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How Well Do Our Climate Models Match Our Observations?
bunratty writes "According to recent articles by Roy Spencer and John Christy, our climate models have done a poor job of predicting warming due to humans burning fossil fuels. They claim that we've observed only a fraction of the warming they predict. But when I look at the source they claim to use, the State of the Climate in 2012, I see that it shows a warming of 0.7 degrees Celsius worldwide since 1980, close to the 0.8 degrees Celsius warming predicted by the climate models. Take a look at the data for yourself. How well do our predictions match our observations?"
It's pretty easy to "predict" temperature trends in years that have already gone by.
That's because you are looking at climate models calibrated against that data that you are comparing to. Circular logic.
If you look at the predictions from past IPCC reports, very few of their predicted temperature profiles match the later observed conditions. That is a failure of the models' predictive power. That doesn't mean there isn't warming, just that the Earth's climate is a more complex system than can be accurately simulated with modern computing hardware.
It's almost as if there aren't big walls in the sky that keep emissions from leaving the countries that produce them.
Spencer has contributed specific work in peer reviewed journals that is part of the scientific discussion, but his overall opinion on climate change is motivated more by his own religion than anything else. He's both sympathetic to intelligent design and signed a statement which said among other things ""Earth and its ecosystems – created by God's intelligent design and infinite power and sustained by His faithful providence – are robust, resilient, self-regulating, and self-correcting." http://en.wikipedia.org/wiki/Roy_Spencer_(scientist)#Climate_change Essentially he believes that climate change isn't happening because his religion won't let him. Note how that statement wasn't even just about climate, but about ecosystems as a whole. Christy doesn't seem to have that same sort of underlying motivation and might make more sense to pay attention to, but in this context, the vast majority of experts disagree with both of them, and when dealing with complicated scientific issues, using expert consensus is a useful heuristic, that's before we get to the serious issue that not only is the expert consensus clear, it is a consensus about some very bad results, not just a consensus about an issue which doesn't have substantial impact.
A more interesting question is why Spencer never publishes any of his alleged massive critiques of AGW in peer reviewed journals. He seems to be quick to a check from the Koch Brothers and various other pro-oil interests, but oddly never seems to actually publish these resounding rebuttals in any kind of scientific venue.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Since it only needs 2C to drop and you get an ice age starting, I fail to see how you can claim 0.7C a minor fluctuation and wonder how it would matter.
That is a perfect example on how to misalign graphs to make them match your agenda. He should be jailed for that.
Apparently the concept of making all weather more extreme has been lost here. That would mean winter storms will be more extreme as well. Perhaps it's hard to imagine why global warming would make more snow in some areas, but failures of some people's imagination doesn't make something less true.
Also, if we're talking about the gravy train, don't the people emitting greenhouse gasses have a much larger financial stake than the scientists researching it? I doubt all the climate research funding world wide was equal to even Exxon's profits last year.
As the old song goes, little things mean a lot. You couldn't see the difference between a little botulin toxin and a lethal dose without a microscope. And I'm sure you wouldn't notice a 0.7 C difference between one room in your house and another, but multiply that amount of energy to a global scale and it starts to add up. Consider what climatologist James Hansen said about the current rate of increase in global warming: “(it's) equivalent to exploding 400,000 Hiroshima atomic bombs per day, 365 days per year. That’s how much extra energy Earth is gaining each day.”
Ask me about my sig!
Where you aware the current drought in California happened after millions of acres of farmland were denied water and the water was released to save a tiny fish in the Delta?
Telecommuting! What about socialization?
Using your comments. We should also cancel out avid atheists too then? I'd be curious to see if there are any REAL people in the middle when it comes to scientists in either way. In same same vein, we should cancel out studies by scientist who get paid to do studies by any person, organization or government that wants to prove global warming is man made. Try to find some real neutrality by honestly curious scientist, I'm wondering if you really could.
Or the fact that we are still coming off of an Ice Age that lasted for more than 100,000 years, and ended less than 10,000 years ago (Or the little Ice Age that ended in 1850). Several models predict that the average temperature at the END of the last Ice Age was 15-20C lower than today.
Is global warming happening? Yes. Is the human race a contributing factor? Probably to some degree. Is the human race the only cause? No.
I can't speak to the accuracy of historic weather data or modern weather models, but I can say this:
Global Warming / Climate Change (pick one, please) alarmists do themselves an incredible amount of damage when they do the following:
1. Grossly exaggerate predictions and base everything on the worst case they can find.
2. Manipulate charts to make changes look far more significant than they really are.
3. Instantly ridicule anyone who disagrees with them on anything, even if that disagreement is valid.
Let's say for the sake of argument that all of the predictions from these weather models are 100% accurate, all of the research and data is correct, and that the climate is indeed warming because of CO2 emissions, and that the climate will warm 5 Celsius degrees in the next 200 years. Let's pretend that the science is completely perfect.
Even if all of that is true, you will find a lot of people who won't even bother listening because they remember crazy predictions like "New York city will be underwater in 20 years!" and "We're all going to be cannibals! Cannibals, I say!"
Do you see why so many people don't listen to those who are trying to push human-caused climate change?
Politics needs to be taken out of the equation. Completely. Everything needs to be 100% transparent. The science needs to be broken down in ways the average person can understand. Even if that happens, it will be decades before the damage the global warming alarmists have caused can be reversed.
Love sees no species.
The difference between the depths of the Little Ice Age and the mid-20th century is only about 1.0C and look at how much of a difference that makes.
Natural forcing actually add up to negative changes in temperatures(though at so small a value they wouldn't even show up on a graph of temperature forcing).
China are experts on big walls, though.
The State of the Climate 2012 paper is... get this... from two years ago. After they had to start "adjusting" their models to reflect reality.
When you look at the actual historical AGW models, we're below their "optimistic" model (the one where we cut CO2 drastically over the last couple of decades - which didn't happen). And a good 0.2 C below their "probable" models.
If you're looking at predictions, go back and look at the climate models from the late 1980s and early 1990s. They're off, by a ridiculous amount.
Out of 90 models (yes, ninety), a grand total of TWO managed to predict the current temperature.
And yet EVERYTHING is now caused by AGW. Heat Waves. Cold Spells, Floods. Droughts. Today, I saw a report linking Crime to Global Warming. Last year, it caused prostitution for impoverished women. About the ONLY thing not linked to AGW is the Heartbreak of Psoriasis and Waxy Yellow Buildup. But hey, it's only February. . . .
Spencer's scientific views are being affected by his religious beliefs. He is a signatory to a document called An Evangelical Declaration on Global Warming, which holds that Earth was created by "God's intelligent design" and that ecosystems are therefore "robust, resilient, self-regulating, and self-correcting". Whatever you might think of this, it is definitely not a scientific statement. Basically, he refuses to accept, for religious reasons, that humans can have an effect on the Earth's climate – in his theology, only God can do that.
Spencer is also a major proponent of the "intelligent design" scam. And both he and John Christy are based out of Alabama, one of the most backward and scientifically illiterate states in the U.S.
No scientist says humans are the only cause. There are other forcings, positive and negative. The very likely (95%-100%) in the IPCC is to the contention that "most" of the rise in temperature is caused by human forcings. Not "all".
I don't think it should be surprising if changes in climate affect the behavior of people in areas. If food becomes more plentiful I bet crime goes down. If food and water become more scarce I bet it goes up. If the weather patterns are changing surely some areas are going to get drier and some are going to get wetter. Also, as events become more extreme all the extreme weather events you sited are likely to happen more often too, don't you think? So you're right, global warming almost certainly is doing all those things.
I don't see why it's controversial to think that. Even if you don't think people have anything to do with changing climate all those effects are obvious outcomes of it changing, and I don't think many people actually doubt that it is changing.
For several years Gavin Schmidt, one of the principals of the NASA/GISS Model/E climate model, has been doing a comparison of model output to observations. There isn't an update for 2013 yet but the comparison through 2012 is available here.
Where does the 0.7C warming since 1980 figure come from exactly? I make it roughly 0.7F (note: FAHRENHEIT) from 1980 until the last point in 2012. That's an anomaly of around 0.4C, which seems to tie in with the graph on the R Spencer page.
Look back before that, the period from 1950-1974 (approximately). How well do the models match there?
Cherry picking is bad science. You have to look at the whole record from the start of the Industrial Age... and the models haven't been particularly good.
That's not an anti anthropogenic global warming statement, by the way. It's a "science is hard and you can't understand a subject after ten minutes of reading" statement.
#DeleteChrome
And yet, tree ring data from California shows that region has been in drought for something like 1600 out of the last 2000 years.
Much of it significantly *before* modern technology and CO2 pollution.
Could it be the real problem is that we don't actually know what the average temperature was before 1700?
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
While there is non human fluctuation in CO2, currently humans put out for 32 Gigatonnes of CO2 per year. Far exceeding the amount can go through the carbon cycle in a year.
CO2 traps IR.
Clearly, the current rising trend is due to humans.
Without the excess CO2 we have been emiting, we would not be experiencing the current temperature rise.
The Kruger Dunning explains most post on
Or the fact that we are still coming off of an Ice Age that lasted for more than 100,000 years, and ended less than 10,000 years ago (Or the little Ice Age that ended in 1850). Several models predict that the average temperature at the END of the last Ice Age was 15-20C lower than today.
So over 10k years temperature raised 20C, that is (20 / 10000) * 10 = 0.02C per decade, very far from 0.7 / 3 = 0.23 per decade that we see now.
I don't have sources from your numbers, and it's probably safe to assume that the rate of temperature change isn't constant either... So maybe we shouldn't try to model this at all, my calculations above are certainly as ignorant and non-sense as your postulation of numbers...
Is global warming happening? Yes. Is the human race a contributing factor? Probably to some degree. Is the human race the only cause? No.
True, there are many factors that affect the environment, but non other does it with the same speed as humans.
Global warning is primarily man-made, it's a real problem, that's the scientific consensus. And I'm fairly sure that most people on slashdot as just as qualified to discuss the scientific consensus around global warming, as soccer moms are qualified to discuss the merits and "dangers" of vaccinations.
Or the fact that we are still coming off of an Ice Age that lasted for more than 100,000 years, and ended less than 10,000 years ago (Or the little Ice Age that ended in 1850). Several models predict that the average temperature at the END of the last Ice Age was 15-20C lower than today.
Is global warming happening? Yes. Is the human race a contributing factor? Probably to some degree. Is the human race the only cause? No.
I like this game.
.002C/year. .7C over 30 years is .023C/year
Do humans have the capability to mitigate their contribution to warming? Yes. Does any other warming phenomenon? No
Do humans care if these warming effects drastically disrupt the climate that our current society has adapted to so well? Yes. Does anything else? No.
Also a quick note, 20C over 10000 years is
Just so you know: That "97 percent of all scientists in the world" silliness came from a rigged "poll."
Basically, an AGW-supporting scientist polled a number of his AGW-supporting scientist friends and co-workers - 30 or so - and asked them if they thought AGW was real.
That's where your number came from. Which should tell you something about the actual support for AGW among the scientific population at large...
They recently came up with another poll, where they cherry-picked a bunch of papers, and said "97% of scientific papers agree!" While not mentioning that only about a third of them actually addressed AGW, and they got their "new" 97% by only looking at 65 papers. Out of 12,000. Oops.
ok, so.. read through all of this page, and repeat that this is just a guy polling his friends:
http://climate.nasa.gov/scient...
I, too, used to think climategate showed all those things. I read article after article about them and how it's all over for AGW, etc. However, when taken in context, those emails actually refer to something totally other than what they were made out to refer to. I highly recommend you check out this video and this one wherein potholer54 takes an in-depth and impartial look into climategate and reveals what it actually shows... as a spoiler, it doesn't reveal that there's a giant AGW conspiracy amongst all the climate scientists in the world.
This all came out in the Climategate emails. But you never heard about those, did you?
We are well aware of release of emails from the University of East Anglia. The attempt at connecting it with watergate fails, as unlike watergate there is no smoking gun. Nothing in the emails shows any conspiracy. There is no blocking of "anti-AGW" papers. There are no "anti-AGW" papers to block. And nothing in the emails says otherwise
"Hide the decline" ring a bell?
It sure does.
"Many commentators quoted one email in which Phil Jones said he had used "Mike's Nature trick" in a 1999 graph for the World Meteorological Organization "to hide the decline" in proxy temperatures derived from tree ring analyses when measured temperatures were actually rising. This 'decline' referred to the well-discussed tree ring divergence problem, but these two phrases were taken out of context by climate change sceptics, including US Senator Jim Inhofe and former Governor of Alaska Sarah Palin, as though they referred to some decline in measured global temperatures, even though they were written when temperatures were at a record high.[32] John Tierney, writing in the New York Times in November 2009, said that the claims by sceptics of "hoax" or "fraud" were incorrect, but that the graph on the cover of a report for policy makers and journalists did not show these non-experts where proxy measurements changed to measured temperatures.[33] The final analyses from various subsequent inquiries concluded that in this context 'trick' was normal scientific or mathematical jargon for a neat way of handling data, in this case a statistical method used to bring two or more different kinds of data sets together in a legitimate fashion.[34][35] The EPA notes that in fact, the evidence shows that the research community was fully aware of these issues and that no one was hiding or concealing them.[36]"
http://en.wikipedia.org/wiki/H...
You have nothing.
Also a quick note, 20C over 10000 years is .002C/year. .7C over 30 years is .023C/year
Also worth noting is that the global temperatures didn't change 20C. The last glacial maximum was only 3C to 5C cooler than the present (http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6s6-es.html). The height of the current interglacial period occurred about 8000 years ago. Since then temperatures have been dropping (up until recently).
The temperature difference (on a global scale) between the last ice age and the current interglacial was 4-7C, not your 15-20C.
The human race is not the only source of climate forcings but lately the effects of the known natural forcings would point to a slight cooling trend but it's been warming so it's probably fair to say humans are responsible for more than 100% of the warming.
A warm spell somewhere is evidence for AGW, but a cold spell across a region should be ignored.
Well, there are (to broadly generalize) four positions on AGW:
1) Scientifically informed acceptance.
2) Fervent, incorrect denial.
3) Fervent, incorrect acceptance. ("OMG! Hurricane Katrina was directly caused by Global Warming!")
4) Easily swayed people with the memories of goldfish.
#4 is the group of people that keeps "swing voting" on it depending on the current weather.
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
The Hiroshima fireball was 370 metres (1,200 ft) in diameter, with a surface temperature of 6,000 C.
The surface area of the Earth is 510 million square kilometers.
It seems to me that 400,000 of these could raise the surface temperature of the earth quite a bit. That's 24,000,000,000 square meters of the surface experiencing a 1 degree temperature raise. 40,000 square kilometers experiencing some 300 meter high heat wave of 1 degree too hot per day. In 13 days, the entire earth's surface has raised by 1 degree. When you account for the oceans, the land, and convection mixing this in, you're talking more like 300 times as much energy needed to get a 1 degree raise--a year to raise the temperature 1 degree, including the temperature of the oceans and upper atmosphere. With no escape to space; this is gain.
My god. By 2012 the average summer temperature in Baltimore would be 155F.
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"Basically, an AGW-supporting scientist polled a number of his AGW-supporting scientist friends and co-workers - 30 or so - and asked them if they thought AGW was real."
Not quite true. The original "huge consensus" rumor was started by an article (NOT a peer-reviewed paper) that appeared in Nature by one Naomi Oreskes, years ago. Oreskes claimed to have surveyed a database of science papers and concluded that none of them (not one) disagreed with the greenhouse gas global warming idea.
It was soon shown that Oreskes' "study" was in fact a textbook example of cherry-picking. She had searched the database for papers that included the phrase "global climate change". Only those were included in her analysis. The problem with that being that at the time, only papers that were ABOUT the effects of greenhouse gas warming mentioned the phrase "global climate change" at all. So, in effect, she selected out of the scientific literate just the papers about greenhouse global warming, and then conclude that they all agreed about greenhouse global warming! How surprising!
The fact was, of course, that the majority of climate papers were not about greenhouse warming and never mentioned the subject at all. But those weren't counted.
This "consensus" idea was bolstered by people claiming that almost all of the "thousands" of scientists behind the latest IPCC report had agreed about it. This, too, was a distortion of the truth. The scientists involved in the AR report at the time numbered in the hundreds. There were about 2,500 or so reviewers, and not all of those were scientists. Further, not all of them actually agreed.
Shortly after that, the Petition Project was undertaken to show that scientists in fact did not agree. Some 30,000 people with actual science or engineering credentials signed the petition DISagreeing with greenhouse global warming, and their names and professions are still publicly available at petitionproject.org. More than 9,000 of those were PhDs... far more than the 2500 who supposedly agreed, again many of whom had no advanced degrees.
Another "study" was done in this last year, which came up with that "97%" figure. Unfortunately, THAT "study" suffered from exactly the same flaw as the discredited Oreskes study: it searched the literature for papers that contained the phrase "global climate change". Self-selection at its finest.
And of course then there's the real kicker here: even if these "studies" had not been statistical nonsense, the fact remains that "consensus" is not science. If consensus were a scientifically valid measure of anything, we'd still be in the stone ages.
From the article;
Since 1976, every year including 2012 has had an annual temperature above the long-term average. Including the 2012 temperature, the rate of warming is 0.06C (0.11F) per decade since 1880 and a more rapid 0.16C (0.28F) per decade since 1970, according to the 2012 annual report from NOAA's National Climatic Data Center.
Take look at the graph they are referring to. Between 1880 and 2010 there is a change of 1.43 F giving a per decade increase of .11F. But wait, that is not the whole picture. It ignores the period between 1880 and 1910 when global temperatures were decreasing. If you look at the increase since 1910 you get 2F over ten decades which is .2F per decade. It also ignores the time between 1910 and 1940 where the temperature changed 1.1F or 0.37F/decade. Compared with the time between 1910 and 1940 global warming is slowing.
To me it looks like they are picking data that agrees with their conclusion.
Or "The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't. The CERES data published in the August BAMS 09 supplement on ... shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate."
Heh, I love it when deniers mindlessly repeat that quote. You don't even know what it means, do you? Because if you did, you certainly wouldn't be mentioning it.
You see, we measure how much energy the Sun outputs. And we measure how much the Earth reflects of that energy (its albedo). We also measure how much it radiates, which - if the Earth was at a stable temperature - would be the same as the difference between the first two. Understand so far? That's what the "CERES data" refers to.
What Trenberth is saying is that the CERES data shows there should be far *more* warming than we're actually measuring! When you take into account air temperature increase, melting ice, sea temperature increase, etc etc it *still* leaves a big chunk of energy to account for. Now, any sane person would therefore assume that the energy can't just vanish: it's got to go somewhere that we aren't measuring.
Not the deniers, they think it's all being whisked away by the natural cycle fairies. Or perhaps they just don't understand what it is they're saying and are mindlessly repeating what they read on some blog. Hey, maybe you can tell us. Which is it?
Igor Presnyakov stole my hat
My god. By 2012 the average summer temperature in Baltimore would be 155F.
Ah don't worry, we already hit 250C here this past summer. Pretty sure I saw car tires melting in the parking lots...and people bursting into flames. But we've fixed that problem, with this glorious Canadian invention called..."winter."
Om, nomnomnom...
On a global scale, indeed: 0.7C is a small variation. The Earth has had larger variations before, and this is not unusual on a geological scale (although to be fair, its happening at a faster time scale than most of the climate changes in the past.)
However, 0.7C pretty much validates the models. If the anthropogenic greenhouse effect is not real, you need three things:
(1) You need to find an explain an explanation for why the radiative forcing does not increase temperature
(2) You need to find a hitherto-unknown effect that is causing the warming that we measure, and
(3) You need to find an explanation for why the amplifier that amplifies effect (2) to be large enough to increase the temperature doesn't also amplify the greenhouse effect. (and, contrawise, you need to explain why whatever effect it is that cancels out the greenhouse effect, (1), does not also cancel out effect (2).)
While 0.7C may be small, you should also note that we are continuing to put carbon dioxide into the atmosphere.
http://www.geoffreylandis.com
Your clarification that the climate scientists were trying to hide the decline of the tree ring data as opposed to hiding the decline of the temperatures isn't very reassuring. If they've used tree rings to reconstruct worldwide climate temperatures as a proxy, and this proxy diverges from observations to the point that they have to "hide the decline", I think there's a definite problem with their science. Doesn't this invalidate the entire climate/temperature reconstruction that includes these tree rings? Why would they have to use a statistical method or 'trick' to make the data fit the theory? That doesn't sound like something a scientist interested in discovering the truth should have to do. Unfortunately, this isn't about pure science, as there is plenty of money and politics involved on both sides of the argument. There are reputations, careers, and honor at stake too. The email leaks revealed the science isn't as clear cut as they would have us believe. They also revealed that there are some climate scientists who are quite unwilling to even consider any evidence that contradicts their own beliefs. It's especially concerning when they advocate hiding or even deleting info, data and communications in order to avoid having to respond to FOI requests. Why would they need to do this?
And even most of the data more than a few decades back is pretty suspect.
I won't join Slashcott. OTOH, If Beta goes live, I just won't be back until it's fixed. Sorry Dice.
"Let's pretend"... Yes, the AGW crowd seems to be doing plenty of that with their numbers.
Take down all those rural weather stations because we don't need them. We can just use the numbers from the ones located in the middle of the asphalt parking lots and pretend we know how to properly adjust the numbers to get some data we can pretend is accurate.
And yet, tree ring data from California shows that region has been in drought for something like 1600 out of the last 2000 years.
Much of it significantly *before* modern technology and CO2 pollution.
Could it be the real problem is that we don't actually know what the average temperature was before 1700?
No, that isn't the case. There are many different ways in determining temperature. Tree ring data is one, but there are ways of figuring out temperature far past the time trees are capable of...
Sea levels are set to rise by a meter or more by the end of the century, and the frequency of both droughts and strong storms has already increased dramatically. No, these are not good things.
Also, we only need about 2.2C of warming or so for all of Greenland to melt (though it will take a few centuries to do so). Greenland melting means sea level rise of about seven meters. That's going to drown a lot of cities.
The phrase "global climate change" does not specify whether the paper is supporting or disagreeing with the consensus view. It's a neutral phrase. It's just a way of limiting the papers to only those that are on-topic. Why do you think limiting to only on-topic papers was a bad thing?
I can guarantee you that there is no possible selection criteria that would result in a significant number of peer-reviewed papers that claim that global warming isn't happening, that humans aren't causing it, or that global warming isn't quite dangerous. I'm sure you can find some, but they won't come anywhere close to the number that support global warming.
this article was published in 2009 From the abstract:
"Here, we use an extensive dataset of 1,372 climate researchers and their publication and citation data to show that (i) 97–98% of the climate researchers most actively publishing in the field support the tenets of ACC outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers"
This study does not seem to have the flaws you mention. There have been several studies I've seen with similar outcomes.
Millions long for immortality who do not know what to do with themselves on a rainy Sunday afternoon. -- Susan Ertz
Oh no. The government of the United States, how untrustworthy compared to an anonymous stranger on the internet.
With the US government's track record for truthfulness and "transparency", particularly over the last 20 years, I'd be far more inclined to trust Joe Isuzu over the US the government.
http://youtu.be/nJMq_7alQpU
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
However, he pretends that the problem with "hide the decline" is about something other than tree rings...
Where does he say that? He says at 4:12: "But in fact, Jones was talking about something completely different [than the decline in the global temperature]: the apparent decline in temperatures shown by tree ring data since the 1950s." He is exactly stating that "hide the decline" has something to do with tree rings.
Basically, the guys "hiding the decline" desperately needed to hide the decline in temperatures for that part of their reconstruction in order for that reconstruction to be used as a metric for past temperatures versus CO2.
Yes, exactly as potholer says at 4:27: "The argument is whether tree rings should be used when reconstructing pre-industrial climates." You make this out to be something sneaky and hidden from public, especially combined with your closing statement:
The thing you also missed about the Climategate problem for AGW fans: a lot of what they said would be fine, in a publication, or in an answer to a paper. It was, however, stuff they never told anyone, because it poked huge holes in the foundation of their work.
However, at least in this case, you are simply wrong. It's been openly discussed since at least 1998 when a paper called "Trees tell of past climates: but are they speaking less clearly today?" was published. A quote from the paper: "This is illustrated in figure 6, which shows that decadal trends in both large-scale-average [Tree-Ring Width] and [MaXimum latewood Density] increasingly diverge from the course of decadal temperature variation after about 1950 or 1960." The lead author, Keith Briffa, even works at the CRU! Clearly this was openly talked about, and before the "hide the decline" email (which was in 1999).
What else ya got?
Uh, no....
At most sea level rise is 2-3mm/year, for the next 86 years gives about a quarter of a meter.
The current sea level has been rising for hundreds of years and shows no acceleration.
See http://sealevel.colorado.edu/
All these scare scenarios are based on the same dubious models.
Real data, no problem.
The thing is, it really doesn't matter how many scientists support it. Science isn't a democracy. See the pamphlet called 100 authors against Einstein. Einstein replied that it didn't need 100 people do disprove his theory of relativity, rather all it needed was one fact. I really hate how modern science has turned into this "if the majority believes it, it must be true." I'm sure the majority of the world still believes in creationism, but they're also still wrong.
(By the way, who decides what makes you a scientist anyways?)
Careful with names containing L slashdot.org/~AiphaWolf_HK slashdot.org/~AlphaWoif_HK slashdot.org/~AiphaWoif_HK
Not quite true. The original "huge consensus" rumor was started by an article (NOT a peer-reviewed paper) that appeared in Nature by one Naomi Oreskes, years ago. Oreskes claimed to have surveyed a database of science papers and concluded that none of them (not one) disagreed with the greenhouse gas global warming idea.
Ahh, yes, the old Oreskes essay "scandal". It was not published in Nature, but in Science. Small quibble, but if you're going to be critical of something, at least get your facts correct.
It was soon shown that Oreskes' "study" was in fact a textbook example of cherry-picking. She had searched the database for papers that included the phrase "global climate change". Only those were included in her analysis. The problem with that being that at the time, only papers that were ABOUT the effects of greenhouse gas warming mentioned the phrase "global climate change" at all. So, in effect, she selected out of the scientific literate just the papers about greenhouse global warming, and then conclude that they all agreed about greenhouse global warming! How surprising!
No, it wasn't. It was exactly what it claimed to be. The phrase used did not include the word "global"; it was just "climate change" (which could go either way -- remember all those supposed "global cooling" papers from the 70s? They would still qualify as they referred to "climate change").
Yes, she chose "climate change" because, you know, all those papers on the reproduction cycles of ring-tailed lemurs are not so relevant to the subject.
She did not select papers about greenhouse global warming, as those were not her search terms. The fact that most of the papers that mentioned "climate change" endorsed anthropogenic causes to some degree or another, rather than saying it was something else when they most certainly could, is significant and not a simple result of cherry-picking.
The fact was, of course, that the majority of climate papers were not about greenhouse warming and never mentioned the subject at all. But those weren't counted
Incorrect. 25% of the papers she counted did not endorse or were neutral on the subject of anthropogenic causes. NONE of them rejected it.
Further, her essay was formally challenged by Dr. Benny Peiser, who ended up later retracting his challenge, concluding:
"Only [a] few abstracts explicitly reject or doubt the AGW (anthropogenic global warming) consensus which is why I have publicly withdrawn this point of my critique. [snip] I do not think anyone is questioning that we are in a period of global warming. Neither do I doubt that the overwhelming majority of climatologists is agreed that the current warming period is mostly due to human impact."
This "consensus" idea was bolstered by people claiming that almost all of the "thousands" of scientists behind the latest IPCC report had agreed about it. This, too, was a distortion of the truth. The scientists involved in the AR report at the time numbered in the hundreds. There were about 2,500 or so reviewers, and not all of those were scientists. Further, not all of them actually agreed.
"bolstered by people" By whom? The 97% figures come from several independent studies, most of them dealing with longer periods and an order of magnitude larger sample size than the one Oreskes used. None of them refer to the "thousands of scientists behind the latest IPCC report". I question where you're getting your information, because it isn't from the people performing the actual research.
Shortly after that, the Petition Project was undertaken to show that scientists in fact did not agree. Some 30,000 people with actual science or engineering credentials signed the petition DISagreeing with greenhouse global warming, and their names and professions are still publicly available at petitionproject.org. More than 9,000 of those were PhDs... far more than the 2500 who supposedly
-SS "Teach the ignorant, care for the dumb, and punish the stupid."
Over 10,000 scientists were invited to participate. That a whole lot of 'friends and coworkers'
A Good Troll is better than a Bad Human.
Bullshit. If there is good data that is contrary to the general consensus, you better believe that scientists will claw for it....
A Good Troll is better than a Bad Human.
The IPCC's attribution graph shows the various natural and man made radiative forcing's. Without mankind's influence, most climate models predict a very slight cooling for the 20th century. Feedbacks are far more difficult to quantify however using archaeological evidence their magnitude can be inferred. Climatologists use this information to calculate a metric called climate sensitivity, this number has hardly changed since it was first derived in the 1970's. A lot of people think the IPCC is exaggerating, observation has shown that their predictions are on the conservative side (in particular the rate of melt at the north pole), cautious conservatism is what one would expect when a couple of thousand experts agree with each other.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
1) easy, CO2 is a pretty shitty greenhouse gas water is much more important.
Water is indeed a very good greenhouse gas. It also condenses out of the atmosphere, in the form of rain. Carbon dioxide does not. As a result, the amount of carbon dioxide in the atmosphere has a long-term effect. The amount of water vapor in the atmosphere, on the other hand, goes in and out of the atmosphere on a short time scale, driven primarily by the temperature-- warmer air holds more water than cold air.
The infrared absorption of carbon dioxide is measured, by the way. It's not something made up.
2) we've been coming out of an ice age for 10,000 years,
Correct-- or, more correct, we are out of the ice age.
that this remains unexplained
Fifty years ago it was unexplained. It's pretty well understood now.
leaves any "blame the humans" nonsense as laughable.
The fact that there causes of climate variation other than human input does not imply that human input doesn't also have an effect. As was pointed out, the effect is small, about 0.7C so far. But it is real.
3) no, you dont, see one and 2
The theory matches the data. If you have another theory, you have to both explain why the theory based on actual measured facts, like the absortion of infrared by carbon dioxide, isn't true, and you also have to explain why we see rising temperature anyway
like the sea rising... panicing about a few mm when in many places it changes on a meter scale every day.
Huh? I'm not panicking. I do, however, believe that it is important to not dismiss the science because you don't like the conclusions.
4) Warming is much better than cooling.
I agree. That is, however, no reason to dismiss the science.
http://www.geoffreylandis.com
If you want to assert the anthropogenic greenhouse effect is both real, and dangerous, the burden of proof is on the affirmative to come up with a necessary and sufficient falsifiable hypothesis statement which rules out natural climate change as the reason for observed temperatures.
OK. My prediction is that if you aim an infrared spectrometer at the sky, you will see downwelling infrared radiation from the CO2 spectrum.
This prediction is falsified if you don't see downwelling infrared radiation.
Hey, we see it! I win. Carbon dioxide actually does re-radiate absorbed thermal infrared. The greenhouse effect is real.
This was done over a century ago, by the way. The greenhouse effect has been known for a long time. Good thing, too; the Earth would be frozen if it didn't exist.
http://www.geoffreylandis.com
If consensus were a scientifically valid measure of anything, we'd still be in the stone ages.
Perhaps that's why you have so much trouble comprehending this issue, go and read about Karl Popper's "republic of science" and tell us all how that is different from "consensus". At the end of the day Science is a philosophy, your own track record of posts on AGW indicate you are unable to apply that philosophy to real world questions. You clearly judge your sources not by their content but by their political colour, which is why you link to Anthony Watts and avoid the internationally recognised leaders in the field such as Mann or Hansen.
This post is no different, first you say a valid survey means nothing, then you say it's wrong, then you say another survey, the Petition Project, proves the opposite. Think about it like Karl Popper would, why do accept the politically inspired survey at face value but reject several other much more rigorous surveys that clearly show the opposite conclusion. If that's not enough to convince you that you are being used as a useful idiot then just look at the tortured logic of your post, all to try and prove black really is white.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Actually, most scientists in the climate field believe in AGW. They will continue to do so as long as it is easier to get funding for projects intended to prove it exists. They will cease doing so when it's easier to get funding for projects intended to prove it doesn't exist.
What an opportunity for the fossil fuel companies! If they got together they could easily provide a $1 billion fund to provide grants to prove AGW doesn't exist. They ought to try it and see who bites.
The reality is that any scientist who tries to get grants based on false premises sooner or later will find themselves shut out from the process. That's the beauty of science, it's self correcting. It may take a while but eventually reality wins out. With a few notable exceptions scientists are smart enough to know this and avoid promulgating science the know is wrong.
You actually wouldn't see anything, as the spectrum of water swamps most of the IR spectrum. Hydrogen bonding is funny.
Yes, in some wavelength bands all you see is the water. In others the CO2 dominates. (It also somewhat depends on whether you're lookig up from sea level in the tropics, or from temperate zones).
But, overall, if you take the spectrum (especially across the CO2 band at around 15 microns), yes, you can clearly see the downwelling IR from CO2 emission.
I could show a dozen plots for you, but here's a nice one with the big CO2 emission labelled:
http://klimakatastrophe.files....
http://www.geoffreylandis.com
The lifetime of water emitted into the air is so short that no, you really don't get a long-lasting greenhouse effect by directly emitting water. It condenses out. We call this "rain" on our planet.
It is, however, an amplifying effect: if you make the average temperature a little bit warmer for some other reason, that means that more water evaporates and the atmosphere can hold more water, which raises the temperature. This increases the effect of other greenhouse gasses, such as CO2.
If you ever get to the point where the amplification factor is greater than 1 (that is, 1 increase in temperature increases the atmospheric water such that it increases the temperature by another 1), you get "runaway greenhouse effect." Fortunately, Earth is far away from this condition. (It is believed to have happened on Venus, though.)
http://www.geoffreylandis.com
->The infrared absorption of carbon dioxide is measured
its absorbtion and radiation
but more CO2 definately doesn't mean a hotter atmosphere.
Because you don't just trap more heat - you also prevent more sunlight entering in the first place.
No. Take a look at the solar spectrum some time. Almost all of the energy of incident sunlight is in a spectrum range in the visible and near IR-- peaking around one micron. The energy of the exiting infrared is in much longer infrared-- ten to twenty microns. (The fact that it's longer wavelength is Wien's law). You can have an atmosphere transparent to incident light, but absorbing to exiting infrared. This was discovered in the late 1700s.
Venus isn't hot because of the greenhouse effect, it's hot because of the enormous pressures caused by an incredibly dense atmosphere.
I'm sorry, but at this point you are revealing that you don't actually understand what you're talking about, so bye, have a nice life.
http://www.geoffreylandis.com
You really think the temperature of venus is from the greenhouse effect?
Yes. In fact, because the atmosphere of Venus is so opaque in the thermal infrared, it is easy to analyze-- it's one of the few planets that can be analyzed with a relatively simple back-of-the-envelope calculation.
That's funny.
If you don't understand that the temperature of surface of Venus is due to the greenhouse effect, you don't understand the greenhouse effect. It's not actually a crime to not understand something-- the greenhouse effect is poorly explained in popular culture, and few people have even a clue how to do a calculation, even a simple one-- but when you don't understand something, that might suggest that you should learn, rather than shoot off uneducated opinions.
http://www.geoffreylandis.com
The current sea level has been rising for hundreds of years and shows no acceleration. See http://sealevel.colorado.edu/
No. As your link points out, sea level has been rising at 3mm/year since 1991. Earlier in the century it was rising at a much lower rate. Prior to that (for the last 4000 years) it was not rising at all: http://upload.wikimedia.org/wi....
Geoff,
You don't seem to get it, the CAGW crowd including yourself want huge sums of money taken from people to do something (like fuck the energy sector) and keep coal plants from being built by denying financing through the world bank (already happening) so poor countries are taking it in the ass economically.
No, actually, I don't.
I want people to understand the science. I want people to understand that there is science here; that the greenhouse effect has been known and studied for a long time, it is relatively well understood, and the models are well tested. I want people to stop attacking the science when they don't like the political consequences that they believe would ensue if they believed it. The argument "it would be extremely expensive if the science were correct so therefore the science must be wrong" is not a logical argument. This is worth emphasizing: the correctness of the science is independent of your beliefs about the consequences.
As for the question "what should we do about it-- well, that is worth discussing. Maybe nothing. But, as far as I can tell, whenever anybody suggests any discussion, a small group of people start shouting "Stop discussing this! The science is a hoax! It's not real! It's a scam!"
... One last thing, just what ppm level of CO2 would be optimum for you?
Me personally? I live in Ohio-- a bit of global warming would be nice, I'm in favor of it. Global warming will both have benefits and cause problems, of course. I find it amusing to notice that the three countries that have been most adamant in blocking global warming discussions are Canada, Russia, and Norway-- obviously, they've done the same calculation.)
http://www.geoffreylandis.com