO2, (380ppm), in the atmosphere is too high, what is the 'right amount'? I have seen this question asked but never answered. Perhaps you know.

Macha · 03-02-2013 7:01pm

Roger_007 wrote: »

Macha wrote: »

I never said I questioned the science which I am sure is as accurate as the data allows. What I question is the way it is presented. There is an arrogance in presentation which is designed to silence any reasonable questions, e.g. if the present concentration of CO2, (380ppm), in the atmosphere is too high, what is the 'right amount'? I have seen this question asked but never answered. Perhaps you know.

OK I can see why it might come across as arrogance but seriously, there is no significant scientific debate about this anymore. It's also an incredibly urgent issue, with the International Energy Agency saying we need emissions to peak before 2020.

So when the media tries to pretend that there is some legitimate debate about the issue (because, well, otherwise there wouldn't be a story), I understand why those of us working to tackle climate action get impatient and annoyed.

In terms of the right concentration, the IPCC says 350 ppm is the maximum safe limit. So anything below 350 is much better than where we are today. You might be familiar with the grass roots organisation, 350.org, which is based around this premise.

Roger_007 · 03-02-2013 11:15pm

Macha wrote: »

Roger_007 wrote: »

OK I can see why it might come across as arrogance but seriously, there is no significant scientific debate about this anymore. It's also an incredibly urgent issue, with the International Energy Agency saying we need emissions to peak before 2020.

So when the media tries to pretend that there is some legitimate debate about the issue (because, well, otherwise there wouldn't be a story), I understand why those of us working to tackle climate action get impatient and annoyed.

In terms of the right concentration, the IPCC says 350 ppm is the maximum safe limit. So anything below 350 is much better than where we are today. You might be familiar with the grass roots organisation, 350.org, which is based around this premise.

You have certainly proved my case about arrogance by stating that.."there is no significant scientific debate about this anymore". How arrogant is that! In science there is never a point where the questioning stops. That is how progress is made. Even Einstein's theory of relativity is now being re-examined in the light of new discoveries. We only have any significant direct global climate measurements for the past 30 years or so. We only have direct measurements of any kind at all for about 150 years. These timescales are hardly even a blink of an eye in global climate study. How can any serious scientist be so arrogant as to state that we know it all now and the case is closed. The only thing we can say with any certainty is that we know very little.
The science is fine as far as it goes, it just doesn't go very far.

Macha · 03-02-2013 11:41pm

I said "significant" debate. When 97% of climate experts believe humans are causing climate change, that means there is not a lot of significant debate about the causes. If you want to dismiss that as arrogance, go right ahead.

A few posts ago, you said climate scientists would have more credibility if they said they were 100% certain about X or Y. Now, you're accusing any scientist of saying "case closed" of arrogance. I call bull.

Chloe Pink · 04-02-2013 1:02am

The article 'The Perils of Confirmation Bias' reflects Roger007's stance
http://www.thegwpf.org/content/uploads/;2012/10/Ridley-ConfirmationBias1.pdf
It's only a short article but it's main message is extracted below;

"The philosopher Karl Popper famously made the case that the distinguishing feature of a scientific theory is that it is falsifiable [capable of being tested]. Scientists set out to shoot down each other’s theories and only when they fail does a hypothesis become an accepted scientific fact. For some time it has been clear that is not how most climate scientists operate."

"The modus operandi of the Intergovernmental Panel on Climate Change (IPPC) has been to accumulate evidence to champion rather than challenge a hypothesis, namely that rising carbon dioxide levels will in future cause dangerous climate change."

"How is it possible for scientific theories occasionally to fall, and science to remain honest, if scientists champion ideas rather than challenge them? The answer, obviously, is that scientists challenge each other."

"Instead of this, anybody who champions one of these hypotheses is often accused of “denial” or of not “believing” in climate change, and frequently subjected to a surprising level of abuse."

"Climate scientists and their media champions equate such scepticism with scepticism about, say, the theory of evolution. Yet evolution is an explanation of facts; dangerous man-made climate change is a prediction about the future. Theories about the future are always less reliable than theories about the past."

I note that Dr Indur Goklany has jumped ship and is now on the Academic Advisory Council for the GWPF; he was a member of the US delegation that established the IPCC and helped develop its First Assessment Report. He subsequently served as an IPCC reviewer. Some of his concerns re the IPCC's approach are apparent from his other work e.g. He took part in the making of "Policy Peril: Why Global Warming Policies are More Dangerous than Global Warming Itself" http://en.wikipedia.org/wiki/Indur_M._Goklany

AngryHippie · 04-02-2013 1:39am

Having just read Dr Indur Goklany's article in the Korean times,there are a couple of flaws in his article:
1. He has blatantly ignored the issue of the finite resources of the planet
2. He has asserted that poverty is the problem, not population

Taking item 1 into consideration, and stating that as nations got more prosperous, their population growth slowed, and their environmental impact decreased...This is contradicting what he has stated.
If the population of the planet increases to 9 billion, there are simply not enough resources for everybody to be middle class, to care about the environment and to pay a tax that contributes to a reduction of pollution levels, ergo...population growth will not slow at this point.

"At least 80% of humanity lives on less than $10 a day"

http://www.globalissues.org/article/26/poverty-facts-and-stats

This page alone, turns his entire article out to be the load of tosh that it is.

The mere fact that he is employed by the GWPF should reduce their credibility and intentions.

Chloe Pink · 04-02-2013 8:59am

AngryHippie wrote: »

Having just read Dr Indur Goklany's article in the Korean times,there are a couple of flaws in his article:
1. He has blatantly ignored the issue of the finite resources of the planet
2. He has asserted that poverty is the problem, not population

Taking item 1 into consideration, and stating that as nations got more prosperous, their population growth slowed, and their environmental impact decreased...This is contradicting what he has stated.
If the population of the planet increases to 9 billion, there are simply not enough resources for everybody to be middle class, to care about the environment and to pay a tax that contributes to a reduction of pollution levels, ergo...population growth will not slow at this point.

"At least 80% of humanity lives on less than $10 a day"

http://www.globalissues.org/article/26/poverty-facts-and-stats

This page alone, turns his entire article out to be the load of tosh that it is.

Birth rates do decrease with prosperity; this is not the preserve of Dr Indur Goklany; others including WHO observe this is the case; these two links explain why:
http://www.globalissues.org/article/206/poverty-and-population-growth-lessons-from-our-own-past
http://www.sustainer.org/dhm_archive/index.php?display_article=vn126manupured

No energy source is finite, it's physics, even taking energy out of wind depletes the wind.
Wind turbines can also increase local surface temperatures:
http://www.nasa.gov/topics/earth/features/tx-wind-farm.html

SiegfriedsMum · 04-02-2013 10:10am

Macha wrote: »

Your response doesn't actually answer my question: what level of probability would be acceptable for you to agree with climate change action?

Sure, I know you may not have got the answer you wanted.

You can't tell us with any degree of accuracy what the temperature will be next week, let alone in a hundred years. You then want me to speculate on how accurate the predictions of others are in telling us what the temperature will be in 100 years, and based on their guesses you then want me to agree to "action" as if we, the human race, have the ability to control the climate.

Here is a question and one which I am going to guess you won't like:

The human population is now 7 billion and estimated to be 9 billion within 50 years. Can you tell me whether some westerners giving up their SUV's and driving Hybrids and adding in extra attic insulation to their homes will counterbalance the projected increase in population on the total CO2 emissions of the world?

And, if not, should we be really focusing our efforts on population control rather than less important issues?

I know those are leading questions, but they are there to make a not unimportant point. All those extra 2 billion humans will want to eat meat, will want to drive SUV's to the bottle bank, and will want better houses with air conditioning and heating and so and so on.

Macha wrote: »

So far, what I hear you saying is that you don't think anyone has done a good job on predictions. I would disagree. For example since the first IPCC report in 1990, it has predicted an average temperature increase of 0.15-0.3°C. The reality has turned out for 1990-2005, to be an average temperature increase of 0.2°C per decade. If anything, the accuracy of their predictions is being confirmed, not the other way around.

Can I ask why, in 2013, you have stopped at 2005? It seems an unusual and somewhat arbitary date to stop at.

Chloe Pink · 04-02-2013 10:38am

Macha wrote: »

97% of climate experts believe humans are causing climate change

This article looks at the source of the 97% figure:
http://wattsupwiththat.com/2012/07/18/what-else-did-the-97-of-scientists-say/"I wonder just how many politicians, environmentalists or scientists who use the phrase ’97% of scientists’ (or those who more carefully use ‘active climate scientists’) to give weight to their arguments regarding climate change to the public, have any idea of the actual source of this soundbite. Perhaps a few may say the ’Doran Survey’, which is the one of the most common references for this ’97% of active climate scientists’ phrase. In fact, the Doran EoS paper merely cites a MSc thesis for the actual source of this 97% figure and the actual survey.
“This was a very simplistic and biased questionnaire.”

Here are but just a few of many responses from scientists that actually took part in the survey, taken from the appendi of the MSc thesis:

“..scientific issues cannot be decided by a vote of scientists. A consensus is not, at any given time, a good predictor of where the truth actually resides..”

“..The “hockey stick” graph that the IPCC so touted has, it is my understanding, been debunked as junk science..”

“..I’m not sure what you are trying to prove, but you will undoubtably be able to prove your pre-existing opinion with this survey! I’m sorry I even started it!..”

Roger_007 · 04-02-2013 11:16am

Macha wrote: »

I said "significant" debate. When 97% of climate experts believe humans are causing climate change, that means there is not a lot of significant debate about the causes. If you want to dismiss that as arrogance, go right ahead.

A few posts ago, you said climate scientists would have more credibility if they said they were 100% certain about X or Y. Now, you're accusing any scientist of saying "case closed" of arrogance. I call bull.

I think you misunderstood what I said. I said that scientists would have more credibility if they did NOT claim to be 100% certain. All predictions should be qualified by stating that the data is incomplete and that unforeseen events can occur which render any prediction useless. In science no case is ever closed.

Duiske · 04-02-2013 3:17pm

Macha wrote: »

I said "significant" debate. When 97% of climate experts believe humans are causing climate change, that means there is not a lot of significant debate about the causes.

Macha, the figure of "97% climate experts" seems on the face of it to be pretty authoritative, and suggestive of a consensus. But do you know how that 97% figure was actually arrived at ?

djpbarry · 04-02-2013 4:00pm

Roger_007 wrote: »

We also had all the economic experts telling us about how robust the economy and the banks were, just before the whole lot crashed.

Actually, any economist with half a brain was screaming that Irish property was ridiculously over-valued and the Irish tax base was far too narrow. People just didn’t want to know – they were in denial.

Roger_007 wrote: »

In science there is never a point where the questioning stops. That is how progress is made.

If every scientist was to continuously question absolutely every established scientific consensus, nobody would ever get anything done. There comes a point when the data is solid enough, when one can be >99% confident in a conclusion, to move on.

Roger_007 wrote: »

I said that scientists would have more credibility if they did NOT claim to be 100% certain.

I don’t know of too many scientists who have ever claimed to be 100% certain about anything.

djpbarry · 04-02-2013 4:00pm

SiegfriedsMum wrote: »

You can't tell us with any degree of accuracy what the temperature will be next week...

With any degree of accuracy? I disagree.

Macha · 04-02-2013 4:08pm

Roger_007 wrote: »

I think you misunderstood what I said. I said that scientists would have more credibility if they did NOT claim to be 100% certain. All predictions should be qualified by stating that the data is incomplete and that unforeseen events can occur which render any prediction useless. In science no case is ever closed.

Wow, sorry. I totally misread your post. Sorry about that. I understand that science is never a closed case, which brings me back to my original question of how much certainty do you need before you take action? Using your logic, we would still be using asbestos in buildings, lead in petrol and the tobacco industry could still be arguing that the case is not closed on the link between cigarettes and human health.

In fact, history is littered with examples of us waiting too long or not applying the precautionary principle sufficiently and this has resulted in huge damage and costs. The European Environmental Agency just released a report on it, if you're interested:

http://www.eea.europa.eu/publications/late-lessons-2

Duiske wrote: »

Macha, the figure of "97% climate experts" seems on the face of it to be pretty authoritative, and suggestive of a consensus. But do you know how that 97% figure was actually arrived at ?

Well, that figure comes from a survey carried out of randomly selected members of the American Geophysical Union and American Meteorological Society.

Another interesting statistic is that no nation or international scientific body rejects the theory of man-made climate change.

Chloe Pink · 04-02-2013 6:21pm

Macha wrote: »

Well, that figure comes from a survey carried out of randomly selected members of the American Geophysical Union and American Meteorological Society.
Another interesting statistic is that no nation or international scientific body rejects the theory of man-made climate change.

Do you have a link please?

Duiske · 04-02-2013 6:53pm

Macha wrote: »

Well, that figure comes from a survey carried out of randomly selected members of the American Geophysical Union and American Meteorological Society.

Neither here nor there, but the survey was not specifically directed at members of the above though it's likely, given 90% of the invitees to the survey were US based, that the majority of respondents were connected to the AGU or AMS.

Anyway, invitations to participate in the survey were sent to 10,257 scientists working in the area of the Earth sciences at major universities, and state facilities like NASA, NOAA, USGS etc. It was a 9 question survey, designed to be completed in under 2 minutes. 7 of the question were for classification of respondents, ie, education, expertise, published work etc, and 2 questions dealt with Climate Change. The 2 questions were,

1. When compared with pre-1800s levels, do you think that mean global temperatures have generally risen, fallen, or remained relatively constant?

2. Do you think human activity is a significant contributing factor in changing
mean global temperatures?

Of the 10,257 invitees, 3,146 responded. Using the classification questions, the number of valid respondents was reduced by only including those who listed climate science as their area of expertise and had published more than 50% of their recent papers on the subject of climate change. This reduced the number to 79. Of these, 96.2% (76 of 79) answered “risen” to question 1 and 97.4% (75 of 77) answered yes to question 2.

So, we get the 97% figure from a survey of 79 climate scientists who were asked 2 questions, the answers to which prove nothing more than the fact that Global temperatures have risen over the past 200 years, and that humans can contribute to climate change. Even the most skeptical of scientists would agree that temps have risen and there is such a thing as the "Greenhouse Effect".

It was a meaningless survey.

Macha · 04-02-2013 8:43pm

Do you have a link? Because this report of the survey states that it was 489 individuals:

http://stats.org/stories/2008/global_warming_survey_apr23_08.html

AngryHippie · 04-02-2013 10:21pm

Chloe Pink wrote: »

Birth rates do decrease with prosperity; this is not the preserve of Dr Indur Goklany; others including WHO observe this is the case; these two links explain why:
http://www.globalissues.org/article/206/poverty-and-population-growth-lessons-from-our-own-past
http://www.sustainer.org/dhm_archive/index.php?display_article=vn126manupured

No energy source is finite, it's physics, even taking energy out of wind depletes the wind.
Wind turbines can also increase local surface temperatures:
http://www.nasa.gov/topics/earth/features/tx-wind-farm.html

I think you missed the point I was trying to make.

Birth rates to decrease with prosperity, but there is no indication that the vast majority of the population are ever going to achieve said "prosperity" if anything, the wealth gap will continue to widen as it has been doing.

I am aware of the lack of an infinite power source, but that being said, there are energy systems that are renewed naturally, solar being the most obvious one, hydro-electric (being renewed by precipitation on high ground) tidal and as you mentioned, wind.

No single one of these is going to be enough to fulfill the energy requirements globally, but a combination would certainly reduce our CO2 output.

All of these energy sources have some strengths and weaknesses, but there is no reason why exposure to the weaknesses cannot be minimized and the strengths exploited to take a step in the direction of a long-term sustainable power supply.

Macha · 04-02-2013 10:38pm

Just to preempt the predictible, this is not to turn into a discussion on the pros and cons of renewables.

AngryHippie · 04-02-2013 10:48pm

Okay then, is discussion of CO2 sources allowed ?;)

http://www.irishtimes.com/newspaper/breaking/2013/0204/breaking49.html

:rolleyes:

Duiske · 04-02-2013 11:01pm

Macha wrote: »

Do you have a link? Because this report of the survey states that it was 489 individuals:

http://stats.org/stories/2008/global_warming_survey_apr23_08.html

Appears to be two different survey's, though they both highlight 97% agreement on temperature increase. Makes you wonder though, who are the 3% of "scientists" who believe temperatures have not risen ?.

Can't access my own PC at the moment, but will put up a summary pdf tomorrow. I have a link to a copy of the study, but I'm unsure about posting it because as far as I can tell from the official link, the study (Doran/Zimmermann) is behind a paywall.

Macha · 04-02-2013 11:12pm

Yeah be careful about posting stuff behind a paywall..

Roger_007 · 04-02-2013 11:26pm

Duiske wrote: »

Appears to be two different survey's, though they both highlight 97% agreement on temperature increase. Makes you wonder though, who are the 3% of "scientists" who believe temperatures have not risen ?.

Can't access my own PC at the moment, but will put up a summary pdf tomorrow. I have a link to a copy of the study, but I'm unsure about posting it because as far as I can tell from the official link, the study (Doran/Zimmermann) is behind a paywall.

If Duiske is accurately reporting what questions the survey consisted of, then it really does not matter what the result was. It was so obviously designed to produce a predefined outcome that it has no relevance in the debate at all.

Macha · 04-02-2013 11:31pm

Roger_007 wrote: »

If Duiske is accurately reporting what questions the survey consisted of, then it really does not matter what the result was. It was so obviously designed to produce a predefined outcome that it has no relevance in the debate at all.

There were two different surveys. If you choose to believe him/her about the other one, go right ahead but that's not a very robust questioning methodology.

I don't think I've changed my signature since I joined Boards 8 years ago..

SiegfriedsMum · 05-02-2013 7:59pm

djpbarry wrote: »

With any degree of accuracy? I disagree.

Then I look forward to you telling us all what the temperature will be on, for example, February 14th at midday, and then we'll see after the event how accurate your prediction is.

Then,as for every science experiment, we'll repeat the same experiment for Feb 21st, Feb 28 and every week for, say 13 weeks, and then assess the results and see how accurate the 13 predictions a week in advance are.

Then, if you have been accurate to within, say 1°C, we can applaud your predictions, and hope the results are replicable.

Or would you rather set your own goals and tell us the parameters you'd prefer?

djpbarry · 05-02-2013 8:22pm

SiegfriedsMum wrote: »

Then, if you have been accurate to within, say 1°C...

Hang on there now - you said that temperatures could not be predicted with any degree of accuracy.

Duiske · 05-02-2013 10:07pm

Macha wrote: »

Do you have a link? Because this report of the survey states that it was 489 individuals:

http://stats.org/stories/2008/global_warming_survey_apr23_08.html

Link to summary of the Doran survey.

http://www.wright.edu/~guy.vandegrift/climateblog/s06/012009_Doran.pdf

Chloe Pink · 05-02-2013 10:21pm

Duiske wrote: »

Appears to be two different survey's, though they both highlight 97% agreement on temperature increase. Makes you wonder though, who are the 3% of "scientists" who believe temperatures have not risen ?.

Can't access my own PC at the moment, but will put up a summary pdf tomorrow. I have a link to a copy of the study, but I'm unsure about posting it because as far as I can tell from the official link, the study (Doran/Zimmermann) is behind a paywall.

I found this piece from UIC, University of Illinois at Chicago re the the Doran/Zimmerman study: the UIC is where Doran and Zimmerman hung out at the time of the survey.
http://tigger.uic.edu/~pdoran/012009_Doran_final.pdf
"In our survey, the most specialized and knowledgeable respondents (with regard to climate change) are those who listed climate science as their area of expertise and who also have published more than 50% of their recent peer-reviewed papers on the subject of climate change (79 individuals in total).

It's received a lot of criticism, just three examples here:
http://wattsupwiththat.com/2012/07/18/what-else-did-the-97-of-scientists-say/
http://www.fcpp.org/blog/climate-scientists-consensus-based-on-a-myth/
http://wattsupwiththat.com/2012/07/18/about-that-overwhelming-98-number-of-scientists-consensus/

Apparently the AGU, American Geophysical Union has a position statement on climate Change:
http://www.americanthinker.com/2012/12/the_american_geophysical_union_and_climate_hysteria.html

Re Macha's link,
The survey was a gallup survey conducted by Harris@interactive for Stats.
Stats say "A detailed description of the study’s methodology as well as that of the earlier Gallup survey is available on request."; until we have sight of this we've no idea what this survey is actually showing - can you help Macha.

However as Duiske has indirectly pointed out, why isn't the following 100% -
"Ninety-seven percent of the climate scientists surveyed believe “global average temperatures have increased” during the past century." - this isn't disputed (survey done in 2007).

Interstingly the survey found that:
"Only 29% express a “great deal of confidence” that scientists understand the size and extent of anthropogenic [human] sources of greenhouse gases,” "
and
"Overall, only 5% describe the study of global climate change as a “fully mature” science, but 51% describe it as “fairly mature,” while 40% see it as still an “emerging” science."
and
"However, over two out of three (69%) believe there is at least a 50-50 chance that the debate over the role of human activity in global warming will be settled in the next 10 to 20 years. "

Chloe Pink · 05-02-2013 10:40pm

Duiske wrote: »

Link to summary of the Doran survey.

http://www.wright.edu/~guy.vandegrift/climateblog/s06/012009_Doran.pdf

Same one I found! Sorry I was busy posting when you must have posted this - any way the 77 scientists are there.

Be good if Macha can get the methodology etc for the survey in the link he provided although it doesn't say that "97% of climate experts believe humans are causing climate change"

Macha · 20-08-2013 6:31pm

The latest IPCC report says: “It is extremely likely that human influence on climate caused more than half of the observed increase in global average surface temperature from 1951 to 2010.“There is high confidence that this has warmed the ocean, melted snow and ice, raised global mean sea level and changed some climate extremes in the second half of the 20th century.”

http://www.nytimes.com/2013/08/20/science/earth/extremely-likely-that-human-activity-is-driving-climate-change-panel-finds.html?src=me&ref=general&_r=0

The trend seems to be towards more and more certainty about man-made climate change.

Roger_007 · 21-08-2013 9:44am

Macha wrote: »

The latest IPCC report says: “It is extremely likely that human influence on climate caused more than half of the observed increase in global average surface temperature from 1951 to 2010.“There is high confidence that this has warmed the ocean, melted snow and ice, raised global mean sea level and changed some climate extremes in the second half of the 20th century.”

http://www.nytimes.com/2013/08/20/science/earth/extremely-likely-that-human-activity-is-driving-climate-change-panel-finds.html?src=me&ref=general&_r=0

The trend seems to be towards more and more certainty about man-made climate change.

The IPCC report has not been published or even finalised yet. I doubt if they would use terms such as "more than half", or "high confidence", (very unscientific). But lets wait and see what the final report says.

I think the IPCC or any other scientific body should be very wary of making any specific predictions which can turn out to be demonstrably untrue.

For example, in 2007 a prediction* made by a Professor Wieslaw Maslowski of the US Institute of Oceanology, that the Arctic would be ice-free in summer by 2013, has turned out to be complete hogwash. This prediction was widely cited and referred to in the 2007 IPCC report.

When you make predictions and they prove to be false your credibility is lost. This is particularly true if the prediction is supposed to have a scientific basis. I expect this IPCC report will be a bit more vague and hedged with enough ifs and buts to enable them to explain away any non-fulfilled prophesies in the future. In short, it will be more a political than a scientific document.

* http://news.bbc.co.uk/2/hi/science/nature/7139797.stm

djpbarry · 21-08-2013 9:58am

Roger_007 wrote: »

The IPCC report has not been published or even finalised yet. I doubt if they would use terms such as "more than half", or "high confidence", (very unscientific).

Scientists use such language all the time, but there is usually a measure of statistical significance associated with such terms. Previous IPCC reports have provided explanations of what constitutes "high confidence", "very likely", etc.

Roger_007 wrote: »

I think the IPCC or any other scientific body should be very wary of making any specific predictions which can turn out to be demonstrably untrue.

For example, in 2007 a prediction* made by a Professor Wieslaw Maslowski of the US Institute of Oceanology, that the Arctic would be ice-free in summer by 2013, has turned out to be complete hogwash. This prediction was widely cited and referred to in the 2007 IPCC report.

If every scientist stopped publishing their work in case it was subsequently found to be incorrect, science would grind to a halt.

Roger_007 · 21-08-2013 11:11am

djpbarry wrote: »

Scientists use such language all the time, but there is usually a measure of statistical significance associated with such terms. Previous IPCC reports have provided explanations of what constitutes "high confidence", "very likely", etc.
If every scientist stopped publishing their work in case it was subsequently found to be incorrect, science would grind to a halt.

Any person who calls themselves a scientist should not publish work on subjects where there is uncertainty without precisely quantifying that uncertainty and that it may not be correct at all because of that uncertainty. Even if there is a 90% probability that something will occur then there is a 10% probability that it will not occur.
The last IPCC report, (Fourth Assessment) concluded that sea levels would 'probably' rise by between 18cm and 59cm by the year 2100. There two problems with that conclusion:
1. By expressing it as a probability suggests that it may not occur at all.
2. By having a huge difference between the lower and higher estimate means that there is little likelihood that that the process of arriving at either figure is correct.

djpbarry · 21-08-2013 11:33am

Roger_007 wrote: »

The last IPCC report, (Fourth Assessment) concluded that sea levels would 'probably' rise by between 18cm and 59cm by the year 2100. There two problems with that conclusion:
1. By expressing it as a probability suggests that it may not occur at all.
2. By having a huge difference between the lower and higher estimate means that there is little likelihood that that the process of arriving at either figure is correct.

Your first point doesn't make any sense - no prediction can be made with 100% confidence.

Your second point makes even less sense - you don't like the result, therefore you dismiss the method? Besides, a spread of about 40cm for a prediction of sea level rises in roughly 90 years doesn't strike me as "huge" at all - perhaps you could provide us with your precise quantification of "huge"?

Macha · 21-08-2013 11:34am

Roger_007 wrote: »

Any person who calls themselves a scientist should not publish work on subjects where there is uncertainty without precisely quantifying that uncertainty and that it may not be correct at all because of that uncertainty. Even if there is a 90% probability that something will occur then there is a 10% probability that it will not occur.
The last IPCC report, (Fourth Assessment) concluded that sea levels would 'probably' rise by between 18cm and 59cm by the year 2100. There two problems with that conclusion:
1. By expressing it as a probability suggests that it may not occur at all.
2. By having a huge difference between the lower and higher estimate means that there is little likelihood that that the process of arriving at either figure is correct.

So what you say is firstly that scientists shouldn't publish work without quantifying the uncertainty around their results. Fair enough, insofar as it's possible (eg I can see issues with social sciences..).

But then you characterize the expression of a probability as high as 90% as a 'problem'. Why? What sort of probability would not present a 'problem' for you?

Roger_007 · 21-08-2013 6:38pm

djpbarry wrote: »

Your first point doesn't make any sense - no prediction can be made with 100% confidence.

Your second point makes even less sense - you don't like the result, therefore you dismiss the method? Besides, a spread of about 40cm for a prediction of sea level rises in roughly 90 years doesn't strike me as "huge" at all - perhaps you could provide us with your precise quantification of "huge"?

Of course you can make 100% accurate predictions. You can predict that full solar eclipses will occur at any point into the future and where on the earth's surface they can be observed. The whole chemical industry world is dependant on the fact that for precise inputs: ingredients, pressure, temperature, time etc, a precise outcome can be predicted. Probably the most famous scientific prediction was Halley predicting that a comet would appear 53 years before it did.
The prediction of sea-level rise ranging from the barely noticeable to the catastrophic is another way of saying 'we just don't know'. If we don't know the only honest conclusion is: 'Not possible to predict'.

Macha wrote: »

So what you say is firstly that scientists shouldn't publish work without quantifying the uncertainty around their results. Fair enough, insofar as it's possible (eg I can see issues with social sciences..).

But then you characterize the expression of a probability as high as 90% as a 'problem'. Why? What sort of probability would not present a 'problem' for you?

A probability is just that, something which may happen or may not. Expressing it that way is an acknowledgement of the fact that certainty cannot be assured usually due to unknown factors or undue complexity .

Akrasia · 21-08-2013 7:38pm

Roger_007 wrote: »

Of course you can make 100% accurate predictions. You can predict that full solar eclipses will occur at any point into the future and where on the earth's surface they can be observed. The whole chemical industry world is dependant on the fact that for precise inputs: ingredients, pressure, temperature, time etc, a precise outcome can be predicted. Probably the most famous scientific prediction was Halley predicting that a comet would appear 53 years before it did.

The prediction of sea-level rise ranging from the barely noticeable to the catastrophic is another way of saying 'we just don't know'. If we don't know the only honest conclusion is: 'Not possible to predict'.

A probability is just that, something which may happen or may not. Expressing it that way is an acknowledgement of the fact that certainty cannot be assured usually due to unknown factors or undue complexity .

This is just one logical fallacy after another.

Just because scientists can make predictions about phenomenon X with a 99.99% confidence doesn't mean that predictions about a different more complex phemonenon that carry only a 50% confidence are not valid predictions.

Lets imagine that there is a hurricane brewing in the Atlantic and the NOAA have been tracking the storm over a 5-7 day period. They can make predictions that there is perhaps a 60% chance that the storm will strike New Orleans and a 60% chance that the storm will be sufficiently powerful to breach the storm defences.

Would you dismiss this prediction and oppose any attempt to evacuate the city of prepare for disaster on the basis that the prediction did not carry 100% certainty?

You'd be a fool to ignore the warnings and even if the storm turns out to be a false alarm and it doesn't make landfall or weakens, the prediction was still the best that the collected efforts of the worlds scientists could provide with the best technology available to them at the time.

You're comparing apples and oranges here. Predicting the orbit of celestial bodies using Newtownian theories of gravity is orders of magnitude more precise than predicting how a complex system will behave a century into the future.

There are multiple models all interacting and uncertainties within each one leads to a wide range of possible outcomes, but the prediction follows a probability curve. Some outcomes are very unlikely, and some outcomes are much more likely, but the scientists will publish their data honestly and provide detailed probability statistics for each possible outcome.

The Media of course will over simplify things and the climate change deniers will distort the findings and the cranks will make up their own predictions with far higher 'confidence' levels which will make it look like the real scientists are just hedging their bets.

djpbarry · 22-08-2013 9:25am

Roger_007 wrote: »

The whole chemical industry world is dependant on the fact that for precise inputs: ingredients, pressure, temperature, time etc, a precise outcome can be predicted.

In that case, what does any company need with quality control?

Roger_007 wrote: »

The prediction of sea-level rise ranging from the barely noticeable to the catastrophic is another way of saying 'we just don't know'.

18cm is barely noticeable, but 59cm is catastrophic?

Anyways, you may be interested to know about a recent paper, which illustrates that the future global mean temperature trend predicted in the first IPCC report, way back in 1990, has so far proved to be very accurate:
http://dx.doi.org/10.1038/nclimate1763

Chloe Pink · 29-08-2013 8:19pm

Before touting statements from some leaked not yet published IPCC report, it might be good if those who touted "97% of climate scientists" on this thread could provide the basis for this figure as requested earlier.

In the meantime, here's one persons view of the IPCC and one I tend to agree with
http://www.quadrant.org.au/blogs/doomed-planet/2013/08/the-95-certainty-is-that-the-ipcc-can-t-be-trusted
"Consider that claim of "95% certainty", which is no more than an opinion expressed by a few IPCC authors and approved by a few others. It has no basis in mathematics or statistics and might just as well have been have been plucked from thin air, which may indeed have been the case."

djpbarry · 08-09-2013 10:58am

Chloe Pink wrote: »

In the meantime, here's one persons view of the IPCC and one I tend to agree with
http://www.quadrant.org.au/blogs/doomed-planet/2013/08/the-95-certainty-is-that-the-ipcc-can-t-be-trusted
"Consider that claim of "95% certainty", which is no more than an opinion expressed by a few IPCC authors and approved by a few others. "

So the overwhelming majority of authors and reviewers of the latest IPCC report disagree with this assertion? Got anything to support that?

Akrasia · 11-09-2013 11:18am

There's a very good article here
http://www.yaleclimatemediaforum.org/2013/09/examining-the-recent-slow-down-in-global-warming/
which looks at the different models and temperature records for the various parts of the planet and asks why the temperature increase appears to have slowed down in the last decade and what implications this has for future model predictions.

Here's my summary:
While there is a slowdown in temperature increases, most of the earths systems are still experiencing temperature growth.
There has been a reduction in sea surface temperatures over the past 10 years, but this has been more than offset by the deep sea temperature rises which are capable of holding vast amounts of heat energy.

The overall long term temperature trends are still on an upward trajectory but the next decade will enable us to refine our calculations for what the climate sensitivity really is and enable us to make better predictions.

theLegion · 25-09-2013 12:10pm

Akrasia wrote: »

There's a very good article here
http://www.yaleclimatemediaforum.org/2013/09/examining-the-recent-slow-down-in-global-warming/
which looks at the different models and temperature records for the various parts of the planet and asks why the temperature increase appears to have slowed down in the last decade and what implications this has for future model predictions.

Here's my summary:
While there is a slowdown in temperature increases, most of the earths systems are still experiencing temperature growth.
There has been a reduction in sea surface temperatures over the past 10 years, but this has been more than offset by the deep sea temperature rises which are capable of holding vast amounts of heat energy.

The overall long term temperature trends are still on an upward trajectory but the next decade will enable us to refine our calculations for what the climate sensitivity really is and enable us to make better predictions.

What an absolute fcuk-up:

Leaked IPCC Report

‘Surface temperature reconstructions show multi-decadal intervals during the Medieval Climate Anomaly (950-1250) that were in some regions as warm as in the late 20th Century.’

http://www.telegraph.co.uk/earth/environment/climatechange/10310712/Top-climate-scientists-admit-global-warming-forecasts-were-wrong.html

http://www.sciencedirect.com/science/article/pii/S0277379104002367

Opps

I look forward to the publication of the report, I hope the railroad engineer didn't throw out his choo choo trains.

Akrasia · 25-09-2013 12:32pm

So the best that the climate deniers can come up with is a graph that still shows that the world has warmed by almost half a degree celsius in only 30 years?

The IPCC 4th assessment prediction was that global warming would increase global average temperatures by about .2 degrees per decade. Meanwhile the global warming deniers were predicting an ice age.

The trend continues upwards. While real scientists are trying to improve our understanding and make better predictions, the denier community are looking to score political points and anomaly hunting

If you read the link i posted above, you will see that the actual rate of global warming is still uncertain because we can not say for certain how much warming has been absorbed by the deep oceans (deep ocean warming is still warming).

PercyBlakeney · 25-09-2013 12:34pm

Unfortunately, those who believe in GW keep shooting themselves in the foot and making claims which later turn out to be untrue, or are based on such flimsy evidence that one has to wonder at the impartiality of their position.

For example, it was claimed by the IPCC that the Himalayan glaciers would be melted by 2035. It later transpired their “evidence” for making such a claim was no more than a wildly inaccurate pamphlet produced by one activist. In the wake of the scandal, the IPCC had to withdraw its claim, although why it made the claim in the first place seems to suggest an agenda.

This month, September 2013, was supposed to be the month the Artic was “Ice free” or so we were told back in 2007. It’s not ice free, far from it, and has pretty much the same ice as has been average for the past 35 years.

Then we had all the computer models with all their predictions, and yet temperatures have not risen as predicted in the past 17 years.

Facts are facts. Predictions are not facts.

djpbarry · 25-09-2013 12:35pm

theLegion wrote: »

What an absolute fcuk-up:

So, the actual recorded temperature was within the range predicted? How does that constitute a ****-up?

djpbarry · 25-09-2013 12:54pm

PercyBlakeney wrote: »

For example, it was claimed by the IPCC that the Himalayan glaciers would be melted by 2035. It later transpired their “evidence” for making such a claim was no more than a wildly inaccurate pamphlet produced by one activist. In the wake of the scandal, the IPCC had to withdraw its claim, although why it made the claim in the first place seems to suggest an agenda.

And yet, six years on from its publication, no further evidence of an agenda has been found. The reasonable conclusion is that it was an isolated mistake.

PercyBlakeney wrote: »

This month, September 2013, was supposed to be the month the Artic was “Ice free” or so we were told back in 2007. It’s not ice free, far from it, and has pretty much the same ice as has been average for the past 35 years.

Really?

PercyBlakeney wrote: »

Then we had all the computer models with all their predictions, and yet temperatures have not risen as predicted in the past 17 years.

Really?

Akrasia · 25-09-2013 1:39pm

PercyBlakeney wrote: »

Unfortunately, those who believe in GW keep shooting themselves in the foot and making claims which later turn out to be untrue, or are based on such flimsy evidence that one has to wonder at the impartiality of their position.

For example, it was claimed by the IPCC that the Himalayan glaciers would be melted by 2035. It later transpired their “evidence” for making such a claim was no more than a wildly inaccurate pamphlet produced by one activist. In the wake of the scandal, the IPCC had to withdraw its claim, although why it made the claim in the first place seems to suggest an agenda.

This month, September 2013, was supposed to be the month the Artic was “Ice free” or so we were told back in 2007. It’s not ice free, far from it, and has pretty much the same ice as has been average for the past 35 years.

Then we had all the computer models with all their predictions, and yet temperatures have not risen as predicted in the past 17 years.

Facts are facts. Predictions are not facts.

It's funny how 'those who believe in global warming' are held responsible for every single claim ever made by anyone who believes in AGW
If you can find any mistakes by anyone on this side, that means that nobody can be trusted and all of the evidence must be wrong

On the other hand, you do not hold the opponents of the global warming hypothesis to anywhere near the same standard. One error is enough to destroy the credibility of the entire scientific community, but global warming deniers can flat out lie and deliberately distort the evidence, but the 'climate sceptics' openly question the credibility of their own statistics or arguments.

You are cherry picking errors and claims and only discussing data that you think supports your pre-existing opinion.

'Glaciergate' boils down to one source in one volume of a 3 volume publication with tens of thousands of scientific references getting into the final draft of the paper without it being fully verified first.

This error was discovered by the scientific community themselves (better late than never) and of the thousands of other sources that 'sceptics' have been scrutinising since, looking to discredit the IPCC, the vast majority of them are valid and represent the best most rigorous science available at the time.

The claim about the Arctic Sea ice was not a claim that the arctic will definitely be ice free in 2013, it was a claim that the summer Ice 'could' have disappeared in 2013 if certain conditions had been met. It wasn't a prediction with a high level of confidence, and the vast majority of scientists didn't agree that it was likely. However, the vast majority of scientists do agree that a few decades, we will see ice free summers in the Arctic.

What do the climate change 'sceptics' predict about arctic sea ice?

Climate Change: The Megathread - Read Post #1 before posting

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