More bad poll news for the k00ks!!!

Hell, I still want to what happened to that damn Ice Age we were promised back in the early seventies.

The nutters were promisin' it, but where did it go?

What up wit dat chit?
 
You have just made the ultimate mistake my friend. You rely on the alarmists climate models and they can't re-create the weather that occured 5 days ago. The models are completely incapable of accurately recreating what we know occured.

In the scientiic community following the Scientific Principle the computer model is the hypothesis. It has been tested and it has failed every time it has been tried. That means the hypothsis itself is a failure. It does not accurately represent what is observed in the actual wolrd. No climate model is capable of predicting even the simplest sequence of events for a period of one week.

They all fail miserably. Until they can create a model that can do just the simplest re-creation of past weather or climate there is zero chance they can predict the future. An intelligent person can understand that.

As usual, you're quite deluded and quite wrong. This is another one of the myths of your denier cult that you all accept as gospel but that really has no connection to reality.

How Well Do Coupled Models Simulate Today's Climate?
Bulletin of the American Meteorological Society

March 2008
Dr. Thomas Reichler, Associate Professor - Department of Atmospheric Sciences
and
Junsu Kim
Department of Meteorology, University of Utah, Salt Lake City, Utah

Abstract

Information about climate and how it responds to increased greenhouse gas concentrations depends heavily on insight gained from numerical simulations by coupled climate models. The confidence placed in quantitative estimates of the rate and magnitude of future climate change is therefore strongly related to the quality of these models. In this study, we test the realism of several generations of coupled climate models, including those used for the 1995, 2001, and 2007 reports of the Intergovernmental Panel on Climate Change (IPCC). By validating against observations of present climate, we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere.



Climate Models & Accuracy
(excerpt)

3 - These models are able to simulate past climate. According to the IPCC (2007): "Models have been used to simulate ancient climates, such as the warm mid-Holocene of 6,000 years ago or the last glacial maximum of 21,000 years ago. They can reproduce many features (allowing for uncertainties in reconstructing past climates) such as the magnitude and broad-scale pattern of oceanic cooling during the last ice age. Models can also simulate many observed aspects of climate change over the instrumental record. One example is that the global temperature trend over the past century (shown in Figure 6.2) can be modelled with high skill when both human and natural factors that influence climate are included. Models also reproduce other observed changes, such as the faster increase in nighttime than in daytime temperatures, the larger degree of warming in the Arctic and the small, short-term global cooling (and subsequent recovery) which has followed major volcanic eruptions, such as that of Mt. Pinatubo in 1991. Model global temperature projections made over the last two decades have also been in overall agreement with subsequent observations over that period."

climate_model_ensembles.gif

Figure 6.1: Global temperature trend over the past century modeled quite well
 
Hell, I still want to what happened to that damn Ice Age we were promised back in the early seventies.

The nutters were promisin' it, but where did it go?

What up wit dat chit?

LOLOLOL....did you just fall off the turnip truck or something? Where you been, boy? Are you going to try out every one of the debunked denier cult propaganda memes on us? LOL.

OK, just this once because you're so amusingly naive and clueless.

Study debunks 'global cooling' concern of '70s
By Doyle Rice
USA TODAY
2/22/2008
(short excerpt - see main article for much more)

The supposed "global cooling" consensus among scientists in the 1970s — frequently offered by global-warming skeptics as proof that climatologists can't make up their minds — is a myth, according to a survey of the scientific literature of the era.

The '70s was an unusually cold decade. Newsweek, Time, The New York Times and National Geographic published articles at the time speculating on the causes of the unusual cold and about the possibility of a new ice age.

But Thomas Peterson of the National Climatic Data Center surveyed dozens of peer-reviewed scientific articles from 1965 to 1979 and found that only seven supported global cooling, while 44 predicted warming. Peterson says 20 others were neutral in their assessments of climate trends.

The study reports, "There was no scientific consensus in the 1970s that the Earth was headed into an imminent ice age. A review of the literature suggests that, to the contrary, greenhouse warming even then dominated scientists' thinking about the most important forces shaping Earth's climate on human time scales."

"I was surprised that global warming was so dominant in the peer-reviewed literature of the time," says Peterson


Copyright 2011 USA TODAY, a division of Gannett Co. Inc.

(In accordance with Title 17 U.S.C. Section 107, this material is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes.)
 
You have just made the ultimate mistake my friend. You rely on the alarmists climate models and they can't re-create the weather that occured 5 days ago. The models are completely incapable of accurately recreating what we know occured.

In the scientiic community following the Scientific Principle the computer model is the hypothesis. It has been tested and it has failed every time it has been tried. That means the hypothsis itself is a failure. It does not accurately represent what is observed in the actual wolrd. No climate model is capable of predicting even the simplest sequence of events for a period of one week.

They all fail miserably. Until they can create a model that can do just the simplest re-creation of past weather or climate there is zero chance they can predict the future. An intelligent person can understand that.

As usual, you're quite deluded and quite wrong. This is another one of the myths of your denier cult that you all accept as gospel but that really has no connection to reality.

How Well Do Coupled Models Simulate Today's Climate?
Bulletin of the American Meteorological Society

March 2008
Dr. Thomas Reichler, Associate Professor - Department of Atmospheric Sciences
and
Junsu Kim
Department of Meteorology, University of Utah, Salt Lake City, Utah

Abstract

Information about climate and how it responds to increased greenhouse gas concentrations depends heavily on insight gained from numerical simulations by coupled climate models. The confidence placed in quantitative estimates of the rate and magnitude of future climate change is therefore strongly related to the quality of these models. In this study, we test the realism of several generations of coupled climate models, including those used for the 1995, 2001, and 2007 reports of the Intergovernmental Panel on Climate Change (IPCC). By validating against observations of present climate, we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere.



Climate Models & Accuracy
(excerpt)

3 - These models are able to simulate past climate. According to the IPCC (2007): "Models have been used to simulate ancient climates, such as the warm mid-Holocene of 6,000 years ago or the last glacial maximum of 21,000 years ago. They can reproduce many features (allowing for uncertainties in reconstructing past climates) such as the magnitude and broad-scale pattern of oceanic cooling during the last ice age. Models can also simulate many observed aspects of climate change over the instrumental record. One example is that the global temperature trend over the past century (shown in Figure 6.2) can be modelled with high skill when both human and natural factors that influence climate are included. Models also reproduce other observed changes, such as the faster increase in nighttime than in daytime temperatures, the larger degree of warming in the Arctic and the small, short-term global cooling (and subsequent recovery) which has followed major volcanic eruptions, such as that of Mt. Pinatubo in 1991. Model global temperature projections made over the last two decades have also been in overall agreement with subsequent observations over that period."

climate_model_ensembles.gif

Figure 6.1: Global temperature trend over the past century modeled quite well




BATTER UP!


BTW the first one is from a warmist alarmist.....

"Some models suggest very strongly that the American Southwest will dry in a warming world; some models suggest that the Sahel will dry in a warming world. But other models suggest the exact opposite. Now, let's just imagine that the models have an equal pedigree in terms of the scientists who have worked on them and in terms of the papers that have been published — it's not quite true but it's a good working assumption. With these two models, you have two estimates — one says it's going to get wetter and one says it's going to get drier. What do you do? Is there anything that you can say at all? That is a really difficult question.
...
The problem with climate prediction and projections going out to 2030 and 2050 is that we don't anticipate that they can be tested in the way you can test a weather forecast. It takes about 20 years to evaluate because there is so much unforced variability in the system which we can't predict — the chaotic component of the climate system — which is not predictable beyond two weeks, even theoretically. That is something that we can't really get a handle on.
...
Freeman Dyson has made a critique of models. I don't know Freeman Dyson; I've met his children. He seems like a very smart person. He has done some very interesting physics. He seems like a guy I would like to know. Yet his statements about climate, climate models, climate modelers, Jim Hansen in particular, are not the statements you would expect a smart person to make. It's like Shakespeare writing a play and then pulling a quote from a penny dreadful sheet that he found in the street. It just seems very inconsistent that somebody who thinks so hard and is so smart about so many things says dumb things like, oh, climate modelers think that their models are real and can't see the real world. I paraphrase but he said something very similar. It betrays a complete ignorance of either climate modelers, climate models or what it is that climate science is all about. His statements about Jim Hansen were very similar."


Edge: THE PHYSICS THAT WE KNOW: A Conversation With Gavin Schmidt

Junk Science Week: MIT

http://carbon-sense.com/wp-content/uploads/2010/05/dice-games.pdf

C3: Climate Models
 
As usual, you're quite deluded and quite wrong. This is another one of the myths of your denier cult that you all accept as gospel but that really has no connection to reality.

As usual, your beliefs have little to do with reality. Here is some peer reviewed science regarding climate models for you to chew on.

A comparison of local and aggregated climate model outputs with observed data - Hydrological Sciences Journal

A comparison of tropical temperature trends with model predictions - Douglass - 2007 - International Journal of Climatology - Wiley Online Library

[0905.0445] An updated comparison of model ensemble and observed temperature trends in the tropical troposphere

Altitude dependence of atmospheric temperature trends: Climate models versus observation

Multi-Science Publishing - Journal Article

Do deep ocean temperature records verify models?

Phys. Rev. Lett. 89, 028501 (2002): Global Climate Models Violate Scaling of the Observed Atmospheric Variability

Inter Research » CR » v18 » n3 » p259-275

AMS Journals Online - Potential Biases in Feedback Diagnosis from Observational Data: A Simple Model Demonstration

Seductive Simulations? Uncertainty Distribution Around Climate Models

ScienceDirect - Applied Energy : Shortcomings of CO2-climate models raise questions about the wisdom of energy policy implications

SpringerLink - Pure and Applied Geophysics, Volume 135, Number 1

There are plenty more if you care to look. Ever notice how it is the skeptics who back their arguments with actual published, peer reviewed data as opposed to the blogs that you guys so depend on?
 
So glad some of the Repugs love polls so much..

Gallup poll: John Boehner's favorable numbers slide

House Speaker John Boehner has become less popular with Americans across the political spectrum since taking the gavel in January.

A USA Today/Gallup Poll released Wednesday showed that 56 percent of Republicans view him favorably, down from 65 percent in January.

Among independents, his net favorable ratings are down a whopping 27 percentage points. About 29 percent of independents said they hold a favorable view of the speaker.

And 46 percent of Democrats find him unfavorable, up from 34 percent.

“The Speaker is focused on the big challenges facing our country — and, thus far, the Democrats who still run Washington seem more focused on partisan attacks that real solutions,” Boehner’s spokesman Michael Steel said in response to the numbers.

In the first four months of his term as speaker of the House, the Ohio Republican has been through several epic battles, including a number of short-term government funding measures, extending the Patriot Act and shepherding through a controversial 2012 spending blueprint.

Overall, the poll said that Boehner’s favorable/unfavorable ratings are identical: 34 percent of Americans see him favorably, and 34 see him unfavorably. In January — the last time Gallup polled — 42 percent of people saw him favorably, nearly double the 22 who had the opposite view.

Read more: Gallup poll: John Boehner's favorable numbers slide - Jake Sherman - POLITICO.com
 
House Speaker John Boehner, a day after saying Congress should consider scaling back tax breaks for big oil companies, appeared to reel in that political olive branch Tuesday as the White House and congressional Democrats seized on his remarks.

The Republican speaker at first seemed to open the door to negotiations with Democrats, saying in an interview Monday that lawmakers "ought to take a look" at President Obama's call to save billions by ending those benefits.

Not surprisingly, the White House and its allies applauded Boehner and urged his colleagues to follow suit. Obama fired off a letter Tuesday to congressional leaders saying he was "heartened" to hear Boehner's comments and called for "immediate action to eliminate unwarranted tax breaks for the oil and gas industry" -- a tax trove he values at $4 billion a year.

But Boehner's office pushed back Tuesday, suggesting the speaker wants to see a more comprehensive approach before signing on to any changes.

"The speaker wants to increase the supply of American energy and reduce our dependence on foreign oil, and he is only interested in reforms that actually lower energy costs and create American jobs," spokesman Brendan Buck said in a statement. "Unfortunately, what the president has suggested so far would simply raise taxes and increase the price at the pump."

The response came as Democrats accompanied the White House letter with a string of backhanded compliments.

Sen. Chuck Schumer, D-N.Y., said it was "almost too good to be true" that Boehner realized the "insanity" of giving oil companies tax breaks while gas prices are soaring. He and other Senate Democrats meanwhile slammed rank-and-file Republicans for standing by the "giveaways."

Boehner Plays Down Oil Subsidy Remarks After Dems Seize on Interview - FoxNews.com

That's Republican "leadership" for you.. Taking their ques from the teapartiers on every issue.
 
Seeing is always believing with humans. At one time, the worlds population believed the earth was flat too. and that the sun rotated around the earth.

I'm glad you didn't get roped into the propaganda of inevitable climate shift though. :lmao:

Yes, seeing is believing. And I have seen nearly seven decades on this planet. I have seen major changes in what grows at what altitudes in the mountains of Oregon and Washington. I have seen the shrinking of the glaciers in the Cascades, Sierras, Rockies, and ever ealier melts in the Blues.

Many people that I know whose career is in geological fields have witnessed first hand the melting of the Arctic Ice and Permafrost.

Seeing is not believing for all too many here who purposely close their eyes to the changes around them in order to maintain their alternative universe version of reality.

One of the problems I have with this issue is, had you been here for the past seven million decades, you would have seen considerably more (and much more drastic) change to those same places you mentioned because climate change is also a naturally occurring thing. So, to me, this issue is about how much control over our lives we should be willing to cede to these scientists and politicians (who have a huge stake in the movement).

And I don’t buy into the notion that we are entitled to keep everything exactly the way it is right now simply because we like it (or are used to it) that way. Nope, if the polar bears (or human beings) can’t survive on the earth that evolves tomorrow, they simply have to wind up in the same place as so many other species that could not keep up wound up. That’s nature’s way and, regardless of what we (who are here only at this one instant in time) might want, we can’t stop it.
 
Kids...the climate doesn't CARE what you or I think is happening.

A POLL doesn't dictate reality.

Believe whatever the hell you want, the climate will do what it must.
 
Seeing is always believing with humans. At one time, the worlds population believed the earth was flat too. and that the sun rotated around the earth.

I'm glad you didn't get roped into the propaganda of inevitable climate shift though. :lmao:

Yes, seeing is believing. And I have seen nearly seven decades on this planet. I have seen major changes in what grows at what altitudes in the mountains of Oregon and Washington. I have seen the shrinking of the glaciers in the Cascades, Sierras, Rockies, and ever ealier melts in the Blues.

Many people that I know whose career is in geological fields have witnessed first hand the melting of the Arctic Ice and Permafrost.

Seeing is not believing for all too many here who purposely close their eyes to the changes around them in order to maintain their alternative universe version of reality.

One of the problems I have with this issue is, had you been here for the past seven million decades, you would have seen considerably more (and much more drastic) change to those same places you mentioned because climate change is also a naturally occurring thing. So, to me, this issue is about how much control over our lives we should be willing to cede to these scientists and politicians (who have a huge stake in the movement).

And I don’t buy into the notion that we are entitled to keep everything exactly the way it is right now simply because we like it (or are used to it) that way. Nope, if the polar bears (or human beings) can’t survive on the earth that evolves tomorrow, they simply have to wind up in the same place as so many other species that could not keep up wound up. That’s nature’s way and, regardless of what we (who are here only at this one instant in time) might want, we can’t stop it.



Hey Rockhead............I saw that your state gave the Cap and Trade legislation the big old kick in the ass back in February. I thinking the vote was 246-104............very comforting to know!!!:clap2:


Welcome aboard Rockhead...........and c'mon back in real soon. This place is a hoot if you want to be a part of publically humiliating far left asshole environmental k00ks. What makes it even more fun is that these jarheads get humiliated on a daily basis and keep coming back. IM telling you........its a hoot.


Anyway.........your point is so spot on its almost laughable. In fact, it is laughable.........and to think. The nutters on here actually think humans have to power to control nature. Its fascinating.........but also proof that these folks have a significant amount of mental fcukkedupedness going on in the old nogin. This is the Jim Jones crowd but the potion here is this bogus science.



jonestown.jpg




If Gore said to drink the red stuff ^^^^^^^^^^^^^
 
Last edited:
You have just made the ultimate mistake my friend. You rely on the alarmists climate models and they can't re-create the weather that occured 5 days ago. The models are completely incapable of accurately recreating what we know occured.

In the scientiic community following the Scientific Principle the computer model is the hypothesis. It has been tested and it has failed every time it has been tried. That means the hypothsis itself is a failure. It does not accurately represent what is observed in the actual wolrd. No climate model is capable of predicting even the simplest sequence of events for a period of one week.

They all fail miserably. Until they can create a model that can do just the simplest re-creation of past weather or climate there is zero chance they can predict the future. An intelligent person can understand that.

As usual, you're quite deluded and quite wrong. This is another one of the myths of your denier cult that you all accept as gospel but that really has no connection to reality.

How Well Do Coupled Models Simulate Today's Climate?
Bulletin of the American Meteorological Society

March 2008
Dr. Thomas Reichler, Associate Professor - Department of Atmospheric Sciences
and
Junsu Kim
Department of Meteorology, University of Utah, Salt Lake City, Utah

Abstract

Information about climate and how it responds to increased greenhouse gas concentrations depends heavily on insight gained from numerical simulations by coupled climate models. The confidence placed in quantitative estimates of the rate and magnitude of future climate change is therefore strongly related to the quality of these models. In this study, we test the realism of several generations of coupled climate models, including those used for the 1995, 2001, and 2007 reports of the Intergovernmental Panel on Climate Change (IPCC). By validating against observations of present climate, we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere.



Climate Models & Accuracy
(excerpt)

3 - These models are able to simulate past climate. According to the IPCC (2007): "Models have been used to simulate ancient climates, such as the warm mid-Holocene of 6,000 years ago or the last glacial maximum of 21,000 years ago. They can reproduce many features (allowing for uncertainties in reconstructing past climates) such as the magnitude and broad-scale pattern of oceanic cooling during the last ice age. Models can also simulate many observed aspects of climate change over the instrumental record. One example is that the global temperature trend over the past century (shown in Figure 6.2) can be modelled with high skill when both human and natural factors that influence climate are included. Models also reproduce other observed changes, such as the faster increase in nighttime than in daytime temperatures, the larger degree of warming in the Arctic and the small, short-term global cooling (and subsequent recovery) which has followed major volcanic eruptions, such as that of Mt. Pinatubo in 1991. Model global temperature projections made over the last two decades have also been in overall agreement with subsequent observations over that period."

climate_model_ensembles.gif

Figure 6.1: Global temperature trend over the past century modeled quite well

BATTER UP!
Is this what you say every time you get your ass kicked? LOL.


BTW the first one is from a warmist alarmist.....

"Some models suggest very strongly that the American Southwest will dry in a warming world; some models suggest that the Sahel will dry in a warming world. But other models suggest the exact opposite. Now, let's just imagine that the models have an equal pedigree in terms of the scientists who have worked on them and in terms of the papers that have been published — it's not quite true but it's a good working assumption. With these two models, you have two estimates — one says it's going to get wetter and one says it's going to get drier. What do you do? Is there anything that you can say at all? That is a really difficult question.
...
The problem with climate prediction and projections going out to 2030 and 2050 is that we don't anticipate that they can be tested in the way you can test a weather forecast. It takes about 20 years to evaluate because there is so much unforced variability in the system which we can't predict — the chaotic component of the climate system — which is not predictable beyond two weeks, even theoretically. That is something that we can't really get a handle on.
...
Freeman Dyson has made a critique of models. I don't know Freeman Dyson; I've met his children. He seems like a very smart person. He has done some very interesting physics. He seems like a guy I would like to know. Yet his statements about climate, climate models, climate modelers, Jim Hansen in particular, are not the statements you would expect a smart person to make. It's like Shakespeare writing a play and then pulling a quote from a penny dreadful sheet that he found in the street. It just seems very inconsistent that somebody who thinks so hard and is so smart about so many things says dumb things like, oh, climate modelers think that their models are real and can't see the real world. I paraphrase but he said something very similar. It betrays a complete ignorance of either climate modelers, climate models or what it is that climate science is all about. His statements about Jim Hansen were very similar."


Edge: THE PHYSICS THAT WE KNOW: A Conversation With Gavin Schmidt
Yeah, so??? So what, walleyed? It's a climate scientist discussing the complexities and difficulties of modeling the climate. This is not a secret. The fact remains that the current models have gotten very good at accurately modeling past climates and predicting future developments. As the recent paper that studies modeling results that I just cited says: "...we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere."

Gavin Schmidt also says in this article you're quoting:
"We have been quite successful at building these models on the basis of small-scale processes to produce large-scale simulation of the emerging properties of the climate system. We understand why we have a seasonal cycle; we understand why we have storms in the mid-latitudes; we understand what controls the ebb and flow of the seasonal sea ice distribution in the Arctic. We have good estimates in this regard....It turns out that the average of these twenty models is a better model than any one of the twenty models. It better predicts the seasonal cycle of rainfall; it better predicts surface air temperatures; it better predicts cloudiness."



LOLOLOLOL.....let me get this straight....I cite a peer reviewed paper published in a climate related scientific journal - the Bulletin of the American Meteorological Society, written by a professional climate scientist and professor in the Department of Atmospheric Sciences at a major University, that directly studies models and their accuracy and concludes that they are pretty accurate....and you try to refute that with an (non-peer-reviewed) article in the Financial Post written by two guys who are definitely not climate scientists - Kesten C. Green who has a degree in Management Science and J. Scott Armstrong, a professor of Marketing at the Wharton School with degrees in industrial administration and management - who claim that the models are no good. LOLOLOL. Dr. Armstrong was so sure of himself that in 2007 he offered to bet Al Gore $10,000 that temperatures would not increase in the next ten years. Then, in the real world - 2009 was tied for the second warmest year in the modern record, a new NASA analysis of global surface temperature shows. & According to NOAA scientists, 2010 tied with 2005 as the warmest year of the global surface temperature record, beginning in 1880. From the Wikipedia page on Armstrong: "Climatologist Gavin Schmidt described Armstrong's wager as "essentially a bet on year to year weather noise" rather than on climate change.[17] Armstrong's website, which had been declaring monthly and yearly "winners" of the hypothetical bet, stopped updating the status of the "bet" in March 2010, after Armstrong had lost six of the seven months prior. He has since lost his bet for April, May, June, and July 2010, making Armstrong the loser for 2010 as a whole."

There was a published rebuttal in the journal Interfaces to Armstrong and Green's articles that said: "Green and Armstrong (2007, p.997) also concluded that the thousands of refereed scientific publications that comprise the basis of the IPCC reports and represent the state of scientific knowledge on past, present and future climates "were not the outcome of scientific procedures." Such cavalier statements appear to reflect an overt attempt by the authors of those reports to cast doubt about the reality of human-caused global warming ... ".



Sorry bozo, I never open pdf files from denier cult blogs. Quote from it if you want but, considering the source, it's almost certainly just more denier cult drivel and pseudo-science anyway.



This has got to be the funniest one of all your "rebuttals". Perhaps in your case we should call them "re-buttheads". 'C3' is a denier cult blog and it is as wacked out wrong as the rest of them. On the page you cited they say: "...the empirical evidence is clear that atmospheric water vapor component is not increasing with an upward trend as predicted by IPCC's climate models and their Climategate scientists. At best, water vapor content has remained constant with the distinct possibility it has trended down over recent years."

The reality: Increase in Atmospheric Moisture Tied to Human Activities, published in 2009 in the Proceedings of the U.S. National Academy of Sciences.
(excerpt)

Observations and climate model results confirm that human-induced warming of the planet is having a pronounced effect on the atmosphere’s total moisture content.

“When you heat the planet, you increase the ability of the atmosphere to hold moisture,” said Benjamin Santer, lead author from Lawrence Livermore National Laboratory’s Program for Climate Modeling and Intercomparison. “The atmosphere’s water vapor content has increased by about 0.41 kilograms per square meter (kg/m²) per decade since 1988, and natural variability in climate just can’t explain this moisture change. The most plausible explanation is that it’s due to the human-caused increase in greenhouse gases.”

Using 22 different computer models of the climate system and measurements from the satellite-based Special Sensor Microwave Imager (SSM/I), atmospheric scientists from LLNL and eight other international research centers have shown that the recent increase in moisture content over the bulk of the world’s oceans is not due to solar forcing or gradual recovery from the 1991 eruption of Mount Pinatubo. The primary driver of this ‘atmospheric moistening’ is the increase in carbon dioxide caused by the burning of fossil fuels.

Basic theory, observations and climate model results all show that the increase in water vapor is roughly 6 percent to 7.5 percent per degree Celsius warming of the lower atmosphere.
 
Last edited:
What, no Ice Age?

Damn, I was lookin' forward to some serious snow boardin' action.

Were the nutters just lyin' to us?

Seems to be a pattern with those junk science eatin' idiots.

But then hey, those morons believe anything Algore tells 'em so, we shouldn't really be surprised.
 
What, no Ice Age?

Damn, I was lookin' forward to some serious snow boardin' action.

Were the nutters just lyin' to us?

Seems to be a pattern with those junk science eatin' idiots.

But then hey, those morons believe anything Algore tells 'em so, we shouldn't really be surprised.
Is your brain asleep or are you just really retarded? I just debunked your nonsense in post #83. Most scientists considered AGW the problem, not cooling, even back in the 70's. Try to keep up as best you can, numbnuts.
 
What, no Ice Age?

Damn, I was lookin' forward to some serious snow boardin' action.

Were the nutters just lyin' to us?

Seems to be a pattern with those junk science eatin' idiots.

But then hey, those morons believe anything Algore tells 'em so, we shouldn't really be surprised.
Is your brain asleep or are you just really retarded? I just debunked your nonsense in post #83. Most scientists considered AGW the problem, not cooling, even back in the 70's. Try to keep up as best you can, numbnuts.
Most scientists?.........Yeah, ok!

Would those "most" scientists be the ones who completely blew you loons and your fantasies out the water through exposed E-mails admitting it's all a fraud?

Or were they the "most" scientists who got caught lying about the Himalayan glaciers?

Oooooooooor, could they be the "most" scientists who went through Algore's fiasco of a film and debunked it point by point?
 
even Trenberth admits that the GCMs will have increased uncertainty once they start adding more factors like clouds, etc
 
As usual, you're quite deluded and quite wrong. This is another one of the myths of your denier cult that you all accept as gospel but that really has no connection to reality.

How Well Do Coupled Models Simulate Today's Climate?
Bulletin of the American Meteorological Society

March 2008
Dr. Thomas Reichler, Associate Professor - Department of Atmospheric Sciences
and
Junsu Kim
Department of Meteorology, University of Utah, Salt Lake City, Utah

Abstract

Information about climate and how it responds to increased greenhouse gas concentrations depends heavily on insight gained from numerical simulations by coupled climate models. The confidence placed in quantitative estimates of the rate and magnitude of future climate change is therefore strongly related to the quality of these models. In this study, we test the realism of several generations of coupled climate models, including those used for the 1995, 2001, and 2007 reports of the Intergovernmental Panel on Climate Change (IPCC). By validating against observations of present climate, we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere.



Climate Models & Accuracy
(excerpt)

3 - These models are able to simulate past climate. According to the IPCC (2007): "Models have been used to simulate ancient climates, such as the warm mid-Holocene of 6,000 years ago or the last glacial maximum of 21,000 years ago. They can reproduce many features (allowing for uncertainties in reconstructing past climates) such as the magnitude and broad-scale pattern of oceanic cooling during the last ice age. Models can also simulate many observed aspects of climate change over the instrumental record. One example is that the global temperature trend over the past century (shown in Figure 6.2) can be modelled with high skill when both human and natural factors that influence climate are included. Models also reproduce other observed changes, such as the faster increase in nighttime than in daytime temperatures, the larger degree of warming in the Arctic and the small, short-term global cooling (and subsequent recovery) which has followed major volcanic eruptions, such as that of Mt. Pinatubo in 1991. Model global temperature projections made over the last two decades have also been in overall agreement with subsequent observations over that period."

climate_model_ensembles.gif

Figure 6.1: Global temperature trend over the past century modeled quite well

BATTER UP!
Is this what you say every time you get your ass kicked? LOL.



Yeah, so??? So what, walleyed? It's a climate scientist discussing the complexities and difficulties of modeling the climate. This is not a secret. The fact remains that the current models have gotten very good at accurately modeling past climates and predicting future developments. As the recent paper that studies modeling results that I just cited says: "...we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere."

Gavin Schmidt also says in this article you're quoting:
"We have been quite successful at building these models on the basis of small-scale processes to produce large-scale simulation of the emerging properties of the climate system. We understand why we have a seasonal cycle; we understand why we have storms in the mid-latitudes; we understand what controls the ebb and flow of the seasonal sea ice distribution in the Arctic. We have good estimates in this regard....It turns out that the average of these twenty models is a better model than any one of the twenty models. It better predicts the seasonal cycle of rainfall; it better predicts surface air temperatures; it better predicts cloudiness."




LOLOLOLOL.....let me get this straight....I cite a peer reviewed paper published in a climate related scientific journal - the Bulletin of the American Meteorological Society, written by a professional climate scientist and professor in the Department of Atmospheric Sciences at a major University, that directly studies models and their accuracy and concludes that they are pretty accurate....and you try to refute that with an (non-peer-reviewed) article in the Financial Post written by two guys who are definitely not climate scientists - Kesten C. Green who has a degree in Management Science and J. Scott Armstrong, a professor of Marketing at the Wharton School with degrees in industrial administration and management - who claim that the models are no good. LOLOLOL. Dr. Armstrong was so sure of himself that in 2007 he offered to bet Al Gore $10,000 that temperatures would not increase in the next ten years. Then, in the real world - 2009 was tied for the second warmest year in the modern record, a new NASA analysis of global surface temperature shows. & According to NOAA scientists, 2010 tied with 2005 as the warmest year of the global surface temperature record, beginning in 1880. From the Wikipedia page on Armstrong: "Climatologist Gavin Schmidt described Armstrong's wager as "essentially a bet on year to year weather noise" rather than on climate change.[17] Armstrong's website, which had been declaring monthly and yearly "winners" of the hypothetical bet, stopped updating the status of the "bet" in March 2010, after Armstrong had lost six of the seven months prior. He has since lost his bet for April, May, June, and July 2010, making Armstrong the loser for 2010 as a whole."

There was a published rebuttal in the journal Interfaces to Armstrong and Green's articles that said: "Green and Armstrong (2007, p.997) also concluded that the thousands of refereed scientific publications that comprise the basis of the IPCC reports and represent the state of scientific knowledge on past, present and future climates "were not the outcome of scientific procedures." Such cavalier statements appear to reflect an overt attempt by the authors of those reports to cast doubt about the reality of human-caused global warming ... ".



Sorry bozo, I never open pdf files from denier cult blogs. Quote from it if you want but, considering the source, it's almost certainly just more denier cult drivel and pseudo-science anyway.



This has got to be the funniest one of all your "rebuttals". Perhaps in your case we should call them "re-buttheads". 'C3' is a denier cult blog and it is as wacked out wrong as the rest of them. On the page you cited they say: "...the empirical evidence is clear that atmospheric water vapor component is not increasing with an upward trend as predicted by IPCC's climate models and their Climategate scientists. At best, water vapor content has remained constant with the distinct possibility it has trended down over recent years."

The reality: Increase in Atmospheric Moisture Tied to Human Activities, published in 2009 in the Proceedings of the U.S. National Academy of Sciences.
(excerpt)

Observations and climate model results confirm that human-induced warming of the planet is having a pronounced effect on the atmosphere’s total moisture content.

“When you heat the planet, you increase the ability of the atmosphere to hold moisture,” said Benjamin Santer, lead author from Lawrence Livermore National Laboratory’s Program for Climate Modeling and Intercomparison. “The atmosphere’s water vapor content has increased by about 0.41 kilograms per square meter (kg/m²) per decade since 1988, and natural variability in climate just can’t explain this moisture change. The most plausible explanation is that it’s due to the human-caused increase in greenhouse gases.”

Using 22 different computer models of the climate system and measurements from the satellite-based Special Sensor Microwave Imager (SSM/I), atmospheric scientists from LLNL and eight other international research centers have shown that the recent increase in moisture content over the bulk of the world’s oceans is not due to solar forcing or gradual recovery from the 1991 eruption of Mount Pinatubo. The primary driver of this ‘atmospheric moistening’ is the increase in carbon dioxide caused by the burning of fossil fuels.

Basic theory, observations and climate model results all show that the increase in water vapor is roughly 6 percent to 7.5 percent per degree Celsius warming of the lower atmosphere.





No, I use BATTER UP! when I'm going to partuicularly blast one of you or olfrauds ridiculous assertions out of the park. You claim that they have computer models that can recreate the past weather. Please provide a link to that assertion.
 
That's your delusion because you're the fool. Scientists know better. Even scientists who dispute AGW know better.

Dr. Roy Spencer who runs the satellite monitoring program at the University of Alabama Huntsville, is a skeptic of AGW, one of the very few actual climate scientists who's still skeptical, and here's what he has to say about CO2 and the greenhouse effect.

And yet, he can't offer up any proof that he is right. He has attempted experiments to prove backradiation but they have all failed. He states that he believes it even though he can't prove it.

The greenhouse effect is supported by laboratory measurements of the radiative absorption properties of different gases, which when put into a radiative transfer model that conserves energy, and combined with convective overturning of the atmosphere in response to solar heating, results in a vertical temperature profile that looks very much like the one we observe in nature.


***

Translate = models tell us it is true so it must be true. There is no proof there. All that statement says is that your "scientists" have faith in models and we all know that the models are notoriously inaccurate.

By the way, the vertical temperature profile produced by models your "scientist" speaks of is not at all like the vertical temperature profile observed in nature as evidenced by the missing hot spot that all models predict.

I also want to add this, which I spotted in another quote here and then we shall address both statements here, and place the cross-hairs squarely on target, all You have to do is squeeze the trigger afterwards...

How Well Do Coupled Models Simulate Today's Climate?
Bulletin of the American Meteorological Society
March 2008
Dr. Thomas Reichler, Associate Professor - Department of Atmospheric Sciences
and
Junsu Kim
Department of Meteorology, University of Utah, Salt Lake City, Utah

Abstract

Information about climate and how it responds to increased greenhouse gas concentrations depends heavily on insight gained from numerical simulations by coupled climate models. The confidence placed in quantitative estimates of the rate and magnitude of future climate change is therefore strongly related to the quality of these models. In this study, we test the realism of several generations of coupled climate models, including those used for the 1995, 2001, and 2007 reports of the Intergovernmental Panel on Climate Change (IPCC). By validating against observations of present climate,.....

I clipped the statement and will put the rest of this statement in all fairness inside quote html tags after I finished and You can judge for Yourself to see if the rest was true ...

Most Americans have absolved at least high school and do in fact know the difference between linear and non linear functions..
Some have not and don`t know,... except making retard remarks , we all know who they are, and their re(tard)marks will surely follow ....

All functions where Y is directly or even just indirectly proportional to X are linear functions...no matter if Y= simply X, or Y= 2times X, or Y= Z*X/2, or Y= X * Z-whatever...each of these are linear no matter how complex You make the expression.

So if on any graph the "average global temperature" follows the Carbon di-Oxide concentration then the person who plotted this graph has stated that the temperature was in a DIRECTLY LINEAR PROPORTION with the CO2 concentration...there is no way out of this noose...so let`s pick up the loose end and pull it tight right now :


globalTempCO2.gif


as You can see he plotted it, choosing the scale for each so that Temperature increase matches exactly CO2 ppm...in other words he just made the statement that Y=X...

This guy wanted to add a point on top of it all and chose a 2.5 times larger scale for his temperature to "show" how CO2 will cook this planet..:

historical03.gif


But to conceal it he did not make it Y=X times 2.5...he also stayed with Y=X

And so far with no exception every "climate scientist" has been using this as empirical "proof" that it is CO2 driving the temperature and not anything else, because of this simple proportionality in any of these graphs they fabricate and as they also say...that if they plug in the radiative "forcing effect" of CO2 into their "climate computer model" they have a good match...and this is why I sat on the last part of the quote till I got to this point..:

In this study, we test the realism of several generations of coupled climate models, including those used for the 1995, 2001, and 2007 reports of the Intergovernmental Panel on Climate Change (IPCC). By validating against observations of present climate, we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere.


So now let`s tie up the loose end to something more solid and get on with the business at hand...

Radiative forcing - Wikipedia, the free encyclopedia

IPCC usage

The term “radiative forcing” has been used in the IPCC Assessments with a specific technical meaning, to denote an externally imposed perturbation in the radiative energy budget of Earth’s climate system, which may lead to changes in climate parameters.[1] The exact definition used is:

The radiative forcing of the surface-troposphere system due to the perturbation in or the introduction of an agent (say, a change in greenhouse gas concentrations) is the change in net (down minus up) irradiance (solar plus long-wave; in Wm-2) at the tropopause AFTER allowing for stratospheric temperatures to readjust to radiative equilibrium, but with surface and tropospheric temperatures and state held fixed at the unperturbed values.[2]


Then they revised it...:

In a subsequent report,[3] the IPCC defines it as:

"Radiative forcing is a measure of the influence a factor has in altering the balance of incoming and outgoing energy in the Earth-atmosphere system and is an index of the importance of the factor as a potential climate change mechanism. In this report radiative forcing values are for changes relative to preindustrial conditions defined at 1750 and are expressed in watts per square meter (W/m2)."

In simple terms, radiative forcing is "...the rate of energy change per unit area of the globe as measured at the top of the atmosphere."[4] In the context of climate change, the term "forcing" is restricted to changes in the radiation balance of the surface-troposphere system imposed by external factors, with no changes in stratospheric dynamics, no surface and tropospheric feedbacks in operation (i.e., no secondary effects induced because of changes in tropospheric motions or its thermodynamic state), and no dynamically induced changes in the amount and distribution of atmospheric water (vapour, liquid, and solid forms).

Radiative forcing can be used to estimate a subsequent change in equilibrium surface temperature (ΔTs) arising from that radiative forcing via the equation:
74945338ec357d4a68e5f5356f8f19a0.png

They should have never published this equation

All it takes is just a few minutes to write a short little program which shows that they DON NOT EVEN APPLY THEIR OWN OVERSIMPLIFIED EQUATION in any of these graphs where they wish to show that CO2 concentration and temperature are directly PROPORTIONAL, because this is no longer a LINEAR FUNCTION...
The reason why they don`t employ this equation when it comes to making these grossly falsified graphs showing a connection between CO2 & Temperature they CAN`T AFFORD TO USE THIS EQUATION, BECAUSE THE calculated RADIATIVE FORCING EFFECT using their own equation dives way down from the "average temperatures" they claim to have measured..:

TCO2Composite.jpg


WindowHeight = 800
WindowWidth = 1000
UpperLeftX = 150
UpperLeftY = 25
open "graph" for graphics as #h
startred=1000:startblue=669:c2=330:c1=c2
limit=1000
for c1=c2 to limit
'display both functions from 330 to 1000 ppm CO2
[calculateWatts A sNatural Log (ln) function of CO2 concentration ratio]
' REMARK the synthax for ln is log, in any programming language the
'synthax log IS NOT the base 10 decade log

df=5.35*log(c1/c2)
[calculate Watts/m^2 Aslinear CO2 Function]
gosub [graph]
'graph linear as red ;graph Natural Log (ln)function as blue
next c1
gosub [vertical]
wait
[graph]
'mag=50
mag=53.5: x1=c1-279:x2=x1
y2=mag*df:y2=startblue-y2:y1=y2-1
print #h,"size 2"
print #h,"color blue"
print #h, "down"
print #h, "line ";x1;" ";y1;" ";x2;" ";y2
print #h, "flush "
print #h,"color red"
y2=startred-co2
y1=y2-1
print #h, "down"
print #h, "line ";x1;" ";y1;" ";x2;" ";y2
print #h, "flush "
return
[vertical]
x1=50:y1=startblue:y2=10:x2=x1
print #h,"color black"
print #h, "down"
print #h, "line ";x1;" ";y1;" ";x2;" ";y2
print #h, "flush "
x1=662:y1=startblue:y2=10:x2=x1
print #h,"color black"
print #h, "down"
print #h, "line ";x1;" ";y1;" ";x2;" ";y2
print #h, "flush "
'vertical calibration divisions
x1=50:x2=700:yscale=6.1
for z=0 to 100 step 10
y=startblue-(z*yscale)
y1=y:y2=y
print #h,"color black"
print #h, "down"
print #h, "line ";x1;" ";y1;" ";x2;" ";y2
print #h, "flush "
next z
'horizontal calibration divisions
xscale=6.1:y1=startblue:y2=startblue-611
b=50
for z1=0 to 100 step 10
d=b+(z1*xscale):x1=d:x2=d
print #h,"color black"
print #h, "down"
print #h, "line ";x1;" ";y1;" ";x2;" ";y2
print #h,"flush "
next z1
return


The blue line is what You would get if You did apply their equation, but for all the temperature graphs they had to straight-line it and simply made Temperature proportional to CO2 ppm as in Y=X

What does the "radiative forcing Watts per squ.- meter" have to do with temperature, You may ask,...
Well the mass of the earth`s atmosphere stays constant and if You increase the Watts which are 0.24 calories per second for each Watt then that translates instantly to temperature increase per second by dividing the Watts by the specific heat or 1 Cubic meter air

Even the milk maid math Glow Ball graph fabricators realized that and pushed
74945338ec357d4a68e5f5356f8f19a0.png
aside for Y=X, where Y is the "average temperature" they claimed to have measured and X the ppm CO2 as per Mona Lua

But that`s not all they have simplified...take a look at the rest of their "Global Warming Math"...:

Radiative forcing - Wikipedia, the free encyclopedia

..... For the case of a change in solar irradiance, the radiative forcing is the change in the solar constant divided by 4 and multiplied by 0.7 to take into account the geometry of the sphere and the amount of reflected sunlight.

So solar radiation is a constant...and not a factor at all and simply by diminishing that "none factor" this huge nuclear reactor we call our sun further down to 70% which in their pea brains takes care of "the geometry of the earth...


So Yes of course they would have to keep insisting that solar activity has next to no effect on THEIR "average global temperature" when compared to the "radiative forcing effect of man made greenhouse gasses".....

And that`s the operative here "THEIR" world...which has absolutely nothing to do with the real world


Like most here said all along, this is what we are dealing with here...:


dodo%20flat%20earth%202.jpg
;
globalTempCO2.gif


To quote Westwall..:
strike 3..Next batter up

Except that baseball is not really a German thing...
and anyone striking out playing games with us, The words "NEXT UP !!!" are to be understood quite literally .German is a very unambiguous language
and we do insist on the true meanings of words !!

images



And I `m an old fashioned German
 
Last edited:
BATTER UP!
Is this what you say every time you get your ass kicked? LOL.



Yeah, so??? So what, walleyed? It's a climate scientist discussing the complexities and difficulties of modeling the climate. This is not a secret. The fact remains that the current models have gotten very good at accurately modeling past climates and predicting future developments. As the recent paper that studies modeling results that I just cited says: "...we show that the coupled models have been steadily improving over time and that the best models are converging toward a level of accuracy that is similar to observation-based analyses of the atmosphere."

Gavin Schmidt also says in this article you're quoting:
"We have been quite successful at building these models on the basis of small-scale processes to produce large-scale simulation of the emerging properties of the climate system. We understand why we have a seasonal cycle; we understand why we have storms in the mid-latitudes; we understand what controls the ebb and flow of the seasonal sea ice distribution in the Arctic. We have good estimates in this regard....It turns out that the average of these twenty models is a better model than any one of the twenty models. It better predicts the seasonal cycle of rainfall; it better predicts surface air temperatures; it better predicts cloudiness."




LOLOLOLOL.....let me get this straight....I cite a peer reviewed paper published in a climate related scientific journal - the Bulletin of the American Meteorological Society, written by a professional climate scientist and professor in the Department of Atmospheric Sciences at a major University, that directly studies models and their accuracy and concludes that they are pretty accurate....and you try to refute that with an (non-peer-reviewed) article in the Financial Post written by two guys who are definitely not climate scientists - Kesten C. Green who has a degree in Management Science and J. Scott Armstrong, a professor of Marketing at the Wharton School with degrees in industrial administration and management - who claim that the models are no good. LOLOLOL. Dr. Armstrong was so sure of himself that in 2007 he offered to bet Al Gore $10,000 that temperatures would not increase in the next ten years. Then, in the real world - 2009 was tied for the second warmest year in the modern record, a new NASA analysis of global surface temperature shows. & According to NOAA scientists, 2010 tied with 2005 as the warmest year of the global surface temperature record, beginning in 1880. From the Wikipedia page on Armstrong: "Climatologist Gavin Schmidt described Armstrong's wager as "essentially a bet on year to year weather noise" rather than on climate change.[17] Armstrong's website, which had been declaring monthly and yearly "winners" of the hypothetical bet, stopped updating the status of the "bet" in March 2010, after Armstrong had lost six of the seven months prior. He has since lost his bet for April, May, June, and July 2010, making Armstrong the loser for 2010 as a whole."

There was a published rebuttal in the journal Interfaces to Armstrong and Green's articles that said: "Green and Armstrong (2007, p.997) also concluded that the thousands of refereed scientific publications that comprise the basis of the IPCC reports and represent the state of scientific knowledge on past, present and future climates "were not the outcome of scientific procedures." Such cavalier statements appear to reflect an overt attempt by the authors of those reports to cast doubt about the reality of human-caused global warming ... ".




Sorry bozo, I never open pdf files from denier cult blogs. Quote from it if you want but, considering the source, it's almost certainly just more denier cult drivel and pseudo-science anyway.



This has got to be the funniest one of all your "rebuttals". Perhaps in your case we should call them "re-buttheads". 'C3' is a denier cult blog and it is as wacked out wrong as the rest of them. On the page you cited they say: "...the empirical evidence is clear that atmospheric water vapor component is not increasing with an upward trend as predicted by IPCC's climate models and their Climategate scientists. At best, water vapor content has remained constant with the distinct possibility it has trended down over recent years."

The reality: Increase in Atmospheric Moisture Tied to Human Activities, published in 2009 in the Proceedings of the U.S. National Academy of Sciences.
(excerpt)

Observations and climate model results confirm that human-induced warming of the planet is having a pronounced effect on the atmosphere’s total moisture content.

“When you heat the planet, you increase the ability of the atmosphere to hold moisture,” said Benjamin Santer, lead author from Lawrence Livermore National Laboratory’s Program for Climate Modeling and Intercomparison. “The atmosphere’s water vapor content has increased by about 0.41 kilograms per square meter (kg/m²) per decade since 1988, and natural variability in climate just can’t explain this moisture change. The most plausible explanation is that it’s due to the human-caused increase in greenhouse gases.”

Using 22 different computer models of the climate system and measurements from the satellite-based Special Sensor Microwave Imager (SSM/I), atmospheric scientists from LLNL and eight other international research centers have shown that the recent increase in moisture content over the bulk of the world’s oceans is not due to solar forcing or gradual recovery from the 1991 eruption of Mount Pinatubo. The primary driver of this ‘atmospheric moistening’ is the increase in carbon dioxide caused by the burning of fossil fuels.

Basic theory, observations and climate model results all show that the increase in water vapor is roughly 6 percent to 7.5 percent per degree Celsius warming of the lower atmosphere.


No, I use BATTER UP! when I'm going to partuicularly blast one of you or olfrauds ridiculous assertions out of the park.
I'm afraid that you're getting all delusional on me again, walleyed. You've never managed to successfully refute any of the scientific information that I've posted, except maybe in your own very confused and delusion brain (what there is of it).


You claim that they have computer models that can recreate the past weather. Please provide a link to that assertion.
Nice try, slick, but no, I've said that computer models can accurately model past climate patterns not past day-to-day weather. So either you were trying to set up a 'strawman argument' like you usually do when you don't have a leg to stand on, or you just don't know enough about modeling to know that 'climate modeling' specifically deals with longer term trends in global and regional climate patterns over longer periods of years, decades, centuries and millennia and these trends can be accurately modeled. On a shorter time scale of weeks or months, the factors tend to be too chaotic for accurate modeling. As it happens, as climate models have developed and improved due to the intense research into all the different physical factors involved, the knowledge gained has bled over into significant improvements in the computer models that meteorologists use for weather forecasting so that forecasts have gotten more accurate and longer range over recent decades.

Here's some confirmation of the fact that climate models can accurately model past climate patterns. The chart and the paragraphs above and below are the most relevant but I'm going to include the whole article so you can see that the limitations and errors in the models are recognized and understood but don't overwhelm the basic overall ability of the models to accurately reflect both past and current climate changes and also because this material is freely available for reproduction and is not under copyright restrictions.

How Reliable Are the Models Used to Make Projections of Future Climate Change?

There is considerable confidence that climate models provide credible quantitative estimates of future climate change, particularly at continental scales and above. This confidence comes from the foundation of the models in accepted physical principles and from their ability to reproduce observed features of current climate and past climate changes. Confidence in model estimates is higher for some climate variables (e.g., temperature) than for others (e.g., precipitation). Over several decades of development, models have consistently provided a robust and unambiguous picture of significant climate warming in response to increasing greenhouse gases.

Climate models are mathematical representations of the climate system, expressed as computer codes and run on powerful computers. One source of confidence in models comes from the fact that model fundamentals are based on established physical laws, such as conservation of mass, energy and momentum, along with a wealth of observations.

A second source of confidence comes from the ability of models to simulate important aspects of the current climate. Models are routinely and extensively assessed by comparing their simulations with observations of the atmosphere, ocean, cryosphere and land surface. Unprecedented levels of evaluation have taken place over the last decade in the form of organised multi-model ‘intercomparisons’. Models show significant and increasing skill in representing many important mean climate features, such as the large-scale distributions of atmospheric temperature, precipitation, radiation and wind, and of oceanic temperatures, currents and sea ice cover. Models can also simulate essential aspects of many of the patterns of climate variability observed across a range of time scales. Examples include the advance and retreat of the major monsoon systems, the seasonal shifts of temperatures, storm tracks and rain belts, and the hemispheric-scale seesawing of extratropical surface pressures (the Northern and Southern ‘annular modes’). Some climate models, or closely related variants, have also been tested by using them to predict weather and make seasonal forecasts. These models demonstrate skill in such forecasts, showing they can represent important features of the general circulation across shorter time scales, as well as aspects of seasonal and interannual variability. Models’ ability to represent these and other important climate features increases our confidence that they represent the essential physical processes important for the simulation of future climate change. (Note that the limitations in climate models’ ability to forecast weather beyond a few days do not limit their ability to predict long-term climate changes, as these are very different types of prediction – see FAQ 1.2.)

A third source of confidence comes from the ability of models to reproduce features of past climates and climate changes. Models have been used to simulate ancient climates, such as the warm mid-Holocene of 6,000 years ago or the last glacial maximum of 21,000 years ago (see Chapter 6). They can reproduce many features (allowing for uncertainties in reconstructing past climates) such as the magnitude and broad-scale pattern of oceanic cooling during the last ice age. Models can also simulate many observed aspects of climate change over the instrumental record. One example is that the global temperature trend over the past century (shown in Figure 1) can be modelled with high skill when both human and natural factors that influence climate are included. Models also reproduce other observed changes, such as the faster increase in nighttime than in daytime temperatures, the larger degree of warming in the Arctic and the small, short-term global cooling (and subsequent recovery) which has followed major volcanic eruptions, such as that of Mt. Pinatubo in 1991 (see FAQ 8.1, Figure 1). Model global temperature projections made over the last two decades have also been in overall agreement with subsequent observations over that period (Chapter 1).

faq-8-1-figure-1-l.png


FAQ 8.1, Figure 1. Global mean near-surface temperatures over the 20th century from observations (black) and as obtained from 58 simulations produced by 14 different climate models driven by both natural and human-caused factors that influence climate (yellow). The mean of all these runs is also shown (thick red line). Temperature anomalies are shown relative to the 1901 to 1950 mean. Vertical grey lines indicate the timing of major volcanic eruptions. (Figure adapted from Chapter 9, Figure 9.5. Refer to corresponding caption for further details.)

Nevertheless, models still show significant errors. Although these are generally greater at smaller scales, important large-scale problems also remain. For example, deficiencies remain in the simulation of tropical precipitation, the El Niño- Southern Oscillation and the Madden-Julian Oscillation (an observed variation in tropical winds and rainfall with a time scale of 30 to 90 days). The ultimate source of most such errors is that many important small-scale processes cannot be represented explicitly in models, and so must be included in approximate form as they interact with larger-scale features. This is partly due to limitations in computing power, but also results from limitations in scientific understanding or in the availability of detailed observations of some physical processes. Significant uncertainties, in particular, are associated with the representation of clouds, and in the resulting cloud responses to climate change. Consequently, models continue to display a substantial range of global temperature change in response to specified greenhouse gas forcing (see Chapter 10). Despite such uncertainties, however, models are unanimous in their prediction of substantial climate warming under greenhouse gas increases, and this warming is of a magnitude consistent with independent estimates derived from other sources, such as from observed climate changes and past climate reconstructions.

Since confidence in the changes projected by global models decreases at smaller scales, other techniques, such as the use of regional climate models, or downscaling methods, have been specifically developed for the study of regional- and local-scale climate change (see FAQ 11.1). However, as global models continue to develop, and their resolution continues to improve, they are becoming increasingly useful for investigating important smaller-scale features, such as changes in extreme weather events, and further improvements in regional-scale representation are expected with increased computing power. Models are also becoming more comprehensive in their treatment of the climate system, thus explicitly representing more physical and biophysical processes and interactions considered potentially important for climate change, particularly at longer time scales. Examples are the recent inclusion of plant responses, ocean biological and chemical interactions, and ice sheet dynamics in some global climate models.

In summary, confidence in models comes from their physical basis, and their skill in representing observed climate and past climate changes. Models have proven to be extremely important tools for simulating and understanding climate, and there is considerable confidence that they are able to provide credible quantitative estimates of future climate change, particularly at larger scales. Models continue to have significant limitations, such as in their representation of clouds, which lead to uncertainties in the magnitude and timing, as well as regional details, of predicted climate change. Nevertheless, over several decades of model development, they have consistently provided a robust and unambiguous picture of significant climate warming in response to increasing greenhouse gases.
 

Forum List

Back
Top