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Unforced variations: Mar 2014. Part II

Filed under: — group @ 28 March 2014

This is mid-month open-thread for all discussions, except those related to Diogenes’ comments. People wanting to discuss with commenter Diogenes should stick to the previous UV thread. All such discussion on this thread will be moved over. Thanks.

90 Responses to “Unforced variations: Mar 2014. Part II”

  1. 1
    prokaryotes says:

    Via Serendipity: Climate Model Bake-off

    Imagine for a moment if Microsoft had 24 competitors around the world, each building their own version of Microsoft Word. Imagine further that every few years, they all agreed to run their software through the same set of very demanding tests of what a word processor ought to be able to do in a large variety of different conditions. And imagine that all these competing companies agreed that all the results from these tests would be freely available on the web, for anyone to see.

    Then, people who want to use a word processor can explore the data and decide for themselves which one best serves their purpose. People who have concerns about the reliability of word processors can analyze the strengths and weaknesses of each company’s software. Then think about what such a process would do to the reliability of word processors. Wouldn’t that be a great world to live in?

    Well, that’s what climate modellers do, through a series of model inter-comparison projects. There are around 25 major climate modelling labs around the world developing fully integrated global climate models, and hundreds of smaller labs building specialized models of specific components of the earth system. The fully integrated models are compared in detail every few years through the Coupled Model Intercomparison Projects. And there are many other model inter-comparison projects for various specialist communities within climate science.

    Have a look at how this process works, via this short paper on the planning process for CMIP6.

  2. 2
    Steve Fish says:

    Prokaryotes, thanks for the reference. I know that this is off topic but in the spirit of your post I recommend Open Office for competition with Microsoft Office. It is free and completely open source. I have been using it for several years.


  3. 3
    Hank Roberts says:

    > decide for themselves which one best serves their purpose

    Wait, isn’t using all of them more accurate than using any of them? I’d think the approach is to use all the information available, not pick one with some purpose in mind.

  4. 4
    Earl Killian says:

    Are you going to try to grab the domain name when .science becomes a tld? I would hate to see a denier grab it.

  5. 5

    Which projection for atmospheric CO2 concentrations would you recommend? I’m looking for a projection that has been roughly accurate so far. Currently I’m using RCP 8.5 but that scenario might be too high on e.g. coal use later on, even with no efforts to reduce CO2 emissions directly?

    The few other projections I have looked at, including RCP 6, haven’t been that accurate so far and e.g. have too low population estimates.

    The projection is for the third chart found at the link below. (The page is an attempt at a succinct explanation of global warming for a private discussion — suggestions are welcome).

  6. 6
    owl905 says:

    Hopefully, this is the place to make my problem your problem. Here’s the problem:
    It’s an article from Climatewire reprinted in Scientific American:
    “Pollution Sours Pacific Ocean More than Expected”
    It’s explained fully in the article: the rate of soluble CO2 in the tropical Pacific Ocean waters is rising at a rate 50% higher (in places) than the atmospheric rate (3.3ppm versus 2ppm air). The data set is from seven buoys with measurements starting in 1998. ENSO and decadal signals have started to emerge, and the JISAO has determined that the water emerging with combined anthro and natural CO2 in the mix left the surface about 10 years ago.
    The problem, and there’s a wide variety of swag’s available, is trying to visualize mechanisms that would result in the water return upwards, warming up, and reaching the surface with an extra concentration charge of CO2.
    Whatever comes out in the form or research or the next round of studies, it’s a puzzle that hints of an unsuspected reservoir of acidified ocean.

  7. 7
    Random says:

    Any model-data comparisons yet? Soon? Ever?

  8. 8
    Vendicar Decarian says:

    3: “Wait, isn’t using all of them more accurate than using any of them?”

    Is using newtons laws and relativity to solve the same problem and averaging the results more accurate than using them separately?

    Well… No it isn’t, is it?

  9. 9
    Vendicar Decarian says:

    Can anyone answer the following?

    What is the typical simulated time interval dt, over which global climate models are integrated. Is it on the order of hours, minutes, or seconds?

    Do the models wait for the slowest cell to compute before moving on to the next iteration (strong coupling), or are the cells just computed based on the best available inputs from neighboring cells at the moment of the calculation (weak coupling)?

  10. 10
    pete best says:

    El nino is said to be forming – if it turns out to be a large one like 1998 what would it mean for us all. what predictions/projections sitting on a bed of 0.8C would make it any difference to the 1998 one?

  11. 11
    Martin Smith says:

    Is there anyone left?

    ‘[Nate] Silver said FiveThirtyEight is looking for a rebuttal from someone who has not weighed in yet on the dispute and “has very strong credentials.”‘

  12. 12
    Phil Mattheis says:

    First, thanks for splitting this thread out from the clutter. I’d given up on the open forum for this month, and was resigned to waiting for a clean start in April – though now is risk of losing the conversation as the month shifts again…

    Daily KOS has an extensive post regarding a huge Kelvin wave, was parked south of Hawaii, now being pushed by a negative Southern Occcilation Index to slowly head east across the Pacific. Magnitude of the numbers could be seen as start of an El Nino of some considerable size and duration.

    After a winter with arctic ice trends that have fallen to previous record lows, a shift into El Nino mode, with release of much of that stored heat would have all the more drama in impact. As an itinerant observer here, I’m in no position for credible predictions of the climate science, but I can imagine that combination leading to one of those jagged blips that resets the climate escalator, and becomes the new cherry to pick as baseline for the next inexplicable hiatus, that proves we all are nuts to think its getting hot in this pot of water (on the stove, fire set at ‘high’).

    For what’s worth, I’m conflicted between climate “confusionists” vs “confusioners”. Derivations of ‘denial’ all beg for argument, while ‘confusion’, at least on surface, implies some hope for sorting things out. My little niche of science is in human behavior, where is not uncommon to find that words we use can have real power.

  13. 13
    Andrew Jaremko says:

    Hi. Let me say first that I am not a scientist, although I do have a 1970 B.Sc. in physics. I’m a moderately regular visitor here, and am very interested in climate, the atmosphere, energy and much more.

    To that end, I’ve just finished some videos that compare Global Forecast System surface wind and total cloud water model animations with EUMETSAT cloud imaging animation for the months of November and December 2013. I made the model animations using the visualizations on Cameron Beccario’s earth site.

    The main video is at Cloud Truth and there are individual animations of the models and comparisons on the Cloud Truth playlist.

    I want to make videos that will help people visualize what’s happening in the atmosphere. I would appreciate any comments from the climate community on the videos.

    I intend to do more videos and am wondering if there’s a good way to get comments and corrections before I make the videos public. Any suggestions?

    Thank you all for your work here at Real Climate.

  14. 14
    Garry says:

    Just a heads up;

    There is a new web site;

    It is aimed at kids and is run by a climate denier whose main blog is here;

    As well as being extremely misleading about climate change, see here;

    The blogger has also been conversing on their blog with a scientist, conspiracy nut, and child sex offender; Oliver K. Manuel.

    I did post to the blog to inform ‘Reality check’ of this but my comment was censored and I was banned.

  15. 15
    Hank Roberts says:

    > is there anybody left
    I didn’t go through the list to check, but perhaps one or two of these haven’t commented on the Nate Silver thing; it’s a good list.

  16. 16
    Pete Dunkelberg says:

    2 uv’s – good idea RC. One for climate science, one for energy and solutions.

  17. 17
    Pete Dunkelberg says:

    Garrison Keilor says life is good in Minnesota and Cohen et al. 2012 say it’s just like the good old days:
    Arctic warming, increasing snow cover and widespread boreal winter cooling.

    The most up to date consensus from global climate models predicts warming in the Northern Hemisphere (NH) high latitudes to middle latitudes during boreal winter. However, recent trends in observed NH winter surface temperatures diverge from these projections. For the last two decades, large-scale cooling trends have existed instead across large stretches of eastern North America and northern Eurasia. We argue that this unforeseen trend is probably not due to internal variability alone. Instead, evidence suggests that summer and autumn warming trends are concurrent with increases in high-latitude moisture and an increase in Eurasian snow cover, which dynamically induces large-scale wintertime cooling. Understanding this counterintuitive response to radiative warming of the climate system has the potential for improving climate predictions at seasonal and longer timescales.

  18. 18
    numerobis says:

    Surprisingly, tamino doesn’t appear to have said much about Pielke on 538 — and is precisely the kind of data analyst we might hope Silver might be interested in hiring.

  19. 19
    Hank Roberts says:

    > tamino doesn’t appear to have said much about Pielke
    RPJr posted at Tamino’s a few days ago. Tamino responded.

  20. 20
    Pete Dunkelberg says:

    Hank @ 19 do you have a link? Eli has some

  21. 21
    Pete Dunkelberg says:

    Is this getting interesting? click through the previous years for comparison. Starting with at least the last 45 days of 2013, the overall Arctic temperature has stayed above the long term average for months. This looks like a record.

    What boosts Arctic temperatures during the long polar night? Putting a lid on it. Under clear dry Arctic winter skies our earthly energy flows back into space unimpeded. Given cloud cover the Arctic temperature soars, sometimes above 260 K.

    Could this generally, and this past winter in particular, have any connection to the Cohen et al. paper linked above @17 ? If you are trying to figure out our changing climate, I recommend the full paper. The link went awry last night. Here it is explicitly:

  22. 22
    Hank Roberts says:

    Sorry Pete, I don’t find it now, searching pielke
    maybe I dreamed it or the indexing hasn’t caught up

    In passing though, that search happened to turn up this reply to a question (that I asked both here and there) that I think is worth more attention from the physicists:

    BillD | March 13, 2014 at 4:48 pm |

    Hank—as an ecologist, I have to say that changes in seasonal timing (phenology), changes in populations, the impacts of changes in thermal stratification and ice cover (in lakes and oceans) and are very strong signals, stronger than what most ecologists (including me) would have expected from the temperature record. Sometimes I get a bit irratated when physicists suggest that temperature records are the only evidence. Evidence for rapid climate change from changes in ecology are very strong and, of course, completely independent of the temperature records.

    I know Jim Bouldin can comment on that, maybe over at his blog, but — physicists! phenology!

    The most sensitive instrument ever evolved for detecting changes in physical systems is: living systems. As Terry Pratchett wrote:

    It is often said that before you die your life passes before your eyes. It is in fact true. It’s called living.

    There are “Bioblitz” events trying to find everything living in an area that’s visible, given enough enthusiastic amateur eyes, just as a census. Do that repeatedly and the changes in the world will leap out at you.

  23. 23
    wili says:

    I’d like to follow up pete best’s and Phil Mattheis’ post with a humble suggestion that there be a main post on all things El Nino. This is likely to be the biggest climate story over the next two years, and it would be nice to be up to date on the latest in prediction, causes, consequences, and connection with GW.

    As for Minnesota, I recently saw the snarky headline “Evidence of Liquid Water on the Surface of Minnesota!” We are indeed starting to thaw out after a long by recent standards, but standard by longer comparisons, winter. 60F predicted for today!

  24. 24
    SecularAnimist says:

    BeezelyBub wrote: “… extinction deniers on the left … progressives seem to magically think … A lot of urban people think that … Renewable energy is a huge business run by mega corporations like General Electric, the same folks who brought us Fukushima … Solar manufacturing plants produce 500 tons of hazardous sludge each per year …”

    So you set up a Diogenes-free thread, and along comes another boorish ranting troll spewing interminably verbose incoherent drivel full of attacks on cartoon strawmen (“extinction deniers”, “progressives”, “urban people” — oh my!), inanely contentious non sequiturs (renewable energy = big business = Fukushima) and ludicrous falsehoods.

    The moderators have my sympathy.

    [Response: We are trying to keep this thread tedium free as well – that one slipped by. Thanks – gavin]

  25. 25
    Dave Peters says:

    Re: #449 old March UV thread; Within the context of discussions unbounded by known physics occurring upon policy threads, wherein I spend much time, this peek at contemporary contrarians (who seem so constrained), was for me, quite helpful. Thank you for flagging it, MARodger.

  26. 26
    Pete Best says:

    The new report coming out regarding the impacts of ACC/AGW have had a few people drop out on the substance, namely economists. Wonder why that would be?


  27. 27
    sidd says:

    I have remarked on the possibility that reduced expansion due to deeper ocean warming is masking increasing contributions to sea level rise from ice melt. I see that the usual suspects are working on it

    Cazenave(2014) doi:10.1038/NCLIMATE2159

    Unfortunately they only use 0-700m data for the period 1994-2006, and Argo down to 1500 m thereafter. The estimated error in the thermosteric component is quite large (1.4 mm/yr)

    The paper is more concerned with removing shorter term (ENSO and other) fluctuation from sea level rise measurements, briefly they find around 3.2 mm/yr over the last two decades from satellite altimetry.


  28. 28
    Hank Roberts says:

    > isn’t using all of [the models] more accurate
    > than using any of them?”

    Serious question, despite VD’s snark; I think I recall this being discussed a while back in comparing models, that the combined result is closer to matching reality. Anyone help me check that recollection?

  29. 29
    Brian Foster says:

    Here is my big picture question: Given that the earth was beginning a cooling phase until AGW, heading toward an ice age in roughly 1500 years, at what point will the diminishing sunlight intensity overcome the insulation provided by the excess CO2? Beyond that point will the cooling by lowered solar inputs correct for the anomaly quickly or will it just delay the onset by a couple hundred years?

  30. 30
    Mal Adapted says:


    I have remarked on the possibility that reduced expansion due to deeper ocean warming is masking increasing contributions to sea level rise from ice melt.

    I’ve wondered about that, and your comment impelled me to investigate. I had understood that water isn’t compressible, so I thought the same increment of heat should cause the same increment of expansion regardless of depth. According to the USGS:

    But, squeeze hard enough and water will compress—shrink in size and become more dense … but not by very much. Envision the water a mile deep in the ocean. At that depth, the weight of the water above, pushing downwards, is about 150 times normal atmospheric pressure (Ask the Van). Even with this much pressure, water only compresses less than one percent.

    Seems like water compression would be a small component of the SLR noise, no?

  31. 31
    Rick Brown says:

    Hank @ 28: re multiple models versus any one model

    Hank, this citation may be a bit out of date, but I suspect that the principle isn’t.

    Lambert and Boer (2001) show that for the CMIP1 ensemble of simulations of current climate, the multi-model ensemble means of temperature, pressure, and precipitation are generally closer to the observed distributions, as measured by mean squared differences, correlations, and variance ratios, than are the results of any particular model.

  32. 32
    Pete Dunkelberg says:

    Brian, 1) sunlight intensity will not diminish. That’s not how it works. Instead it works like this, sort of. Summer sunlight in the northern hemisphere (NH) diminishes and increases in the southern hemisphere. Further cooling (if we were doing that) would come from, among other things, an expanding summer NH snowline, hence greater albedo for the planet. (The SH has much less land area, especially since Antarctica does not count for this purpose. It stays icy anyway). Changes in CO2 also occur. A colder ocean absorbs it for one thing.

    NH summer snowline is receding due to warming from CO2. No ice age is coming, or at least not for 125 k years. This was probably settled by around 1900 or not much later.

  33. 33
    owl905 says:

    @29BrainFoster – “heading toward an ice age in roughly 1500 years” There’s no expected Ice Age in ‘roughly 1500 years’. The Holocene Inter-glacial stability was already an anomaly before civilization added to the mix. It didn’t reach a ‘bishop’s peak’ and fall back – it flattened out about 7,500 years ago.
    “at what point will the diminishing sunlight intensity overcome the insulation provided by the excess CO2?” It won’t. The 6dC swing has been shifted upwards by almost 2dC (so far).
    The last glaciation period, post-Eemian started with approximately 400 years of ‘sudden’ cooling (possibly volcanic driven). It was followed by stuttering colder and drier and icier, with reverses to warmer intervals, that lasted about 40,000 years. GHG levels are now higher than they were at the start of the first glacial period, the Huronian, 2.4 million years ago. Long before any cooling that could produce a serious glaciation period, the concentrated Greenhouse Effect will serve up Hothouse Earth and Garbage Dump Earth.

  34. 34
    Pete Dunkelberg says:

    I doubt that the CMIP group is doing it wrong. Perhaps the clarification you need is by now so obvious to the CMIP group and to Steve that it went unsaid.
    Steve is reasonably well acquainted with the subject and may know what he is talking about.

    “Well, that’s what climate modellers do, through a series of model inter-comparison projects.” he says and links to a paper about the next round of doing this. Check it out.

    So maybe your objection is muddled. First, distinguish between averaging all models (when the purpose of CMIP is pick out the best one(s) or best for a particular purpose, and averaging multiple runs of the same model with different initial conditions, and using model A to study process a when A happens to be quite good at a and model B is not.

  35. 35
    Pete Dunkelberg says:

    Thanks Rick Brown for that link ;)

    plus Tweet from Mike Mann
    Michael E. Mann @MichaelEMann

    Disinformation campaign to fool public into thinking new #IPCC report downgrades risk (it does opposite) is something to behold. #Immoral

  36. 36
    Hank Roberts says:

    Thanks, Rick Brown; same reference appears in the more recent report

    the hypothetical economic costs associated with climate events can be reduced by calculating the probability of the event across the ensemble, rather than using a deterministic prediction from an individual ensemble member.

    That’s the reference I was recalling.

    Same point; picking one model to affirm the answer you want is less accurate than using all the available information to get closer to what’s real.

  37. 37
    Dave Erickson says:

    John Christy wrote an article that appeared in the popular press ( where he makes this claim:

    For example, I analyzed the tropical atmospheric temperature change in 102 of the latest climate model simulations covering the past 35 years. The temperature of this region is a key target-variable because it is tied directly to the response to extra greenhouse gases in models. If greenhouse gases are warming the Earth, this is the first place to look.

    In a rather disconcerting result, I found all 102 model runs overshot the actual temperature change on average by a factor of three. Not only does this tell us we don’t have a good grasp on the way climate varies, but the fact all simulations overcooked the atmosphere means there is probably a warm bias built into the basic theory _ the same theory that we’ve been told is “settled science.” I don’t know about you, but to me, being off by a factor of three doesn’t qualify as “settled.”

    Anyone seen this result? Any response? Gavin? This should be right in your wheelhouse…

    [Response: There are a number of points worth making. First, the ‘settled science’ trope is just a rhetorical strawman (see my 2009(!) comment on same). Second, his ‘for example’ is another rhetorical flourish to imply that many other aspects show the same thing – this is simply not true. There are countless metrics that one could look at – and at best we would expect some to be higher, some lower and a lot about right (which we do). Only pointing to one metric that is lower than observed is cherry-picking. But all of that is somewhat eclipsed by the fact that Christy’s figure is not properly published (and so it is not really clear what he is plotting), and has already been called out for inconsistent smoothing, selective baselining and the lack of error bars on the observations (which are large). A clearer view of how tropospheric trends in the models match the observations is seen in Santer et al (2012), in particular fig 3. – gavin]

  38. 38
    sidd says:

    Re: thermal expansion coefficient of water as a function of depth/salinity

    i hope the url works, but the gist of the table at the link is that deeper ocean has smaller thermal expansion coeff


  39. 39
    Alastair McKinstry says:


    Can anyone answer the following?

    | What is the typical simulated time interval dt, over which global climate | models are integrated. Is it on the order of hours, minutes, or seconds?

    It typically varies across the model components. Eg. in the EC-Earth model, we had 10 minutes in the atmosphere, 20 minutes in the ocean, 1 hour in the sea-ice model.

    | Do the models wait for the slowest cell to compute before moving on to the next iteration
    |(strong coupling), or are the cells just computed based on the best available inputs from
    | neighboring cells at the moment of the calculation (weak coupling)?

    I am not aware of any CMIP5-class models that do this “weak coupling” method. Various load-balancing methods are used to average-out the workload per node to avoid slow cells delaying the overall model.

  40. 40
    prokaryotes says:

    Climate sceptics successfully deleted the German Wikipedia article on the scientific consensus on climate change. There is currently a discussion/attempt to revert the deletion (German).

  41. 41
    MARodger says:

    sidd @38.
    URL is fine, but does not the table show an increasing coefft of thermal expansion with depth?
    Take the numbers for 5ºC @ 3.5% salinity.
    Depth,… Coefftx10^6
    Surface… 114
    2000m,… 157
    4000m,… 196
    6000m,… 230
    8000m,… 246
    10000m,. 287
    I assume the physics works like that because, while the water compresses with pressure/depth, it still requires the same wiggle room to contain the extra thermal energy.
    The graph down this link shows the region of the temperature/pressure graph where ‘thermal expansivity’ increases with pressure for pure non-salty water. Salinity is however a significant factor.

  42. 42

    #21, Pete Dunkelberg,

    Actually most of the warming is due to reduced sea ice in the Bering Sea and the Atlantic ice edge, not due to clouds. The warming over the pack itself looks fairly normal, there are two reasons for this: 1) disruption of the climatological atmospheric inversion, 2) thinner sea ice allowing greater heat flux through than over most of the climatology mean period.

    Using NCEP/NCAR I’ve plotted 1 Jan to 28 Mar surface air temperature north of 80degN, the DMI page uses a different reanalysis north of 80degN.

    The top right quarter shows the strongest warming, this is due to reduced ice cover around Svalbard. Because there was typically always extensive ice in that sector the baseline average is something of the order of -20 degC. The ice insulating the atmosphere from the ocean. At present the ice edge in the Atlantic is further north than average, so open ocean is keeping temperatures much warmer than average.

    The vertical cross section of the atmosphere shows that the warming over that upper left quarter is surface hugging:
    This shows that the source of the heat is the surface.

  43. 43
    sidd says:

    Re: thermal expansion coeff of seawater

    The temperature is not constant from surface to depth. at 4000 bar the temperature might be -2C while it is 30C at the surface. The salinities also change but i think 35 parts per thousand is a good place to start.

  44. 44
    Hank Roberts says:

    Possibly interesting:
    Herman Daly and others

    Center for the Advancement of the Steady State Economy

    Economics models have begun to look a little better
    Sornette’s — — for example

  45. 45
    Mal Adapted says:

    Re: thermal expansion coeff of seawater, it’s clear the issue is more complicated than I thought. Thanks, Sidd and MARodger.

  46. 46
    Eric Swanson says:

    #37 – Dave Erickson – Christy and Spencer are promoting a new graph of satellite vs model results. Spencer presented the graph with his written testimony at a hearing last 18 July before the Senate environment and Public Works committee. See Figure 2 [HERE].

    Notice that Spencer uses tropical mid-troposphere satellite data, which I take to mean their TMT product. Christy’s latest version adds more model runs and averages the model runs into a single curve, then reduces the Y-axis scale a bit to make the model results look larger. Trouble is, the TMT includes a cooling influence from the stratosphere, a long known problem which was the reason they developed their TLT back in 1992. They also show radiosonde data, which may have been adjusted by simulating TMT radiances at the TOA. If so, we can only guess whether they applied the same “adjustment” to each model run, since they provide no references for their efforts. I suspect they didn’t, which would thus make the figure appear to show a great difference between the model results and the data. They also do some other funny things, such as adjusting the curves so that the trend lines cross at 1979, which forces the model results upward more than the TMT and sonde data sets, given that apparent greater trend in the model results. Spencer claims to have applied a 5 year running average on the TMT and sonde data, then shows 34 data points in the graph. But, curiously, a proper moving average must reject 4 years of data out of the 34 years available from 1979 thru 2012.

    I think that this is all a repeat of their claim that there is a “missing warming” in the upper tropical troposphere, a claim which has seen considerable debate, as discussed in Santer et al. (2012).

  47. 47
    Pete Dunkelberg says:

    Chris @ 42, thanks mucho for that analysis! So the unusually high base line for Arctic temps (perhaps starting sometime last November?) is the warmth near Svalbard. The high jumps in Arctic temperature, which occur nearly every winter, must still be due to cloudiness? And last year’s cold spell around day 50 would indicate very clear skies?

  48. 48
  49. 49
    MARodger says:

    sidd @43.
    That is a very helpful observation. I was thinking the deep ocean has such a small temperature gradient that it would have no impact. But…
    Digging the numbers you linked to @38:-
    Depth……-2ºC,….0ºC,….5ºC,.. 20ºC
    Surface,… 23,….. 51,…. 114,… 207
    2000m,….. 80,… 105,… 157
    4000m,… 132,… 152,… 195
    6000m,… 177,… 194..,.. 230
    8000m,.. …..,….. 231,…. 246
    10000m,.. …..,… 276,…. 287
    At depth, say 2,000m to 6,000m where there is still large ocean volumes, the temperature gradient(as per this Wiki graph) is, what, 1ºC per 1000m? If so, the coefft of thermal expansion will be still increasing with depth but by a significantly less amount.

    Importantly though, through the top 2000m where there is by far the biggest temperature gradient, the coefficient does reduce with depth because of that temperature gradient – dropping possibly by 20% or so. And of course, that is the very bit of the ocean presently seeing the big increases in OHC.
    So with that caveat, I would sign up to the coefft of thermal expansion in the oceans reducing with depth.

  50. 50