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Philip Shehan at 18:32 PM on 1 February 2014Corrections to Curry's Erroneous Comments on Ocean Heating
While it is good to sea evidence that heat is indeed being taken up by the oceans, the “pause” in atmospheric temperatures is indeed a myth based on a poor understanding of statistics. Permit me to reproduce part of argument I posted at Jo Nova’s blog.
The first rule of statistics is make sure your sample size is big enough for your result to be meaningful.
"That is where end points come in. It’s not really the end points that matter as such, but the number of years between the endpoints, or how big the data set. That is why I harp on about short data sets. Because of the “noise”, relatively minor variations in temperatures between different data bases can lead to significant differences between linear fits for short time frames. With longer time frames the signal to noise ratio improves and there is good agreement between the linear fits.
When comparing the two satellite data bases UAH and RSS which began in 1979, the regression lines are quite different for 15 years but very similar since 1979.
But the real problem is not apparent from just looking at the regression lines. They do not show how the error margins blow out for short data sets.
http://www.skepticalscience.com/trend.php
For both the RSS and UAH data from 1979, there is a statistically significant warming trend.
UAH Trend: 0.138 ±0.070 °C/decade (2σ)
RSS Trend: 0.125 ±0.069 °C/decade (2σ)For data since 1999, the error margins are so large that it cannot be said with any confidence that the data shows warming, cooling or a pause.
UAH Trend: 0.146 ±0.212 °C/decade (2σ)
RSS Trend: 0.027 ±0.211 °C/decade (2σ)Although the linear regression line values are quite different, the error margins mean that there is considerable overlap between the 95% confidence limits so the two data sets are in fact in statistical agreement.
Returning to the matter of end points. If moving an end point by a single year makes a large difference to the trend line, it is a sure sign that your data set is too short and the results not statistically meaningful.
From 1999 UAH Trend: 0.146 ±0.212 °C/decade (2σ)
From 1998 UAH Trend: 0.060 ±0.223 °C/decade (2σ)Note again that the large error margins means the trends are statistically in agreement, but cannot tell whether the data shows a warming or cooling trend."
Moderator Response:[RH] Fixed links that were breaking page format.
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grindupBaker at 18:07 PM on 1 February 2014Warming oceans consistent with rising sea level & global energy imbalance
I think if it's handy to have a faux-factor for ocean heat gain %age then it's either from sea water melt/freeze temperature or the average ocean temperature during previous glaciation. Former makes sense because we live in a water-world and there's a big rift in the aspects of liquid vs solid water that's pertinent to us. Latter has some rationale. A species living on a liquid-cheese planet will think we're incompetent and don't know Absolute Zero, but that's their problem.
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Rob Painting at 17:58 PM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
Chriskoz - See the NODC data referred to in the blog post - specifically this data. I understand that the mid-range estimate for the Hiroshima bomb of 6.5x1013 joules is used in the Hiroshima widget. The oceans gained 2.463x1022 joules in 2013. Divide that by the Hiroshima estimate above = 378,923,076 joules. Divide by (31,536,000) seconds per year = 12.01 Hiroshima bombs per second. Near enough for our purposes.
Why the sudden escalation? Pass. However, as noted in my comment @7, three of the subtropical ocean gyres were very active during the year. The active wind-driven ocean circulation should have drawn down a lot of extra heat into the ocean via the subtropical gyres. The persistent upwelling of cold water in the eastern tropical Pacific would have reduced cloud cover there, via reduced oceanic evaporation, and thus allowed more of the sun's energy to enter the tropical ocean - this would have aided the ocean warming process, as generally the case when the tropical ocean is cooler-than-normal.
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grindupBaker at 17:49 PM on 1 February 2014How Increasing Carbon Dioxide Heats The Ocean
Me @ 55. Nuts! Penultimate sentence should end "pushes 0.0076 w/m**2 down from 1.441mm depth to 1,000m depth."
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grindupBaker at 17:43 PM on 1 February 2014How Increasing Carbon Dioxide Heats The Ocean
guinganbresil #34 I think you don't understand because your thermocline graph lacks the detail that's the entire topic of discussion, the ocean "skin" and "sub-skin" that's shown in the
posting, but without scales that might give a clearer picture of what is happening. Sample numbers below will make it clear, I'm quietly confident.
Minnett & Kaiser-Weiss GHRSST 12-Jan-2012 has a graph of ocean skin temperature variation. Here are my sample or average global ocean numbers, forced to give the Sun's 161
w/m**2 exiting but nonetheless illustrative as nearly as matters.
temperature:
1,000m depth temperature = 5C
thermal conductivity of seawater 0.58 W/mK
ocean-air interface = 17.000C
1.441mm depth temperature = 17.400C (the warmest spot in the ocean depth though the "few metres" of depth below it is only a miniscule bit colder, all warmed by Sun SWR)
this top 1.441mm depth is the "skin" and "sub-skin"
temperature gradient of top 1.441mm of ocean is 277.6 Celsius/metre
By conductivity, temperature gradient pushes 161.00 w/m**2 up from 1.441mm depth to ocean-air interface which precisely removes the Sun's 161 w/m**2 going into the top few metresdepth and leads to no ocean warming.
AGW increases downward LWR and air temperature directly above ocean with extreme rapidity of a few decdes, which warms ocean-air interface by 0.700C, so:
ocean-air interface = 17.700C
1.441mm depth temperature = 18.097C
temperature gradient of top 1.441mm of ocean is 275.5 Celsius/metre
By conductivity, temperature gradient pushes 159.79 w/m**2 up from 1.441mm depth to ocean-air interface which leaves 1.21 w/m**2 of the Sun's 161 w/m**2 going down into the oceanbelow and leads to ocean warming of 13.8 ZettaJoules / year (the billions of atomic bombs in sks widget). So, the difference of 0.003C in the warming over the top 1.441mm of ocean
causes ocean warming that is 7.5 times as fast as the average post-glaciation ocean heat gain that moved the ecosphere from an ice age with glaciers down to New York State and
today's climate and ecosphere warming that is 4.5 times as fast including all the "ice-age" glacier melt that happened.
If the 1.441mm depth had warmed by 0.700C same as the ocean-air interface then oceans would gain no heat, but the massive colder oceans below will only let 1.441mm depth warm
by 0.697C and only when the entire ocean has warmed by 0.700C in a few thousand years will it let that 1.441mm depth warm the final 0.003C and stop heat gain with 4,100 ZettaJoules
of heat having been added to the oceans, enough to melt 13,666,666 cubic kilometres of ice. Of course, that will never happen because the ocean-air interface is going to keep warming
with the +CO2 that will keep happening and it's all going to accelerate.
Temperature gradient from 1.441mm (18.097C) to 1,000m (5C) depth is 0.01310 Celsius/metre
By conductivity, temperature gradient pushes 0.0076 w/m**2 up from 1.441mm depth to ocean
This is only 0.6% of the actual heat transport of 1.21 w/m**2 because 99.4% is transported down by water circulation, mostly natural with shark & whales & krill helping a bit. -
chriskoz at 16:28 PM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
bjchi@11,
I concur.
Changes in temperature are opposite to the changes in radiative imbalance. Deniers would love us to spell out which effect is "worse" and then label us the exaggerating "extremists and alarmists" or accuse us of "conflicting story". Such accusations are of course baseless and ignorant rhetoric & based on flawed ethics.
AFA ethics are concerned, I think radiative imbalance is bigger problem than the observed dT. That's because dT is felt directly by those who would like to delay the action to reverse AGW prompting them to reconsider their stance. While radiative imbalance is not felt and the action to reverse AGW is likely to be pushed into the future among bogus statements by deniers: "global warming has stopped in last xxx years", in an attempt to escape from the responsibility of their own actions.
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chriskoz at 15:49 PM on 1 February 2014Warming oceans consistent with rising sea level & global energy imbalance
KR@22,
For your method of verifying the TOA imbalance changes, it's better to check the newer graph from AR5:
(yeah, I finally learned how to insert imgs!)
where you can see the A forcing increased in last 3 decades (1980-2011) by about 1W/m2 (2.29 - 1.25 = 1.04 is exact central estimate).
The increase in global surface temperature (land + ocean) for that period can be seen for example from NOAA. I estimate dT increased from 1980 to 2010 by about 0.4K. Given equilibrium climate sensitivity of 0.75K/Wm2, the amount of forcing neutralised by said dT is; 0.4*0.75 = 0.3W/m2.
Therfore, out of 1W/m2 forcing in last 3 decades reported by IPCC above, 0.7W/m2 was not neutralised by dT and stays as radiative imalance increase. That yield about 0.23W/m2/decade which is slightly lower than quoted figure (0.30) because we just calculated an average of last 3 decades. 0.30, as the boundary value of current, increasing forcing, seems consistent with our result.
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bjchip at 14:33 PM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
I think that the point John Wise is making needs to be given some prominence in any discussion of ocean "heat". That we should not expect that heat, as such, in that location, to have any substantive effect on climate... as it corresponds to fractions of a degree over the entirety of the ocean and has no effect on the energy balance.
(We do NOT however know if the heat is in fact evenly distributed down there. I'd guess it is NOT, simply based on the fact that it is not evenly distributed on the surface, so there may be risks to Clathrate formations we do not know about)
We should include it because some accuse us of hiding that issue. When it shifts back we will see even faster rises in temperature and while it continues we are getting a continuously worse imbalance built up. As Rob points out in his response.
Just saying.... it'd be good that we make sure everyone knows we are telling the whole story.
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chriskoz at 14:18 PM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
In this paragraph:
Long-term the oceans have been gaining heat at a rate equivalent to about 2 Hiroshima bombs per second, although this has increased over the last 16 or so years to around 4 per second. In 2013 ocean warming rapidly escalated, rising to a rate in excess of 12 Hiroshima bombs per second - over three times the recent trend
the part emphasised is unknown to me. Can you give more details why such sudden escalation in OHC and provide a reference?
Thanks, Chris.
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chriskoz at 13:55 PM on 1 February 2014Warming oceans consistent with rising sea level & global energy imbalance
scaddenp@16,
Celsjus scale is interval scale only. It is not ratio-scale because it does not have meaningful zero point, al least in relation to saltwater temperature, therefore you cannot use it to calculate a ratio.
So you cannot answer the question "by what percentage the oceans are warming" with "0.9%". There is no answer to this question because the question is ambiguous: it does not specify the relation with respect to what the "warming percentage" is sought.
If the question specified, e.g. relation to the molecular kinetic energy, then Kelvin scale (which has meaningful zero point in this case) would have been appropriate to calculate the ratio.
Read more for example here (Quantitative data).
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ubrew12 at 13:26 PM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
Rocketeer@1 said: "Easy calculation if I knew the mass of the ocean." I googled 'mass of the ocean'. Hope that helps.
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chriskoz at 13:03 PM on 1 February 2014Warming oceans consistent with rising sea level & global energy imbalance
Tom@20,
In your estimate you first assume:
assume that the forcing increases by 0.3 W/m^2 per decade
then, by deducting TCR of 2/3 of assumed forcing, to obtain TOA imbalnce increase, you conclude:
[...] the energy imbalance increases by 0.1 W/m^2 per decade [...] Given this, it is likely that the 0.3 W/m^2 figure quoted in the article is a mistake...
That conclusion came up as the result of your assumption, which is just your assumption not supported by any data. The quoted figure most likely comes from different assumption so I don't understand by what logic you can call it a "mistake".
Myself, I'm proposing a different method to verify the quoted figure.
Looking at Trenberth et al. (2014) fig. 1, it'd be nice to paste it here but I dunno how :( , which shows he net TOA radiation (down) from CCSM4, I eyball that from 1960 to 2000 (4 decades), the imbalance grew from 0 to about 0.7W/m2, which is roughly 0.17 per decade.
At the same time, the mean growth reate of CO2 from NOAA increased from just under 1ppm/y to 2ppm/y. Current growth (2010+) is 2.5ppm/y. So, assuming CO2 is the only long term forcing agent here, we can say that the forcing is growing almost twice as fast (2.5ppm) as it used to in 1960-2000 on average (1.5ppm). Given that quoted figure (0.30) and my figure (0.17) eyeballed from Trenberth et al. (2014) fig. 1, are roughly in the ame proportion (almost twice as fast), I conclude that quoted figure (0.30) is correct. Obviously, my method (likewise yours) ignores other long term forcings - specifically CFC emissions that stopped in late 80s + human aerosols seems to be important players here - inclusion of other forcings may change the result.
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rab at 11:01 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
@rocketeer, Quick calculation: 360 million km^2 is ocean surface area, times 2000m comes to 72 times 10^22 cm^3. Divide this from 20 times 10^22 Joules (since 1980). This is 0.28 Joules per gram. Divide this from heat capacity which is 4.2 Joules per g per degreeC. This gives about 1/15 degreeC. Sounds like not much, but calculate thermal expansion. For water at the average temperature this is 0.0002 per degreeC (in volume), but 0.0006 per degreeC for linear. It's linear we want since surface is constant. Multiply by 1/15 degreeC and multiply by 2000m. Result is 8cm. This is a lot!
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Riduna at 10:56 AM on 1 February 2014Warming oceans consistent with rising sea level & global energy imbalance
The author notes that … “warming oceans account for about 35–40% of that rate of sea level rise over the past two decades, according to the IPCC AR5”.
I have long found it difficult to believe that thermal expansion of seawater is responsible for 40% of SLR. Recent research reports that melting ice sheets and mountain glaciers are about three times larger than steric influences on SLR.
That conclusion seems much closer to reality but may be unwelcome in some circles since the implication is that, if true and with SLR now at 3.4mm/annum, loss of land-based ice must be considerably greater than hitherto reported.
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Rob Painting at 10:51 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
John Wise - it seems to a be natural phenomenon tied to the poleward transport of heat. Stronger easterly trade and midlatitude westerly winds spin up the subtropical ocean gyres.
As the tropical surface water is pushed westward in opposition to the Earth's eastward rotation it decelerates, and thus has slower rotational velocity than the Earth below, and relative to other 'parcels' of seawater which are rotating at the same speed as the Earth. The Coriolis force points the decelerating parcel of seawater poleward. At the midlatitudes, the westerly winds push surface seawater eastward in the same direction as Earth's rotation. Relative to the Earth and other parcels of seawater, the wind-affected parcel is now accelerating, and is therefore directed equatorward by the Coriolic force. These two near-surface currents converge in the centre of the subtropical ocean gyres and, with nowhere else to go, the water is directed downward into the ocean interior (known as Ekman pumping).
This is where the majority of deep ocean warming is occurring in the last decade or so - in the subtropical gyres. A near-coherent spin-up of all five subtropical ocean gyres was observed from the early/mid 1990's through to about 2004, when a peak was reached. They have remained in a relatively intense state since then, with a little bit of a lull between 2006-2008.
The North Pacific subtropical gyre spun up intensely in the middle of the 2013 year, and the South Pacific subtropical gyre intensified leading up to the end of 2013. Both appear to have spun down substantially since then. The South Atlantic subtropical gyre seems still to be in a spun-up state. Based on our physical understanding of this wind-driven ocean circulation, these intense spin-ups should have transported more heat to the deep ocean.
When this wind-driven ocean circulation moves into its sluggish phase (the positive phase of the Interdecadal Pacific Oscillation [IPO]), surface warming is likely rise abruptly. There are some tentative signs that this process may already be underway, but I'll have to do a bit more digging to confirm this.
Moderator Response:[TD] Rob, maybe you could write a post about this? Perhaps a rebuttal to the myth "deep oceans can't gain heat unless surface oceans do first"?
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John Wise at 09:44 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
One Planet @ 5
I am aware of and have a basic understanding of the greenhouse effect,ocean acidification etc. What I am not clear on is what has changed in the last few years to cause more heat to be captured by the oceans and less in the atmosphere with the resultant slower rate of surface or atmospheric warming.
Moderator Response:[TD] La Nina: Trade winds push warm surface water to the west, which causes deeper, colder water to rise to replace it. See this post.
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chriskoz at 08:35 AM on 1 February 2014Corrections to Curry's Erroneous Comments on Ocean Heating
Phil@4,
Curry's nonsense statement involving 2nd law of thermodynamics appears to be the result of misunderstanding (or intentional misleading given her expertise) of the processes involved.
"Heat" does not come from the ocean. It comes from the sun. The GHG influence is to retain the incoming sun heat (due to TOA radiative imbalance), not procude it. Where in the OA system said retained heat goes, depends on local variations in insolation, weather etc. Those variations exists now and will always be. And they are unpredictable (weather), i.e. the energy flows between parts of the system may go back and forth depending on the differing amounts of heat said parts recieve, eg. due to variations in isolations. 2nd law of thermodynamics does not aply here. It applies to an isolated system in terms of energy flow. OA system is not isolated in that respect as everybody enjoying bathing in sunshine knows.
I'm sure Curry (climate scientist) understands the basics of OA system and 2nd law of thermodynamics better than I do (my degree is in unrelated discipline) so I think she applies said basic law of physics bogusly to intentionally mislead the listener. It is far less likely that she screws the science up because she does not understands it.
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michael sweet at 07:55 AM on 1 February 2014Warming oceans consistent with rising sea level & global energy imbalance
KR,
I had lost track of the discussion above.
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One Planet Only Forever at 07:39 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
John Wise @ 3.
The important point is that the planet is capturing more solar input energy because of increased greenhouse gases, particularly the increase in excess CO2 resulting from the burning of fossil fuels and other human impacts.
Until the surface warms to a level that emits radiation at a rate that is balanced with the higher level of energy capture there will continue to be 'net energy capture'. When the ocean surface is cooler, warmth is taken from the surface into deeper ocean layers that 'do not emit heat out of the planet'. The result is energy capture in the oceans until such time as the deeper heat rises to the surface. The next strong El Nino, like the ones that occurred in 1997-98 or 1982-83, could produce very dramatic increases in the surface temperature records. There are similar currents in other oceans, but there is a strong correlation between the Pacific Ocean ENSO (El Nino, La Nina), and significant bumps and dips in the surface temperature.
So, the 2013 global surface average being almost as warm as 1998 while the ENSO is in a slightly cooler than neutral phase indicates that warming has continued.
p.s. In addition to creating excess CO2 the burning of fossil fuels creates other damaging impacts. And it is fundamentally unsustainable because (burning up non-renewable resources). So the CO2 impact on the climate is only one of many reasons this activity needs to be curtailed, the sooner the better.
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scaddenp at 07:20 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
rocketeer - see discussion further up. here.
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Warming oceans consistent with rising sea level & global energy imbalance
michael sweet - 0.3 W/m2 per decade, as stated in the opening post, is the current rate of increase in that anthropogenic forcing value.
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michael sweet at 06:35 AM on 1 February 2014Warming oceans consistent with rising sea level & global energy imbalance
KR,
Your graph is very useful for the discussion. I read the total forcing as 1.6 W/m2, not as 0.3 W/m2. Look at the brick red bar labeled "total net anthropogenic" and the graph at the bottom. That appears to be the total forcing since 1750. Where do you see 0.3 as the final number?
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John Wise at 06:25 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
What has caused the heating of the ocean to increase and the heating of the atmpsphere to slow down in recent years?
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Magma at 04:31 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
Clever cultural reference in the headline.
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rocketeer at 04:07 AM on 1 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
Can anyone tell me what the heat content scale translats into in terms of average temperature increase? Easy calculation if I knew the mass of the ocean.
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citizenschallenge at 03:11 AM on 1 February 2014The Weekly Standard's Lindzen puff piece exemplifies the conservative media's climate failures
Mike that (conservamerica.org/) looks interesting, thanks for the link. Unfortunately, I noticed "ConservAmerica was founded in 1995 to resurrect the GOP's great conservation tradition and to restore natural resource conservation and sound environmental protection as fundamental elements of the Republican Party's vision for America." Tragically it seems they haven't had much impact on the GOP mind-set.
~ ~ ~Hope you don't mind me sharing a link myself:
Friday, January 31, 2014
"Dr. Richard Lindzen, scientist as fiction writer"
http://whatsupwiththatwatts.blogspot.com/2014/01/dr-lindzen-scientist-as-fiction-writer.html
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Warming oceans consistent with rising sea level & global energy imbalance
I believe that the 0.3W/m2 figure is for the sum of imbalance from 1750, the most commonly used IPCC baseline - the accumulated anthropogenic emissions forcing. Warming over the last 150 years has certainly cancelled out some of that imbalance, but it's not unreasonable to look at totals rather than year to year values when discussing GHG forcing.
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Phil at 23:05 PM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Pierre Normandy, yes sorry. I misread your original compliant. Thanks to Tom @20 for attempting some quantitative analysis. My only contribution is qualatative; it is, of course, possible for the imbalance to increase - the rate of CO2 emission has to exceed the planets response. Tom calculation suggests that it does, but not as much as the figure quoted. I had assumed that this was a measured quantity, it would be interesting to know !
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Tom Curtis at 22:35 PM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Pierre Normand and Phil, an decadal increase of 0.3 W/m^2 is equivalent to a 5.8% per decade, or a 0.57% per annum increase in CO2, ignoring other anthropogenic factors. That is low relative to the current emissions rate, but possibly a reasonable estimate once all anthropogenic emissions are included.
Assume a equilibrium climate sensitivity for doubling CO2 of 3 degrees, and a transient climate response of 2 degrees. That means for each 1 degree increase in temperature, there is a 1.23 increase in OLR. Further assume that the forcing increases by 0.3 W/m^2 per decade. From the transient climate response, it follows that temperatures increase by 0.16 C per decade on average, and hence the upward LWR from the increase in temperature increases by 0.2 W/m^2. In this scenario, therefore, the energy imbalance increases by 0.1 W/m^2 per decade. Thus, contrary to Pierre Normand, a constant, linearly increase in forcing will result in a an average increase in the energy imbalance, decade by decade. The increase, however, is much smaller than the increase in forcing. It is about a third of the increase in forcing on the assumptions used above, but will vary with different assumptions.
Given this, it is likely that the 0.3 W/m^2 figure quoted in the article is a mistake, but it is possible that expected increase in forcing is greater than 0.3 W/m^2 per decade; and also that different assumptions were used in the calculation, resulting in a much higher relative increase in energy imbalance for a given increase in forcing. It would be good if Rob Painting or Keven Trenberth could clarrify.
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Pierre-Normand at 21:33 PM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Phil, you seem to be agreeing with all I said. This increase in surface radiation into space is proportional to what I called the "Planck response". If the anthropogenic forcing wouldn't keep increasing anymore (because we would manage to suddenly reduce CO2 emission to a level that merely compensates upkeep by sinks, somehow, and the atmospheric concentration would remain constant) then surface temperature would slowly rise until the TOA balance is restored (and then rise some more as slow feedbacks kick in). If, however, we just keep increasing the forcing, as we currently do, then the surface warming strives to restore the balance but can't keep up with the constantly increasing forcing (mainly because oceans are slow to warm) and the TOA imbalance is maintained. But it is not *increasing* by 0.3W/m^2 per decade as the article states. This would only occur if the surface did *not* warm, or warmed very little. Then there would be no Planck response and the imbalance would grow at a rate equal to the rate of forcing increase.
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Phil at 20:45 PM on 31 January 2014Corrections to Curry's Erroneous Comments on Ocean Heating
Is it just me, or does anyone else think that Curry's comment about the 2nd Law of Thermodynamics make an unreasonable assumption about what is going on ?
As I understand it, areas of the Planet such as the atmosphere, upper ocean, deep ocean etc. should, in a perfect(ly mixed) world increase in temperature uniformily (i.e. in step with each other). However kinetic processes can imped heat flows between these different areas, allowing localised heat gradients to temporarily occur. Presumably, eventually the gradient gets so steep that a tipping point occurs and the Planet shifts into another phase where another area of the Earth warms preferentially to the others.
However the 2nd law of thermodynamics would only be relevant if we knew the rate at which the deep ocean was warming (or whatever area of the Earth was relevant at the time) was still below the "uniform" rate. If it wasn't then we would expect the 2nd law to "encourage" heat to be released.
Curry's statement therefore implies to me that she knows the deep oceans are still "playing catchup". Is she justified in this ? Or am I misunderstanding something ?
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Phil at 20:17 PM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Pierre-Normand @17. If the amount of energy received by the Earth from the Sun exceeds the amount the Earth radiates into space, then the only thing the Earth can do is increase its temperature, which in turn will increase the amount of radiation into space. This process will continue until these two energy fluxes are equal. In that time to reach a new equilibrium the amount of energy "stored" in the planet will increase, raising the temperature of the Earth.
Thus the rise of temperature of the surface (and all other portions of the planet) is caused by the global energy imbalance.
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Pierre-Normand at 17:19 PM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
"What's more, continually increasing greenhouse gases increase the imbalance by about 0.3 W/m2 per decade even as the planet warms and radiates some extra heat back to space."
I don't get this at all. It seems prima facie false. I would have thought that it is, on the contrary, *only* if surface temperature does *not* increase at all that the imbalance will keep increasing in exact proportion to the increase in external forcing (isn't it the anthropogenic forcing change, and not the rate of increase of the imbalance, which precisely is 0.3 W/m^2/decade?).
When the surface temperature is allowed to keep up, in accordance to the transient climate sensitivity to the forcing change (i.e. TCR * delta_forcing(t)), then the imbalance should remain constant since the Planck response balances out the forcing increase. The existence of the sustained imbalance, averaged over a couple decades, is mainly a result of slow ocean diffusivity, and the steadily increasing forcing, while it (the imbalance) fluctuates around this average value as a result of internal variability (ENSO etc.)
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scaddenp at 17:07 PM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Your number sounds more reasonable. Miscounted a zero somewhere.
The 9% is temperature. Increase of .37 on average temp of 3.9C. So make that 0.9% which sounds much more reasonable.
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jyyh at 14:26 PM on 31 January 2014It’s all a Question of Balance
"...and then, seeing the awesome power of living nature and the magnitudes of the cycles of local CO2 consentrations it produces, the physicist said, 'we may need an Earth System Model.'"
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jyyh at 14:22 PM on 31 January 2014Cowtan and Way: Surface temperature data update
At last, a longer temperature dataset fot the whole globe produced partly by a European working scientists. Thank you, all involved. Anyway the difference to the GISS data set is small but it's nice to have a European source for the global temperatures. The occasional cable breaks under the Atlantic are not an issue anymore.
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chriskoz at 13:26 PM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
scaddenp@14,
You'r off (exaggerated) by factor of 10.
1.3 billion cubic kilometres = 1.3E9 * 1E9 m3 = 1.3E9 * 1E9 *1E6 cm3
1cm3 takes 4.19J per 1K => total ocean heat content per 1K is: 1.3E9 * 1E9 *1E6 * 4.19 = 5.45E24J. So, according to this calculation dT of ocean would be 0.04K on average. However because we don't measure ocean heat content below 2000m (about half of the total volume), the OHC you cite applies to the top half volume only, so the average dT in this part of volume is just under 0.1K (0.08) consistent with the estimates.
However your statement:
change since 1970 [...] a bit under 0.4C. Still average ocean temp is 4C so that is 9%.
does not make sense both logistically and technically. Where did you take that "9%" from? I guess from the diference between ocean heat content over freezing point as opposed to the OHC change since 1970? Saltwater freezing point is about -2C rather than zero, so in that case you miscalculated your "9%". In any case such number does not make any sense in context of Earth energy imbalance topic at hand.
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scaddenp at 10:44 AM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
As a percentage change in temperature for entire ocean, it is small - because you need gigantic amounts of energy to shift the temperature of 1.3 billion cubic kilometres by 1 degree. 5.4E23J by my calculation, and change since 1970 has be 2E23J so I guess a bit under 0.4C. Still average ocean temp is 4C so that is 9%. More than I would have thought so perhaps someone should check my calculation. But so what? The measured change tells us what the energy imbalance for the earth is. Percentage change isnt a particularly useful indicator of hazard. Try increasing the percentage of cyanide gas around you by 0.027% for instance.
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Muzz at 09:59 AM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
I would like to know by what percentage the oceans are warming. Does anyone know the answer?
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michael sweet at 07:12 AM on 31 January 2014A Historical Perspective on Arctic Warming: Part One
Maurice Winn,
I do not see where the 1938 map has ill defined areas of land. Please specify where you see ill defined areas. There are many Inuit settlements across the Arctic that observed the ice every year and towns in Russia. On September 12, 1876 no less than a dozen vessels were caught in the ice and abandoned northeast of Point Barrow. These were whaling vessels. In addition there were many trading vessels and as you mentioned air planes from the various countries in the area surveying the ice. This documents that dozens of ships traveled the Arctic every year tracking the ice. You are claiming ignorance of information when you are presented with data. You have not looked up what the sources of the data are.
Your last line summarizes your lack of knowledge. Look at the North West passage. It is choked with ice in 1938 (and all other years until 2006). In 2012 there is little ice. There is shorefast ice at Barrow in 1938 and hundreds of miles of open water in 2012. "not all that much different from 2012" is simply wishful thnking on your part.
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MauriceWinn at 06:47 AM on 31 January 2014A Historical Perspective on Arctic Warming: Part One
Oops, no edit function. Sorry. That should be: <<Since the land in 1938 was ill-defined, it seems a stretch to think that the ice, which changes constantly, every summer, would be anywhere near as well-defined as the land. >> I inadvertently reversed my meaning by adding a "not" where I should not have done. It isn't that I didn't put "not", it's that I did [I hope that triple inverted negative gets a small smile].
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michael sweet at 06:41 AM on 31 January 2014Corrections to Curry's Erroneous Comments on Ocean Heating
Tamino's post (noted by Wili) would be good here at SkS. I am sure he would agree to cross post it.
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MauriceWinn at 06:40 AM on 31 January 2014A Historical Perspective on Arctic Warming: Part One
Comparing the summer 1938 map of Arctic ice with the 2012 map of Arctic ice, the land mass surrounding the ice is ill-defined. Presumably the 2012 map is the correct definition of land in the Arctic. Since the land in 1938 was ill-defined, it seems a stretch to think that the ice, which changes constantly, every summer, would not be anywhere near as well-defined as the land.
To define the extent of ice in 1938 would require a lot of ships sailing around reporting ice extent. It looks as though there was a lot of interpolation - "There is ice here so there is probably ice further on, where we can't go, so let's just fill it in with ice". As is evident from the 2012 map of the ice, it would have taken just a bit more ice to block off the Bering Sea access which would lead people in the day to assume that everywhere beyond the beginning of the ice would be continuous ice, which was not the case in 2012, when there were satellites to easily take handy photos to remove all doubt.
To map the minimum of summer ice in 1938 would have been impossible, as ice changes quickly in the heat of summer. One day a lake has ice, a week or two later, hey presto it's gone. Ships couldn't be everywhere at the minimum. The date in August 1938 would be relevant to the comparison. Maybe they missed the minimum by 3 weeks.
There were of course no satellites in 1938 and not a lot of aircraft flying over the area to report on something which was far less interesting than the Japanese and German rampaging murderous expansions across the planet, not to mention the USSR writ large and dangerous.
The Great Depression was on too, so there were not the swarming hordes of wealthy people with the luxury of investigating all sorts of natural phenomena.
The land mass is inaccurate, the ice extent is bound to be.
In any event, even if the reported 1938 ice coverage was accurate, it's not all that much different from 2012.
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william5331 at 05:20 AM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Presumably this heat in the oceans will make itself felt when, for instance, we have an El Nino. The inertia of the system implies momentum (actually the same thing in physics) and suggests that even if we ceased to warm the oceans, the effects of the warmer ocean will persis long after. Of course, even if we ceased to put carbon in the atmosphere tomorrow, the warming would continue until the various carbon sinks had time to reduce atmospheric carbon so we can't even stop the warming of the oceans if we wanted to. We truly are leaving a mess for our children.
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Andy Skuce at 05:09 AM on 31 January 2014Answering questions about consensus in a MOOC webinar
Actually, kanspaugh, the survey did include some articles from trade journals, such as the Oil and Gas Journal as well as from non-climate science journals such as the Bulletin of the American Association of Petroleum Geologists. The criteria for inclusion in the survey were that the article be peer-reviewed and that the papers appeared using our search terms.
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Rob Painting at 05:01 AM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Barry @ 8 - " Consistent with prevailing theories on the 'pause' slower rate of surface warming?"
Yup. See old SkS posts:
1. The Deep Ocean Warms When Global Surface Temperatures Stall
2. Ocean Heat Poised To Come Back And Haunt Us?
3. A Looming Climate Shift: Will Ocean Heat Come Back to Haunt us?
The stronger mixing of heat into the deep ocean during the negative (cool) phase of the Interdecadal Pacific Oscillation (IPO) would seem to be the primary suspect for the slower rate of surface warming, but light-blocking aerosols (around 20% according to one estimate) and a cooler than normal sun are also factors.
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WheelsOC at 04:14 AM on 31 January 2014Corrections to Curry's Erroneous Comments on Ocean Heating
Fourth and most importantly, the argument is a non sequitur – the conclusion doesn't follow from the premise of the argument. Yes, global warming events have occurred naturally in the past, and sea level rose as a consequence, but that doesn't tell us anything about the causes of the current global warming. This is akin to seeing a dead body with a knife sticking out the back and arguing that it must have been a natural death because people have died naturally in the past.
I've often used the analogy to wildfires when somebody says that "climate's changed before, I guess it was the dinosaurs driving their SUVs?" or something to that effect. The reply is that wildfires happened before any of the first humans were born, then ask if this implies that no wildfires are casued by people today.
For people who aren't prepared to accept that there actually is a knife in the victim's back (that we KNOW the Greenhouse Effect is playing the principal role right now), this is a subtler way to undermind their confidence in the myth of "just natural warming."
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wili at 03:34 AM on 31 January 2014Corrections to Curry's Erroneous Comments on Ocean Heating
Tamino has a new and unusually good--even by his high standards--post on why there is no 'hiatus' even in atmospheric global temperatures.
http://tamino.wordpress.com/2014/01/30/global-temperature-the-post-1998-surprise/#more-6942
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Prufrocks at 03:13 AM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
I am reminded of how often Pielke Sr. would dismiss surface air temperatures as a poor metric for global warming, in favor of OHC. His blog now long closed, Is he commenting or contributing elsewhere regarding the warming ocean? The last I've seen of him was in praise of Bob Tisdale who, I have to admit, sometimes give me pause and along with Judith Curry are pretty much my only remaining sources for "balance." (My impression is that Curry's recent Congressional statement regarding sea level rise is probably inaccuarate and dismissible but I don't think she addressed OHC specifically).
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Daniel Bailey at 02:48 AM on 31 January 2014Warming oceans consistent with rising sea level & global energy imbalance
In order for subaerial volcanoes to warm the ocean, they would have to be erupting on orders of magnitude larger than observed. This also would be affecting the acidification of the ocean, which we know is derived from human FF usages. Per Gerlach 2011:
"To create more than 35 gigatons per year of volcanic CO2 would require that magma across the globe be produced in amounts exceeding 850 cubic kilometers per year, even for magma hypothetically containing 1.5-weight-percent CO2. It is implausible that this much magma production—more than 40 times the annual midocean ridge magma supply—is going unnoticed, on land or beneath the sea. Besides, the release of more than 35 gigatons per year of volcanic CO2 into the ocean would overwhelm the observed acid-buffering capacity of seawater and contradict seawater’s role as a major sink for atmospheric CO2 [Walker, 1983; Khatiwala et al., 2009]. In short, the belief that volcanic CO2exceeds anthropogenic CO2 implies either unbelievable volumes of magma production or unbelievable concentrations of magmatic CO2. These dilemmas and their related problematic implications corroborate the observational evidence that volcanoes emit far less CO2 than human activities.
It is informative to calculate volcanic analogs that elucidate the size of humanity’s carbon footprint by scaling up volcanism to the hypothetical intensity required to generate CO2 emissions at anthropogenic levels. For example, using the 2010 ACM factor of 135 (Figure 1) to scale up features of present-day volcanism, Kilauea volcano scales up to the equivalent of 135 Kilauea volcanoes; scaling up all active subaerial volcanoes evokes a landscape with the equivalent of about 9500 active present-day volcanoes [Siebert et al., 2010]. Similarly, the seafloor mid-ocean ridge system scales up to the equivalent of 135 such systems. Of particular interest, though, is the roughly 4 cubic kilometers per year of current global volcanic magma production [Crisp, 1984], which would scale up to about 540 cubic kilometers per year. This significantly exceeds the estimated average magma output rates of continental flood basalt volcanism [Self, 2010], which range from about 10 to 100 cubic kilometers per year. Thus, annual anthropogenic CO2 emissions may already exceed the annual CO2 emissions of several continental flood basalt eruptions, consistent with the findings of Self et al. [2005]."
http://www.agu.org/pubs/pdf/2011EO240001.pdf
It's not subaerial volcanoes.
(emphasis added)
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