The warmest year…again

I haven’t, yet, written anything about 2016 becoming the warmest year in record. That’s partly because it appears to have been virtually certain that it would be for a few months now, and partly because it’s been extensively covered elsewhere. There’s Realclimate, Sou, Stoat, Tamino and Carbon Brief, to name but a few. Essentially, 2016 is a record in all of the major surface temperature datasets, NASA, NOAA, Berkeley, and HadCRUT. This is also the third year in a row in which global surface temperatures have broken the record, something that has not happened since records began.

By adjusting for ENSO events, it can be shown that 2016 would still be a record in the NASA and Berkeley datasets, but not in the HAdCRUT and NOAA datasets. This is, however, mainly because the latter two datasets don’t cover the Arctic as well as the former two datasets, and the Arctic has been particularly warm. There seems to be a bit of a fuss about the role played by the recent ENSO events, but I think that rather misses the point; the last 3 years have each been records. Removing the effect of ENSO (and, in some cases, solar and volcanoes) doesn’t change this, it simply illustrates the likely underlying anthropogenic trend. As this Realclimate post illustrates, that we’re continuing to break records is itself indicative of an underlying trend; if the climate were stationary, we’d expect the number of records to decrease with time, not increase.

It seems to me that there is also a chance that we could well be heading for a period of accelerated warming. I might regret suggesting this, but Gavin Schmidt seems to suggest the same in this article. We appear to have had a period of slower than expected warming, and we can’t simply build an ever increasing planetary energy imbalance; surface temperatures will eventually have to increase to close the energy gap. I guess it’s possible that the recent warm years might have closed the energy gap enough that we won’t see much additional acceleration. On the other hand, there are indications that the pattern of sea surface warming, in particular differential warming across the Pacific, has lead to more negative cloud feedbacks and, potentially contributed to the slower surface warming. Maybe this can continue, but I don’t know how long one can sustain differential warming across a major ocean basin. It will be interesting to see what the ocean heat content does in the coming years.

Anyway, that’s about all I was going to say. I suspect the next few years are going to be interesting, for many different reasons. It will be intriguing (although, probably also rather frustrating) to see all the various different ways in which these recent records will be dismissed and what will be promoted when 2017 fails to be another record, which seems quite likely.

Advertisements
This entry was posted in Climate change, Climate sensitivity, ClimateBall, Gavin Schmidt, Global warming and tagged , , , , , , , , , . Bookmark the permalink.

54 Responses to The warmest year…again

  1. exactly right, imho. I will note that the weekly average of CO2 was 387.14 ppm when Obama was inaugurated in January 2009 and the weekly average was 406.14 when Trump was inaugurated. 19 ppm increase during the Obama 8 years. Could have been worse, I guess. If eloquence could resolve our climate problem, Obama’s work would done the trick. He definitely talked the talk.

    So, here we go, the Trump years. I heard “all of the above” energy policy approach remains in place, but eloquence, any semblance of traditional polite behavior, etc. is out the window. I expect that changes in the rate of increase between the Obama and Trump years will be exaggerated and spun, but I know this website will remain a reliable source of information and analysis.

    Our species is moving slowly away from fossil fuels and the the pace of our move appears to have little to do with the beliefs of our elected leaders. We have to bring the changes that are coming.

    Keep up the great work on this website. You are helping us with the persuasive work that must be done to mitigate the catastrophe of AGW.

    Mike

  2. Magma says:

    Considering recent temperature reconstructions of the Holocene with their reasonably constrained error bars and the reasonably understood forcings that drove the Holocene Thermal Maximum, we may just have experienced the warmest year in the past 125,000 years. But even if that fuzzy mark, difficult to pin down with certainty, wasn’t passed in 2016, then it certainly will be in the next decade or two. Instead of a sense of wonder or dread, on far too many websites and media comment forums I see brainless comments such as:
    “Oh yeah? What was the temperature on [insert random date in the distant past]?”
    “So who was reading thermometers 50,000 years ago?”
    “25,000 years ago where I live there used to be a mile of ice. Did SUVs melt it?”

    Few would care if this was just the left-hand tail of the global village gibbering away to itself. But when the tail includes some presidents, prime ministers, cabinet secretaries/ministers, CEOs and owners of media conglomerates, there’s reason for concern.

  3. Ok, I am sorry, but rant warning …

    There are many kinds of intelligence apparently: scientific, emotional, artistic, musical, spiritual… and so maybe I should not judge how the warming of the planet is communicated by scientists far brighter than me. But wtf do we keep getting ensared in these ‘this year is warmer’, ‘no it is a pause’ type silliness? This is not a pissing contest, surely.

    I understand that from a climate scientists perspective, understanding annual perturbation is both interesting and important, and worthy of study (no question, especially as we move into attribution studies), but for Joe Punter it is confusing and suggests a lack of consistency in the messaging. ‘So is it going up, down or level; is the world warming or not?’, s/he asks from atop the Clapham Omnibus.

    Taking a 30-year rolling average shows an unambiguous upward trend, that smooths out all those variabilities (confusion erased), so from a ‘is the world warming’ perspective, wtf would you NOT always use that to communicate the warming? Why would you ever fall into the trap of debating with some dullard from the Daily Fail, or Daily Torygraph, or Daily Whatever, about this years ‘up’ or is it ‘down’, when the trend is assuredly and incontrevertibly UP!?

    I think I want to invent “communication intelligence” because it seems lacking in this arena of ‘is the world warming’ amongst some who are assuredly super intelligent in other ways.

  4. Magma says:

    @ Richard Erskine
    By all means, rant away. A large part of the effort, energy and precious time wasted arguing that water is wet, fire is hot, and up is not down arises because climate scientists can’t (metaphorically) punch lying іdіоts in the nose. I never had any interest in joining debating clubs or teams in high school or university because the core of the activity seemed fundamentally dishonest to me. Yet some contrarians have made a comfortable living from it, and highly intelligent scientists fallen for the error of ‘debating’ them in good faith.

    It’s little surprise that those who haven’t done so have been relentlessly targeted, like James Hansen and Michael Mann, and to a lesser extent Gavin Schmidt. I’m not sure how Richard Alley has escaped… maybe he’s just too enthusiastic for anyone to hate.

  5. JCH says:

    Because of what is not known, it is possible climate sensitivity is higher than thought, and that the climate could do several decades of “linear” warming in a decade, or less, and what are you going to tell people then?

    Explain every wiggle.

  6. Harry Twinotter says:

    I would expect the rate of warming to accelerate at some point as positive feedback effects become more significant. And because the climate models projections show an acceleration to be the most likely trajectory.

  7. angech says:

    “It will be intriguing (although, probably also rather frustrating) to see all the various different ways in which these recent records will be dismissed and what will be promoted when 2017 fails to be another record,”
    Too pessimistic ATTP.
    Harry Twinotter gives 2 reasons, positive feedback effects become more significant and the climate models projections show an acceleration to be the most likely trajectory,for the warmest ever year 2017 which will be 4 years in a row.
    JCH says climate sensitivity is higher than thought and further back that an El Nino is possible on the cards for 2017. January is warming nicely now., well in Australia but it is middle of summer.
    smallbluemike mentions the Trump inauguration which will pump more CO2 into the air than ever.
    Whats not to like?
    Realclimate, Sou, Stoat, Tamino and Carbon Brief, would all say it will be warmer.
    Cheer up.
    On global warming land and sea records. Skeptic concerns about data altering will soon hit a brickwall of more standardized stations. The data should be more consistent hence if warming or a pause is happening or cooling occurs I think the current stations will show this. More satellites and more knowledge means better integration of land sea and satellite data. Hopefully we can all be arguing from the same page in future.

  8. T-rev says:

    I went to the linked Independent Article, anything with Gavin Schmidt is worth a read, stayed for the comical comments … 🙂

  9. @JCH – its where you start. Pedagogically you don’t start with every wiggle, surely?

  10. angech,

    Skeptic concerns about data altering will soon hit a brickwall of more standardized stations.

    I think you underestimate some people’s ability to find things to be concerned about.

  11. Marco says:

    ….see Ron Graf’s reference elsewhere to a new post on CE where ‘concerns’ are uttered about data altering in a specific location.

  12. russellseitz says:

    “I think you underestimate some people’s ability to find things to be concerned about.”

    Like polemic overkill as the history of Cold War anti-nuclear activism repeats itself in the Climate Wars ?

    Not content to let the numbers speak for themselves, Hollywood, Sundance and PBS are promoting a dystopic vision of the much-modeled future , turning it into a sort of scientific Lake Woebegone, where all threats are existential, and all the parameters are grimmer than average.

  13. quite right, magma.

  14. Gavin writes:
    But he added that the figures “should serve as a reminder that short-term variations should not be conflated with long-term trends. One is not predictive of the other”.

    And then, apparently without trying to be ironic, writes:

    “None of them [‘skeptics’] are going to be jumping up and saying ‘look how much it’s warmed since 2014’, none of them are going to say that,” he said.

    Yes, the atmosphere gained a lot of heat during 2015 and 2016.
    But how much of that heat came from the oceans which lost a lot of heat during 2015 and 2016?
    Both oceans and atmosphere would seem likely to regress toward longer term trends.

    As for acceleration of trends, we’ll see. RF rates have decelerated from peak annual rates around 1989, but have ticked up recently from changes in N2O and CH4.

  15. anoilman says:

    angch: AHAHAHAA!!!
    “The data should be more consistent hence if warming or a pause is happening or cooling occurs I think the current stations will show this.”

    Please define consistent? All data gathered has calibration and adjustment issues. This is normal, and the basis for all statistics on the planet earth today. Health care… manufacturing… military… forestry… The list goes on and on and on and on… (Personally I find it hilarious that skeptics claim the forestry industry is faking data, and the military commits treason. Then walk away from providing evidence. Gutless and slimy.)

    Its pretty obvious that pseudo skeptics will BS and bluster their way through whatever they feel is important. At all times they will ignore the data, and selectively some random minutia to complain about. There is no end to what they will complain about.

    By the way… is Judith Curry planning to continue working for oil and gas?

  16. Steven Mosher says:

    “On global warming land and sea records. Skeptic concerns about data altering will soon hit a brickwall of more standardized stations. ”

    We’ve had standardized stations in the us since 2002. Even before if you actually look at stations not formally designated as CRN… (mesonets). And we know that non standard stations don’t diverge from these. That doesn’t stop skeptics from….

    A. Claiming there is no global average…essex
    B. Claiming the coverage is too sparse to know anything.
    C. Claiming CRN might be tainted
    D. Arguing that raw data isn’t raw.
    E. Arguing that temperature is a bad metric.
    F. Claim that Jones lost all the data.
    G. Arguing that uncertainty on monthly values make any claims impossible.
    H. Arguing it’s all a random walk.

    And more.

    Of course you can demonstrate that all of these are wrong..But that doesn’t stop people. .

    Kinda like hands up don’t shoot.

  17. > Not content to let the numbers speak for themselves

    Worse than that:

  18. if the deniers really believed what they say, they would be buying shoreline real estate. It’s value is depressed by the possibility of AGW and SLR. Come on, put up or shut up.

  19. Phil says:

    Eddie:
    But how much of that heat came from the oceans which lost a lot of heat during 2015 and 2016?

    According to this, OHC rose in 2015.
    Whilst El Nino events should decrease OHC, they now occur against a backdrop of OHC uptake due to global warming from increasing GHG. So, it doesn’t seem obvious to me that El Nino’s years should be marked by a decrease in OHC.

  20. russellseitz says:

    Now is understanding tovarisch Willard !

    Numerism is Counters Soviets plus the electrocution of the Commentariat

  21. Willard says:

    There’s no “is” in Russian, Russell, and here’s for your concerns about your favorite meme:

    Mr. Vladimir: I just want to say one number to you. Just one number.
    Estragon: Yes, sir.
    Mr. Vladimir: Are you listening?
    Estragon: Yes, I am.
    Mr. Vladimir: 3.

  22. JCH says:

    OHC – 0 to 2000 meters

    2014-3 – 20.874861
    2014-6 – 19.914608
    2014-9 – 18.526079
    2014-12 – 21.123238

    2015-3 – 23.416958
    2015-6 – 22.368597
    2015-9 – 21.546423
    2015-12 – 22.271896

    2016-3 – 22.996992
    2016-6 – 20.037872
    2016-9 – 19.772640

    Peak El Niño and OHC…

    4th quarter is not out yet. In the 3rd quarter the drop in OHC slowed to a crawl. Will it go up in 4th?

  23. JCH: You provoked me to finally do a comparison I’ve been curious about for a while, which is to compare a de-trended OHC (0-2000m) against the MEI and see how they matched up. And… I’m a bit surprised. I really had expected to see an OCH/MEI relationship wherein de-trended OCH dropped when MEI rose, and rose when MEI fell, but it is hard for me to see any kind of consistent pattern between the two timeseries. (for what it is worth, the Excel “correl” function returns 0.28, which is pretty low, and there isn’t any obvious lag to introduce).

    (0-700 looks much the same as 0-2000)

    -MMM

  24. Joshua says:

    ==>

    A. Claiming there is no global average…essex
    B. Claiming the coverage is too sparse to know anything.
    C. Claiming CRN might be tainted
    D. Arguing that raw data isn’t raw.
    E. Arguing that temperature is a bad metric.
    F. Claim that Jones lost all the data.
    G. Arguing that uncertainty on monthly values make any claims impossible.
    H. Arguing it’s all a random walk.

    And more.

    ==>

    —————–

    As a fan of irony, my favorite part is the recursive link…

    A. Claiming there is not global average…
    [..]
    H. Arguing it’s all a random walk
    […]

    [Variable]. Claiming that there has been a “pause in global warming” and that “alarmists” are adjusting the data to hide that pause.

    And then back to….

    A. Claiming there is no global average.

    ——————–

    The ability to argue that there has been a pause in global warming and that there is no such thing as global average is, IMO, the beautiful and artful hallmark of a “skeptic”

  25. Phil says:

    Climatemusings:
    Is there not an annual cycle too? JCH’s quarterly figures max during SH summer (Q1) and min during NH summer (Q3). That is commensurate with the distribution of water on the planet, no?

  26. JCH says:

    My suspicion is part of the variability is an ENSO driven OHC back and forth, above and below, 2000 meters. And I suspect people have been thinking of that as being a release to the atmosphere.

  27. wehappyfew says:

    JCH,

    Another place the OHC may slosh around – to and from – is the poles. ARGO doesn’t cover much high latitudes, and none at all under the ice. The Arctic has been particularly warm in 2016, so maybe the ENSO surge of heat made it to the Arctic, melted some ice, and warmed some Arctic and sub-Arctic ocean water… not measured by ARGO.

    The Antarctic is at record low sea ice area (and probably volume). Subsurface ocean heat might have something to do with that too, and the SST of the Southern Ocean are at record levels by 0.5 degC.

  28. paulski0 says:

    JCH,

    My suspicion is part of the variability is an ENSO driven OHC back and forth, above and below, 2000 meters.

    High frequency variability within 0-700m depth seems to explain most of the high frequency variability in the 0-2000m depth record, so I doubt anything happening below 2000m is more than negligible in this respect.

    Phil,

    I was going to say about the apparent annual cycle. But I’m not sure it’s due to distribution of water. There is a global seasonal cycle, which peaks around March/April and troughs around August/September, but I think this is meant to be removed in the NODC product shown above. The appearance of a seasonal cycle only really begins in 2012. Focusing on that period (2012-present) and splitting into three latitude bands suggests the appearance of an annual cycle may be coincidental, or quite complex if not coincidental.

    Looking at 2012, the 2nd quarter drop is due to SHExt+Tropics and then the 3rd quarter low is entirely due to a big drop in the NHExt. In 2013 the 2nd quarter drop is due to SHExt+Tropics again, but the 3rd quarter low is almost entirely due a big fall in the SHExt this time. I could go on, but essentially the reason for the apparent annual cycle seems to change every year.

    Regarding the ENSO-OHC link, you could focus on the ENSO region, e.g.:

  29. JCH says:

    Thanks Paul S. Especially 2nd graph. Looks a lot like the ONI record.

  30. angech says:

    anoilman says:
    “By the way… is Judith Curry planning to continue working for oil and gas?”
    Have you stopped ………..
    working for oil and gas also?
    Had to laugh at that question.
    Joshua says: January 23, 2017 at 10:27 pm
    Thanks Josh, without you I would have been sorely tempted to break my second resolution.
    OHC , worth mentioning again, All that 10 to the 23 joules of energy hardly worth 0.07 degrees Celsius.
    wehappyfew says: January 24, 2017 at 1:05 am
    The Antarctic is at record low sea ice area (and probably volume).
    Only if you are more specific.
    It might surprise you to know that the Arctic has been ice free many times in the past, but I doubt that.
    What you should say, specifically, is that The Antarctic is at record low sea ice area (and probably volume) for the current satellite era.
    You should also admit that a 36 year observation is hardly time enough for this to be a very meaningful comment.
    You could also note, for instance, that only 2 years ago the global sea ice area was at a record high [for the satellite era].
    Both your observation and mine are therefore specious in the extreme, though both are very true, further comment please?
    For instance as to why such divergent claims can both be true and why you promote one but ignore the other?

  31. JCH says:

    OHC , worth mentioning again, All that 10 to the 23 joules of energy hardly worth 0.07 degrees Celsius.

    Too funny.

  32. What angech fails to make clear is that almost half of the increase in OHC has been in the upper 300m. It kind of works the other way to what angech is implying. We expect the mixed layer (upper 50 – 100m) to equilibrate with the surface quickly. This means that if the surface warms by 1K, this layer will also quickly warm by 1K. The warming of the deeper layers will, however, take much longer. However, they will eventually warm to equilibrate with the mixed layer.

  33. Phil says:

    Paul S, very interesting – thanks from me too

  34. JCH says:

    Or, .07 ℃ is pretty solid evidence the enhanced greenhouse effect is real; natural variation is not going to cool a GD’d thing; climate sensitivity is not low; luke warming is looking like a cruel fairy tale; and climate skepticism is a complete CargoCult Etc. con job.

  35. However, they will eventually warm to equilibrate with the mixed layer.
    Probably not.

    “90 % of the total volume of ocean is found below the thermocline in the deep ocean. The deep ocean is not well mixed. The deep ocean is made up of horizontal layers of equal density. Much of this deep ocean water is between 0-3 degrees Celsius (32-37.5 degrees Fahrenheit)! It’s really, really cold down there!

  36. TE,
    Yes, I know it is cold down there. You misunderstand what I mean. I don’t mean it will warm until it is isothermal. I mean it will warm until, on average, the flux of energy into the deep ocean matches the flux out of the deep ocean. If you warm the upper layer, then (unless I’m mistaken) you would expect energy to diffuse into the deep ocean (slowly). This will continue until the rest of the ocean has warmed to essentially halt the diffusion of energy into the deep ocean. Hence, arguing that much has happened because the change in average temperature of the ocean is small misses (intentionally?) that most of the warming so far has been in the upper layers.

  37. anoilman says:

    angech says:
    “By the way… is Judith Curry planning to continue working for oil and gas?”
    Have you stopped ………..
    working for oil and gas also?

    I work in oil and gas, and I’m not looking forward to being put out of work. I love my work, and putting me out of a job is what we should be doing.

    Its not for lack of trying to get out of oil and gas. Its just that I can’t find another 6 figure salary with only 4 hours a day work for my talents in the green sector. I’ve got the time to get a masters degree or PHd… but I can’t figure out a field

    In any case, there has been no evidence that the science of global warming is wrong. None nadda zippo. There is not alternative theory for the planet to heat up… none nadda zippo. Given that my livelyhood has serious side effects I’ve been searching long and hard for something which can put my mind at ease. I can console myself with the fact that many of my efforts have reduced environmental risks and damage. My current efforts will also put many drillers and oil field engineers out of work.

  38. There probably are knowledge gaps wrt oceans which we’re all too ready to fill with speculation.

    But do consider that the warmer the surface gets, the more stable the stratification and the lower the level of thermal exchange even though the potential of thermal exchange is greater.

    And, the warmer the deep ocean might get, the more readily those waters are displaced by near freezing waters created at the poles.

    Diffusion, which acting alone would tend toward an isothermal profile, is very small compared to larger scale dynamics.

  39. TE,

    But do consider that the warmer the surface gets, the more stable the stratification and the lower the level of thermal exchange even though the potential of thermal exchange is greater.

    And yet we’ve seen warming all the way down to 2000m?

    And, the warmer the deep ocean might get, the more readily those waters are displaced by near freezing waters created at the poles.

    I was referring to the whole ocean.

    I’m not even sure that you’re correct (although I can’t claim extensive expertise about heat transfer in the oceans), but even if you were, it doesn’t change that considering the change in temperature in the whole ocean ignores that most of the warming is happening near the surface. If the transfer to the deep ocean is slow (or negligible) then it would imply a high TCR-to-ECS ratio (i.e., we’d reach equilibrium very quickly). I think that even the OHC measurements we have so far largely precludes this possibility.

  40. Mitch says:

    There seems to be some confusion here about ocean mixing–the mixing is occurring where deep water is forming–off Greenland and around Antarctica, so reflect temperatures there. The oceans mix by being stirred, about 1/3 by tides and 2/3 by winds. The mixing lifts the existing deep water back to the surface to be replaced by new water. Otherwise, the warm water would stay on top and the deep ocean would stagnate, and grow anoxic. The geochemistry of sediments shows that the mixing has been sufficient to keep the deep ocean oxic for the last 65 million years, including some very large temperature transients. Given a long enough time, the deep ocean will warm.

  41. Mitch,

    The geochemistry of sediments shows that the mixing has been sufficient to keep the deep ocean oxic for the last 65 million years, including some very large temperature transients.

    Interesting point, I hadn’t heard this before.

    Given a long enough time, the deep ocean will warm.

    That was my understanding.

  42. Olof R says:

    Regarding OHC, I do a calculation based on data from Argo Marine atlas (Argo only) which has data through December now. It is a simple model based on global average temp for seven layers, and the global water volumes and average physical properties for each layer.
    It starts in 2007 when the Argo array was fully deployed (It didn’ track NOAA- Levitus OHC very well before that). The chart also has modelled TOA imbalance data, assuming that 93 % goes to the ocean, and 15% of that goes deeper than 2000 m. I only use 12 -month running means due to residual seasonality in the OHC anomalies

    The Argo-only data is three months ahead of NOAA/NODC. The OHC peaked with the 12 month period ending in March, fell seven months through October, but have been rising again in Nov and Dec. Basically, only the waters above 1000 m showed this recent dip in OHC. The OHC in the 1000-2000 layer has increased continuosly but slowly through 2016.

  43. JCH says:

    4th quarter NODC OHC is in… OHC 0 to 2000 meters went back up.

    Oolf R – great stuff.

    https://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/

  44. angech says:

    anoilman says: January 24, 2017 at 5:02 pm
    ” there has been no evidence that the science of global warming is wrong. None nadda zippo.”
    Step 1 – Extra water vapor CO2 causes warming of the atmosphere and surface
    Extra CO2 causes warming of the atmosphere and surface.
    plus small amounts of other GHG.
    I agree with you on Step 1.
    Step 2 – Feedbacks, did we forget feedbacks? While not “wrong” I do not think the science has got the feedbacks right.

    “There is not alternative theory for the planet to heat up… none nadda zippo.”

    There are Milankovitch cycles and differing ideas on the heat of the sun in the long term, and others.

    You presumably mean as a general rule for this planet with an atmosphere and you do ignore confounding factors,
    There is albedo change, you might agree to that.
    This can be due to clouds from a number of different sources, Air pollution from forest fires and volcanoes. Vegetation growth color changes and extent, Plankton, coral sporing.We might be coming out of a time of high cloud cover. Those are minor alternative theories and may well explain some of the natural variability.
    GHG’s, all of them, are still the primary driver of this earth’s temperature at this distance set from this sun, yes. I agree with you.

  45. angech says:

    JCH says: “4th quarter NODC OHC is in… OHC 0 to 2000 meters went back up.”
    Did I detect a hint of worry? Surely not. Might help bump the GMST up.

  46. angech,

    There are Milankovitch cycles and differing ideas on the heat of the sun in the long term, and others.

    Milankovitch cycles rely on the same physics that we think applies today and there is increasing evidence that there isn’t some additional – as yet not understood – impact from the Sun.

  47. BBD says:

    There are Milankovitch cycles

    Orbital forcing peaked ~12ka and has declined slowly ever since to a near minimum now. Based on the effects of orbital forcing, we should be *cooling* not warming abruptly. You’ve mentioned this before and been corrected on it so no idea why you are bringing it up again. Please take notes if your memory is failing you.

  48. BBD says:

    TE

    And, the warmer the deep ocean might get, the more readily those waters are displaced by near freezing waters created at the poles.

    Zachos et al. (2001):

    The Deep-Sea Stable Isotope Record

    As a framework for this review, oxygen and carbon isotope data for bottom-dwelling, deep-sea foraminifera from over 40 DSDP and ODP sites representing various intervals of the Cenozoic were culled from the literature and compiled into a single global deep-sea isotope record (Fig. 2)

    Which revealed that (my emphasis):

    The most prominent of the climatic aberrations is the Late Paleocene Thermal Maximum (LPTM), which occurred at 55 Ma near the Paleocene/Eocene (P/E) boundary. This event is characterized by a 5° to 6°C rise in deep-sea temperature (>1.0‰ negative isotope excursion) in less than 10 ky (Fig. 5) (25, 26, 73).

    But nothing deterred, here’s you:

    There probably are knowledge gaps wrt oceans which we’re all too ready to fill with speculation.

  49. Andrew Dodds says:

    Note that there are two potential modes of ocean circulation – the current one, driven by the formation of very cold water at the poles (notable, cold, saline water because of the freezing of sea ice), and warm-haline circulation, driven by salinity differences – where areas of high evaporation form pools of high salinity, which then sink. We see the latter today in the Mediterranean outflow into the North Atlantic.

    At the moment the oceans are dominated by polar deep water formation, but this does not have to be so. Remove ice formation and heat the poles, and you’ll get more influence of warn, saline waters in the circulation, which will among other things warm the deep oceans significantly.

  50. Olof R says:

    JCH, I have updated my OHC chart with Quarter 4 data from NODC. Here is a live link:
    https://drive.google.com/open?id=0B_dL1shkWewaSkJBNk43Si1xSlU

    The NODC OHC 12 month running mean is still decreasing despite the new data. The OHC of 4th Quarter 2016 was actually lower than that of 4th quarter 2015.
    One could also say that the quarterly resolution of NODC isn’t fine enough to catch the recent two month uptick, in contrast to my Argo-only calculation with monthly resolution.

  51. verytallguy says:

    On the thermohaline circulation. I think it’s rather out of date, but I doubt the fundamentals have changed.

    http://www.pik-potsdam.de/~stefan/thc_fact_sheet.html

    “What drives the THC?

    The short answer would be: high-latitude cooling. In cold regions the highest surface water densities are reached, this causes convective mixing and sinking of deep water, which drives the circulation. ”

    “More likely than a breakdown of the THC, which only occurs in very pessimistic scenarios, is a weakening of the THC by 20-50%, as simulated by many coupled climate models ([28]).”

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s