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jgnfld - There certainly is autocorrelation observed in the temperature record, which can be characterized as ARMA(1,1) in nature (Foster and Rahmstorf 2011, Appendix on Methods). A signal of that nature can easily show >15 year negative trends as variation over an underlying positive trend, as discussed at the end of this post with artificial data.
In addition, the GCMs produce much the same behavior from the physics, demonstrating autocorrelation and in effect inertia in variations. So the statement is entirely reasonable.
Thanks Tom a very informative video from Kevin Cowtan. That software he is using is pretty cool. VERY clever. Good of Kevin to take the time. Could I just mention something. KC makes reference to 1970 & 2005 'temperature drop' doesn't Berkeley Earth flag those two periods as 'station moves'? I noticed that in the ATTP link 'scaddenp' posted #333
Re.: "A period of cooling due to incidental variations in the climate
The climate knows random variations. Strengers wrote that these may lead to longer periods of no warming or even cooling, even under a steady increase in greenhouse gas concentrations in the atmosphere. During the discussions, Strengers pointed to a study which shows on the basis of climate models that periods of up to 16 years of random cooling or non-warming may occur, even in an overall warming climate." it may just be I'm not reading this right, but this seems to suffer from Gambler's Fallacy reasoning. That is unless he is invoking autocorrelation which does, in fact, allow such reasoning.
China sulfate emissions reductions from 2009 are also a major contributor to the recent warming trend. The secondary cloud effects appear to be at the higher end of the uncertainty spectrum (more negative).
" the degree of warming according to the UAH series, which is based on satellite measurements, was 0.1 °C over the last 5 years, compared to the mean of the 10 years before that. If this trend continues over the coming 5 years, our current decade will register a warming of around 0.15 °C"
(From the second-to-last paragraph.)
I don't follow this. If we had .1 degree warming over the first five years, would we expect .2 degees over the decade "if the trend continues"?
Also, I was surprised to see no mention of volcanoes. Couldn't a major volcano eruption have through a major spanner into these rather short-term predictions?...
ranyl asks: "...do we actually have a carbon debt rather than a budget already?"
You rightly highlight that there are papers suggesting a low CS recently and that given all thign matural we should be cooling, however have you also considered the several papers than suggest the CS might be higher than thought at ~4C but less than 5C and greater than 3C.
"The mixing inferred from observations appears to be sufficiently strong to imply a climate sensitivity of more than 3 degrees for a doubling of carbon dioxide. This is significantly higher than the currently accepted lower bound of 1.5 degrees, thereby constraining model projections towards relatively severe future warming."
Steven C. Sherwood, Sandrine Bony & Jean-Louis Dufresne, "Spread in model climate sensitivity traced to atmospheric convective mixing" Nature 37, vol 505, 2 January 2014
In medical practice a 95% chance of success is generally considered reasonably safe when taking actions, 99% is preferable and less than this and things became deemed quite risky.
Therefore shouldn't we be considering, what is the CO2 accumulative emissions amount that would give a 95% chance of avoiding greater than a 2C in the next 100 years?
And if the evidence in the paper holds true, (which is likely considering all that heat going into the oceans etc.) then the range for CS would start at 3C and end at 5C. A shift in the CS range of that nature would significantly reduce the carbon budget estimations currently being made for policy makers to ponder.
Further maybe we should even be asking what is the total GHG emissions that gives a 95% chance of keeping earth lower than 2C for the next 300 years, given that prevention is better than cure for future generations?
And is 2C even safe?
As the only way to actually turn the CO2 heater down is to remove CO2 from the atmosphere, do we actually have a carbon debt rather than a budget already?
Fossil fuels are from plants, its true, but that carbon was removed from the air hundreds of millions of years before humans ever walked the earth. So releasing that carbon isn't neutral from the perspective of human history or civilization. In addition, burning all of the fossil fuels would return us to a truly ancient pre-human atmospheric chemistry, with all its attendant consequences for climate, in only a only century or two, whereas it took many millions of years to stash away that carbon in the earth in the first place.
The CO2 we exhale, on the other hand, was usually taken from the atmosphere in the last year or two. The uptake of that carbon from the air by food crops contributes fractionally to the regular annual fluctuations in atmospheric CO2. Over scales longer than a year, the net effect on climate of carbon dioxide uptake by food crops and exhalation of CO2 by people is essentially zero.
Using your reasoning about humans being neutral in terms of CO2. Following that logic the burning of fossil fuels can be deemed neutral as well. Oil and coal are derived from plants. They just happen to be sequestered in the ground. Its interesting though once taken out of the ground they still don't add to the increase in CO2 as they are in a liquid or solid state. Not unitl they are "burned" do they release CO2. I wonder if that is the same for humans, whether you should be buried or sequestered?
ryland @various, my argument is not with the Met Office. It is with the pseudo-skeptics who created a furror when (according to them) GISS announced that 2014 was a record year without qualification. The simple fact is that 2014 is the record year in the GISSTEMP temperature index. As it happens, the GISS announcement actually discussed the uncertainty in greater detail than has the HadCRUT4 announcement. They just did not use the form of words that the pseudoskeptics wanted. What is worse about some pseudoskeptics is that when knowledge of the table shown @36 became available, they treated it as a subsequent announcement, as a backdown, and as proof that 2014 was not the record year. Each of those claims was false, and the first two grossly misrepresent the communications from NASA GISS.
Beyond the political agenda of those pseudoskeptics, what is going on here is that people are confused by what is meant by "record x". The record x, for whatever x is, is simply the highest value in the record. The Guiness Book of Records, for example, does not claim that the car that currently holds the land speed record was the fastest ever car. It simply claims that it is has the fastest speed entered in the records. Other cars may have been faster, but been excluded because of the presence of a strong tail wind, the failure to run the test in both directions within a given time limit, or the simple absence of an official observer. They do not even take note of potential error margins in observations which are certainly there, although I do not claim they are significant. Likewise when reporting on the fastest delivery in cricket, nobody worries about the uncertainties in measurement. Indeed, when record cold winters for the US are announced, the pseudoskeptics definitely do not draw attention to uncertainties (which are even more of a factor). They just accept face value, or distort the figures.
So, 2014 is the warmest year in the GISS record, and the warmest year in the HadCRUT4 record, and the warmest year in the NOAA record, and the warmest year in the BEST record. That does not mean it was in fact warmer than 2010, because the measurement of GMST is uncertain - but it is the record year for each of those temperature indices.
Further, distracting from that fact by saying it may not have been the record year is pure obfustication. With HadCRUT4 (having now actually run the numbers), if you allow that obfustication there have been just 3 record years (1850 (by definition), 1990, and 1998), rather than the 15 record years that have actually occurred - 9 of them since 1983 (inclusive); and 4 of them since 1998 (inclusive). (Full list at end of post.) Further, the obfustication means that, if we accept the distorted terminology, the most recent "record year" is 1998, even though 1998 has a very low probability of being the actual hottest year in the last 150 years according to HadCRUT4, (and is "statistically excluded" according to BEST).
The way climate deniers are currently objecting to this latest record hot year, yes, that's what they're going to do. You'd have to have an extreme record to have the uncertainty fall above the uncertainty range of all previous years.
And, 4C+ is a reference to business-as-usual emissions path leading to a 4C or better rise in surface temperatures over pre-industrial levels by 2100.
I really don't think that will happen as I'm sure at some stage the global temperature of a particular year will be statistically different from the temperature in other years. In any event how important is it for a particular year to be called the "hottest ever"? Apologies but I don't know what you mean by surface temps rise to 4C+.
AFAIK, most changes in data records are either due to changes in sensor type (like going from mercury in glass to electronic sensors) or changes in hour of recording (including how to calculate daily averages). In a particular country, this (a break in teh record) was then probably due to a nationwide switch made by the national body in charge of those measurements. Have to ask our South American readers here to chime in ...
Think it through, though. The way this is all suddenly being re-defined means that there will never be any new record warm years. There will likely always be some statistical likelihood (however small) that another year was actually warmer.
So, now climate deniers can go all the way through the rest of the century stating that no year has been the warmest year, even as surface temps rise to 4C+.
Thanks Rob Honeycutt for actually addressing what te UK Met Office is saying. Yes I agree they are being cautious but, as I'm sure you know, when submitting a paper for publication, to ehance your chances with the reviewers it is usually better to err on the side of caution. From the new post on SkS the bet wasn't scrubbed as the stats weren't conclusive shows that the two bettors didn't really care and fair enough too in the context of the bet. That said however I do think that accepting the constraints on conclusions placed by adhering to the results of statistical analysis is preferable to disregarding the stats
ryland... You may take note that the Met Office was the last to report the 2014 record. They waited (as far as I can tell) to see what responses came out from the other data sets.
In my opinion, the Met Office is taking an overly cautious approach to their statement. The NASA/NOAA folks took the extra step to point out the relative likelihood of each year being a record. In both sets 2014 stands out as being the most likely to be the warmest year. The Met Office soft peddled and merely stated that 2014 is "one of the warmest years" whereas, per Tom's comments above, it's quite clear that 2014 is by far the most likely to be the warmest.
The only thing you're managing to point out is the fact that the Met Office has been more restrained in their definition. That's fine if that's how they want to approach the issue.
The biggest point remains that 2014 was a ENSO neutral year and still managed to statistically beat all the other previous El Nino forced record years.
As I tried to make plain in my response to Tom Curtis, I personally, do not have any particular stance on the record heat or otherwise of 2014. The text in my first post (@44) was taken directly from the UK Met Office. Your comments should be directed to the UK Met Office, possibly to Dr Colin Morice, as it is their words to which you take exception. All I did, mistakenly it seems, was to draw attention to a statement by a very reputable institution full of "reality based people" that was somewhat at odds with the title of this particular topic. Why do you and others not address what the Met Office is saying?
Ryland's way of arguing is common and unfortunately typical of a certain mindset. Looking at temperatures in recent years, it is painfully obvious that there is no pause in the warming, and never was. This argument was only made possible by the 1998 whopper year and every drop of nonsense has been squeezed out of it by fake skpetics. Because the trend is still there, every 5 years the argument becomes more stupid. Now they turn the stupid argument inside out and squeeze it the other way to get more out of it. Inevitably, there will be a year in the near future that will be statistically significant way above 1998, but not 2014, so we'll have more quibbling about words and ridiculous hair splitting, just like here. All because the reality based people are actually being honest and describing facts accurately. You can't win with dishonest people. Even if you do, they'll say you didn't. Wrestling in the mud with pigs...
Every record year makes me more disgusted with the reality of this "debate."
ryland, 2014 has the highest probability of being the warmest year.
This complaint reminds me of the denier Paul Merrifield (aka "mememine") who has filled the internet with the claim that since the IPCC was not using the language of certainty, then they weren't really sure at all. They were just guessing. As long as the public understands uncertainty in the crudest way, the denier program is in control.
Let's hope that GMST remains in that complainable gray area where the uncertainty is greater than the difference between years. Unless it goes down, of course, and that doesn't seem probable . . .
Tom Curtis I'm not making any decisions at all about whether or not 2014 was or was not the hottest year but the UK Met Office certainly is. The scientists there are making the point that as the uncertainties in the estimates of global temperatures are greater than the difference in temperatures between years then it is not possible to say definitively that 2014 was the hottest year ever. Are they wrong in this?
With regard to your point "because it is not statistically certain that it was the hotest, you are simply declaring that no year is the record year" again I'm not declaring anything but again, the UK Met Office certainly is. Their comment "Nominally this ranks 2014 as the joint warmest year in the record, tied with 2010, but the uncertainty ranges mean it's not possible to definitively say which of several recent years was the warmest" Are they wrong to make this statement?
And as for making a big deal of it surely the Met Office are to be commended for making a statement that is correct based on the statistical analysis of their results. Should they have ignored that analysis?
And as these statements are coming from the UK Met Office itself your comment they are "signs of desperation by people whose message is coming unstuck in the face of new data" is perhaps not entirely appropriate.
[Rob P] - Whether or not 2014 was the warmest year recorded in the Hadley surface temperature data is not the really the most interesting aspect. The main takeaway is that global surface warming is still continuing. This is very obvious in the Hadley data:
ryland @44, the HadCRUT4 dataset shows 2014 to have had a temperature anomaly of 0.563 C (final column). That beats 2010 (0.555 C), 2005 (0.543 C), 1998 (0.535 C) and 2003 (0.507 C). As a matter of curiousity, 2014 is the only one of those top five years not to fall on an El Nino year. So, clearly 2014 is the record year in the HadCRUT4 dataset. It is possible that the actual global temperature was warmer in another year, but the probability of being the record year is stronger for 2014 than for any other year. Therefore, while that it is not statistically certain that 2014 was the warmest should be noted simply on the basis that we should always note uncertainties in observations; it is not relevant. Making a big deal about it shows signs of desperation by people whose message is coming unstuck in the face of new data.
I note that if you (or anybody else) decide that 2014 is not the record year because it is not statistically certain that it was the hotest, you are simply declaring that no year is the record year, for the same was true of 1998, 2005, and 2010 when they set the records; and the same will almost certainly be true for every new record into the future. That should show how empty is the denier rhetoric on this point.
From the UK Met Office release on Jan 26th It may be that 2014 was not in fact the warmest ever. The Met Office stated:
The HadCRUT4 dataset (compiled by the Met Office and the University of East Anglia's Climatic Research Unit) shows last year was 0.56C (±0.1C*) above the long-term (1961-1990) average.
Nominally this ranks 2014 as the joint warmest year in the record, tied with 2010, but the uncertainty ranges mean it's not possible to definitively say which of several recent years was the warmest.
Colin Morice, a climate monitoring scientist at the Met Office, said: "Uncertainties in the estimates of global temperature are larger than the differences between the warmest years. This limits what we can say about rankings of individual years.
"We can say with confidence that 2014 is one of ten warmest years in the series and that it adds to the set of near-record temperatures we have seen over the last two decades."
And this is how a Yaley Skull and Bonesman established an economic analysis pattern that would justify the use of outrageously high multi-generational discout rates. By asserting the kind of unlimited growth projections that were previously found only with the "Chicago Boys" who were advocating total economic dismantling of Chile under the ruthless dictator Pinochet.
If (when?) we reach 3.5 C of globally averaged warming, there will be only a small shadow of the former global human civilization since mass migrations, sea level rise and wars, famines and plagues have destroyed most of the global infrastructure.
Were these real impacts incorporated in the models, the reduction in global output would justify a negative discount rate. But you aren't going to get that from Yale.
Not to pile on here... but I believe PaxInterra's response is more an emotional one than a fact based one. If KXL were not important to the extraction rate of the tar sands, then they really wouldn't care. As it is, investors are pulling out of tar sands projects because it's looking less profitable. If we can get carbon taxes installed, then those FF sources of energy become less competitive and tar sands become even less attractive.
There are lots of reasons to have a positive outlook on how things are going to play out in the coming 10-15 years. Taking a defeatist attitude only plays into the hands of the FF industry.
PaxInterra - We certainly need to engage in adaptation. But there's no reason to throw up our hands and say that mitigation is useless. Every bit of mitigation, of avoiding additional emissions, reduces needed adaptation down the line. And it's considerably cheaper to invest in mitigation now than that additional adaptation later.
Paxinterra wrote: "I have very little faith that we will even begin that process [adapting to climate change] until people are dying on a large scale from famine, drought and conflict."
The process of adapting to anthropogenic climate change began decades ago... people have been "dying on a large scale from famine, drought, and conflict" for thousands of years now. How many of the recent deaths from those (and other) causes are due to climate change is a matter of some debate, but certainly it has already been a factor.
When New York city finally put in better flooding control mechanisms after Hurricane Sandy... that was adapting to climate change. The flooding from the storm wouldn't have been nearly as bad if not for the sea level rise from climate change. Without that extensive flooding damage the city wouldn't have (and for decades hadn't) bothered to act. The same cycle can be seen all around the world. Humans adapt to their environment... it's automatic. We could do so better if we more often anticipated future changes and prepared for them in advance, but the idea that we haven't begun adapting to climate change is inaccurate.
As to your suggestion that we should not worry about reducing CO2 emissions because all of the tar sands oil and other fossil fuels will inevitably be burned eventually... if that is true then "there are going to be a lot fewer of us" no matter what attempts we make at adaptation. Burning all the known remaining 'easily accessible' oil and/or coal, let alone any further supplies made available by future technology and exploration would wipe out most of the human race. Fortunately, it seems fairly clear that fossil fuels are already on the way out... with no 'world economies collapsing' as a result.
Thanks Dana. That was an interesting exercise. Here are a few comments:
I only picked one point from Booker's article. He makes a load of arguments, most of which have been debunked many times before. The Paraguay one was new, interesting, and rather more complex than the rest.
We still don't know why there appear to be synchronized breaks across the Paraguay stations. Berkeley list station moves in 1971 for Puerto Casado and San Juan, but we don't have a documented reason for the rest. That's an interesting question for further research.
Trying to do this kind of work at the speed of the news cycle is hard. The video would be much better if we worked on it for a week. But it would be far less relevant.
One of the things we really hope to acheive with the MOOC is to equip anyone to be able to test claims like this for themselves.
When there are two rules for getting out of a hole that you have dug.
1) Do everything you can to get out of the hole.
2) Stop digging deeper.
If the oil sands and other alternate fossil fuels are all dug up it will be a disaster. We have to stop digging and take all measures to deal with the problem. Today, in the developed countries, adaptation is not too bad to deal with. We focus on stopping digging to prevent the problem from growing out of control.
I wish people would stop talking about how we need to do this and that to stop global warming. We have already done enough that global warming is a given. It will happen. If we stopped every emission today, we will still have a warming climate for the next 25 to 50 years. In that regard, it really doesn't make that much difference who or what caused it. What we need is to start thinking about how to cope with it. Shifting crops, drought, insect infestations, disease migration, lost animal habitat and extinctions, population migrations, weather pattern adaptation, and so on.
If we stopped trying to place blame and simply look at the trends, perhaps we could begin the process of adapting. Unfortunately, I have very little faith that we will even begin that process until people are dying on a large scale from famine, drought and conflict.
There is roughtly $15.7 trillion of sellable oil in central Canada's tar sands. If the XL pipeline is not built, then they will resort to trucks or trains. There is no way that the owners, investors and the government will agree to leave $15.7 trillion in the ground just because of the damage it will do to the atmosphere. Money is power and money has absolute control over the US government and msot of the Canadian government. Even if Saudia Arabia is successful in its current effort to undersell oil so that the tar sands are not profitable now, there will come a time in the future when it will be again and eventually they will sell all 178 billion bbls of tar sand oil. The money involved is so large that world economies would collapse if we suddenly stopped using oil.
So let's stop talking about who or why or reductions and get on with simple survival. If we don't, there are going to be a lot fewer of us to continue the arguing.
The full text of the additional paper from Berkeley Lab to which you refer can be found here.
This has caused some predictable responses from the ostrich brigade along the lines of "new study proves climate models are crap, blah, blah, blah". What does not seem to have penetrated various skulls is that this paper basically suggests that Arctic Amplification could be even worse than otherwise expected.
The Berkeley paper strongly suggests that emissivity values used in radiative transfer calculations may be incorrect under certain conditions - e.g. at high latitudes and/or altitudes, and low water vapour content. In particular, this would seem to be of importance when linked to the presence or absence of sea ice.
Surface properties apparently can greatly affect emissivity in certain spectral regions. The paper states that, in the far infrared region of the spectrum, a frozen surface can radiate more effectively than open water. So, when sea ice disappears, the amount of far infrared lost to space would appear to be less than previously expected.
The Ice/Albedo Effect is a well known example of a positive feedback mechanism. Less well known perhaps, is the fact that it also has a built-in negative feedback: temperatures over open water do not plummet the way they can over ice, and this in turn allows easier transfer of heat energy from the ocean into the atmosphere which, in turn, is lost to space. (There is a very strong analogy with ENSO: when el Nino conditions prevail, although this leads to a surface warming, it also enables heat energy to escape from the ocean into space.) If this negative feedback is diminished, then the overall heating effect is enhanced.
(NB The authors actually characterise this as a positive feedback, rather than as a reduced negative feedback as I described it. To be honest, I can't be bothered arguing semantics.)
If the Berkeley paper stands the test of time, we could quickly see a deleterious effect on Arctic winter sea ice area/extent, which will inevitably feed back into summer values. Once we start regularly getting significantly reduced sea ice levels by mid May (or thereabouts) then it's game over for the September minimum.
With truly delecious irony - that is obviously lost on some - Berkeley use a climate model to do the donkey work for this paper.
This is the top of atmosphere energy imbalance data sheet I came up with.
by the way, another paper published about the same time as the Caldeira paper above showed that the far-infrared response of sea ice is vastly different than that of open ocean. This calculus was not included in the Caldeira & Cvijanovic modelling.
I guestimate we will settle at about 4 meters for the first century of this challenge. Just for reference I roughly calculated what 1% of insolation retention would do to the cryosphere, if all that additional heat went there. I was guessing centuries, or millennia for 20 meters of sea level rise. If my back of the envelope is right, its only about 14 years of such retention rate. What is the maximum that increased CO2 and methane and other GWG can cause? We don't know. Fortunately, just like Pluvinergy can resolve our energy issues, Pluvicopia, not published becasue of patent processes, can resolve 20 meters of sea level rise in 500 years. These technologies are geoengineering of the good sort, but it is totaly upon us to decide what this means. If we convert the deserts into gardens, what kind of moral statement is that making? Etc.
sgbotsford, good argument on logical response, although I do feel terrified when I consider the implication of the coming changes for my kids and grandkids. When 40% of civilization's infrastructure is threatened or destroyed, and when reconstruction will worsen the case, it will be terrifying. In net, it may be good for Canadians, but for the rest of the world it is bad. Terrifying is appropriate if one can see beyond one's little life, which this problem requires.
In your first point, you correctly state that total loss of sea ice in the Antarctic is not going to be happening any time soon. (Centuries? Millenia?)
However, jja#38 did actually write...
"FYI Caldeira & Cvijanovic (2014) showed that the removal of all sea ice produced a global forcing factor of 3 watts per meter squared. If we attain an ice free condition by June 1st we will experience a significant portion of this forcing."
Although not explicitly stated as such, the reference to June 1st (my underlining) makes it implicit that the Northern Hemisphere is being discussed. (There being not much of an Ice/Albedo effect in the SH that close to the boreal summer solstice.) :)
As regards your second remark, whilst it is certainly in no way contentious, I don't know where it is being directed. I did a "Find on Page" for "1000" and for "much", but I couldn't find what you were referring to.
(On the other, as my wife never tires of reminding me, I did once fail to find a pair of tracksuit bottoms in an otherwise empty sports bag!)
william @8, in addition to Tom's comments about rate of change, it should be noted that "a new ice age" due to low atmospheric CO2 levels is off the table unless we develop some technology which rapidly decreases the CO2 content of the atmosphere and then use it to excess. Take a look at natural CO2 shifts over the past few million years;
Repeatedly, CO2 spikes up ~100 ppm over the course of 10 to 20 thousand years and then slowly declines back down ~100 ppm over a period of 90 thousand years or so. We've taken the atmospheric CO2 level from ~280 ppm to ~400 ppm over the course of the last 150 years or so. That 120 ppm increase, let alone however much further we drive it up before we get emissions under control, will take tens of thousands of years to reverse naturally. If we could somehow stop fossil fuel emissions today we'd be getting back to ~280 ppm right around the time the next 'interglacial' warming period / CO2 increase was set to start.
Human technology and society today is radically different from that of a thousand years ago. What human technology and society will be like more than 100,000 years in the future is inconceivable. Ergo, we can pretty much ignore the idea of 'the next ice age' (i.e. glaciation). If it ever happens it will be in a world so different from our own that we would have no basis on which to plan contingencies.
Regarding "removal of all sea ice" (38/jja), isn't that unlikely (for a while) in the Southern Hemisphere because of the supply of more easily frozen fresh water from the Antarctic glaciers? The ice itself could be a factor as glaciers thin and slide into the ocean.
And as far as the 1 part in 1000, "that's not much, is it?", if the average depth of the oceans were increased by .1%, sea levels would be 12 feet higher.
MEJ, a new resource on the Paraguay data is now available. It really makes Booker (who it directly addresses), and by extension Homewood, look like fools. The video is by SkS's Kevin Cowtan (another expert on global tempertues, but one I rarely disagree with in other areas).