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Comments 1 to 50:

  1. The Most Terrifying Papers I Read Last Year

    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. 

  2. The Most Terrifying Papers I Read Last Year

    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.

  3. The oceans are warming so fast, they keep breaking scientists' charts

    dr2chase #42

    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!)

    Cheers    Bill F

  4. Just when did humans first start affecting the climate?

    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;

    CO2 & Temperature

    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.

  5. The oceans are warming so fast, they keep breaking scientists' charts

    Two remarks --

    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.

  6. Temp record is unreliable

    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).  

    (H/t to Victor Venema)

  7. The oceans are warming so fast, they keep breaking scientists' charts

    One Planet Only Forever @39,

    Most of that is fine; perhaps the description is a little awkward in places. The CO2 emissions from land use (mainly chopping down and burning trees) was the largest source of CO2 emissions until after 1900 and wasn't until the 1970s that fossil fuel emissions can begin to be described as "dominant."

    The long term proportion of our emissions of CO2 in the atmosphere will drop to about 20% (or more if we emit way past 1,000GtC) as the oceans will continue to absorb with deep water cycling to the surface and that 20%+ level is reached in about 1000 years. Archer et al (2009)  (PDF here) is the standard reference.

    While the sun does emit infra-red, there is almost no overlap between the incoming & outgoing radiation spectra. So it would be confusing mentioning the solar infra-red which may infer there is an overlap. Insolation is higher frequency that out going which is all low-frequency infra-red.

    And the resulting ΔOHC from a warmed climate won't see deep temperatures rising the same amount as surface temperatures. You have to ask yourself why the oceans are so cold. The surface is warm (on average) and the rocks below are molten if you go deep enough. So why are the oceans so cold? The answer is the cold salty waters from the poles is the densest water on the planet and that sinks into the ocean depths where it is well insulated from the surface and the Earth's core. Until the poles are free from ice, the very deep ocean will remain roughly at the temperature of freezing salt water.

    The actual path of global temperature when CO2 emissions stop will depend on how quickly the emissions are ended. And remember there are other GHGs being emitted.
     The IPCC RPC2.6 shows one such pathway with climatic forcing peaking by 2040. Models show the resulting temperatures remain flat to 2100 although there is a drop in succeeding centuries as this graphic from Meehl et al (2012) shows.

    meehl et al (2012)

  8. Temp record is unreliable

    Thanks 'RH' I will shorten the links next time (A noob mistake)

    Thanks so much scaddenp, Rob and Tom. Tonnes of info there for me to study up on. You have me going in the right direction now. Like most folk I don't have the depth of knowledge many of you people do so it is pretty easy for a seasoned campainer like Homeswood to 'punk' me.

    So glad I have SkS as backup.

  9. Temp record is unreliable

    MEJ @332, in addition to my prior comment, ATTP shows the BEST unadjusted record for Puerto Casado, with dubious data noted, and break points shown:

    You will note that the break points coincide with known station moves.  As they are known station moves, Homewood is arguing without evidence that those station moves had no effect on the temperature, whereas comparing the station temperature record with the regional average clearly shows that there were effects (as we would expect).

    We can also see the break point adjusted data:

    Steve Mosher, one of the BEST team comments:

    "The first step we take is to find all those stations that are duplicates. And the duplicate test involves fuzzy logic. So you look at the locations and see how close they are, you look at the name and see how close they are.. and then we look at the first differences in data to see. how close they are.

    There is second pass that looks for data similarily first, cause sometimes you get stations that have exactly the same data, but due to metadata issue the metadata is way wrong. These are really rare. I can’t recall one off the top of my head.

    This particular record has multiple sources and multiple locations that differ very slightly.  When the location differs we ‘slice’ the record. In other words the record is NOT adjusted for a station move, rather its computed as three different stations.

    Slicing has ZERO effect if there was in fact
    A) no real station move
    B) a station move that doesnt result in a change in temp

    That is something most people dont get. That is, if you “over slice” or split a record that should not be split the effect is zero. In this case we have three difference locations given for a station with the same name. So we treat it (mathematically) as if it is three different stations. If there was a move and the move had an effect on temperature, then splitting the record will allow us to fit the final surface treating those segments as independent. Again, if the metadata was wrong and there was no move or a move that didnt effect things, then there is no adjustment to make."

    Richard Betts also comments:

    "Actually one of the largest adjustments is the ‘bucket correction’, which aims to remove a systematic cold bias earlier in the SST record which arose from sea temperatures being measured in buckets hauled up to the deck, rather than at engine intakes as more recent measurements are. The bucket correction reduces the apparent warming over the 20th Century – it’s very well-known, but Mr Booker seems to have either not heard of it, or somehow forgot to mention it….!"

    (As fair notice, I disagree with Betts and Mosher on a number of topics.  On the area of temperature records, however, they are undoubted experts and I would not disagree with them on that record unless I was aware of other similar experts with whom I not only agreed, but agreed for the same reasons those experts give for their views.  Recognition of their expertise does not, however, mean I agree that they are right, or even sensible in some cases, in other topics outside of that expertise.)

  10. Temp record is unreliable

    MEJ @332:

    1)  You cannot have been shown to be a total fraud unless it has been shown that you have knowingly used false information yourself.  It may (though very doubtfully) have been shown that you also are decieved, which is an entirely different matter.  

    2)   Paul Homewood is definitely pulling a swifty when he compares with NCDC data.  The reason is that the NCDC uses a 5ox5o grid, equivalent to 555 x 555 km at the equator.  That is a much lower resolution than NASA GISS's 250 x 250 km grid shown at the same location as the normal 1200 km radius he shows above.

    Here is the NASA 250 km grid equivalent to the graph he shows:

    And here is the GISS map and NCDC map side by side, for northern South America:

    Note that for the GISS 250 km grid, every gridpoint over land has at least one temperature station in its bounds.  Yet clearly the GISS 250 km grid covers much more of northern South America than does the equivalent lower resolution, NCDC map.  It follows that GISS uses more temperature stations in South America than does the NCDC, and that using the NCDC map entirely misrepresents the basis of the GISS data.

    This may be partially just ignorance from Homewood.  It is well known that NCDC uses only the GHCN for land only data, while GISS also uses the GHCN.  GISS, however, uses additional stations to those found in the GHCN (something not commonly known, but which should be known by anybody commenting on global temperatures).  However, given the existence of the GISS 250 km product, it should have been used regardless, if only so that readers knew that this was information GISS presented publicly, on a website, as easily accessible as the 1200 km version.  Homewood creates an impression that this is something GISS does not want us to know, whereas it is something they actively publish.

    2)  The use of the 1200 km version is based on known properties of temperature anomaly change over distance.  This information was published in peer reviewed papers, as was the method whereby GISS uses it in constructing their temperature data.  If Homewood wanted to make an honest critique, he would have cited those papers and stated his objections to the reasoning therein.  That he does not leaves the impression he has not even thought about the topic, let alone considered the relevant empirical data.  Indeed, as a mater of scientific reasoning, as he does not discuss, that must be our presumption.  So, we have from GISS cogent, evidence based reasons for their methods - and from Homewood, an argument from personal incredulity, and nothing else.

    3)  The reasons for, and method of adjustment of temperatures are also heavilly discusses in the scientific literature, and based on detailed examination of evidence, including direct comparison between temperature readings for different thermometer types, thermometers at different altitudes etc.  Again, in response to that literature, Homewood argues by, first, ignoring it so that he readers do not know that there is an objective basis for the adjustments; and second presenting an argument from personal incredulity and nothing else.

    As it happens, I have seen similar arguments presented regarding data from New Zealand and Australian stations.  These arguments have been much better presented, actually relying on more than personal incredulity.  On examination, however, in every case that I have examined, they have been wrong.  In most cases it has been trivial to show that they are wrong.

    I do not have the ready access to the relevant data in South America that I have in Australia and New Zealand, so I will not repeat the excercise.  I know from that prior experience, however, that Homewood's argument from personal incredulity is almost certainly wrong.  I will go one step further than that.  The Berkeley Earth project (BEST) uses an even larger data base than GISS, an entirely different method and does not adjust the raw data.  Rather, where there is a clear break in the temperature record for a particular station, they treat it as a separate station and let things fall were they will.  That method is well justified in that "stations" are often composites of records from differnt instruments, locations and site conditions which vary over time.  In one case from NZ, the site moved to several different places in the city, from buildings to garden settings, with changes in altitude in 10s (and in one case I remember which may not be the same city, 100s of meters), and in one mover from an east facing coast (with typically warm offshore waters) to a west facing coast (with typically cool offshore waters).  Every such move would have changed the temperatures read, and treating it all as just one continuous record without adjustment would be a farce.

    In any event, here is BEST's temperature record for Paraguay:


    So, overall Homewood makes his case, for the most part, by simply not addressing the relevant evidence.  Indeed, some of the crucial evidence he keeps carefully out of sight.  As is standard for "skeptics", he is very careful to make his arguments to the uninformed who will not be able to pick up the flaws in the argument, rather than submitting it to peer review by experts who will be able to pick out those flaws.  I think, in so doing, he fairly judges the quality of his argument.

  11. Temp record is unreliable

    Oh! I see. He's also comparing a GISS image to a NOAA image.

    Talk about apples and oranges all around.

  12. Temp record is unreliable

    MEJ...  I can already pick out a big mistake that Homewood makes in his first two figures. Top figure is relative to 1951-1980. Second one (of his creation through the GISS site) is relative to 1981-2010.

    Why would he use different base periods? We have two choices. 1) Stupidity, and 2) Deceipt.

    I decided to try to check which.

    When you go to the data page at the GISS website where you generate these maps you get a lot of clues. First, the default base period presented in 1951-1980. You have to change it to get a different base period.

    When you switch it back to the 1951-1980 base period you get this:

    But even when we select his exact parameters, we still don't get the same image he presents. So, I don't know where he's getting that figure.

  13. Temp record is unreliable

    Thanks 'Rob P' I have poured over these graphs to see where he has manipulated the data but with my limited understanding I just need a Scientific person to go through it for me and explain it. A couple of things make me suspicious No link on the NOAA/NCDC Global Map showing 'no data' areas and his raw data graph has a diferent ID code 30886086000(4) and he is showing graphed Temperature rather than Anomaly and comparing the two?

  14. Temp record is unreliable

    Hi scaddenp Booker in The Telegraph is simply quoting Homewood's article on his 'notallpeopleknowthat' website as are all the usual suspects. Skeptics don't see it as junk at all. To them Homewood is the actual truth and his graphs demonstrate to them how all the Science is just fabricated rubbish. You can sit back and laugh but the Scientific community will lose the debate. Thanks for that link I just couldn't find ANY redress on the issue. If you Google to try and get a Scientific view the denialists have that absolutely locked up page after page. Science simply doesn't get a look in.

  15. Temp record is unreliable

    MEJ - see the post about this at ATTP and note also the comments there by Victor Venema. This is just echoing junk from Booker in the Telegraph. In short, laughable nonsense from the usual sources. And just as an aside, suppose temperature record really was junk - what then the explanation for the change in the long term integrators of climate change - sealevel and glacial mass?

  16. Temp record is unreliable

    Paul Homewood from 'notallpeopleknowthat' successfully? undermines the reliability of Temperature records.

    "Massive Tampering with Temperature Records in South America"


    He starts off with GISS Global Temperature Anomaly:

    GISS Temperature anomaly showing Global Warming



    Then proceeds to show where gaps (grey areas) in the data are totally missing using NOAA /NCDC Map:

    NOAA/NCDC Showing areas where no data is available

    (Strangely he doesn't provide a Link to this Map)

    So he has shown that the GISS Global Temperature Map is derived from data that simply does not exist.

    He then goes on to hammer home his point of temperature data being falsified by highlighting three NOAA weather stations in Paraguay. I will just do the one at Puerto Casado.

    Here is GISS graph for Temperatures taken from Puerto Casado:

    GISS Temperature graph for Puerto Casado weather station

    All good temperatures seem to be rising as expected in Global warming Earth.

    THEN he states he takes the Raw Data and without ANY manipulation of the data produces a graph from that data:

    Homewood graph from GISS raw data

    There you go, without 'adjusting' the data it actually shows COOLING not warming.

    He then goes on to present NOAA/NCDC GHCNM modelling for Peurto Casado weather station where the Quality Controlled Unadjusted Data shows COOLING and the Quality Controlled Adjusted Data shows warming.

    NCDC Unadjusted data showing cooling/adjusted data showing warming

    He does the same for two other Paraguayan weather stations, Mariscal and San Juan.

    So it is easy for Homewood to make the statement "Scientists just adjust the Temperatures to match their Global Warming agenda" Once again it is all just Scientific rubbish when you look at the 'real' data it clearly shows cooling not warming. Why do they 'adjust' the data? To ensure all the Modelling shows Global Warming not as it really is Global Cooling. For most of their so called 'modelling' they don't even have data!!!! It is just a 'best guess' scenario.

    This has gone absolutely 'viral' with all Climate Denialist websites, bloggs and Newspapers quoting Paul Homewoods 'authoritative' study.

    Responce from the Scientific community. So far none that I can find.

    As a supporter of Global Warming / Climate Change I am hammered mercilessly and shown to be a total fraud.

    Moderator Response:

    [Rob P] - Yes, just the latest example of cherry picking and conspiracy ideation from climate science contrarians. SkS will have a response soon enough.

    [RH] Shortened links.

  17. Models are unreliable

    Tom Dayton @788 correctly notes that "temperture" is a theoretical construct - one that has proved invaluable in uniting a whole host of observations.  I will merely note that given that our sense are sound, visions, smell, taste and touch, even such objects as the sun, or even other people (given our lack of ESP) are theoretical constructs for us.  We just do not notice because they are so good at uniting disparate phenomenon, and we are so used to them in practise, that unless we are of a philosophical bent, we don't think about it.  

  18. Models are unreliable

    Adding to Tom Dayton's excellent post @788, I want to note that a theory is of no practical use in science if it does not lead to mathematical predictions.  Absent such mathematical predictions, comparison to observations can only be vague at best.  And the way that theories lead to mathematical predictions is by being couched in mathematical models.  Consequently, absent mathematical models, a theory can only give vague, qualitative predictions that constitute hand waving more than science.  It is one of the outstanding features of climate science that they have taken such extensive efforts to couch their theories in mathematical models, and to check those models against observations across a wide range of observations (not just Global Mean Surface Temperature).  Given the difficulties in so doing, both due to the complexity and chaotic nature of climate - it is a stirling effort.

    Climate scientists are often criticized for making model based predictions.  As the model is just the theory couched in the most mathematically precise way we are capable of at the moment (due to budgetary constraints and limitations of computer power), what else can you base your predictions on?  By definition of "prediction", you cannot base it on observations because the observations go outside the current observations.

    In fact, those who say we should not base predictions on models typically resort to predictions made on crude models that lack physics, and are constrained to just one or two climate variables.  In effect, they want climate science to remain at the hand waving stage found around 11 pm in any bar room across the world.

    This is not to say that models are perfect.  They are not, and some of their imperfections may be due to flaws in the theory they embody.  (Others are related to innacccurate initial or boundary conditions, and/or limitations of computational power.)  But you can only find the flaws in the theory by putting them in mathematical form and comparing them to observations (ie, by using models), so that is no reason for not using models.  And it is reasonable to make our predictions based on the currently best available theory.  The complete lack of climate models developed by "skeptics" means by default that must be the conventional theory accepted by the IPCC.

  19. Roy Spencer finds negative feedback

    Tom Dayton, I want to aplaud your excelent series of responses to Deon.  In particular I liked your response regarding the theory/observation split in science (which many people do not understand).  Deon, read carefully and learn.

  20. It's not us

    dvaytw @89, first Phil's response is correct, and needs no further addition unless you want to get into the minutia of insolation at particular latitudes at particular times of day.

    Second, Bob Loblaw's resonse is also correct, but may confuse at first blush given that insolation is normally calculated at given points using the zenith angle and latitude, such that at noon on the equator on the equinox (and thus ignoring seasons), the angle used is 0 degrees, and consequently the cosine rather than the sine is used:

    The formula for declination, to partly take seasons into account is:

    δ =23.45*cos(2*π*(JD-172)/365)

    To fully take seasons into account, you also need to take into accoun the variations in the Sun/Earth distance.  A partial formula for that, plus additional details can be found here.

    In the end, daily insolation at the top of the atmosphere, ploted for latitude and time of year looks like this:

    The very high summer insolation at the poles surprises most people at first glance, but is due to having 24 hours rather than a mere 12 hours insolation.

    Needless to say, this is too much information for most uses, and we can resort back to the annual average figure as calculated by Phil.  Needless to say, however, climate models integrate everything based on their smallest time step (typically one to three hours, I believe).  I mention that because I have seen a number of "skeptical" arguments based on assuming that climate models use the same simplifying assumptions used in simplified explanation (as if they use no physics more complex than taught in grade six).

  21. Roy Spencer finds negative feedback

    Deon wrote:

    4) I have a number of questions regarding climate modeling:
    a. How is “human activity” operationalized? In research, concepts have to be measurable. Data has to be obtained. That data must be accurate, valid, and reliable. It would appear that in Climate Science that this concept is largely imputed.

    Deon, the "human activity" that is the most important cause of anthropogenic global warming and the attendant other climate changes is increase in greenhouse gas emissions into the atmosphere and to a lesser degree reduction of natural greenhouse gas removal from the atmosphere.  I am flabbergasted that you lack such fundamental knowledge yet are strident in your criticisms of the science, and implicitly, the scientists.  You really need to stop criticizing until you've learned the basics.  Start here at Skeptical Science with The Big Picture.  Then to learn how that knowledge was built, read The History of Climate Science.  Because you seem untrusting, you should then follow up by reading more details of the history in Spencer Weart's The Discovery of Global Warming.  After all that, if you have some specific questions please post them here on Skeptical Science but on the appropriate thread.

    Deon wrote:

    b. What dataset used in Climate Science dates back more than 100 years (do recall the long term cycle of 100,000 years) and:
    i. Is continuous,
    ii. Measured consistently (across the globe, using the same methodology), and
    iii. Applied without extrapolation.

    Deon, there is a huge amount of data from a huge number of sources collected by a huge number of people over a huge number of years.  Your criteria that you are presenting as absolute of course have not been met, but they are not met in any scientific field--not any.  Period.  Obviously you are not a working scientist in any field, because your misunderstanding of science is profound.

    Deon wrote:

    5) As a suggestion this question may be relevant: if there is a natural long term trend, what impact does human behavior have on raising global temperature above the natural trend? Please explain to me how you will answer this question. Even propose an alternative to it if you must.

    Deon, the natural forcings have been teased out from the human forcings.  One place to see a summary of that evidence is the Advanced tabbed pane in the post "It's Not Us."  Just one example of detail is that the Sun's input to Earth has been stable (or even decreasing slightly) since at least 1960.

    Please do ask questions here at Skeptical Science.  But do so on the appropriate threads.  If you're unable to find an appropriate thread despite making a sincere attempt to use the list of Arguments and the Search field (which is at the top left of every page), then comment on the most recent Weekly News Roundup.

  22. It's not us


    To completely muddle Phil's explanation, you need to keep in mind that the sun's rays (at the mean earth-sun distance) are measured at a right angle to the parallel beams. When those rays fall on a surface that is not at a right angle, the intensity is reduced. The mathematics of this is straightforward - the intensity is reduced by sin(angle) [when an angle of 90 is used for the case where the sun's rays are at a right angle to the surface, and 0 for the surface being parallel to the sun's rays].

    To get a 24-hr total for the entire earth, you could then calculate the intensity for each point on the surface (including the dark side) for every time of day - accounting for the sun angle and its effect in intensity-  and then integrate (sum) over the entire globe and day.

    And then, after doing all that, you'd realize that the ratio is 4, and it would dawn on you that the size of the shadow cast by the earth is pi*r^2 and it doesn't matter whether the earth is a disk, or a sphere, or a cone, or any other shape. The size of the shadow tells you how much sunlight it intercepted. For emissions, the shape of the earth does matter, and a sphere is a close approximation.

    It's sort of like the joke about the mathematician, who was asked to solve the following:

    Two trains are 120km apart, travelling towards each other at 60km an hour. A really fast bird travelling at 120 km/hr takes off from one and flies to the other, then instantaneously turns around and flies back, repeating until the two trains meet. When the trains meet, how far has the bird travelled?

    The mathematician quickly says "120 km". The fellow posing the questions says"

    "That's right. You know, a lot of mathematicians try to answer that by solving for each successive the time and place that the bird reaches a train and turns around, and then integrating the infinite series over time to get the total. I see you took the fast solution."

    The mathematician says:

    "There is a faster way?"

    [The trains travel for one hour until they meet. The bird travels 120 km in one hour.]

  23. The oceans are warming so fast, they keep breaking scientists' charts

    jja #38:
    Good point!
    If the warming of SH oceans between 1970 and 2004 (pre Argo) has been underestimated, it would surely produce a too low estimate of the energy imbalance for that period. On the other hand, if the warming – and therefore energy imbalance – was faster before 2004 (as Durack et al 2014 implies), the energy imbalance cannot have grown that much in recent years unless the warming in the Argo era (2005 -->) has also been underestimated.
    That doesn’t mean that future energy imbalance will not increase above the current level. Accelerated CO2 emissions, mitigation of Asian sulphates and positive feedbacks from albedo changes and the carbon cycle may well speed up the warming of both the surface and the oceans.

    It’s worth noting that the energy imbalance doesn’t depend on the net forcing itself, but how fast that forcing has changed recently. If the net forcing stabilized at the present level tomorrow (unfortunately not very likely!), the energy imbalance would decrease over time and approach zero as the warming Earth emitted more IR to space and closed the gap between incoming and outgoing energy, and the temperature would stabilize at a higher level.

  24. The Most Terrifying Papers I Read Last Year

    OK, now I'm scared again.

    Climate variation explains a third of global crop yield variability

  25. The Most Terrifying Papers I Read Last Year

    'Concerned' is justified, 'terrified' is not.  These ice shelves should give us plenty of time to move out of the house before it is inundated.  The terror comes later when you realize your neighbors have a limited capacity for compassion.

  26. One Planet Only Forever at 05:25 AM on 26 January 2015
    The oceans are warming so fast, they keep breaking scientists' charts

    MA Rodger@20 and Tom Curtis@21,

    Thank you for the explanations. They help clarify things for me. I have only fully read the IPCC summary for policy makers and parts of the more recent report regarding the impacts. I have tried to understand the more detailed supporting parts of the IPCC reports but do not find them to be easy to turn into a basic understanding of what is going on. I find the people on this site, and those presenting information on sites pointed to from this one, help me get a clearer basic understanding of what is going on (though I admit that much of what is presented here can still be tough for me to follow or grasp the basics of).

    I have been thinking more about this ocean heat content (energy content), and realize that for the basics related to it to make sense to me I need to think about what happens in a balanced energy case before human forced changes of CO2 in the atmosphere, then consider what happens when CO2 concentrations in the atmosphere are increased by human activity leading to the transition to a new balanced energy state.

    I would like to know if the following is reasonably correct:

    My basic understanding of the balanced energy case for our planet, no human impacts affecting CO2 in the atmosphere.

    • Many randomly occurring or cyclical things would make the total heat content of the oceans vary but the averages of long periods of data, like 30 year averages, would be fairly constant. There would be no long term trend up or down.
    • A temporary condition like El Nino would cause heat content to leave the oceans because the warm surface emits more infra-red up through the atmosphere and also warms surface air by contact with the warm water surface. This would temporarily result in a higher global average surface temperature and more energy leaving the planet's system than is coming in.
    • A temporary condition like La Nina would cause heat content to be added the oceans because the cooler surface emits less infra-red up through the atmosphere and also takes in heat from the surface air that comes in contact with the cooler water surface. This would temporarily result in a lower global average surface temperature and less energy leaving the planet's system than is coming in.

    The result of human activity that produces excess CO2 in the atmosphere.

    • Burning buried hydrocarbons produces extra CO2 in the atmosphere which is a change from a balanced state . Other human activity that affects the atmospheric CO2 concentration includes reducing the amount of organic growth occurring on the planet or changing the type of organic growth. But the burning of fossil fuels is by far the dominant human impact.
    • In the short term the approximate response of the global carbon cycle would be to have 45% of the extra CO2 remain in the atmosphere, 30% of the extra CO2 would be taken in by the oceans, and 25% would be absorbed into added growth of existing organics. (Question here: Is the 30% taken into the oceans including CO2 captured in fertilization of ocean based organic matter?)
    • In the long term more atmospheric CO2 would go into the oceans. But the long term balanced case would still be a new higher CO2 atmospheric concentration than before the human impact.

    The way the changes resulting from human impact affect ocean energy content.

    • Increased CO2 in the atmosphere means that less incoming solar energy will leave the planet. The result is more energy being kept in the planet's environment in a new balanced energy case.
    • The new balanced case will have a higher average surface temperature, because the higher surface temperature is the result of it being more difficult for energy to be emitted through the increased amount of atmospheric CO2 (CO2 absorbs infra-red. Very little incoming radiation is infra-red, a large amount of surface emitted radiation is infra-red).
    • The requirement to have a higher surface temperature for the new energy balance case also means that the ocean energy content will increase since the surface will be warmer. The new balanced condition of ocean energy content with the warmer surface means that during the transition to the new balanced case all ocean surface conditions from La Nina through to El Nino will on average be gathering more energy into the oceans, with the rate of energy gain by the oceans being highest when the initial extra CO2 atmospheric concentration occurs, and reducing as the ocean becomes warmer.

    I am still curious about the long term balanced case for ocean total energy as a result of increased atmospheric CO2. Is it correct to say that ultimately the oceans would be expected to warm through their entire depth by an amount similar to the expected increase of surface temperature (maintaining the relative temperatures with depth - not warming to one uniform temperature), or would the warming only need to be to a condition that has the near surface waters warmer by the same amount that the global average surface temperature is to rise by?

    I understand that in the long term, after human activity stops producing excess CO2, some of the 45% of produced excess CO2 that stays in the atmosphere in the short term will be absorbed into the oceans. So there would be parallel changes happening. In the long term, the oceans would be accumulating more energy while at the same time the atmospheric CO2 concentrations would be reducing. Is it expected that after human impacts increasing CO2 are stopped the rates of ocean warming and reduction of CO2 concentrations would result in the oceans just eventually warming to be balanced with the lower long term new balanced CO2 atmospheric concentration? Or will the oceans warm a little above that level before CO2 concentrations have fully declined to the long term balanced case? This has little to do with the need to rapidly reduce the human CO2 impacts. It is more a matter of curiosity.

  27. The oceans are warming so fast, they keep breaking scientists' charts

    HK @37

    Do you realize that Hansen and Sato relied on southern hemisphere OHC values that were underestimated by up to 50% as shown by Durack et. al. (2014) (so was Nuccitelli et. al (2012).

    Yes, I recognize that there is the possiblity of severe increases in asian sulfate emissions or another stratospheric volcanic eruption (the ones that produced your dips in the Hansen graphic). 

    Those events do not matter.  Also, there is the distinct possibility that we will engage in statospheric geoengineering sometime in the next 10 years, that will also severely affect TOA.

    However, the trend that I shared is consistent with the TOA values over a 35 year trend.  With future albedo changes in the arctic and tropical forests, as well as the potential for reductions in Chinese sulfate emissions, the TOA trend is a severe underestimation of future anthropogenic forcing (with feedbacks)  As we will very soon discover.

    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.  I expect this to occur sometime in the next 25 years (absent of geoengineering).

  28. Roy Spencer finds negative feedback

    Deon wrote:

    CO2 and temperature trend not directionally consistent:

    See "CO2 Lags Temperature--What Does It Mean?"  Put comments on that topic on that thread, not this one.  Off-topic comments on this thread will be deleted.

    Deon wrote:

    Shorter cycles have an impact:

    See "It's a 1,500 Year Cycle."  Put comments on that topic on that thread, not this one.

    Deon wrote:

    3) The dominant opinion in Climate Science appears to ignore the above, or to acknowledge this with qualification. The most worrying element in this is the propaganda: human activities are causing climate change. Causality. If, at this moment you are not slightly uncomfortable, you might be practicing in the wrong field. [At the same time the statement can be so ambiguous as to allow the bigot to claim correlation.]

    See "It's Not Us."  And comment there, not here.

    I don't have time to answer Deon's #4 and #5 right now.  If nobody else has done so after a few hours, I will.


  29. Roy Spencer finds negative feedback

    Deon wrote:

    2) Geology as an empirical Science has demonstrated a long term trend in global climate. On average, every 100,000 years temperature peaks accompanied with a high in CO2 levels. Yet, the relationship is not consistent, nor does it explain the effect of shorter cycles - more precisly our current placement within all the cycles: long, medium, and short.

    Milankovitch in brief:

    Deon, climatologists are well aware of Milankovitch cycles.  Indeed, there is an excellent post here on Skeptical Science about them.  For more details including math, see Tamino's "Wobbles, Part 1," then "Wobbles, Part 2."  Then Tamino's "Milankovitch Cycles" that mentions that currently and for the past really long time Milankovitch Cycles have been cooling, not warming, the Earth.  For that last point, details are in the Hansen and Sato paper "Paleoclimate Implications for Human-Made Climate Change." If you want to discuss orbital cycles more, do so on the Skeptical Science post "Milankovitch Cycles," not on this thread.  Off-topic comments on this thread will be deleted.

  30. Roy Spencer finds negative feedback

    Deon, I have responded to your assertion #1 on the post that is the counterargument to the myth "Models are Unreliable."  If you want to comment further on that topic, do so on that thread, not this one.  That topic is off-topic for this thread you are reading now.

  31. Models are unreliable

    Deon van Zyl commented on another thread:

    Climate modeling is a political issue. No, it is not a Scientific issue, because it is not Scientific. Science relies upon direct observation – not extrapolation. Empiricism underpins Science. Modeling is an aid to Science. Theory is not Science. At best a theory is a guess at the consistency of Reality. Climate modeling is an exercise in Mathematics. Models are based on assumptions. Assumptions prove nothing.

    Deon, in fact science is just as much extrapolation via theory into models, as it is observation.  In fact, "direct observation" is only the first step.  For example, you probably think that looking at a mercury column thermometer and noting the number that the column reaches is "direct observation" of temperature.  But it's not.  Instead your temperature observation relies on your model of the relationship of the mercury's height to the temperature.  The very notion of temperature is theoretical.  When an apple comes loose from a tree and you predict that it will fall to the ground, you are using a model.  All those models are based on observations.  All theory is generalized observation.  Models are instantiations of theories.

    Perhaps you think climate models are poor models because you think they are merely statistical models that assume the future will be the same as the past.  But that is incorrect.  Climate models are models of physical processes, whose elements are constructed to match empirical observations of fundamental physical phenomena such as how much water vapor air can hold at a given temperature.  The models are then run so that all those individual elements interact, yielding the climate projections.

    To learn about how climate models are built and run, click the links in the "Further Reading" green box below the original post on this page (right before the comments section).

  32. It's the sun

    HK also commented on energy imbalance, with material that might be used in the new section I requested be added to "It's the Sun."

  33. The oceans are warming so fast, they keep breaking scientists' charts

    jja #32:
    The graph in your link gives the impression that the top of atmosphere energy imbalance has risen and will continue to rise more or less linearly, but that is not the case.
    This graph from James Hansen’s Earth’s energy imbalance and implications shows several estimates of how the energy imbalance changed from 1980 to 2007.

    TOA energy imbalance

    As you see, there have been large ups and downs, but the overall trend seems to be positive. Interestingly, the energy balance was negative after the Pinatubo eruption in 1991 and possibly also after El Chichón in 1982.

    If I should try to estimate the energy imbalance for the last 5 years (2009-2014), it would be something like this:
    Change in OHC upper 2000 meters: +6.68 x 1022 J (Source)

    Assuming non-ocean components make up 5% of the total and ignoring OHC deeper than 2000 meters, which is very uncertain, gives this change of global heat content:
    6.68 x 1022 J / 0.95 = 7.03 x 1022 J
    Dividing this by the number of seconds in 5 years and square meters of the Earth’s surface gives an average energy imbalance of +0.87 W/m2.
    So the rate of warming seems to have increased since Hansen’s estimate of +0.58 W/m2 between 2005 and 2010, however I admit that the numbers in my calculation are far from certain.

  34. PhilippeChantreau at 00:26 AM on 26 January 2015
    Roy Spencer finds negative feedback

    Deon you make broad statements that indicate only your lack of true familiarity with the body of knowledge you pretend to criticize. There is plenty of information available here and links to NASA, NOAA and yoher sites, where an abundance of data is available. Assessment reports of the IPCC are also recommended reading.

  35. Roy Spencer finds negative feedback

    Deon, I hope you'll continue to engage, but on the appropriate threads.  The answers you seek are on this site, all linked to the published science.  Use the search feature.  I could make a series of links to the appropriate threads, but you've galloped so wide and far that I'd basically have to link the entire site.

  36. Roy Spencer finds negative feedback

    I have read the comments posted here and have a few of my own to make.

    1) There is a great desire to discredit Spencer as a junk scientist. Allow me to advance the following argument. Even though the elitism of Science and its direct disconnect from the majority of the people on this planet has resulted in a large number of geniuses playing with mathematical models largely irrelevant to daily existence, the impact of guesswork is not minute. The entire exercise witnessed here strikes me as the pot calling the kettle black. Climate modeling is a political issue. No, it is not a Scientific issue, because it is not Scientific. Science relies upon direct observation – not extrapolation. Empiricism underpins Science. Modeling is an aid to Science. Theory is not Science. At best a theory is a guess at the consistency of Reality. Climate modeling is an exercise in Mathematics. Models are based on assumptions. Assumptions prove nothing.

    2) Geology as an empirical Science has demonstrated a long term trend in global climate. On average, every 100,000 years temperature peaks accompanied with a high in CO2 levels. Yet, the relationship is not consistent, nor does it explain the effect of shorter cycles - more precisly our current placement within all the cycles: long, medium, and short.

    Milankovitch in brief:

    CO2 and temperature trend not directionally consistent:

    Shorter cycles have an impact:

    3) The dominant opinion in Climate Science appears to ignore the above, or to acknowledge this with qualification. The most worrying element in this is the propaganda: human activities are causing climate change. Causality. If, at this moment you are not slightly uncomfortable, you might be practicing in the wrong field. [At the same time the statement can be so ambiguous as to allow the bigot to claim correlation.]

    4) I have a number of questions regarding climate modeling:
    a. How is “human activity” operationalized? In research, concepts have to be measurable. Data has to be obtained. That data must be accurate, valid, and reliable. It would appear that in Climate Science that this concept is largely imputed.
    b. What dataset used in Climate Science dates back more than 100 years (do recall the long term cycle of 100,000 years) and:
    i. Is continuous,
    ii. Measured consistently (across the globe, using the same methodology), and
    iii. Applied without extrapolation.

    5) As a suggestion this question may be relevant: if there is a natural long term trend, what impact does human behavior have on raising global temperature above the natural trend? Please explain to me how you will answer this question. Even propose an alternative to it if you must.

    Moderator Response:

    [RH] This post probably should be deleted for a multitude of reasons. But since several regular commenters seem eager to engage we'll let it stand as is. 

    Deon... Before continuing to post, you need to read the commenting policy document that is linked right above the text box. Please, try to stay on topic and keep your individual points limited to the appropriate threads. Discussing the science is a healthy thing. We just require that you follow certain rules in order to keep the discussions productive.

  37. It's not us

    dvaytw @89

    Imagine the Earth as a dinner plate, which as it rotates around the Sun always presenting its "face" towards the Sun. The surface area that the Sun irradiates is pi * r**2 where r = radius of the "earth". The "back" side is never irradiated.

    Now imagine that the plate is replaced by a ball of the same radius; the surface area has consequently increased. If the ball is not rotating on its own axis, then the surface area that the Sun irradiates is 2 * pi * r ** 2 (the surface area of a hemisphere). If the ball does rotate then (over the period of rotation) then each hemisphere spends half the time irradiated and half the time is dark. So the total area irradiated = 4 * pi * r**2.

    So the factor by which the Suns irradiance is diluted by the fact that the Earth is a rotating sphere, rather than a static diskworld is

    4*pi*r**2/(pi*r**2) = 4

  38. The oceans are warming so fast, they keep breaking scientists' charts

    sgbotsford @28

    It has been pointed out several times that your calculations omit any feedbacks, so there is no need to labour that point further.

    However, it may be worth your while to note that NASA give a best estimate of 14 degrees C as the global average taken over the 1951-80 period. (See here, at the bottom of the page.) Theis would equate now to a global average of around 288 K, rather than your...

              "But the planet averages about 300K"

    Unless, of course, you think that 12 degrees is nothing to worry about?


    Cheers    Bill F

  39. The oceans are warming so fast, they keep breaking scientists' charts

    wehappyfew @29

    Solar irradiance at our mean orbital distance of around 149.6 million kms, or the so-called "Solar Constant", is usually taken to be about 1,366 (+/- 0.5) watts/metre2 

    Therefore sgbotsford's quoted figure of approx 1,000 w/m2 at TOA does already account for an albedo value of ~ 0.3

    PS I like the Henry V reference, did you do anything special on the 25th October?

    Cheers  Bill F

  40. It's not us

    Thanks fellows for the info.  May I know a good source for a novice's understanding of the "disk vs. sphere question"?

  41. The oceans are warming so fast, they keep breaking scientists' charts

    Tom @33

    That is an excellent analysis but you should be clear, your 4.3C result is an intermediate step to the finale equilibruim temperature, the ESS value.

    Your 4.3C value is a 2100 value that is a waypoint to a global temperature that will be reached in 2500 that has not been seen on this earth in 4.5 million years.

  42. The Most Terrifying Papers I Read Last Year

    Well, OK, concerned, but not terrified.   Last time I was terrified was when I read Hansen's paper on the increasing 3-sigma heat wave events.  There is a strong signal of food production reductions where these events occur.  I suspect food (in)security will hit us harder, faster than sea level rise.

  43. It's the sun

    Will somebody please add to the "It's the Sun" rebuttal, a section explicitly focused on addressing the sub-myth that the Earth's temperature still is catching up to the TSI increase that peaked around 1960? 

    At the least, that section should show that TOA energy imbalance has continued to grow since then, in contrast to its shrinkage that would be required if insulation was constant, since input has been constant (or even decreasing) and increasing temperature requires increasing output.  For example, a good graph of imbalance was pointed to by jja in a comment.

    It would be nice if that new section also explained that temperature response lag to increased TSI was taken into account by the many regression analyses.

    Possibly relevant existing posts:  "Has Earth Warmed As Much As Expected?" and "How We Know Global Warming Is Happening: Part 2."  I recall that John wrote another relevant post that included energy imbalance, but I can't find it now.

  44. The oceans are warming so fast, they keep breaking scientists' charts

    sgbotsford @28, the 1 Watt/m^2 is the energy imbalance after 2.3 W/m^2 (natural plus anthropogenic) of forcing has been partially offset by a 1 C increase in temperatures.  That means 1.4 W/m^2 has resulted in a 1 C temperature increase.  Ergo we have an expected temperature increase of 0.71 C per Watt/m^2 (or 2.64 C per doubling of CO2).  That means we can expect an additional 0.67 C increase in temperature from the current energy imbalance assuming there is no further increase in radiative forcing.  With the conservative BAU scenario of RCP 6, that indicates an eventual temperature increase of 4.3 C.

    The difference between your and my calculated temperatures arises because my empirically based figure allows for the operation of feedbacks, which yours tacitly excludes.  That is important, because some feedbacks are slower than others, and empiricaly data will be biased towards a low climate response because it will not include the full effect of those slow feedbacks.  The result is that while uncertainty is large, such that the temperature increase could be larger or smaller than that projected by my simple calculation, it is more likely to be larger than smaller.

  45. The oceans are warming so fast, they keep breaking scientists' charts

    This graphic shows a collection of Top of Atmosphere energy assessments derived from Hansen & Sato (2010), Nuccitelli et. al (2012), Allen et. al. (2014), Durack et. al (2014) and a simple average analysis of 2010-2014 OHC from the NODC.

  46. The Most Terrifying Papers I Read Last Year

    This work adds to the understanding that authorities have on the unintended consequences of technological systems using fossil fuels. It helps them to make responsible decisions about implemetation of adaption measures to cope with expectations. For example, authorities in New York, London and the Netherlands are planning to use appreciable resources to provide a degree of protection from sea level rise and storm surges.

  47. The oceans are warming so fast, they keep breaking scientists' charts

    even more to the point:  the 1 watt per meter squared Top of Atmosphere energy imbalance is a permanent feature that will not go away until the earth reaches a new, warmer, equilibrium.

    In addition, the cumulative work of Nuccitelli, Hansen & Sato, Levitus, and Duack all point to the fact that this energy imbalance is DOUBLING double at a period of every 6-9 years.

    Finally, the fact that significant reductions in south-east asian aerosol emissions and arctic albedo conditions are looming, we will likely experience a rate of heat accumulation in the near future (5-7 years) that is nearly TRIPLE triple what we are currently experiencing.

    Welcome to the new era.

    Moderator Response:

    [JH] The use of "all caps" is prohibited by the SkS Comments Policy.  

  48. Stephen Baines at 07:08 AM on 25 January 2015
    Five bits of research that shaped climate science in 2014


    "I take it you were angry that I was trying to falsify something ?"

    No, they are annoyed because you are falsifying straw men and distorting the OP's message.

    First, in the absence of increasing CO2 the air temperatures would go through decades of warming and cooling naturally, because of factors like those explained in the OP.  The warming caused by increasing CO2 is simply superimposed on that variation.  So the fact that rates of atmospheric warming vary over decadal scales does not run counter to projections of the effects of CO2 on climate.  In fact, heat has been building up as espected based on CO2, given what we know of the forcings.

    Second, Antarctic sea ice is increasing in extent despite the fact that air and sea temperatures are also increasing and land ice on antarctica is shrinking.  Clearly other factors affect Southern Ocean sea ice extent in the austral winter, and the OP suggests there may be measurement artifacts as well (you failed to mention this despite it being the main point of that section of the OP!).

    Third,  the OP says nothing about warming in the Arctic being "offset" by mid latitude cooling.  That is your invention, disproven by the global temperature trends shown above.  The OP simply states that colder winters in some temperate areas are being linked to declining sea ice and warmer temperatures in the Arctic because of the effects on position and motion of the Jetstream. 

  49. The oceans are warming so fast, they keep breaking scientists' charts

    sgbotsford:  to add to wehappyfew's content, this is the warming we can expect without feedback if all GHG emissions stopped today.  I hope we can agree, that's not going to happen.

  50. The oceans are warming so fast, they keep breaking scientists' charts

    sgbotsford @ 28

    For a 1st order calculation, I would say you have it mostly right. You forgot to include the albedo of the Earth, which reduces the SW radiation absorbed.

    Re-doing your calculations, I get 

    dT = 0.43degK

    The much bigger problem is:  you seem to think the climate is easily modeled by a first order physics equation.

    Do you think it is possible that the albedo might change after a 0.4K average temperature change? Global snow cover has already declined quite a lot, especially in late spring and early summer when the albedo effect is largest.

    Ice sheets and sea ice might melt a bit more at higher temps, don't you think?

    Higher air and sea surface temps mean more water vapor... more greenhouse effect.

    Maybe these kind of effects are why we don't treat the climate as a 1st order physics problem.

    Another way to look at it... you have essentially calculated the warming due to current net forcings without any feedbacks at all. I think your number is pretty close to the accepted no-feedback value, so we are all in violent agreement about the basic physics of the greenhouse effect. Once you include the feedbacks, you should be much closer to the actual expected warming.

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