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Yeah it's not even close to 10%. There was a claim by Times Atlas cartographers back in 2010 that Greenland had lost 15% of its ice by area, not volume, but ice specialists jumped on that, and it was eventually retracted.

I'm not aware of reliable figures for total ice loss in the last century, but even current ice loss rates would mean an upper bound of about 1%.

I'm familiar with John Christy and was aware of his testimony before the House Science, Space & Technology committee. I skimmed through the PDF and didn't find anything that surprised me. I don't hold Christy in very high regard based on past performance.

Here is a critique of the graphs Christy used by Gavin Schmidt. Schmidt basically said Christy's graph were inconsistent, misleading and slanted toward making the difference between models and satellite observations appear greater than they actually are.

I will also note that in 2016 after Christy's testimony that both major satellite records, UAH and RSS set new all time records for high temperatures reducing the discrepancy between models and satellite observations.

Also, it should be noted that the real world forcing turned out to be less than that used in the models which caused a warm bias in the model output. Quoting Gavin Schmidt:

In work we did on the surface temperatures in CMIP5 and the real world, it became apparent that the forcings used in the models, particularly the solar and volcanic trends after 2000, imparted a warm bias in the models (up to 0.1C or so in the ensemble by 2012), which combined with the specific sequence of ENSO variability, explained most of the model-obs discrepancy in GMST.

Rerunning the models with the actual forcings that occurred rather than the expected forcings that were fed into them ahead of time reduces the model-observation discrepancy by quite a bit.

One other thing, Christy's graph of satellite observations and radiosonde (balloon) observations only go to 2005 but since about 2000 there has been considerable divergence between satellite observations and radiosonde observations. This appears to be because of uncorrected for drift in the satellites orbit. Why didn't Christy plot the radiosonde data up to say 2014? My answer would be because it undermines his argument about tropospheric temperature trends.
 

Dr. Christy certainly paints an alarming picture. It's a shame that he and Dr. Spencer are alone in their opinions. But I am sure that is the result of a vast conspiracy and not the quality of their ideas. So to repeat for both of your sakes, whether or not the GCMs are accurate is not an argument for or against AGW, any more than a potentially-flawed epidemiological model would invalidate the germ theory of disease. As it happens, Dr Christy's results are potentially interesting, but his presentation is fairly biased. I don't begrudge him that, I think. And if he or Dr. Spencer can come up with a plausible negative feedback mechanism then I am sure they would be taken quite seriously. The scientific consensus has reversed itself on this issue before, remember. The situation is analogous to the debate about dark matter. Yes, if you only look at galactic rotation curves, there is room for an alternate theory (MOND), and there have been a number of published papers. No presentations to Congress about the issue though, because it's not been made into a political issue. Multiple other lines of evidence however point to a different explanation. It's not completely impossible for some new observation to reverse the balance of evidence, but it hasn't happened yet, and the observations that would be required are about as unlikely as it is possible to get. Dr. Christy has already been a lead author on sections of the IPCC's assessments, it's not like people are ignoring his ideas or not incorporating them into the body of scientific literature. The issue is that his argument is flawed. Now, if you have nothing better to offer than Spencer and Christy I do believe we are done here. However, I would still encourage you to review the early history of AGW, as being fruitful for counterarguments. I would certainly like to see it disproven, and there were specific observations that have taken the theory from discredit to the consensus position. If your worldview can handle new information, you could potentially find additional reasons to sustain those objections. The argument you're presenting is crap, and everyone knows it. Find a better one.

That's part of how we arrive at a consensus. People propose a hypothesis and suggest likely consequences. If the predicted observations come to pass (as is the case with IPCC AR4 projections accurately predicting the observed global atmospheric temperature increase over the last 16 years) then we have more confidence in that idea. If they do not then we need to understand why not.

The data for reproducing climate model predictions and published research already should be fully released, and as a practical matter, archived. Here is a set of links:

http://www.realclimate.org/ind...

So what is this other data that they are trying to rescue from Trump?

If there is data missing, then that should be published. The climate research community might also want to update their computational tools from the dusty Fortran decks to something more modern. Everybody should be able to reproduce climate models on a modern desktop computer with a GPU and check for themselves.

How much will sea level rise by 2100? Nobody really knows.

Here is the range of predictions, including error bars, from the IPCC.

We can make reasonably good guesses, but knowing whether it's going to be half a meter or a meter, to give two possibilities) would be very useful in deciding what to do about it.

In what way does a foot more or less make much of a difference? A third of the Netherlands lies below sea level; those kinds of modest changes just aren't a big deal for a wealthy nation like ours.

And why would, say, $5 billion / year not be enough to figure that out, instead of the $9 billion we are spending? And maybe we are spending even more.

Budgets and spending need to be justified, and because we don't have unlimited amounts of money, we need to make tradeoffs. It's the job of the Trump administration to figure out where the money is spent right now, whether it is spent wisely, and what tradeoffs to make. If you can make a dollars and cents argument for current spending levels, make it. Waving your hands and saying "it would be very useful" isn't a rational argument about the federal budget.

Personally, I think the rational thing to do is to shift most of that climate change money to research in nuclear and fusion energy, material science, new transportation technologies, and cancer research. Those things are much more "Important to know" than expensive guesses about whether sea levels will have risen by 2 ft or 3ft half a century after I'm dead.

To (1), see this and this and this and the obligatory xkcd. Important take home message - it's not just the raw scale of increase, but the rate of increase. It's well outside of a natural timescale which those same historical records indicate is on the order of thousands of years. What's happening now is 8x faster. Also, we know what natural causes drive global temperatures (Milankovitch cycles, ninos, volcanic eruptions, and other things) and can model that. When we take those into account, the observed warming is NOT recovered. Only including the effects of increased CO2 and CH4 levels accounts for the observations.

To (2), see this, and this and a lot of other refs if you google it. Main take home point: in the past, natural global warming (which should take place over thousands of years, see above links), has lead to the further emission of CO2 coming out of the oceans and other places (see here, hence the lag. This was predicted to be the case by Hansen et al before the lag was discovered.

Here's the full article: http://www.realclimate.org/ind...

CMIP3 was used in AR4. CMIP5 was used in AR5.

Here's how actual temps compare to the CMIP3 model output used in the IPCC AR4:

What caused the several centuries long mega-droughts in California in the last 2000 years before Manmade Climate Change?

Previous California mega droughts coincided roughly with the medieval warm period and "caused the collapse of that continent's most advanced pre-Inca empire, the rich and powerful state of Tiwanaku". That warming coincides with a period of higher than average solar radiation and less volcanic activity - both natural factors that would cause warming. Man made global warming has driven modern temperatures well above the relatively high temperatures observed at that time - in spite of the fact the sun is now at its dimmest in a half century. If the droughts are in fact related to global temperatures then California ought to look at making some drastic changes to their water management. It's only going to get hotter from here.

Before flaming or marking me a troll or something, look it up. Google "roman grapes england". Know when you're being lied to by a bunch of people that want to take your money.

Very sage advise. You could even just Google "grapes England" and find that grapes are still grown in England. But then your last sentence there would seem a tad ironic.

Regarding our bet, things aren't looking so good for you: http://www.realclimate.org/ind...

global warming is actually beneficial for the first couple of degrees for humanity as a whole, according to the IPCC even (AR5)

That finding relies on a paper by Richard Tol called “The Economic Effects of Climate Change”. It found that any benefits are sunk after 1C warming. Since we've already warmed by 1C, any further warming will have detrimental effects. The impact is non-linear so things do go down hill quite fast after the next 1C. This was an aggregate of previous studies. Unfortunately "Gremlins intervened" and among other issues, minus signs were dropped from two of the impact studies. The corrected paper is quite a bit less optimistic.

The CO2 based models are still getting it hopelessly wrong.

CMIP3 from the IPCC AR4 is pretty much bang on.

Dude Methane feedback is so 2000, even the RealClimate.org echo-chamber debunks your position. Do try to keep up.

Dude Methane feedback is so 2000, even the RealClimate.org echo-chamber debunks your position. Do try to keep up.

And once we manage to get down to decades AC like him will ask for year by year resolution, as if this had an impact on a trend analyzed over thousands of years.

At any rate you can get better resolution by combing many different sources, and run various statistical techniques to the the robustness of the inference (it's called data science you may want to look it up).

http://www.realclimate.org/ind...

still have not seen any evidence that the feedbacks are positive, and I have looked...

You can do an experiment to prove the relationship in your basement. It's not like CO2 and H2O are hard to come by.

The main problem with the argument for positive feedbacks is if they were correct then at several times in the past the planet would have gone hot and killed off life...

Apparently you haven't bothered to look at why the Earth isn't at risk of runaway warming for the next billion years.

Models are shit, and only tell you what you have programmed into them, if you presume you must have positive feed back for certain values, you will set them like that and the model will tell you what you wanted to occur, caused by setting the parameters wrong.

You have no idea what you're talking about. The models are based on the laws of physics. Are they inaccurate? Of course, all models are -- even Relativity. All scientific knowledge is inaccurate. Does that mean we don't understand the laws of physics? If your measurement of your cannon's arc doesn't match the Newtonian projection, are you going to blame Newton or your measurement?

You don't seem to have a clue about much of anything, but maybe reading about simple climate models would help you be not as much a waste of oxygen.

James Hanson, the previous director of NASA GISS and Gavin's former boss, weighs in with his own perspective. In a comment to the post he says in part: There are various technical issues with both Schmittner and Snyder approaches that lead them toward their low and high values. Suffice it to say that I expect the true answer lie between the two, but closer to Snyder’s. The evidence favors a temperature change in the range ~4-5C for LGM-Holocene, and thus a fast-feedback climate sensitivity close to 3C or a bit larger. This then leads to an ESS sensitivity ~6C or somewhat higher as discussed in our 2013 paper. http://www.realclimate.org/ind...

According to Gavin Schmidt, the director of NASA Goddard Institute for Space Studies: "The paper claims that ESS is ~9C and that this implies that the long term committed warming from today’s CO2 levels is a further 3-7C. This is simply wrong." He goes on to show why: http://www.realclimate.org/ind...

The code is available here. Papers here. NASA uses station data compiled by NOAA GHCN v3 (meteorological stations), ERSST v4 (ocean areas), and SCAR (Antarctic stations),

According to the Director of the NASA Goddard Institute for Space Studies "Anyone can download it, run it for themselves and get the answer before we update our website every month."

I find it fucking hilarious that these jackasses are asking for the raw data when it's already available and has been available for years.

Next time some joker whines about raw data the answer will be: "Have you fucking looked?"

The code is available here. Papers here. NASA uses station data compiled by NOAA GHCN v3 (meteorological stations), ERSST v4 (ocean areas), and SCAR (Antarctic stations),

According to the Director of the NASA Goddard Institute for Space Studies "Anyone can download it, run it for themselves and get the answer before we update our website every month."

I've mentioned this before and they go on to tell me that it is expensive. Yeah? It's not like we have a choice in the matter and it's going to happen no matter how much shit we stuff in the air. No, really, it's going to happen and there's nothing we can do to stop it. All we can do is slow it down.

Sea level was dropping a few hundred years back. It seems to have abruptly reversed course shortly after the start of the industrial revolution: http://www.realclimate.org/ima...

Why do you think we are powerless?

the influence of el Niño and la Nina is actually fairly small on the global scale.
noticeable, but their largest effects are still localized, and decrease the further you go around the world.
and of course, the effects don't really start until midway or more through the year.

hence, the overall effect on global avg temps is relatively minor.
in fact, even without the el nino, it still would have been a record year.

http://www.realclimate.org/ind...

Eric Steig provides a good summary of our current understanding: http://www.realclimate.org/ind...

I think there's a fairly well accepted theory that the Antarctic land ice is melting quicker, reducing the salinity of the surrounding water, which helps to freeze the surface in the winter.

It's not so cut–and–dried. Eric Steig explains: "A basic problem, though, is that the greatest discharge of meltwater is occurring in the Amundsen Sea, exactly where sea ice is declining, so while this probably is part of the story, I doubt it’s very dominant." - http://www.realclimate.org/ind...

Where's the data?

Typically what happens is skeptics/doubters/deniers will say, "You're only showing us your processed data. Why don't you release the raw data?"

Then the climatologists say, "It's in the paper. We said which data we used, and where we got it. You can get it too."

Then the skeptics/doubters/deniers cry, "Why won't you just GIVE it to us! Why are you withholding the raw data??"

Raw data is available here: http://www.realclimate.org/ind...

graph

Yes, vindicated. For those of you who didn't click on link it shows the "enviro-left" IPCC predictions vs actual temperature measurements.

Oh, cute, an unsourced graph that stops in 2012 and uses dodgy frequently "adjusted" UAH satellite data.

Why not try it with actual temperature data and include recent measurements? Oh, because it doesn't tell the same story.

http://www.realclimate.org/images/compare_1997-2015.jpg

it was rising faster than it is now.

I think you mean 14 thousand years ago, not four thousand. The graph you posted shows the sea level rise 4 thousand years ago was about 3 centimeters per century-- a same rate that is pretty much constant for several thousand years. The link in the summary ( http://www.realclimate.org/ind... ) says since 1993 the rate has been 30 centimeters per century.

Here is an interesting article on the warming on Mars, 1999-2005. It implies the shrinking of the Martian southern ice cap is a regional phenomenon rather than being global. The comments following the article are interesting too including several rebuttals by the article author.

Yes the Mauna Loa observatory has the longest continuous record of atmospheric CO2 starting in 1958 but since then dozens of other observatories around the world have been measuring CO2 and not all of them are located next to volcanoes (La Jolla pier being one of them). Their results match the curve of the Mauna Loa observations so it doesn't appear that volcanic emissions of CO2 have had any effect on their measurements. There is a slight variance of CO2 levels by latitude with CO2 levels at the South Pole being a few ppm less than in the Northern Hemisphere but the general rise in atmospheric CO2 is evident in both places.

I suggest you read these FAQs on climate models before you continue.

FAQ on Climate Models
FAQ on Climate Models -- Part II

Not everything in climate models is physics based. Some things have to be parameterized because their scale doesn't fit the scale of the model. Different climate model runs start with slight variations in their starting points and run on 20 to 30 minute time steps to model chaotic weather within them so the output varies.

I suggest you read these FAQs on climate models before you continue.

FAQ on Climate Models
FAQ on Climate Models -- Part II

Not everything in climate models is physics based. Some things have to be parameterized because their scale doesn't fit the scale of the model. Different climate model runs start with slight variations in their starting points and run on 20 to 30 minute time steps to model chaotic weather within them so the output varies.

Hominids have exited on Earth for less than 10 million years so I don't consider anything before then, while interesting, to be particularly significant to our lives. Human civilization has existed for around 10,000 years. We know from history that civilizations have collapsed due to climate change. Although our present civilization is more resilient than they were it's not a sure thing that it will survive a drastic climate change.

Global temperatures for the last 11,800 years. Notice the sharp spike in the present.

there are others who try to duplicate the results

Please don't give us that Popper crap. Journals don't generally publish negative results do they. If you want to get published (and you usually do for career and funding reasons) there's a strong motivation to make sure you show what you set out to show. I would trust an area like physics more though, because it's so competitive and tightly focused. Everything else is up for grabs. Replicability of studies is pretty bad elsewhere.

No sorry, you are simply wrong. Your idea of scientists marching goosestep in lockstep, crushing any dissent, and deciding what the truth is and making certain no one strays from it is a ridiculous completel;y incorrect politically based view brought about by politically based people who simply are incapable of understanding that not everyone thinks as they do.

I've worked with scientists for 30 plus years. None of them fit your mold, and since anyone caught falsifying their research is instantly disgraced. Sometimes with terrible results, as when Yoshiki Sasai, the senior researcher who supervised and co-authored a falsified stem cell research paper, committed suicide by hanging himself. http://www.dailymail.co.uk/new... Haruko Obokata, the scientist who actually committed the fraud, had her doctorates degree rescinded by Waseda University. http://ajw.asahi.com/article/s...

The Italian group was not found engaging in fraud by politicians, Ir was other scientists who found them engaging in fraud.

The Japanese researcher who committed fraud was not found out by politicians, but by other scientists.

Remote sensing, the open access journal, found itself in a mess after Roy Spencer and Danny Braswell published a paper in it named, "On the Misdiagnosis of Surface Temperature Feedbacks from Variations in Earth’s Radiant Energy Balance” which in title alone raised some red flags since scientists seldom name reports that way, but http://www.realclimate.org/ind... It was debunked soon afterwards, retracted, and important questions raised about the impartiality of the journal raised due to it's benefactors. http://retractionwatch.com/201... Even a pro AGW paper linking Conspiracy ideation to denials has been retracted, scientists will go after anyone.

http://retractionwatch.com/2014/03/21/controversial-paper-linking-conspiracy-ideation-to-climate-change-skepticism-formally-retracted/ All of the scientists I have worked with take this kind of stuff seriously. Deadly seriously.

The "graph" you are referring to in the first IPCC report was a schematic diagram from Hubert Lamb with no scale on the y-axis. You can see it described as a schematic diagram in the IPCC's first archive report on page 202, Fig. 7.1. Also it is now known that the MWP was not a global phenomenon but was mostly limited to the the North Atlantic and Europe. Current science indicates the Little Ice Age was driven largely by volcanic activity with a small added impetus from the Maunder minimum. Solar activity has been low for a decade now yet temperatures continue to rise. What will be your response if as some predict solar activity remains low into the 2030s yet temperatures continue to rise?

I don't know where you got your 1.2 K ECS from (I suppose from Lewis & Curry) but the latest IPCC report give a range of 1.5-4.5 K for ECS. Gavin Schmidt has an interesting commentary on Reconiciling estimates of climate sensitivity over at RealClimate talking about the recent Kate Marvel paper in which he had a part.

It might be, but I'm AC and always have been, and I'm usually on the "yes, it's warming, and probably from human activities" side of this particular issue. I'm usually the one pointing out that even if "climate change is normal throughout geological history", this scale of change in a couple of centuries is unusual. I mean, we've basically gone from 280ppm to 400ppm, and the isotopic composition of the CO2 now in the atmosphere makes it pretty clear that a lot of ancient carbon is getting up there somehow. Burning of fossil fuels is a fairly obvious explanation. Pretty good explanation here, more succinct [here](http://scitation.aip.org/content/aip/magazine/physicstoday/article/58/5/10.1063/1.1995728). Unless people are claiming that increasing CO2 concentration doesn't increase the greenhouse effect (which kind of defies basic atmospheric physics), it's a pretty strong connection. Perfect, no, there's room to argue about how much of it is anthropogenic (i.e. what fraction), but it seems clear to me that a sizable chunk of it is.

Anyway, I think you are underestimating how many people are opinionated and maybe even knowledgeable, but who don't want to post non-anonymously. It's a contentious issue, which provokes comments including by ACs.

It's very unlikely that people would be "paid by the oil industry" to spin in a place like slashdot. More likely they'd be lobbying politicians or influencing media that are more likely to have an effect on the kind of demographic that would find such a spin attractive. It's interesting to speculate about some kind of concerted effort, but I think it's more likely that there are a decent number of people who are independently and honestly in denial.

The problem that I have with anthropogenic global warming is that it started out sounded like a science-based issue, but it has since moved into the realm that's more reminiscent of a religion (complete with established dogma, punishment of heretics, an apocalyptic theology, etc.).

It's easy to have this perception if you haven't really been following the details of the debate, other the bowdlerized version in the (now emasculated) press.

The debate goes back over a hundred years. AGW was well and thoroughly debunked in the early 20th century, and on solid scientific grounds. For example it was "known" that CO2 was in equilibrium between the oceans and the atmosphere; the bulk of any increase in atmospheric CO2 would be absorbed into the oceans.

So what happened? Well, lots of things. Oceanographers went out and observed the ocean and realized that it's buffering capacity was much less than thought. We gained access to the upper atmosphere, which debunked the scientific consensus that increases in surface temperature would get mixed away. In the 50s we got the technology to make precise enough measurements of atmospheric CO2 to track its increase. And from the 60s on we gained the ability to track and correlate large bodies of data whereas researchers until then were limited to manually processing small quantities of data with pencil and paper. That's the most important point and I'll come back to it in a moment.

AGW became a political issue when An Inconvenient Truth came out in 2006, and it seemed to many of us like everything we learned about climate in our obsolete 1960s textbooks was being tossed out overnight. But it wasn't overnight. If you go back and follow the debate from the mid-50s using Google Scholar you'll see it took almost four hard-fought decades for the overwhelming consensus of scientific opinion to shift from against to in favor of AGW.

Well, what about the "dogmatic" dismissal of all the evidence against AGW? Well, complex systems always generate contradictory-looking data points. Let's say we tracked the state of the retail economy heading into the Great Depression by following a single representative company: Woolworths. The worse people said things were getting in "the economy", the more out of touch with reality they'd seem to us to be: Woolworth's gross sales in the so-called "Great Depression" kept going up. But if you looked at the big picture consumer spending had plummeted by 25% and retail prices had taken a nose dive, and this explains while Woolworths was thriving; it was displacing traditional retailers with higher overhead that couldn't survive the shock.

Much of the "debunking" climate data -- where it stands up to scrutiny -- is of this sort. For example take a look at this graph of temperatures in Greenland. The temperature spike you see at 1000 YBP is the famous "Medieval Warm Period", and if you go back to 7000 YBP and 8000 YBP it was even warmer. So does that disprove that the world is getting warmer? Are climate scientists who shrug this off being dogmatic?

No, because Greenland isn't the whole world; nor is the North Atlantic region that warmed in the MWP. This gets back to my point about data processing; you need to crunch a lot of data to get the global picture, which as far as we know looks like this.

It seems dogmatic if scientists don't believe what we want to be true and which we can back up with evidence. But there's always evidence in something like climate to support any position you'd like to take. It's the pattern of evidence that matters.

With your having a stronger math background and an interest in the subject, would you be willing to comment on this exchange? Basically the back and forth between Mcshane and Wyner(statistics) debating with Michael Mann and co over the later's usage of statistical methods in his proxy reconstructions.

I only picked up a minor in Math, but reading the back and forth it sure feels to me like Mann is dismissing or glossing over some pretty important criticisms levelled:
The process by which the complete set of 95/93 proxies is reduced to 59/57/55 is only suggestively described in an online supplement to Mann et al. (2008). As statisticians we can only be skeptical of such improvisation, especially since the instrumental calibration period contains very few independent degrees of freedom. Consequently, the application of ad hoc methods to screen and exclude data increases model uncertainty in ways that are unmeasurable and uncorrectable ...

The appearance of a difference in SMR Figure 1a is especially magnified because those reconstructions are smoothed. Smoothing exaggerates the difference and requires careful adjustment of fit statistics such as standard errors, adjustments which are lacking in SMR and which are in general known only under certain restrictive conditions. In contrast, consider the right panel of Figure 1 which is a reproduction of SMR Figure 1a without smoothing. The difference between a given model fit to the full dataset or the reduced data set is clearly dwarfed by the annual variation of the fit; the full and reduced set of proxies yield inconsequentially different reconstructions. ...

Additionally, SMR make no attempt to grapple with standard errors.

Many of your questions are answered here, with links provided to further data. If you'd like more in-depth information about the exact process, why not contact an actual climatologist? There are some around who are taking the time to talk to the public, e.g. at RealClimate.

The trick is that they are only useful for testing out how things work under a given energy imbalance or energy conditions. They are NOT useful for hindcasting energy imbalance

The source for the quoted nonsense above is WUWT, one of many denier/front sites funded by the (untaxed) anti-science lobbyists at the .

The fact is that hindcasting is how climate models are tested, how else would anyone test it? You can find the code for several important models here and run it yourself for the price of a decent server.

Not only can we model the evolution of Earth's past climate and routinely hindcast the last 500yrs with high levels of "model skill", we can also model the evolution of climate on other planets, in particular Mars and Venus. Here's a reliable and independent source that talks about hindcasting climate for testing purposes.

Note also that the uncertainty you quote is about cloud cover, the other common cherry pick used in this kind of FUD is the uncertainty surrounding the behaviour of ice. These two KNOWN uncertainties are discussed in great detail in the report you linked to. They are responsible for what scientists call "error bars". The WG1 report is however the best summary of the current state of climate science that anyone has to offer. If you want to debunk climate science that is the primary document to attack, it is the embodiment of the so called "consensus", good luck in your studies.

You are so wrong it's almost comical. As I already stated in my post as well as providing a link, the source for this is the IPCC WG1 you champion in your own retort:
Model tuning aims to match observed climate system behaviour and so is connected to judgements as to what constitutes a skilful representation of the Earth’s climate. For instance, maintaining the global mean top of the atmosphere (TOA) energy balance in a simulation of pre-industrial climate is essential to prevent the climate system from drifting to an unrealistic state. The models used in this report almost universally contain adjustments to parameters in their treatment of clouds to fulfil this important constraint of the climate system

As you state yourself, knock yourself out debunking it. The fact is that the errors from unknowns like clouds leaves hind casting that runs into unrealistic states unless you correct it manually. The seem to agree the source is sound, so not sure what your problem is aside from the conclusion maybe not being as open and shut as you'd like,

The trick is that they are only useful for testing out how things work under a given energy imbalance or energy conditions. They are NOT useful for hindcasting energy imbalance

The source for the quoted nonsense above is WUWT, one of many denier/front sites funded by the (untaxed) anti-science lobbyists at the .

The fact is that hindcasting is how climate models are tested, how else would anyone test it? You can find the code for several important models here and run it yourself for the price of a decent server.

Not only can we model the evolution of Earth's past climate and routinely hindcast the last 500yrs with high levels of "model skill", we can also model the evolution of climate on other planets, in particular Mars and Venus. Here's a reliable and independent source that talks about hindcasting climate for testing purposes.

Note also that the uncertainty you quote is about cloud cover, the other common cherry pick used in this kind of FUD is the uncertainty surrounding the behaviour of ice. These two KNOWN uncertainties are discussed in great detail in the report you linked to. They are responsible for what scientists call "error bars". The WG1 report is however the best summary of the current state of climate science that anyone has to offer. If you want to debunk climate science that is the primary document to attack, it is the embodiment of the so called "consensus", good luck in your studies.

Anyone who genuinely wants to debunk global warming should start here, trust me, climate scientists will respond with collective sigh of releif should anyone succeed.

RealClimate.org maybe wouldn't be the best place to start. There's a lot of very aggressively close minded chaps dominating the forums. I know, who'd have thought that could happen on an internet forum?

Real climate is also co-founded by Michael Mann, whom I really take some issue with. Tell me I'm making a mountain out of a mole hill, but his paleo reconstructions of temperature have really bothered me in the past. Nothing to do with the results, not as much to do even with his methodology now that his later work is addressing and correcting problems. The presentation and usage of the 'hide the decline' trick in graphs is just disgusting. When your paleo reconstruction ends around 1900, just end the graph there. If your paleo reconstruction doesn't show the same temperature rise since 1900 as instrumental, then show that too. What you DO NOT DO, is paste in the instrumental record with a thick enough line to hide the paleo reconstruction since 1900. Even further, don't point to the overlapped instrumental part of the graph as startling and clear evidence of an abrupt trend in the data starting at 1900.

If your wanting to have an open and honest discussion about the evidence, that's a difficult environment. Even scientists with a decent publishing record within the field like Lindzen are put under a microscope for criticism for not conforming to the 'consensus'. Even researchers widely embraced and accepted like Mauritsen have their results heavily disputed and interpreted there. When statisticians like McShane and Wyner take issue with the statistical methods in Mann and others work, Mann takes to his blog for the 'final' word while leaving out any response to their real and legitimate questions and arguments. I'm not anticipating that it's going to be a particularly receptive audience as you seem to believe.

Anyone who genuinely wants to debunk global warming should start here, trust me, climate scientists will respond with collective sigh of releif should anyone succeed.

RealClimate.org maybe wouldn't be the best place to start. There's a lot of very aggressively close minded chaps dominating the forums. I know, who'd have thought that could happen on an internet forum?

Real climate is also co-founded by Michael Mann, whom I really take some issue with. Tell me I'm making a mountain out of a mole hill, but his paleo reconstructions of temperature have really bothered me in the past. Nothing to do with the results, not as much to do even with his methodology now that his later work is addressing and correcting problems. The presentation and usage of the 'hide the decline' trick in graphs is just disgusting. When your paleo reconstruction ends around 1900, just end the graph there. If your paleo reconstruction doesn't show the same temperature rise since 1900 as instrumental, then show that too. What you DO NOT DO, is paste in the instrumental record with a thick enough line to hide the paleo reconstruction since 1900. Even further, don't point to the overlapped instrumental part of the graph as startling and clear evidence of an abrupt trend in the data starting at 1900.

If your wanting to have an open and honest discussion about the evidence, that's a difficult environment. Even scientists with a decent publishing record within the field like Lindzen are put under a microscope for criticism for not conforming to the 'consensus'. Even researchers widely embraced and accepted like Mauritsen have their results heavily disputed and interpreted there. When statisticians like McShane and Wyner take issue with the statistical methods in Mann and others work, Mann takes to his blog for the 'final' word while leaving out any response to their real and legitimate questions and arguments. I'm not anticipating that it's going to be a particularly receptive audience as you seem to believe.

Anyone who genuinely wants to debunk global warming should start here, trust me, climate scientists will respond with collective sigh of releif should anyone succeed.

RealClimate.org maybe wouldn't be the best place to start. There's a lot of very aggressively close minded chaps dominating the forums. I know, who'd have thought that could happen on an internet forum?

Real climate is also co-founded by Michael Mann, whom I really take some issue with. Tell me I'm making a mountain out of a mole hill, but his paleo reconstructions of temperature have really bothered me in the past. Nothing to do with the results, not as much to do even with his methodology now that his later work is addressing and correcting problems. The presentation and usage of the 'hide the decline' trick in graphs is just disgusting. When your paleo reconstruction ends around 1900, just end the graph there. If your paleo reconstruction doesn't show the same temperature rise since 1900 as instrumental, then show that too. What you DO NOT DO, is paste in the instrumental record with a thick enough line to hide the paleo reconstruction since 1900. Even further, don't point to the overlapped instrumental part of the graph as startling and clear evidence of an abrupt trend in the data starting at 1900.

If your wanting to have an open and honest discussion about the evidence, that's a difficult environment. Even scientists with a decent publishing record within the field like Lindzen are put under a microscope for criticism for not conforming to the 'consensus'. Even researchers widely embraced and accepted like Mauritsen have their results heavily disputed and interpreted there. When statisticians like McShane and Wyner take issue with the statistical methods in Mann and others work, Mann takes to his blog for the 'final' word while leaving out any response to their real and legitimate questions and arguments. I'm not anticipating that it's going to be a particularly receptive audience as you seem to believe.

Anyone who genuinely wants to debunk global warming should start here, trust me, climate scientists will respond with collective sigh of releif should anyone succeed.

RealClimate.org maybe wouldn't be the best place to start. There's a lot of very aggressively close minded chaps dominating the forums. I know, who'd have thought that could happen on an internet forum?

Real climate is also co-founded by Michael Mann, whom I really take some issue with. Tell me I'm making a mountain out of a mole hill, but his paleo reconstructions of temperature have really bothered me in the past. Nothing to do with the results, not as much to do even with his methodology now that his later work is addressing and correcting problems. The presentation and usage of the 'hide the decline' trick in graphs is just disgusting. When your paleo reconstruction ends around 1900, just end the graph there. If your paleo reconstruction doesn't show the same temperature rise since 1900 as instrumental, then show that too. What you DO NOT DO, is paste in the instrumental record with a thick enough line to hide the paleo reconstruction since 1900. Even further, don't point to the overlapped instrumental part of the graph as startling and clear evidence of an abrupt trend in the data starting at 1900.

If your wanting to have an open and honest discussion about the evidence, that's a difficult environment. Even scientists with a decent publishing record within the field like Lindzen are put under a microscope for criticism for not conforming to the 'consensus'. Even researchers widely embraced and accepted like Mauritsen have their results heavily disputed and interpreted there. When statisticians like McShane and Wyner take issue with the statistical methods in Mann and others work, Mann takes to his blog for the 'final' word while leaving out any response to their real and legitimate questions and arguments. I'm not anticipating that it's going to be a particularly receptive audience as you seem to believe.

Yes, they claim to have found a slight accounting error in the work that attributes the inputs for the observed sea level rise, it was found with new satellites, improved data resolution, and longer time scales. That small portion of the rise must now be accounted for 'elsewhere', it probably won't be until we make similar measurement improvements 'elsewhere'. Remove the politics and this paper is only interesting to beancounter geeks, it does not challenge existing theories or observations, let alone disprove them. Most importantly, it does not change the observed sea level rise.

This paper is actually a continuation of the valuable and ongoing work that the 'climategate' beat up was desperately trying to discredit and disrupt via character assassination. ie - Robust climate data. Climate data sets are collected, cleaned, maintained and published by NASA and other organisations, here's a list of the main data sets used by climate researchers. The IPCC does not perform or fund research or data collection, it summarises existing peer-reviewed publications into various reports aimed at different audiences.

Anyone who genuinely wants to debunk global warming should start here, trust me, climate scientists will respond with collective sigh of releif should anyone succeed.

Dyson has succeeded in destroying his reputation as a serious and credible observer and commentator of society and his times by propagating pseudo-science around climate change. His actual scientific achievements are of course spared.

Freeman Dyson is not a climate scientist. He's a scientist who dabbles in theorizing about the climate because he wants to. He is trading on his name and reputation, to the detriment of both. It doesn't matter how smart you are or how accomplished you are in other areas; if it's not your specific area of expertise, then you're in over your head.\

If you want to see Dyson's theorizing on climate systematically and thoroughly destroyed - (amongst other things he gets caught in just plain old logical fallacies) by actual climatologists, here's what that looks like:

http://www.realclimate.org/ind...

https://www.skepticalscience.c...

http://initforthegold.blogspot...

https://www.skepticalscience.c...

https://www.skepticalscience.c...

This is hilarious. NY isn't sinking. Overall global sea level rise has REMAINED at about 1mm/year for about 300 years. [Lonny Eachus, 2015-09-05]

Avg. sea lvl. rise has been about 0.9-1.0 mm/year for centuries. It rose a bit faster part of 20th Cen., but some say it's DEcelerating. [Lonny Eachus, 2015-09-04]

Lonny backpedals away from his stronger claim that sea level has been rising at "exactly the same rate for 300 years."

How did Lonny read the first sentence in Houston and Dean 2011 stating that sea level rose by 1.7mm/y over the 20th century, but not admit that it contradicts his mistaken claim about "< 1mm per year rate for hundreds of years"?

It's especially amusing that Jane/Lonny cites the exact paper which was already debunked in the links I've repeatedly given him. Since the code I just gave Jane/Lonny reproduces figure 2 in Rahmstorf and Vermeer 2011, Lonny already had all the code and data he needed to see that Houston and Dean 2011 had been prebunked for years.

Even Houston and Dean said "there is consensus among the authors that sea level accelerated from 1870 to 2004." They just cherry-picked 1930, the starting point with the lowest best-fit acceleration. Then they pretend to question if "sea level has accelerated during the 80 years from 1930–2010" and somehow ignore the fact that best-fit accelerations are even higher starting after 1930.

On top of that, anyone who cites Houston and Dean 2011 to support a claim that global sea level is "DEcelerating" should be aware that this is the result of a simple mistake where they neglected to take into account the fact that the southern hemisphere has more ocean than the north. When Rahmstorf and Vermeer 2011 corrected their error, the best-fit acceleration was positive.

The most hilarious bit, however, might be their response to these corrections. Houston and Dean had selectively cherry-picked a single starting date of 1930, then Rahmstorf and Vermeer calculated figure 2. Like my figure on page 2, Rahmstorf and Vermeer didn't selectively cherry-pick a starting year like Houston and Dean did. Quite the opposite!

How do Houston and Dean respond? They actually complained that Rahmstorf and Vermeer were somehow being "selective". This brazen reversal of the facts might have surprised me before I saw Jane baselessly accuse Layzej of cherry-picking for loading the entire UAH dataset, then Jane suggested only using data since 1998 and kept demonstrating that he would never grasp that irony.

If Jane/Lonny really had "many counterexamples", it's strange that he cited the one paper that had already been repeatedly prebunked and another regional paper which Houston and Dean cited while trying to explain away the fact that the southern hemisphere has more ocean than the north. Again, Lonny doesn't seem likely

This is hilarious. NY isn't sinking. Overall global sea level rise has REMAINED at about 1mm/year for about 300 years. [Lonny Eachus, 2015-09-05]

Avg. sea lvl. rise has been about 0.9-1.0 mm/year for centuries. It rose a bit faster part of 20th Cen., but some say it's DEcelerating. [Lonny Eachus, 2015-09-04]

Lonny backpedals away from his stronger claim that sea level has been rising at "exactly the same rate for 300 years."

How did Lonny read the first sentence in Houston and Dean 2011 stating that sea level rose by 1.7mm/y over the 20th century, but not admit that it contradicts his mistaken claim about "< 1mm per year rate for hundreds of years"?

It's especially amusing that Jane/Lonny cites the exact paper which was already debunked in the links I've repeatedly given him. Since the code I just gave Jane/Lonny reproduces figure 2 in Rahmstorf and Vermeer 2011, Lonny already had all the code and data he needed to see that Houston and Dean 2011 had been prebunked for years.

Even Houston and Dean said "there is consensus among the authors that sea level accelerated from 1870 to 2004." They just cherry-picked 1930, the starting point with the lowest best-fit acceleration. Then they pretend to question if "sea level has accelerated during the 80 years from 1930–2010" and somehow ignore the fact that best-fit accelerations are even higher starting after 1930.

On top of that, anyone who cites Houston and Dean 2011 to support a claim that global sea level is "DEcelerating" should be aware that this is the result of a simple mistake where they neglected to take into account the fact that the southern hemisphere has more ocean than the north. When Rahmstorf and Vermeer 2011 corrected their error, the best-fit acceleration was positive.

The most hilarious bit, however, might be their response to these corrections. Houston and Dean had selectively cherry-picked a single starting date of 1930, then Rahmstorf and Vermeer calculated figure 2. Like my figure on page 2, Rahmstorf and Vermeer didn't selectively cherry-pick a starting year like Houston and Dean did. Quite the opposite!

How do Houston and Dean respond? They actually complained that Rahmstorf and Vermeer were somehow being "selective". This brazen reversal of the facts might have surprised me before I saw Jane baselessly accuse Layzej of cherry-picking for loading the entire UAH dataset, then Jane suggested only using data since 1998 and kept demonstrating that he would never grasp that irony.

If Jane/Lonny really had "many counterexamples", it's strange that he cited the one paper that had already been repeatedly prebunked and another regional paper which Houston and Dean cited while trying to explain away the fact that the southern hemisphere has more ocean than the north. Again, Lonny doesn't seem likely

10 meters is almost 33 feet. 1000 years is within the historical record. If there had been sea level change anywhere close to that amount it would be slap you in the face obvious. Show me some historical evidence for that much sea level drop. Are there Roman ports that are now 33 feet above sea level? Do historical records from China or Japan show anything like that? 10 meters of sea level drop over the last 1000 years is impossible to support.

Here's a story on a detailed study of sea levels over the last 2000 years done on the North Carolina coast that doesn't show anything like 10 meters of change.

Maybe you should get up to HS level chemistry. The Ocean is a _buffered_ solution. Which makes it require an order of magnitude more of anything to change it's ph past the buffer levels.

Yes, but the buffering is provided by Ca ions, which means that the ph is not the issue, but rather what happens to the CaCO3 equilibrium. There is a nice description with citations here. That summary also points out that bleaching is a bigger problem for coral than acidification, but TFA is about studying the impact of this chemistry on other life forms.

But my original point was that this stuff is not extraordinary science, and your adding Le Châtelier into the mix only moves the needle by about 20 years to the late 1800s...

(Oddly, enough, the same kid is taking HS chemistry this year, so I'll get to brush up a bit, but it is surprising what you can remember from 40 years ago when breakfast this morning is a mystery!)