There is no mention in the paper of latent heat from the melting of Arctic sea ice. Moreover, it seems that the rise in heat content has paused since the year 2000 BCE. Could this pause be due to the thinning of the Arctic sea ice causing the additional heat to be absorbed by the latent heat of melting ice?
Sorry if this is slightly off topic, I am surprised that there is no mention on this website, or related ones, of http://data.giss.nasa.gov/gistemp/graphs/ showing that the global mean temperature for April set new records, and with it the January-through-April average for 2010. Isn’t this newsworthy? We have had quite high global temperatures for a while, but now we are breaking records again, aren’t we?
The last prolonged La Nina episode “fully coupled” with the atmosphere was AMJ 1973 –MAM 1976: Over 30 years ago….A significant amount of warming is natural, how about we split it 50-50 (fair enough?).
[Response: Oddly enough attribution is not done by assertion, or even fairness. But more on that another time. – gavin]
Sorry this is off topic, email from Climate 411, the Environmental Defense Fund , has alerted me to the American Power Act. Everybody should hear about this because it does not follow Jim Hansen’s formula. Information on the Act is at http://www.piie.com/publications/pb/pb10-12.pdf
I would enact what Jim Hansen prescribed in “Storms of My Grandchildren” exactly or stronger. See: http://www.komanoff.net/fossil/CTC_Carbon_Tax_Model.xls The American Power Act does everything but. If the American Power Act is enacted, we would still get 16.8 quadrillion BTUs of energy from coal in 2030. That would surely continue warming the oceans. Call your senators every day.
Comment by Edward Greisch — 21 May 2010 @ 10:14 PM
MSNBC covered this yesterday, w/coauthor Gregory Johnson. Two remarkable things about the interview: the personality handling the piece never once mentioned rejectionists and Dr. Johnson managed to twice convey to the audience an excellent thumbnail descriptor of the ocean’s role in our climate, namely that it is “the flywheel of Earth’s climate system.”
Flywheel. That’s a marvelously intuitive yet physically reasonable way to put it.
What, if any, effect on global temperatures 1s the Iceland volcano likely to yield?
[Response: Given the activity to date, no detectable effect at all. First, emissions into the troposphere get washed out quickly, and second, the emissions of SO2 (which create sulphate aerosols) have been very small – some 3 orders of magnitude less than pinatubo for instance. The elements that are bad for planes are not what impacts climate, and vice versa. -gavin]
I am looking at the referenced indirectly http://www.nodc.noaa.gov/cgi-bin/OC5/3M_HEAT/showfig.pl
which shows 2009 sea surface temperatures. I guess it means that most of the ocean surface temperatures are something like 3.5 degrees C warmer than before. Is that correct? That is a lot.
[Response: Not sure where you get that from- the figure is for data distribution, not temperature. -gavin]
I am impressed that they were able to add up the data and make the calculation. There is a mountain of data, but it seems to be rather difficult to deal with. It seems to be sort of a “fuzzy” data set.
Comment by Edward Greisch — 22 May 2010 @ 12:28 AM
Edward Greisch @ 10:14 pm, thank you for providing the link for the American Power Act. I’m very active in politics and can tell you that the forces driving the US towards further coal consumption (energy density of coal, domestic supply, labor employment, big-business/mining concerns etc.etc.) are essentially insurmountable. It drives me mad, but I’m hard-pressed to suggest alternatives.
Imagine turning off your laptops for 23 hours/day, restricting your LCD TV and other electronic media….would any/all of you posters be so willing? We are all in this together, and yet I don’t sense any real appetite for sacrifice from Democrat (protect labor payrolls), Republican (protect industries), or otherwise.
*sigh* the Earth will be a nice place for insects in about 50 years or so.
Great link to the key resources. It is critical to read the Trenberth article and commentary, to fully appreciate the Ocean Warming work published and what remains to be done. It is hardly good news whether you are an ice shelf or a coral reef.
In regard to heat sinks, you note that sinks of “…melting ice, are much smaller, and can be neglected in the main..”
I would have thought that the Greenland and Antarctic ice sheets and even the 20,300 cubic kilometres of floating ice in the Arctic would have been quite significant sinks. Since 1980 the Arctic has lost almost 14,000 cubic kilometres of ice; thats warmed up to zeroC, then melted. That’s a lot of Joules gone someplace other than the atmosphere! http://psc.apl.washington.edu/ArcticSeaiceVolume/IceVolume.php
Since full melt of all grounded ice is equal to over 70 metres of sea level rise, then it follows that there is the equivalent volume of 70 metres of ocean surface that is currently existing as ice at less than zero C. If your measurements of ocean heat content find most of the heating occurring in the top few hundred metres, then this equivalent volume of water-as-ice looks like an important proportion of the total ‘ocean’ sink. Yet its ‘discounted’ as able to be largely neglected?
Its not just the melting, but the ongoing increase in ice temperature with depth that demands a lot of heat input. Are there any systematic measurements of deep ice temperatures in Greenland or Antarctica that give any indication of the actual change in energy content of all that ice, outside what is needed to crack the latent heat of freezing?
Gavin, I am sure many (most?) of your readers have also read the recent public exchanges between Roger Pielke Sr., Kevin Trenberth, Roy Spencer and Josh Willis. As far as I can tell, this RealClimate post today completely contradicts what Willis and Pielke both agreed, and it seems very strange to this reader that there is no mention or reference here to any of it. Do you have any comments for those readers who have seen the exchanges I refer to? Best, Alex
[Response: Trenberth is interested in being able to say precisely where the energy flows are going on relatively short timescales – this is hard because the accuracy in the year to year numbers is not very good and so there is a lot of wiggle room. Everyone would rather this not be the case, but with the current measurement system, these year-to-year uncertainties will persist for a while longer. Over the longer term the accuracy is better, there is less wiggle room, and in fact we are able to balance out the energy flows – i.e. the increase in ocean heat content is pretty much what is expected from the anticipated radiative imbalance (see the figure). Perhaps you could be more precise about what you think is contradictory? – gavin]
17 CRS: There is no reason to go without electricity. Again read “Storms of My Grandchildren.” I agree with Dr. Hansen and President Obama that we have unlimited safe clean cheap nuclear power available as well as large amounts of wind, solar and geothermal depending on geography. The only real problems are the $100 Billion cashflow of the coal industry, the $1 Trillion cashflow of the total fossil fuel industry and people who object to nuclear for reasons unknown to me. Please, I am not trying to start another interminable debate. Please argue with Hansen and Obama on nuclear. Both industry [except the fossil fuel industry] and labor can easily be protected and benefitted by a change in energy source. The economy as a whole can grow because of the changes in energy sources. The fossil fuel stockholders would be better off to sell out sooner rather than later, but they refuse. It is CO2, not energy use that we are fighting. The American Power Bill shows that we have made progress. Keep calling your senators.
The units used to measure heat content on the graph are in 10^22 Joules. It would be helpful if this could be converted to more familiar units, such as watts per square meter required to generated this much heat, or the number of degrees Celsius this will raise the water temperature.
By the way, I am pleased to see two science postings in a row!
Obviously the deep ocean >700 meters is the most difficult place to sample temperature changes (and to drill for oil). If you have good measurements of upper ocean and atmospheric temperatures, then if you had a good decade-long satellite record of the Earth’s total radiative energy balance from space – say, if Triana has been launched to in the late 1990s – then you could use conservation of energy to calculate the rate of heat uptake by the deep ocean over the past ten years. Since this satellite wasn’t launched – the fossil fuel lobby managed to block funding for Triana with some political assistance – you’d instead have to rely on the stitched-together records of near-Earth satellites.
Even so, many of the difficulties involved in processing existing satellite data have been resolved, for example:
Fu et al. Enhanced Mid-Latitude Tropospheric Warming in Satellite Measurements, Science 2006
The spatial distribution of tropospheric and stratospheric temperature trends for 1979 to 2005 was examined, based on radiances from satellite-borne microwave sounding units that were processed with state-of-the-art retrieval algorithms. We found that relative to the global-mean trends of the respective layers, both hemispheres have experienced enhanced tropospheric warming and stratospheric cooling in the 15 to 45° latitude belt, which is a pattern indicative of a widening of the tropical circulation and a poleward shift of the tropospheric jet streams and their associated subtropical dry zones. This distinctive spatial pattern in the trends appears to be a robust feature of this 27-year record.
This is in direct contrast to the previous claims of media skeptics like Sallie Baliunas (July 2005)
Simulations of the enhanced greenhouse effect forecast a warming trend of approximately 0.25 to 0.35º C per decade, or accelerated warming compared to the surface. The well-validated temperature of the low troposphere shows a significantly smaller trend, +0.077º C per decade.
In fact, Fu et al. report tropospheric mean rates of +0.20 K per decade, as well as stratospheric cooling of -0.33K per decade, well within the ranges predicted by global climate models forced with fossil fuel emissions and ozone changes.
Sallie Baliunas was so surprised by this result that she threw in the towel and declared that the skeptic’s argument no longer holds much weight. Furthermore, she said, “In 1999 we pointed out that, quote, ‘When tested against the Arctic temperature record… the computer forecasts are seen to exaggerate the projected warming by a large amount.’ Obviously, we were wrong about that, too. Rational scientists can no longer support that position.”
Mr. Dowden, I think I have the conversion from Joules to degrees Celcius for the scale, but corrections to my math are very welcome for my hasty calculations.
My approach was to convert joules into calories and then apply that to the volume of the ocean.
I converted the measureable scale span into calories.
Then Cubic area of oceans (cubic KM) to milliliters.
Finally, milliliters divided by calories.
The numbers worked out like this:
2×10(23) (measurable scale) x 4.184 (calories per Joule, which is also what is required to raise 1 ml of water one degree celcius) = 8.37×10(23) calories.
1.33×10(9) cubic KM volume of oceans = 1.33×10(24) liters (gotta love the way metrics is synched for measurements)
1.33×10(24) milliliters of ocean water divided by 8.37×10(23) (total calories) = 1.59 degrees celcius for the entire measureable scale.
Loads of problems with my calculation – let’s consider it a rough thumbnail. First, the study measured the top 700 meters, so using the entire volume could make the whole thing hopelessly wrong. Second, I relied on the good old Internet for ocean volume, so that might be wrong, invalidating it. And third, I’m a bit rusty and might have used some Jethro Clampett “Cyphering” on the math.
At any rate, the big thing is that there is a helluvalot of energy getting absorbed into the ocean.
Can freshening of the polar oceans have sufficiently increased (but been inadequately measured) so that down welling is reduced, and therefore the deep ocean is hiding a pause in its warming?
The best estimates of sea level rise would be insensitive to such a change – except for the very small non-linearity of the density of sea water with temperature. And that might account for the small anomaly between SLR and upper ocean heat content for the last decade?
Re Toppy – assuming the equilibrium climate (as measured by global average surface temperature) doesn’t shift with ENSO, a La Nina should actually cause a gain in heat. My understanding is that ENSO changes the global average surface temperature by vertically rearranging the heat in the ocean. By exposing colder water over a larger area of the surface, a La Nina would cause a radiative imbalance that leads to some heat gain. An El Nino would have the opposite effect. The positive feedbacks reduce the imbalance in that case, but they would prolong the time it would take for the global average surface temperature to return to equilibrium if the La Nina or El Nino were permanent.
Blair Dowden, I am not a climate expert, but here is my read of these papers regarding your question of how 10^22 J/yr compares using other measurement units:
Please read both the paper and Dr. Trenberth’s commentary in the same issue of Nature; then go read this Trenberth paper (which Gavin also linked). Trenberth uses a pretty good comparison to heat released by burning fossil fuels: “Human activities contribute directly to local warming through burning of fossil fuels, thereby adding heat, estimated globally to be about 4 x
Trenberth’s paper says: “Human activities contribute directly to local warming through the burning of fossil fuels, thereby adding heat, estimated globally to be about 4 x 10^20 J/yr …” So the unit of 10^22 J/yr is about 25 times all the heat released from fossil fuel combustion.
In the Lyman et. al. paper, they say:
“Accounting for multiple sources of uncertainty, a composite of several OHCA curves using different XBT bias corrections still yields a statistically significant linear warming trend for 1993–2008 of 0.64 W m-2 (calculated for the Earth’s entire surface area), with a 90-per-cent confidence interval of 0.53–0.75 W m-2.”
Given the trend in OHC from the Lyman graph is slightly less than 1 X 10^22 J/yr, then we can compare the yearly trend of 0.64 W m-2 to get an idea how OHC compares to the planetary energy budget.
I find that Trenberth’s commentary is necessary to understand the Lyman et. al. results in comparison with other data. Trenberth shows (Figure 1) a quick and dirty comparison of the Lyman trend versus the data from a previous study of Argo data down to 2000 m, instead of the 750 m data used in Lyman. This data from Argo from a fairly short period of 2003 to 2008, shows a trend of 0.54 W m-2. Here is Trenberth’s comment:
“The warming ocean is revealed by changes in heat content from 1993 to 2008, shown by the black line with error bars, as constructed by Lyman et al.1. This analysis samples the ocean to 700 m depth and gives an average warming trend of 0.64 W m−2 (red line). The data available from Argo floats since 2003 enable an estimate to 2,000 m depth (blue line)8 to be made. The differences between the black and blue plots after 2003 suggest that there has been significant warming below 700 m, and that rates of warming have slowed in recent years. Processing of the two data sets is not compatible, however, so firm conclusions cannot yet be drawn by comparing them.”
This seems to show that a significant amount of heat is ending up in the deeper ocean.
Another issue that seems to be problematic; the recent flattening in OHC seems inconsistent with SLR, which currently is close to the long term trend. I don’t think that increased ice sheet melt can explain the difference.
It will be interesting to see if the Argo data show areas where significant amounts of heated water is being pushed down into the ocean. Perhaps the delivery of heated water into the deeper ocean is spatially distributed in a highly irregular pattern. Clearly we don’t have enough information on how heat is being absorbed into the ocean heat sink.
24 Edward: Thanks for the conversation!
[edit – OT]
And, just try to take coal away from politicians of any stripe from a producing state!! Illinois is having a coal renaissance, our high-sulfur coal is cheap and popular….utilities can scrub the sulfur out of the off-gas for less money than higher-cost Wyoming low-sulfur coal. The Democratic party is in lock-step with union forces, and won’t be turned back.
*sigh* It will be easier to deal with the chemical and geoengineering aspects of carbon mitigation (I’ve done this work under the Kyoto CDM) than with the political forces!! Don’t forget, even if the USA halted all coal consumption, we would have to deal with China and India etc. It is damn frustrating, I share Dr. Hansen’s feelings.
I feel like I want to write a sequel book “Arthropod Plagues of our Grandchildren.” At least insects are high in protein….
Trenberth’s article is a good example of an honest assessment of the state of climate science, and the limitations of the data and our understanding thereof. It doesn’t alter the Bayesian prior that increased CO2 is likely to cause warming to be upfront about the limitations of our understanding or of our data gathering status. It is the opposite of what we have come to understand about other segments of the climate science culture, both in its honesty and realization that humans will adapt whatever actually transpires.
9000000 km^2 Arctic sea ice melt spring – summer
1.8e+13 m^3 at a 2m average thickness – this is generous – see http://psc.apl.washington.edu/ArcticSeaiceVolume/IceVolume.php
917 kg/m^3 for ice
0.143 percent going into ice melt spring – summer; BUT, a roughly equal amount comes back out during the refreeze in the fall – winter; and since it’s floating, it doesn’t effect sea level.
BTW, I have been known to miscount decimal places, so I wouldn’t bet a large amount that these numbers aren’t off by a factor of ten – YMMV, and one[Alistair & Nigel] would learn a lot by checking these estimates with other numbers – e.g. the TOA insolation is ~344 W/m^2; starting there, do my numbers still make sense? If you Google the best estimates of runoff +thermal expansion contributions to sea level, and assume that the none thermal expansion part came from permanent ice melt, do you get similar volume numbers?
“Oddly enough attribution is not done by assertion, or even fairness. But more on that another time. – gavin”
But computer models are entirely built on assertions, no? You may argue that those assertions are justified, but the model itself is not the actual system.
The post says “if there has been more energy coming in at the top than is leaving, then it has to have been going somewhere “. And another comment of yours says: “the increase in ocean heat content is pretty much what is expected from the anticipated radiative imbalance “.
Both implying that there has been no actual measurement of the actual radiative imbalance. I had a long discussion on this forum several months ago regarding the ability to directly measure radiative imbalance from outside the atmosphere, and no one seemed particularly interested in it. Any papers on this that you could point to?
What sort of temperature rise in deep ocean basins would be sufficient to destabilise clathrates? Does anyone know?
I wish I could remember where I read it, but I seem to remember that the margins of methane clathrate deposits are more or less at equilibrium w/regard to their response to temperature and pressure which of course completely figures. That being the case, I suppose any change in temperature or pressure conditions will cause a change in the location of the margins. Presumably a larger change will cause a larger movement of margins and a more rapid change will trigger a more rapid movement of clathrate margins.
Sort of the same deal with ice; it’s automatically adjusted to prevalent conditions and hence quite sensitive to changes.
Re: 38: says
“Trenberth’s article is a good example of an honest assessment of the state of climate science, and the limitations of the data and our understanding thereof”
and then goes on also to say
“It is the opposite of what we have come to understand about other segments of the climate science culture, both in its honesty and realization that humans will adapt whatever actually transpires.”
Well, we can all read into Trenberth what we wish, but let me quote what he actually says.
“Given that global warming is unequivocally happening
 and there has so far been a failure to outline,
let alone implement, global plans to mitigate the warming,
then adapting to the climate change is an imperative.
We will of course adapt to climate change. The question
is the extent to which the adaptation is planned and
orderly with minimal disruption and loss of life, or
whether it is unplanned?”
It seems to me that Trenberth is not particularly more sanguine than “other segments” about the prospects. That conclusion is based not just on this article but also on other things he has written.
In any case, the article is not at all about just how alarmed we should be. It is rather a call for resolving uncertainties to help us better cope with climate change.
Mike G (40) — You can find the phase diagrams of pressure versus temperature for clathrae stability and compare those to temperatures at various depths. Somewhere there is a graphic of that. Briefly, the only (moderately substantial) clathrate dissolutions are in/near the Arctic Ocean at shallow depths. The vast majority of the methane released remains in the ocean.
Of greater conern are the resevoirs of methane in wetlands and permafrost.
Comment by David B. Benson — 22 May 2010 @ 4:50 PM
#9 – #11: OK, I’m glad it wasn’t a secret anymore. :) However 1 blog post and a few comments by Kevin himself here and there isn’t a lot of coverage. Probably most here take it for granted that temps are rising. It seems that only a complete record year, with a confirming result from CRU, would count.
Looking at the (Gistemp) graphs, as a non-expert, it doesn’t seem that records can easily be broken by “weather” alone, and recently we are consistently close to record temps. Perhaps not enough to convince those who believe everything is a result of urban and arctic heat islands, but I think enough of a signal to send to those who are not following the graphs by habit, but occasionally stop by, trying to find out what the facts are.
Back to topic, or at least closer:
Apparently, in the years around 2001-2002, there was a very steep increase of ocean heat as measured. The time span after 2003 doesn’t seem that unusual if one considers the possibility that the high values around 2003, and the low values shortly before the 2001-2002 period, have been “weather” rather than “climate” and are obscuring the underlying continued upward trend.
Again, (speaking as someone occasionally stopping by), these articles highlight that the quality of the models are not the bottleneck of research, but the acquisition of measurement data. Which, in turn, I would guess, is mostly a question of financial resources. However, it doesn’t seem that climate research is already consuming huge amounts of resources, so I wonder whether the resources are not increasing as one would expect, or whether this is just not being discussed in public, or whether I just missed it due to the specific limited reading I do.
I read somewhere that NASA recently was able to start using 2 drones for atmospheric measurements. But what about increasing the number of arctic measurement stations, as apparently the mismatch between NASA and CRU results indicates a lack of data here, and what about the question of whether the uncertainties in this article about ocean heating could be resolved by improving resources. (BTW, what about measuring the temperature of the ice, rather than just whether it melts or not, don’t know if that makes sense).
The authors obviously wish for better measurement data, but it doesn’t become clear (to someone like me) whether technically solutions are ready to improve the situation, if financial resources were available, and whether any financial investment could be expected to be spent well in technically effective ways. I’m sure these questions are discussed elsewhere, but it doesn’t become clear to me here in this context.
Thanks Brian Dodge 39! Useful reassurance. The only bit you appear to ignore is the heating of the ice up to zero. But since the latent heat requirement is a lot more than the warming requirement, it is likely is it not that that figure would be similarly low % of the global insolation. Thanks again; I’ll pull that one worry bead off my necklace! N
If the measured Global Sea Surface Temperatures as measure by AMSR-E since 2003 vary between +2 C and – 2.5 C, and the trend has demonstrated a slight decline, whom should we believe? The models which report a continuing increase? Lyman et al 2010 who adjust the raw data for an extrapolated result? or consider a pie-in-the sky speculation that the “missing” heat now resides in deeper and as yet unmeasured oceans? This article cries out for an editor to say “show me the beef.” The article has none, just mouthing words. Sad, sad sad.
[Response: What’s sad is the continual jumping from one source of data to another, from one start date to another and for ever less significant time-periods in a desperate attempt to demonstrate to yourself that the planet is not warming. It is. Get used to it. – gavin]
Mr. Benson, where can I find a frostline/treeline map, and if there’s been a measureable change in them.
To be honest, its something I’ve been waiting to read about. If the tundra is slowly giving way to the boreal forest it will be the “in your face” sort of symptom of global warming that is far more convincing than a weather event.
Oh, and did anyone check my math in the scale conversion? I’m gonna relook it, as I think I may have misplaced a decimal point. 1.6 degrees celcius seems to be too large for the range of temperature increase.
I don’t know how accurate 510 million km2 is for Earth’s surface area; taking 4*pi*6371^2 km2 ~= 510.064 million km2; but I don’t know the formula for an ellipsoid (polar radius is slightly smaller than equatorial radius)(for what it’s worth, 4*pi*6381^2 km2 ~= 511.667 million km2, which gives a sense of why most of the mass of the atmosphere can be approximated as having the same horizontal area as at sea level (a 1 % increase in area is reached at a height of about 31.8 km)).
37 CRS: Average coal contains 1 or 2 ppm uranium. Illinois coal contains up to 103 parts per million uranium. A 1000 megawatt coal fired power plant burns 4 million tons of carbon per year. Coal is 25% to 96% carbon. That multiplies out to 412 tons of uranium in the cinders and ash [Illinois worst coal] plus 14.7 million tons of CO2 per 1000 megawatts per year. 3% of the fly ash gets into the air. The cinders have to be trucked away. If you can’t convince them on the CO2, work on the psychological angles. See: http://www.ornl.gov/ORNLReview/rev26-34/text/coalmain.html
for other pollutants in coal, such as thorium, lead and arsenic. Licking the GW problem is going to take a lot of psychology, marketing, and other skills. Tell the truck drivers who haul the ash that it contains uranium, thorium, arsenic, lead, etc. Unburned coal contains Benzene and benzene is an extremely strong carcinogen. Tell that to the miners. Shaft [underground] mines also have radon, the radioactive gas, in them because radon is a decay product of uranium. The higher the percentage of uranium in the coal, the more radon is in the mine air. Illinois coal miners may be in violation of the standards for radiation workers. Radon decays in about a day into polonium, the super-poison. If I had your email address, I would send some analysis sheets for several mines. If you could visit some union chiefs and slip them the information it could help. Get help wherever you can.
As far as India and China are concerned: That argument has been used before, and it is bogus. China and India will fall in line as soon as the US does because China and India are already on the edge of famine and the situation in both is getting worse. Remember, all that 10 to the 23rd power joules of heat in the ocean is causing the wind to blow the wrong way over India and China and everywhere else. Agriculture is suffering in many more places than it is benefitting. The comments on the previous post on this web site have a lot of discussion on floods and droughts. Both are happening to farms in many places and both curtail food production. The problem is all that excess heat in the ocean, of course.
GeoEngineering: The popular GeoEngineering solution is to put SO2 into the stratosphere. The problem is that SO2 is a poison gas. SO2 + H2O=H2SO3
H2SO3+O=H2SO4=sulfuric acid=battery acid. If it forms in your lungs, your lungs dissolve. The best and cheapest thing to do is to make it illegal to take coal, oil shale and tar sands out of the ground.
Good luck, agent 37. :) :)
Comment by Edward Greisch — 22 May 2010 @ 10:33 PM
Very ‘a propos’ Gavin. We know that sea ice doesn’t necessarily form when outside air temperatures are just below zero, for instance Eastern sea board is largely ice free during the coldest of winter. I also know that Arctic sea ice starts forming with about -11 C air temperatures, when its especially not windy. This is the current Arctic balance of sea ice formation. When the ocean warms further, this balance likely means that sea ice onset will start at even colder temperatures, with the warming atmosphere this will make a refreeze of the Arctic Ocean well into the long night. From the get go, at current Arctic warming rates,
we have less than 20 years before the Arctic pack ice becomes seasonal like Antarctica. But if the sea warms further, as it does relentlessly, just like the atmosphere, may be in a few years there will be hardly any second year ice. Even so, most in this world worry not about a dark blue North Pole, each coming summer brings us closer to a different planet seen from space, may be most have never thought about simply this look.
Whenever there are revisions made to estimations and/or projections of quantities such as ocean heat content…..why, oh why is it always in the direction of “things are worse than we expected”? Unlike many here, I will actually be around to see the ramifications….
Norbert: if you include both land and sea temperatures combined then we are likely to see consecutive records broken month in-month out from now on until there is a large prolonged trend in land/air temps the other way which at the momenmt seems increasingly unlikely.
Still for March and April 2010 land temps were I think 8th hottest on record and 15th respectively or something around there…so we are not fluctuating to anywhere near normal range on the ‘troughs’. Every year that the air temps are near record highs it will push ocean temps that little higher and that’s not withstanding the affects of ice albedo either. It seems to me the comb. land/sea temps are taking more of an exponential curve and the natural variabilty is getting narrower as well.
Comment by Lawrence Coleman — 22 May 2010 @ 11:58 PM
Gavin: I read that the land of iceland and greenland is measurably moving upward as the ice sheets that have been compressing the land are melting and thus getting lighter….my question..could the recent eruption of Eyjafjallajökull have been triggered by slight changes in the tectonic forces in the area caused by the progressive loss of ice thickness?
[Response: Not as far as I know. – gavin]
[Response: Actually, there is some literature on this sort of thing. In fact, the release of stresses following ice unloading are significant enough to matter. There is evidence, for example, that Mt. Rainier experienced this following the last glacial maximum, as the large glaciers retreated from it’s flanks. This doesn’t in any way suggest one can meaningfully attribute the eruption of Eyjafjallajökull to ice unloading though. At best, it is a contributing factor to the exact timing – i.e. at the scale of “this month, rather than next year”. This is one of those straw-the-broke-the camels back sort of things.–eric]
Comment by Lawrence Coleman — 23 May 2010 @ 12:06 AM
Does anyone have the formula to calculate the ocean heat content from temperature data. I am looking at ARGO data for the Indian Ocean basin. The raw temperature data show a significant (from 2003 to present) decline in ocean temperature in the upper 700m.
I would like to convert the temperature data to heat content.
Comment by Richard Steckis — 23 May 2010 @ 12:13 AM
On being more specific about what seems contradictory about this piece and the Pielke/Trenberth/Willis (PTW) exchange, I suppose, as a non scientist, it seems to me that the conclusion at the end of PTW is that the measurements of OHC seem to be completely contradictory to model predictions, whereas this present RealClimate post has the opposite conclusion, namely, that measurements perfectly confirm the model predictions.
There were others at the time, i.e. follow ups by Roy Spencer, and Pielke Jr., but this was the one that really grabbed my attention.
It is my impression that Willis completely agrees with Pielke whilst politely disagreeing with Trenberth (et al) throughout that exchange.
But, if what RealClimate has posted here is true, it would be unfortunate that by completely ignoring this recent blog exchange, RealClimate has given the impression of burying its head in the sand and throwing inconvenient analyses under the rug. Because you make no mention of this exchange, a reader like myself who is unable to crunch the numbers himself is free to simply choose the one he likes best. And I have to admit that I do like the Pielke/Willis view better.
So wouldn’t it be good to comment on where you disagree with Pielke/Willis?
[Response: That conversation is talking about closing the budget for very short time periods – which everyone acknowledges is not well constrained due to the uncertainties in the radiation flux calculations and the OHC measures. For the long term changes, the numbers have tracked model estimates (Hansen et al, 2005; Domingues et al, 2008) and continue to do so (see above). Differences in analyses for short periods are large, and I have been consistent in stating that they are too large for dramatic conclusions to be drawn. – gavin]
It is largely because science is conservative and errs on the side of moderation.
Keep that in mind when some ignorant fool claims that scientists are being sensational in their statements.
Comment by Vendicar Decarian — 23 May 2010 @ 1:03 AM
Whenever there are revisions made to estimations and/or projections of quantities such as ocean heat content…..why, oh why is it always in the direction of “things are worse than we expected”?
It cuts both ways. Hansen 88’s, climate sensitivity has been reduced by about 25% (~4C down to ~3C for double atmospheric CO2). GISS adjustments result in a lower centennial temp trend than raw for global surface stations, and lower for the last 50 and 30 years than raw. I guess we don’t hear much about that sort of thing, but it’s there for anyone to look up. Global sea level and Arctic sea ice projections appear to have been underestimated (IPCC AR4). This is less to do with revision of data and more with recent observations (the data is processed, of course), but care must be taken when trying to prognosticate from short-term trends.
54 Ed: We think alike! I’ve been bitching/moaning about the radionuclide burden of coal since the 1970’s. Nobody seems to care…it’s a non-issue except to a handful of folks like on this blog.
When I was Sr. Env. Scientist to the Gas Technology Institute, we disparagingly referred to coal as “the fuel that won’t go away.” That’s just the way it is, we have to find some way around the problem. I’m working on it as we speak….if we can’t regulate/legislate coal out of existence, we have to make it economically unattractive and offer better alternatives. After all, we don’t burn wood/dried cow pies for fuel as much as we used to!
Have faith, everyone. Kate 56, I hear you! Some of the brightest minds are working on these problems right now, you will hear a flood of news (patent announcements mostly) in the coming months.
so, everyone knowing CO2 blocks a band of IR no other gas blocks believed the missing heat went into oceans and this had to be confirmed by sizing it up. and as CO2 is a part of carbon cycle, the fast component of which is enzymatically driven (by plants) and obeys (most of the time (during summer days)) Michaelis-Menten kinetics and gives a similar non-linear response that is harder to prove than a linear one. looks like the acceleration has started and i’m thinking will anthropocene be like pliocene or early miocene-paleocene.
Frank Giger, thanks for the calculation. You have the relationship between calories and joules inverted. I would rather work with yearly figures, which reading from the graph is about 10^22 joules per year. This is my calculation:
10^22 Joules x 0.24 Calories/Joule = 2.4 x 10^21 Calories
1.3 x 10^9 km^3 of ocean x 10^15 ml / km^3 = 1.3 x 10^24 ml of ocean.
But we are working with the top 700 m of ocean. Given an average depth of 3790 meters, we get
1.3 x 10^24 ml x 700 m / 3790 m = 2.4 x 10^23 ml of ocean.
2.4 x 10^21 Calories
—————————– = 1.0 x 10^-2 degrees
2.4 x 10^23 ml ocean
By this calculation, the top layer of the ocean is gaining one hundredth of a degree per year. That seems too low. Can someone show what I am doing wrong, if anything?
What’s sad is the continual jumping from one source of data to another, from one start date to another and for ever less significant time-periods in a desperate attempt to demonstrate to yourself that the planet is not warming. It is. Get used to it. – gavin
A very succinct and accurate assessment of the entire AGW denial culture.
Comment by Pete Dunkelberg — 23 May 2010 @ 8:51 AM
68: the average surface temp increase is a couple of tenths of a degree C per decade. Your 700M number of .01C/year is about half that. Since the oceans are warming more slowly than the land this sounds about right. If you had dropped a decimal point I don’t think the agreement would be that close.
Hmmm… with the understanding that news has roughly the same relationship to data (i.e., history), that weather has to climate, I ask Mr. Benson @45 (/et alia/):
“Briefly, the only (moderately substantial) clathrate dissolutions are in/near the Arctic Ocean at shallow depths. The vast majority of the methane released remains in the ocean.”
That would appear not to be the case – or do I misunderstand the relative quantities of methane being released into the ocean (Gulf of Mexico) by the British Petroleum (BP) Deepwater Horizon/oil volcano there? One to two million gallons per day of stuff (oil+gas), at pressure. Even with a 50/50 breakdown (low), that’s a *lot* of methane.
And yes, BP’s lack of transparency /in re/ those quantities makes this all somewhat difficult. Hopefully that lack will change quickly, and already is, but:
What *is* this oil spill likely doing to the Gulf, purely in terms of methane? How much goes in before a practical saturation point is reached?
What are people not asking, that they ought to be – strictly as this spill might affect AGW generally (ocean heat-uptake specifically?)? I am not asking about the biology of the situation – those answers are unfortunately more clear – just about what long-term physical processes we may have unleashed (and cannot, apparently, stop) which relate to Global Warming.
I dunno. Maybe it’s a dumb question, and the quantities involved are small and irrelevant. It doesn’t seem that way though.
Comment by Jaime Frontero — 23 May 2010 @ 10:41 AM
By the way – in reference to my previous post; I note that the oceans of the world *emit* about 15.5 million tons of methane per year – and that the Arctic Ocean itself (an area of considerable and increasing concern) accounts for half of that. This would be as reported, March of this year, by “…an international research team led by University of Alaska Fairbanks scientists Natalia Shakhova and Igor Semiletov.”
I have been wondering about the interannual variability in the OHC data.
Is this thought to be a real variability in OHC or is it thought to be mostly due to the not so good accuracy in the year to year numbers ( as Gavin hinted in response to #21)?
Are there single drivers big enough to explain this variability?
Jaime Frontero – Escaping methane in the Gulf is being examined. One consideration might be the fact that some/much of the exiting methane may be forming clathrates as it hits the cold water as demonstrated by the [foolishly unanticipated?] problem using the containment dome.
Blair Dowden (68) at quick glance I think the volume of the top 700m of the sphere is more than your 700/3790 ratio would say; though that aggravates not helps your problem. Maybe there’s something else.
where H is in Joules, m the mass of the object in question, cp the specific heat capacity at constant pressure, and T the absolute temperature. I would divide the ocean into horizontal layers with different mean pressures and temperatures and figure it that way. You might try a model using lapse rates and see if your total converges as you try more and more thinner and thinner layers, calculus-style.
The main problem is that you are assuming thermodynamic equilibrium, which would certainly not hold for such a short period. You need to take into account the time required for a temperature anomaly to diffuse downward. This would require dividing the ocean into a minimum of two layers and solving a partial differential equation (the “heat equation”)with appropriate boundary conditions.
I’m visiting a friend who’s a radio host, and I’m sitting in on the show tomorrow morning. The special guest is “a monkey who can predict the weather better than NOAA”
I googled it, it’s a publicity stunt by the Center For Public Policy. The chimp is “Dr. Hansimian”, and by having him randomly roll dice or whatever, he can predict hurricanes just as well as NOAA. This supposedly disproves climate change, I guess.
I’m a mere art major with no climate expertise, but I do have a healthy skeptic streak, and I smell a rat. What can I bring to the table tomorrow morning?
Bypass the chimp and go directly for the issue of what sort of policy improvement can be expected from a think tank generating sophomoric cheap shots. So, drill in on “How did you choose a name for your ape stuntman?” Don’t let it go.
Barton Paul Levenson says:
23 May 2010 at 4:33 PM
heat content H = m cp T”
Thanks Barton for the formula and analysis advice.
Comment by Richard Steckis — 23 May 2010 @ 10:51 PM
Kaje, with all due respect, I think it would be a mistake to engage the monkey people in argument. They’ll come with a bag of well honed arguments which will sound like science and which will only be effectively debunked by someone with a firm grasp of the science. IMO the fact that they stoop to this kind of stunt is potentially more illuminating to your listeners than a failed attempt to discredit them. Res ipsa loquitur.
76 flxible: Please keep us posted on the air analysis over the gulf oil spill. Altitude, distance and wind need to be reported along with substances found.
Does anybody have a graph of the methane coming out of the oceans over many years? How does what is coming out now relate to 50 or 100 years ago?
Comment by Edward Greisch — 24 May 2010 @ 12:33 AM
Gavin (or anyone else in the know),
Can the NODC data in recent years (since circa 2003) be trusted? I think that Richard’s question @30 is an important one, especially since (as far as I know) the NODC site is the only place where one can obtain OHC data which are updated regularly.
Unfortunately, Lyman et al. do not shed any light on why the NODC data are so much lower, and in fact showing a short-term decline whereas the other data (from Lyman et al.) are not. The NODC revised their OHC estimates down earlier this year, but provide no explanation on the site.
Anyhow, an explanation as to why the data sets differ and which one is more trustworthy (Lyman et al’s vs. NODC) would be very much appreciated.
[Response: The difference is in the corrections to the XBT data, which is obviously part of the systematic error. Lyman shows that these issues make a difference in the transition period to the Argo floats mainly. Thus the NODC numbers should still be useful as long as this uncertainty is acknowledged. I imagine that Levitus et al are trying to improve their analysis on an ongoing basis and they will be working on the best approach to the issue. -gavin]
“Doesn’t surprise me. Weather is chaotic and is predicted by weathermen. Climate is statistical and is predicted by actual scientists. When you can understand how a ca sino makes a consistent profit, despite the fact that you can’t predict any individual hand of blac kjack or spin of the roul ette wheel, you’ll understand the difference between weather and climate–and why your stunt does nothing to disprove global warming.”
I am still left with the impression that you are evading the question of the meaning and significance of the Pielke/Willis/Trenberth exchange.
We all know, of course, Trenberth’s now famous behind the scenes remark that it is a travesty that we can’t account for the lack of recent global warming, and his exclamation that the observing system must be inadequate (which I guess is reference to the satellite radiation budget measurements?). Trenberth later claimed that there is heat missing and that it must lie beneath >700m in the deep ocean and that it may come back “to haunt us”. But Willis then agreed with Pielke that it is probably impossible and that it’s unlikely we’ll find any missing heat below 700m. Pielke Jr spelt it out for us the next day that this means the “missing heat” is probably missing because it has been radiated out into space, or in layman’s terms, because it’s just not there.
Now a few weeks later we find ocean heat has been adjusted upwards by Lyman et al. and we find Josh Willis one of the coauthors. Yet Willis already agreed that he thought the existing measurements were pretty good. Pielke has used Willis’s data to show a decline in OHC since 2003 which doesn’t appear in this the new Lyman et al analysis. (In fact, it looks like Willis has frankly got his own name on two of the curves in your diagram, both the NODC data and the Lyman et al data. Is that right?)
So what is the conclusion for this? There is missing heat below 700M or there isn’t?
[Response: There is clearly some heating going on below 700m. But this discussion of ‘missing’ heat is very confused. The satellite records are not good enough to say what the year-to-year imbalance is and so are not able to say whether any heat is missing or not. So what is the ‘missing’ idea based on? Model estimates – but as I showed above, the estimates of OHC change are in line with the models, and so I don’t see why anyone thinks that any heat is missing. If the satellite data were better, there might be something to this, but right now the issues are all in the noise, and thus pretty unresolvable. – gavin]
On monkeys predicting hurricanes: it’s a funny stunt, and nothing more. It’s an old gag with a different punchline. Over the years we’ve seen horses that predict weather by stomping hooves, pigeons that predict the stock market by pecking on stock listings, etc. If birds were really consistent and better than people at forecasting stocks we wouldn’t have stock brokers as such; we’d have bird keepers.
The best counter isn’t a counter at all. It’s a laugh at it along with tales of similar stunts, and then a big “so what.”
Let’s say a magical monkey could predict the number of hurricanes in a given season accurately. To be honest, whup-de-do. It’s nice information, but not critical – and easily trained, since we know roughly the number of hurricanes each year due to the cyclic nature of their appearance.
Where hurricanes are forming, their track and intensity is actually more relevant. And for that I’ll trust the trained metorologists over Bubbles.
A Category 3 hurricane isn’t a big deal in the scheme of hurricanes, until they hit the wrong spot. Brush the coast as it peters out and not much damage. Hit the shore over a city that is built in a bowl that is below sea level with a levee system plagued by 30 years of mis-management and its a disaster.
It’s worth noting that there are still some lingering instrumentation issues w/the later equipment. Here’s a synopsis of troubles leading to the present:
“In 2003, it was found that problems with the Druck Pressure Sensor were causing some floats to stay at the surface for prolonged periods and eventually to become surface drifters. The Druck Pressure Sensor is the successor to the Paine pressure sensor in Seabird CTDs. Even when not severe, the problem may have caused errors in the salinity measurement due to increased biofouling due to prolonged surface exposure. When the problem was found, the CTDs were recalled and the source of the problem was fixed, but this was not possible for floats already deployed. A large number of SOLO floats with FSI CTD packages deployed in the Atlantic Ocean between 2003 and 2006 were found to have a pressure offset problem due to a software error. This error caused pressures to be paired with the temperature measurements from the next lower level, creating the illusion of a cooling ocean. Once the problem was found, a list of such floats was compiled. An effort was made to correct the problem, successful in some floats, not in others. All data from all these problem floats are included in WOD09. For those data which could not be corrected, all float cycles are flagged. More recently, in early 2009, a problem with the Druck pressure sensor has been found (J. Willis and D. Roemmich, minutes of 10th meeting of International Argo Steering Team). This problem causes pressure sensor drift after deployment. Deployment of new floats was halted temporarily, until the pressure sensor design could be altered. Already deployed APEX floats are being monitored closely for sensor drift. The full extent of this problem is not yet apparent”
81: Jerry Stevens said: You need the heat equation and diffusion.
I don’t agree. Diffusion is not how heat gets buried in the ocean. If it were the top of the ocean would be hot and the depths would never get heated. The diffusion time for heat in water is L^2/D with D~=10^-5 m^2/s. Thus for heat to diffuse 1000m takes 10^11 seconds ~=10^4 years. Simply considering the time it takes to heat up the water a given amount with a given heat flux is far more telling, which basically assumes that the transport is instantaneous.
If you really want to consider thermal transport you need a model of the velocity field. People write down heat equations for the ocean but then they pretend that they’re not really talking about molecular heat transfer but some sort of effective heat transfer so they use much larger thermal diffusion coefficients than the molecular ones. Then you have to pick a thermal diffusion coefficient out of your … hat and argue for the value you chose. There are cases in which folks have derived “effective” diffusion coefficients for particular hydrodynamic flows but there is no rote procedure for doing this. I would argue that you either can assume instantaneous transport or you use an ocean model and advect the heat away. I believe that if you check you’ll find the two give roughly the same answer.
Comment by John E. Pearson — 24 May 2010 @ 9:56 AM
You can predict the next day’s weather with about 75% accuracy (in temperate zones) by merely saying “same as today”.
Skill with weather models increases that to 85%. However, that is quite significant if you’re looking for the prediction horizon (where you’ve got a 50-50 chance). With continuity, your prediction horizon is less than 3 days. At 85% you can extend it to over 4 days (more, because the skill is in asserting change, therefore the 85% is not completely independent).
Therefore a monkey randomly bashing away gets it WORSE than the even LESS clever “same ol’ same ol'”.
Comment by Completely Fed Up — 24 May 2010 @ 10:13 AM
99: Jerry, I accidentally misspelled your name “Stevens” when it should have been “Steffens.” sorry about that.
Comment by John E. Pearson — 24 May 2010 @ 10:22 AM
> World Ocean Database
great link, thank you Doug Bostrom.
Good clear explanation for people who want to understand how science gets good results from instruments and cross-checks and calibrates them.
Also from that same doc: “There are no significant identified problems with the temperature sensors. Oka and Ando (2004) found no drift in temperature from 3 recovered floats after 6-9 months. They did find significant error in one of the three recovered conductivity cells (~ -0.02), from a PROVOR float, showing again the relatively larger problems with the salinity measurements from profiling floats compared to temperature measurements.”
If folks want to make a contribution to understanding of OHC measurements and in particular if they want to formulate a useful and progressive critique of Lyman et al they’re going to need to read and comprehend the entire document as well as reach a level of expertise equaling or exceeding that of Lyman and his coauthors. Failing that investment of effort, critics will need the assistance of a miracle in order to do better.
Open Ocean Buoys have been found with water sitting in the humidity sensor.
One reason why “WE DEMAND THE RAW DATA” is asinine. You need far more than the data to make the raw data usable.
Comment by Completely Fed Up — 24 May 2010 @ 12:30 PM
Is there any place that the full report can be found without having to purchase a copy? I only ask because some reports are available this way and I don’t know if this is.
Comment by David Davidovics — 24 May 2010 @ 1:15 PM
“That would appear not to be the case – or do I misunderstand the relative quantities of methane being released into the ocean ” Jaime Frontero — 23 May 2010 @ 10:41 AM
1 ton = ~7.3 barrels oil
estimated Gulf oil leakage rate ~21600 barrels/day(5-40,000 depending on who’s estimating) or 3000 tons/day
methane emission = 1.5e3 ton/day = 1.5e9 g/day at 50% methane by weight in the leak(probably a high estimate)
Gulf area = 1.5e6 km^2 = 1.5e12 m^2
Gulf average depth = 1.62e3 m
Gulf volume = ~2.4e15 m^3
“Figure 8 shows data collected while working with hydrate mounds or with pieces of hydrate. Methane concentrations rise from a background level of ~0.1 µmols/l to a high of ~8.8 µmols/l.” http://www.nrl.navy.mil/research/nrl-review/2002/chem-biochem-research/coffin/
This indicates to me that the upper limit of CH4 concentration is about 10 µmols/l where the temperature and pressure allow formation of clathrates.
1µmol CH4 = 1.6e-5g/l = 1.6e-2 g/m^3
1.5e9 g/day/2.4e15 m^3 = ~6.3e-7 g/m^3/day = ~2.5e-6 micromolar increase per day diluted over the volume of the Gulf, However, given the 80 fold variation in concentrations observed above under much milder conditions, and the observations of clathrate formation at the wellhead, there are undoubtedly plumes of near methane saturated water(with volumes orders of magnitude less than that of the Gulf) drifting in the currents, slowly dissipating by diffusion and biogeochemical oxidation.
There are probably “blooms” of methanotrophs where the concentrations are high, and mixed populations of microbes of wildly varing composition across the methane/oxygen/temperature gradients.
According to wikipedia clathrate “… observed density is around 0.9 g/cm³. One liter of methane clathrate solid would therefore contain, on average, 168 liters of methane gas (at STP)” so the formation of clathrates near the wellhead would buoyantly transport the gas to near surface layers above the clathrate stability zone, where it would break down into bubbles and dissolve; I think that turbulence in the rising column would disperse the clathrate and bubbles widely enough that little if any would make it directly to the surface. Estimating how rapidly and how much of the Methane would diffuse into the air before being oxidized is beyond my abilities.
Methane, (plus ethane, propane, butane, etc) is also being transported dissolved in the oil that is reaching the surface – I wonder if BP is flaring off the vapor from the oil they are capturing?
The ~1.5e3 tons/day is probably not currently significant in comparison to the ~1.5e7 tons/year ocean emissions; it’s a good bet that the significant consequences will be environmental, economic, and political. The secondary effects on climate through these areas could be larger – if the Gulf seafood industry(40% of US total?) collapses, that will (in a very inequitable process) reduce fossil energy consumption and emissions in that sector. Every cloud may have a silver lining, but that is of faint comfort to those who freeze their butts off in the rain.
Re @93. Thanks. As you know, some contrarians/deniers are capitalizing on the fact that the recently adjusted NODC 0-700m OHC data have shown a small negative slope since 2003 or so (yes, it is not a stat. sig. slope, but we know that does not matter to them). In contrast, the 0-2000 m in Lyman et al show a positive slope over the same period. So my real question is whether or not the negative slope in the NODC data circa 2003 is real or not, or if it is an artifact of measurement/processing errors. It would be nice to have someone from NODC here to explain what happened and why their curves are at odds with those of Lyman et al.
I’m inclined to go with Lyman et al’s. data, because they have gone to great lengths to correct the data and it is documented in their paper and Trenberth notes that their numbers have been independently validated, whereas NODC provide no explanation of why they adjusted their numbers downwards earlier this year and is a near-real time product without all the corrections being made.
Gavin said, “The difference is in the corrections to the XBT data, which is obviosly part of the systematic error. Lyman shows that these issues make a difference in the transition period to the Argo floats mainly.”
I’m missing something. The period most affected by Lyman et al is the present. Are XBTs used at all anymore in the calculation?
Which of course speaks to the utter bankruptcy of the “Center for Public Policy” with regard to producing any useful input to public policy. That’s why any dialog with the knuckle-dragging chimp-handlers should entirely focus on their choice of a moniker for their hapless prop, how it reflects on their seriousness of purpose, skipping the whole probability issue.
Why a troupe of Howler monkeys should be allowed in charge of a chimp is another question entirely. I feel sorry for the chimpanzee.
Off Topic: The recent Smith Megafauna paper in Nature Geoscience is being widely quoted in the media as being a possible explanation for the Younger Dryas cooling: the key paragraph in the paper appears to be:
The concentration of methane both influences and is influenced by temperature, but lead–lag and indirect relationships are not well characterized13. Ice-core records from Greenland suggest that the methane concentration change associated with a 1 °C temperature shift ranges from 10 to 30 ppbv, with a long- term mean of about 20 ppbv (ref. 13). Thus, empirically, the 185 to 245 ppbv methane drop observed at the Younger Dryas stadial is associated with a temperature shift of 9 to 12 °C. The attribution and magnitude
of the Younger Dryas temperature shift, however, remain unclear. Nevertheless, our calculations suggest that decreased methane emissions caused by the extinction of the New World megafauna could have played a role in the Younger Dryas cooling event.
The rest of the communication seems to be high quality, but this paragraph is frankly somewhat stunning: it includes all the right caveats (lead-lag relationships, attribution remains unclear) but the extrapolation of a 245 ppb CH4 drop to a 9 to 12 degree C temperature change, caveats notwithstanding, seems to me to be without justification. The 1 degree to 20 ppb relationship is almost certainly mainly in the direction temperature to methane, and not vice versa (yes, its a feedback, so it is really both ways). Not to mention that CO2 and N2O also covary with methane, so even if the entire temperature change was based on GHG changes and not orbital changes, CH4 would contribute less than half… My back of the envelope calculations suggests a forcing change of less than 0.2 W/m2 from a drop of 245 ppb – even at the upper end of the CS range this would contribute only about half a degree C to cooling…
Would this be appropriate for a short realclimate piece on scientist communication with the media (though in this case, because the statement appears in the actual text of the paper, the media isn’t really at fault at all)?
Re 111 Patrik – that could be a difficult number to derive because you need to select a baseline. What would qualify as zero heat – everything in solid form at 0 K, perhaps, but if we’re going to include the latent heat of liquifying and freezing the air, why not also include the latent heat of chemical reactions, assuming chemical equilibria are reached… etc. Then we could also discuss converting all atomic nuclei to some isotope of Fe… (?) I think it’s much easier to use anomalies. It’s a relatively simple matter to determine the change in enthalpy if some liquid water at one temperature changes to liquid water at another temperature or ice or vapor at some other temperature, etc.
So was the methane build up because of all the rotting carcasses or human farts from a meat enriched diet?
Oh, I’m sorry I misread. Apparently the drop in methane was caused by a lack of farts from ice age megafauna…
Comment by Rattus Norvegicus — 24 May 2010 @ 9:12 PM
If anyone tuned in after my hype, I apologize. Dude didn’t even mention climate change; it was all about dissing NOAA’s hurricane predictions. I wanted to ask if his free market- fellating org supported the Civil Rights Act, but I couldn’t get a word in edgewise. A real letdown.
re. #107 Chris Winter- “Dr. James Hansimian.”
re. #121 Kaje
I must admit, it takes an intellectually depraved simian like mentality to produce that level of rubbish, par for the course.
This simple fact that ‘Kaje’ of whom stated “I’m a mere art major with no climate expertise, but I do have a healthy skeptic streak”
is invited to speak publicly on the subject of climate as stated, “visiting a friend who’s a radio host, and I’m sitting in on the show tomorrow morning.”
to give context to a side show carnival type stunt being presented as a challenge to the scientific community is utterly ridiculous. Can anyone spot the strawman? To impugn the body of science, the scientific method and Dr. James Hansen in such manner is beyond childish, it is truly pathetic.
Furthermore, one would think one would ask a climate expert to discuss climate, or at least someone well versed in the science rather than the, as stated, ‘skeptic side’ obviously without scientific basis and of dubious bias.
Regardless of Kaje’s perspective on the matter or the fact that they did not mention climate change. It is a complete red herring/strawman to say that NOAA is not perfect, therefore science is monkey business.
This speaks volumes about the lack of scientific perspective being used by the denialst side. They have been reduced to cheap parlor tricks to present their argument.
The video is produced, according to the credit, by
‘The National Center for Public Policy Research’
501 Capitol Court, NE #200 Washington, DC 2002
Tel. (202)543-4110 http://www.nationalcenter.org
Bill O’Reilly could not resist participation in the completely ludicrous media stunt which basically puts him in pinhead status when it comes to scientific method. But hey, whatever sells commercials and pleases those willing to drop down to simian status.
so, the upper ocean heat content is increasing and the polar front is getting more turbulent. what does this mean to the thickness of the so called multi-year ice? the avalanche studies tell us the layers formed in the snow are indicative of the type of avalanche expected, is there any reason not to believe that so called fractured multiyear ice won’t behave in the same style (breaks laterally)? given the salinity anomalies in the arctic ocean at http://bulletin.mercator-ocean.fr/html/welcome_en.jsp is there any reason not to believe that the saltier water penetrates the so called multi-year ice at these yearly layers or the water line of the floes? is the salinity due atlantic water or is it possible that this is indicative of the methane clathrates and the salts within them? what again was the maximum thickness of one-year ice (i recall some measurement of 230cm)? is the multi-year ice reaching these levels? is there any reason to believe multi-year ice seals the fractures in it during a winter? I think the currents from Bering sea will spread the remaining ice so the decrease in extent will slow down shortly, but that it will speed up again in about three weeks. why was august generally warmer than may, again? sorry for this inquisitive post, but some might like to find these out, and i too lack a clear picture of some of them. yours jyyh.
You are quite right that the journalism behind the Felissa Smith et al. piece was just as sloppy as the actual paper behind methane’s role concerning the Younger Dryas (as is their argument for why the “anthropocene” should be expanded backwards in time). In this case I would say it is the Nature authors to blame, although I’m not sure it is worthy of a RC piece, and I suspect the paper itself will be relatively low impact. Neither the authors themselves, nor the media reports, seem to have been able to come to grips with distinguishing between Greenland temperature anomalies vs. global temperatures. In fact the global temperature changes relatively little at the Younger Dryas due to the bipolar seesaw effect from a reduction in the AMOC. The media reports vastly overstate the sensitivity to a less than 200 ppb change in methane, and Greenland has a lot more things going on than just CH4 during the YD. I have no idea what was happening with the Nature reviewers, but at least this part of the piece should not have gotten past review.
Thank you for that work. My calculations aren’t so far off though – if typically less elegant – but we start in different places.
The estimates of leakage I find to be credible are in the range of 100 – 200 kbbl/day (of ‘stuff’). And I’ve seen (but don’t pursue) gas/crude ratios as high as 80%. We’ll skip the gas/crude ratio part of it though: leave it at your 50%.
But… at ~200 kbbl/day (rather than the ~21.6 kbbl you used – and yes, that is admittedly high; but not as high, I believe, as 21k is low) we wind up with roughly 1.5e*4* ton/day methane. Or, x365, ~5.5e6 ton/year. Still at your 50% gas/crude ratio. Yes?
Compared to the methane output from all the world’s oceans, of 1.5e7 tons/year, that does strike me as a significant number. I hope I’ve screwed up somewhere there.
That can’t be right, can it? I’d rather be embarrassed.
Comment by Jaime Frontero — 25 May 2010 @ 12:33 AM
If I may put my hand up again Learned Sirs! We have a series of heat sinks here. First is cold old ice in ice sheets; well below zero C. Not mobile, so the heat has to get to it by some mechanism, mainly conduction.
Then we have latent head of freezing in place on grounded and floating ice. Again heat gets into this ice by conduction.
Next we have water where the movement of the water shifts the energy around by convection and induced horizontal movements etc.
Finally we have the atmosphere where again convection and horizontal movements allow the energy to be shifted around.
My impression of heat sinks in systems where there are a series of sinks at different temperatures is that ideally they try to operate isothermally. That is, the system’s energy increases by warming the coldest bit first, and when that is up to temp then the next sink starts to warm with it, etc. So in this case the coldest ice is the prime target of the heating effort, then latent heat sinks then ocean and finally atmosphere.
Obviously in real world the rate of transport of energy from hot places to cold places (wind and current) is a factor in the rate at which each sink takes up heat. But I would have though that the atmosphere and at a slightly slower rate the ocean would be pumping as much heat as they can into ice (warm up and latent heat) until most of the ice is up to ocean temperature. Thus it seems likely that the ice is really getting hammered by the Earth’s thermal imbalance, and if that’s so then all issues related to warming ice are looking like getting worse before they get better.
“First is cold old ice in ice sheets; well below zero C. Not mobile, so the heat has to get to it by some mechanism, mainly conduction.”
Just a wee note: the Arctic is called “The Land of the Midnight Sun” for a reason.
Comment by Completely Fed Up — 25 May 2010 @ 7:44 AM
> Baliunas …. throw in the towel
I hope Ike comes back to identify where that came from. I suspect he was paraphrasing; quotation marks made it appear it was a quote, but they do have other uses. I’d guess he was recalling a Tim Ball editorial very widely rebunked; you can find the quote “Sallie suddenly and politely withdrew from the fray.” Typical Ball conspiracy theory stuff.
John P. Reisman (OSS Foundation) says:
24 May 2010 at 10:17 PM
“This speaks volumes about the lack of scientific perspective being used by the denialist side. They have been reduced to cheap parlor tricks to present their argument.”
Words fail. Logic fail. Science fail. The denialists seem hell-bent to give stupid & crass newer and deeper levels of meaning. This video & campaign were obviously produced by tiny little minds for tiny little minds. Perhaps they could upgrade their attack by bringing Jerry Springer or the Black Knight (because he always triumphs) aboard as corporate spokesmen to add credibility.
Comment by Daniel the Yooper — 25 May 2010 @ 8:15 AM
A couple of comments-
The ocean heat content measurements(change in water temperature) are temperature measurements, similar to the atmospheric ones. They appear to behave similarly to the atmospheric measurements so they most likely are not “stationary” in the statistical sense. It is not appropriate to use a linear curve fit to the data for such short time periods.
Just looking at the graph of OHC at 700 nmeters, the most obvious feature is the change between ~1998 and ~2004(also in the NOAA graphs), which corresponds to the time period with the largest measurement uncertainty in the Lyman et.al. paper and the changeover from XBT probes to the Argo bouys. Admittedly the data is very erratic(Lyman “but the underlying uncertainties in ocean warming are unclear, limiting our ability to assess closure of sea-level budgets”) (Trenberth “the messy data on upper-ocean heat content for 1993–2008 provides clear evidence for warming. But differences among various analyses and inconsistencies with other indicators merit… “). The conclusions in Lyman aren’t “robust” when the error range(up to 2.5 degC on a measurement range of ~8 deg C) is a large fraction of the measurement. It’s robust in the sense that every measurement technique shows an increase in temperature, but the wide range in results makes any measurement estimate very imprecise.
[Response: Where are you getting these units? The graph is in 10^22 Joules – and 10^22 Joules is equal to 10^22/(4180*0.7*5.1*10^14*700*1030) ~= 0.01 deg C on average over 700 meters of sea water. – gavin]
The step change from the 1970-2000 data and 2005-2010 looks really problematical. Take out the step(~7 deg C) and the so-called trend drops from 11 deg.decade(the spurious orange dotted line from 1995 to 2009) to ~1.4 deg/decade, half of the overall apparent change of 3.5 deg/decade for 1970-2009.
So what is going on? Possibly the change from XBT to Argo apparently wasn’t calibrated and the data is thoroughly messed up. At least another 30 years of Argo measurements are needed to measure what is going on.
Possibly some physical mechanism in the ocean changed- changes in rate of upper and lower ocean turnover, changes in locations of the turnover, changes in ocean currents, changes in the atmosphere affecting how much and where radiation reaches the surface or changing the heat transfer to the ocean, etc. The ocean isn’t anywhere near thoroughly mixed.
Re 127 NigelW- Nigel, the oceans/atmosphere are certainly not isothermal, and the energy definitely does not go into the coldest areas first. Just touch the asphalt on a sunny day, or dip into Lake Superior in the middle of August. Ice that melts in the sun will stick around for days in the shade. The instantaneous temperatures are highly localized and variable.
The climate and all the weather are the result of the uneven transport of heat through the system. The transport is highly localized and greatly affected by local temperatures and interactions between virtually every variable you can imagine on scales from feet to hundreds of kilometers.
re: 122. In addition, that puerile video hits the denialist’s trifecta: personal insult (on Hansen), anti-science (amazingly flaunting scientific ignorance as if gross ignorance is a good thing), and anti-government (attacking a government agency, NOAA). All that was missing from the usual mantra was an attack on EPA/regulations.
> Possibly the change from XBT to Argo apparently wasn’t calibrated
Wrong. You’ve got links above to confirm the facts. Why would you speculate without reference to easily checked facts? Just to delay?
> At least another 30 years of Argo measurements are needed
“Delay is the deadliest form of denial.”
Nigel (127), you’re pretty much correct, except where you say that systems warm the coolest bits first. Because of the whole sphere on an axis thing, we should see warm places getting warmer first – there’s more sun hitting the equator to the tropical lines that can be trapped by Ye Olde Greenhouse Effect. That warmer water is then moved to colder areas by current (most effective and efficient manner).
We pay attention to the warming of the cool parts because of the obvious, blatantly observable ice pack as it melts, but corals in some parts of the world are getting hammered as well with water too warm to be tolerated. But coral is so finicky (loads of stuff can kill coral reefs), that it’s much safer to look at ice.
” Thus it seems likely that the ice is really getting hammered by the Earth’s thermal imbalance, and if that’s so then all issues related to warming ice are looking like getting worse before they get better.”
Dead on the money.
Thirty years ago territorial limits within the Artic Circle were limited to academics and largely philosophical debates. Today we find Canada reiterating it’s claim that Longitude extends perpendictular to their coast (and doesn’t curve to the pole) and the Russians intensely mapping and claiming that the continental shelf extends from their coast to the North Pole (one way to determine limits of territory). Both are pre-emptive measures for when the Polar ice cap is no more and can be exploited for minerals and navigation.
Heat the water around a cold landed place and it’ll warm up, too. The main watchword is Greenland, as it lays pretty close to the great Gulf Stream conveyor and holds a helluvalot of water tied up as ice. Melting floating ice doesn’t raise sea levels – it’s already accounted for – but melting and adding water from land does.
And huge thanks to all for fixing my maths. I was driving back from the store and did a face palm thinking about what I did wrong, only to be relieved that someone had caught my errors.
So what is going on? Possibly the change from XBT to Argo apparently wasn’t calibrated and the data is thoroughly messed up. At least another 30 years of Argo measurements are needed to measure what is going on.
Besides Hank’s comment noting that you are indulging yourself in pointless speculation, positing a question that remains unanswered purely as your own personal artifact in your own head, let’s establish one important point of agreement or disagreement.
Do you believe the difference in OHC reflected between the x-y origin of the graph and the end of the data presented is an error?
It was never intended for me to offer “expertise” on this guy in lieu of an actual expert. I took (or tried to take, but I couldn’t bring the subject up) that up by myself after I found out details about the guest. My original purpose there was to banter with the hosts for the day, and get Jewel’s autograph (her being the other guest).
I’ve since learned that the hosts themselves were planning to mock the guy, but it didn’t pan out that way. Also, it seems he was mainly invited to rip on NOAA, because the hosts crossed swords with them in the past. (NOAA got mad at them because they joked about putting bourbon in emergency kits.)
So the guy plugged his monkey, we never got around to making fun of his ideology, and Jewel ended up running late and I just gave her bunny ears in a picture instead. Which didn’t show up in the picture. Suckage.
While there is something called the Arctic amplification effect, it does not necessarily mean the Arctic ocean is warming faster. More related to the general parameter differences of the northern hemisphere.
The oceans overturn heat content through oceanic currents. I don’t know much about Arctic ocean currents, but I would venture they actually do mix with other oceans. Extent of interactions and heat exchange?
So the question does not have enough specificity or understanding in its base to know what it is asking.
No worries, I was trying merely to point out that if they are choosing art majors to discuss NOAA and the pathetic carnival media stunt id est hansimian, it shows how out of touch the debate really is from that end of the farm.
I think storage of heat via ice temperature change is generally ignored. For an ice sheep, responce of deeply buried ice temperature to surface temperatures would be expected to be very slow. Thermal conduction is too slow to penetrate more than a few meters in relevant timescales. Heat (or its lack) does get advected downwards in the accumulation zone of an ice sheep, as ice is gradually buried, and extension in the horizontal direction. In equilibrium the vertical ice velocity at the surface would be the same as the net accumulation rate (generally a few tens of centimenters per year), so AGW effects will not have had time to penetrate beyond maybe 10 or twenty meters depth. That leaves only meltwater penetration as a potential way to inject surface heat deep into the ice sheet. I think deep meltwater penetration only ocurrs where there is enough summer melting to form surface lakes, which can drain deeply (probably to the base). But only the edge areas of the greenland ice sheet are warm enough for this to ocurr. I think the total surface area involved is not so great as to have much impact of the planets total storage of heat. I don’t think it is well known how much meltwater refreezes in the glacier, versus how much escapes to the oceans. The antarctic is too cold for this mechanism to matter there. So again the areas/volumes involved are orders of magnitude smaller than of the oceans, so I don’t think the error of omission is significant.
As only the first few millimetres of the oceans at most absorb long wave radiation emitted by GHGs and it is unlikely that this layer stops evaporation of heat from the oceans how can GHGs influence oceanic heat storage directly? Isn’t the only mechanism for GHG heating through heating the atmosphere above the oceans?
At what point does winter sea ice not form is the essence of the question. This would require seemingly require the Arctic ocean to be warmer so that the pole would be kept ice free. It has happened at some point on the past where the continents poition and the ocean currents were similar to today. Antartica started to develop its glaciers 34 million years ago and the Arctic around 5? Any evidence of either poles being ice free or have seen serious ice degredation during this time. For example has the Arctic ever been sea ice free during the winter?
re:130. Whoops, my bad. I misread the units on the graph. Doesn’t make any difference to the discussion though. Whatever the units, an error of 2.5 out of ~8 is a very large degree of error.
The obvious offset in the data during the transition from XBT to Argo is a much more interesting and useful item to examine. Once you’ve established what the data really is then you can go on to deal with the actual heat content changes are.
Another point on this, the heat content is the change in temperature at particular points in the ocean. The publicly available abstract makes the point that the dominant effect was the choice of method for making adjustments(correcting biases) to the data. However, the major conclusions shown are about the change in heat content(temperature) estimates. The meat of the matter is why the different adjustment procedures don’t agree and if there is any way to get accurate enough temperature estimates to make useful estimates of the accumulated energy.
The phrase “Accounting for multiple sources of uncertainty, a composite of several OHCA curves using different XBT bias corrections” raises a red flag to me. Sounds very much like picking dates when calculating temperature trends.
[Response: You have misunderstood more than the units. The whole point of the paper was to investigate whether the different correction techniques made a difference to the underlying trend – and the answer is that they don’t very much. That is, warming of the oceans is robust to the differences in approach. This does not mean we know what the exact right approach to those corrections are – but it does mean that you can be more aware of what the impact of those uncertainties are. They matter for the year-to-year variability, but not the trend. This is the complete opposite of picking one set of corrections that you ‘like’ and just going with that. – gavin]
I think the question is one of “was there a time without a permenant ice pack” rather than “ice free.”
The answer is a tough one. We know that Antartica froze in the winter even in the late Jurrasic, forcing hibernation of the dinosaurs (if we’re to believe the exellent Walking With Dinosaurs series. ;) ).
I was thnking in the era more of when ice ages have occured and when there has been permenent ice at the poles. The planet developed permanent ice at the poles when GHG/C02 levels dropped low enough due to weathering when India met Asia or so the present level of knowledge appears to be telling us.
We are not going to avoif 450 ppmv of Co2 let alone the other GHG’s so we had better find out. Some stuff I have read over the years seemed to point to a lot less ice when CO2 levels were anything from 450 to 700.
Well, it isn’t ocean *heat* content, but relevant to climate science in various ways is this story, about quantifying the methane released by the Gulf blowout (roughly estimated at about 7.5 kilotons so far.)
assuming it is correct as asserted by Alastiar McDonald that the Arctic has lost 14,000 cubic kilometres of ice since 1980… (any reference anyone?)then the latent heat abosrbed from the ocean to melt it is is approximately 0.5 8 10^22 Joules so the heat content of the ocean would need to be adjusted upward to refect
t this gain in heat ( not temperature ) .. think its called enthalpy!
“wouldn’t the ocean heat/energy decrease with melting sea ice? Or am I missing the whole thing??”
If I shoot an IR laser at an ice cube and melt it in a glass of water, why would the melting of the ice from that IR energy have to come from the ocean too?
Comment by Completely Fed Up — 4 Jun 2010 @ 8:24 AM
CFU, I was asking about colin Aldridge’s post which didn’t refer to radiation.
Radiation absorbed in ice would do the same thing as you say. I’m not sure how realistic that is; Doesn’t the preponderance of polar sea ice melting come from ocean heat, not radiation? (Hmmm. Or rather is it the ocean the that causes most of the melting of only that ice that exceeds the norm???)
Did you know that the sun radiates the earth, Rod?
You see, without any new input of energy, what happens is that the water and ice reach an equilibrium. The water gets cooled by the near ice and the ice warmed, but they will reach 0C where H2O can be either water or ice.
Some of the water will freeze because it gives it’s energy to the ice and some of the ice will melt, taking heat from the water.
Melting the ice requires that more energy goes in.
Either by replacing the cold water with warmer water (ocean currents) or by the sun warming the ice and melting it.
If the sun is doing it, it has to do it with radiation. There’s no conduction or convection to do it across 93 million miles of vacuum.
“Doesn’t the preponderance of polar sea ice melting come from ocean heat, not radiation?”
Where do you think the ocean heat comes from? And why do you think it avoids ice?
Comment by Completely Fed Up — 4 Jun 2010 @ 12:54 PM
Gavin, Interesting post as usual. One explanation by oceanographers, such as Mojib Latif, to partly explain the increase in temperatures in the 90s is that of a net transfer of heat from the oceans to the atmosphere. From the Argo temperature probes, calculating vertical temperature gradients throughout the 700 m depth should be able to tell whether or not the heating is coming mostly from the surface (i.e. due to SW solar and LW radiation absorption in the top layers of the ocean) or from the ocean depth. Has the net heat transfer from the surface been calculated from the temperature profiles ? Why can’t the spatial distribution of the Argo probe temperatures inform us on where the heat is coming from or going to?
[Response: I think there is some more information to be derived from this data, but the regional information has bigger uncertainties, and more internal variability. -gavin]
Thanks for the reply Gavin. Although satellites can used for example to obtain spatial distribution of temperature, clouds, water vapour, aerosols in the atmosphere it appears much more difficult to measure the physical characteristics of the oceans for example the distribution of the optical depth of the particles in the oceans. The temperature distribution in the oceans has to be interpolated from the localized temperature readings of the Argo probes. In contrast, the surface temperatures (on land) can be measured more easily and the atmospheric temperatures can be measured also by satellites. It appears that our understanding of the dynamics of the oceans is much less than for the atmosphere. How do we know that the radiation absorption and emissivity of the oceans is not changing over multi-decadal scales which would affect the heat content of the oceans?
Actually, gavin is right about the column integrated ocean heat uptake, but if you’re interested in SST’s then yes….hurricanes do somewhat act as a vacuum cleaner. This video shows the time-evolution of the 2008 hurricane season with SST’s, and if are patient enough to watch you will see that cyclones passing by leave a trail of relatively cool surface temperatures. The first good example is at the right of the screen about 1:00 in. There’s a pronounced effect from one about 2:35 in to the video.
Interestingly, there’s a recent paper out which suggests that ocean heat uptake due to tropical cyclone upper ocean mixing has been significantly overestimated in the past, so it’ll be interesting to see how this develops in the community.
For a clarification of my previous comment, it does appear as a “vacuum cleaner” effect though the cooling mechanism is moreso associated with entrainment of colder water induced by vertical mixing rather than by air/sea heat loss
This is a really great website! lots of excellent and well sourced information!
The temperature of the oceans is an interesting one, and one that we don’t seem to know that much about unfortunately. We have lots of data on the surface temperatures and now even the top 700m of water or so, but there is so much energy storage in the deeper oceans that we unfortunately don’t know all that much about. I guess tho since the deep oceans take so long to turn over most of the warming of the last century would show up in the top 700m anyway.
I was reading about Roy Spencer, he believes that the climate sensitivity is not as large as we had originally thought, he says to account for recent warming we need to look at the oceans and the Pacific Decadal Oscillations. I’m not an oceanographer but the figure on his site ( http://www.drroyspencer.com/global-warming-background-articles/the-pacific-decadal-oscillation/ ) that shows El Nino and La Nina over the last 100 years appears to show a correlation between global temperature and a 30 year cycle of El Nino and La Nina. The figure shows a high around 1935, a low around 1960 and the latest high around the year 2000. Just wondering what more informed minds thought of him or his science? Or any comments about any of his interpretation of data?