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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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gws at 00:41 AM on 31 January 2014Methane emissions from oil & gas development
Informative story on NPR this morning:
Much of North Dakota's Natural Gas is going up in Flames
Situation is similar in Texas.
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barry1487 at 21:54 PM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
chris & Glenn,
While ENSO maybe the primary factor in ocean/atmosphere heat flux, it is not the only mechanism. Trenberth's paper is trying to resolve the energy budget on interannual scale, but I am interested in decadal trends. (I'm not sure if the paper says that they are better resolved or not) There has been much discussion attributing the 'pause' in surface temps since the turn of the millenium to accelerated uptake of energy in the oceans. This would seem to be corroborated in the OHC data since the turn of the millenium. So I looked further back to see if that kind of correlation was evident, using OHC as the pacemaker.
For periods when there was a clear linear trend change in OHC (0-700 & 0-2000), there seems to be an inverse correlation with surface temperatures. I added a few more trend lines to surface data here.
The first 2 trendlines are sub-decadal and should be ignored (although they fit my hypothesis) , but the following 3 are decadal periods with distinct trends. ENSO is not factored because it is a component of total OHC.
The three decadal surface temp trends behave as I imagine for periods when OHC rises quickly or is flattish. OHC has a steep warming trend 1969 - 1979 (incl), has a much lower trend 1980 - 1990, and a steep trend again 2000 - 2014. Surface trend for those periods are, inversely, flattish, steeply warming, and flattish again. IIRC, long-term volcanic forcing is negligible, and solar influence is not a major factor (15% on decadal time scales according to Trenberth). I didn't attempt to run a trend for 1990 - 2000, as OHC trend for that period was hard to read.
I don't know if there may be something to accounting for surface/ocean trends on decadal scales, but I was interested in the possibility in light of the recent 'haiatus' in surface temperatures. From Trenberth's paper:
Several runs with the model under future emissions scenarios where the radiative imbalance is known exactly and a distinct energy imbalance at TOA was occurring nonetheless featured several stases in surface temperatures for more than a decade. Examination of the energy flows during such intervals for all ensemble members reveals a consistent picture. The net radiation at the TOA (RT) was on the order of 1 W m-‐2 into the climate system, yet there was a stasis in warming at the surface. Examination of the changes in OHC showed clearly that this was the main sink. Indeed, the full depth OHC continued relentlessly upwards with no hesitation at all. Hence the missing heat was being deposited mainly below 700m depth....
Consistent with prevailing theories on the 'pause'?
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chriskoz at 19:56 PM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
wwsyim@5,
No, we haven't "overlooked" the role of submarine volcanic eruptions.
The 'heat' of underwater volcanic eruptions you're presumably refering to, is part of earth's geothermal etnergy. The total geothermal energy was mesured as 0.1W/m2, which is much less than current toa imbalance. You can read about it, e.g. here:
What might be causing the imbalance? Might it be heat flowing from within the Earth? Apparently not. Pollack et al 1993 estimated total geothermal heat flows from within the Earth at 44.2 trillion Watts. This is only around 1/6th of the observed heat build-up
Out of that 0.1W/m2, volcanoes are only a part. Your volcanoes (underrwater) are still ~3/4 of total volcanoes on the globe. So I can confidently say that the heat of your volcanoes is at least 10 times smaller than the heat retained due to TOA imbalance. To have a little bit of understanding about the enormity of TOA imbalance, you can read further therin:It [imbalance] would now take all of 100 minutes to boil Sydney harbour dry
Any of your volcanoes would be able to do it? It would be an enormous volcano that no one has seen yet... Of course, one can find & claim that that some specific eruption warmed ocean water by several degrees and caused change of currents and that may have even contributed to the reversal of ENSO oscillations. But it's going to be only local and minor event. Globally, the biggest factor is imbalance due to GHG.
The "natural" CO2 emissions from all volcanoes are 100times smaller than human emissions, as you can read here. So the volcanic CO2 is also a minor factor.
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Rob Painting at 17:10 PM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
wwsyim - the global oceans are warming from the top down. There are many other lines of evidence, but this alone precludes submarine volcanoes as a culprit.
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wwsyim at 16:22 PM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
Submarine volcanic eruptions have always been an episodic natural contributor to ocean warming. For example the El Hierro submarine volcanic eruption in the Canary Archipelago, off the northwest African coast from October 2011 to March 2012.
How can we distinguish between ocean warming due to natural and anthropogenic causes? - or have we entirely overlooked the role of submarine volcanic eruptions.
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Glenn Tamblyn at 16:16 PM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
barry @1
Actually from your graph, 0-700 and 0-2000 OHC seems to have moved in lock-step from 57 - 83 with a blip around 75. Implying no long term heating in 700-2000. Then from 83-86 0-2000 rose faster implying heating in 700-2000. Then from 86 to 94 0-2000 matched 0-100 so no warming od 700-2000. Then from 94 onwards 700-2000 started warming continuously.
Perhaps 700-2000 actually started warming around 83 onwards with something suspending that from 86 to 94.
And what could cause these sorts of fluctuations? Winds. Increased winds in the tropics and mid latitudes can 'spin up' the mid-ocean gyres, increasing the rate at which water gets pumped down to mid depths through Ekman pumping, taking heat from the surface with it.
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R. Gates at 15:23 PM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
I think this general analysis is right on target and the "pause" in the accumulation of energy in the Earth climate system is indeed an illusion. Tropospheric sensible heat is a poor proxy for measuring the energy gain in the Earth system. It is only a partially good proxy over the longest time frames. The Earth climate system continues to gain energy from the geologically rapid build up of GH gases caused by human activity.
Having said all this however, let me correct what I think is a basic thermodynamic error that many make when saying the "heat is going into the oceans" from anthropogenic global warming. By a very very big margin, the net flow of latent and sensible heat is from ocean to atmosphere on a global basis. The atmosphere simply does not heat the ocean-- quite the opposite. What increasing GH gases do is alter the rate of energy flow from ocean to atmosphere to space. The oceans gain energy because this flow is reduced. Much of this addition energy in the ocean is advected to the poles (especially the north pole, due to the hemispheric energy flux differences). Thus we see much if the sea ice decline actually occuring from ice being melted from the bottom From warmer water. Thus, a slightly warmer atmosphere acts like a control knob to create a much warmer ocean and even faster warming polar region.
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chriskoz at 12:45 PM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
barry@1,
If you think about the fact that OHC trend is responsible for over 90% of warming due to TOA imbalance, you may reasonably expect the surface T changes (where only 3% of that imbalance energy goes) will not be very well correlated. It's hard to establish precise correlation from when other factors (volcanoe aerosols, sun's variability) are coming into play and influence TOA balance.
However your remark:
the cursory implication is that warming slows or stops at the surface for periods that OHC rises quickly
can be interpreted as an indication of LaNina conditions (ENSO minus zero) that may have prevailed during your periods. You would have to consider other effects (volcanoes & sun variability) to establish your correlation.
Trenberth et al. (2014) cited in the article is an excelent analysis of OHC/ENSO and TOA imbalance that may help you.
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barry1487 at 11:30 AM on 30 January 2014Warming oceans consistent with rising sea level & global energy imbalance
OHC trend was also relatively strong between 1969 - 1979, similar to the period since 2000.
For both periods HadCRUt4 shows flattish surface trends.
It's just two periods, but the cursory implication is that warming slows or stops at the surface for periods that OHC rises quickly. Is there a long-term correlation, and does anyone know of published literature on this?
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VictorVenema at 11:22 AM on 30 January 2014A Historical Perspective on Arctic Warming: Part One
It could be that the IPCC was right, but Curry was wrong. There is namely an important sentence missing from Curry’s quote h/t Steve Bloom:
“A question as recently as six years ago was whether the recent Arctic warming and sea ice loss was unique in the instrumental record and whether the observed trend would continue (Serreze et al., 2007).”
In other words, the IPCC was describing the way science saw the situation 6 years ago. Six years makes quite a difference as the temperature increase was strong the last few years. For more details see my blog.
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A Historical Perspective on Arctic Warming: Part One
These sea ice maps from 1938 (the summer with least sea ice during the ECWP) and the record year 2012 confirms what the temperature records say about the Arctic, namely that the warming around 1930-1940 was not comparable to the warming we see today.
And even if it was, it’s worth noting that the areas north of 60°N and 70°N cover no more than about 7% and 3% of the Earths surface, respectively. A significant warming here could easily be offset by an insignificant cooling in the rest of the world without affecting the global temperature.
Source: Danish Meteorological Institute (DMI) and NSIDC.
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A Historical Perspective on Arctic Warming: Part One
An update on my previous post - Dr. Curry's Georgia Tech publication list shows about 154 titles, meaning that just under 1/3 (45) concern the Arctic. Again, she should know what she is talking about, making her Congressional testimony puzzling.
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A Historical Perspective on Arctic Warming: Part One
A quick look at Dr. Currys publication history shows two instances of 'Antarctic', and 45 of 'Arctic '. Only 5 on 'temperature', however (note: her publications go back to 1983, well over 100 listed). She appears to know a lot about the Arctic.
Given that publication history and the existing Arctic data, these postions in her testimony seem quite out of place.
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CBDunkerson at 05:42 AM on 30 January 2014A Historical Perspective on Arctic Warming: Part One
Albatross raises an interesting point. Curry has an extensive publication history... but I can't recall having seen her publish any peer reviewed 'research' on her climate denial talking points.
Her participation in the 'BEST' study would have been a perfect example... except that it wound up showing that her claims were false... and then, of course, she disavowed it.
Has she published 'denial research' that I have missed? Her claims on scientists (including her own BEST study) 'hiding the decline' were particularly egregious... yet she made her 'case' entirely in the field of 'journalism' rather than science.
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tkman0 at 04:03 AM on 30 January 2014A Historical Perspective on Arctic Warming: Part One
Thats a great Idea ^^
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Philippe Chantreau at 03:33 AM on 30 January 2014A Historical Perspective on Arctic Warming: Part One
Very good point Albatross, Willard's playing on words does not fool anyone. Curry's testimony in Congress had little more value than that of Monckton. Robert Way is one of many regular contributors to SkS who can claim publication in a serious journal. It is one more in a list that is becoming significant and continues to grow. I'm not sure if this is the right thread but I would like to propose a new tab on the upper left of the home page: "SkS authors/contributors climate science articles." Anyone else thinks it's a good idea? I'm not suggesting competiton with RC but something that would allow newcomers to see that this site is not to be given the same weight as clowns like Goddard or other internet junk...
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JoeT at 14:01 PM on 29 January 2014Real Skepticism About the New Marcott 'Hockey Stick'
Hey Tom, thanks very much for a very cogent explanation. I appreciate it.
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Albatross at 13:28 PM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
To be fair, I am going to issue a challenge to Dr. Curry. If Dr. Curry honestly believes that her opinions have scientific merit and/or are novel, then I challenge her to publish (as sole author) a paper on each one of her claims made to Congress in a reputable peer-reviewed journal such as Quarterly Journal of the Royal Meteorological Society, Journal of Climate, or Climate Dynamics, or International Journal of Climatology or Geophysical Research letters.
Cowtan and Way did so.... -
Albatross at 13:21 PM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
Between Robert's post and the post by Tamino, Dr. Curry has again been shown to wrong (how many times has that happened now?). She was wrong in her claims about sea level, she was wrong in her claims about what decadal variability means for climate sensitivity, she was wrong about the implications of the Antarctic sea ice extent increasing slowly. It is quite obvious that Dr. Curry is doing whatever it takes to feed the beloved uncertainty monster that she recently conjured up;)
I hope that it is not lost on readers that Robert Way and Tamino have (unlike Dr. Curry) objectively analyzed the data. Robert's line plots, density plot and box and whisker plot demonstrate unequivocally that Dr. Curry's claims are simply and comppletely wrong. I would go further and argue that she was playing loose with the truth and facts in her testimony to Congress. She only has two options here-- either she is being disingenuous or she is not qualified to speak to the science of AGW.This sort of unprofessional conduct by Dr. Curry is completely unjustified, indefensible and reprehensible. I can't imagine why anyone with integrity or standards would even begin to try and defend Dr. Curry's unethical behaviour.
Another important result arising from this is that the IPCC tends to be, if anything, too conservative.
Moderator Response:[PS] This comment is on thin ice with respect to both inflammatory tone and accusations of deception. Let's keep this civil.
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Tom Curtis at 10:39 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
Willard:
"I conclude that this article is mainly a promotional token for Cowtan & Way"
There is no warrant for the claim that this article is "a promotional token", which gives the appearance of disproof by slander. Robert Way cited 10 distinct data sets, only one of which is his own.
Of course, the statement may well be true. Willard may conclude whatever Willard likes, regardless of the merits of the case. In this case, however, Willard's conclusion reflects poorly on him.
Moderator Response:Before things go way offtopic with discussions of symantics and motivations which will be tedious for moderators, can I suggest instead Willard points to data that supports the Curry statement so that discussion can be more focussed on the science.
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Rob Honeycutt at 10:35 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
Willard... First, not to nit-pick but these are "blog posts" rather than "op-eds." An Op-Ed would be something related to print media or an invited column from an invited outside person. Blog posts are usually owned by the blogger, or as with Robert, by someone who is a regular author of the blog.
That aside, as for "going a bridge too far," I don't agree. Look at Tamino's list of graphs from all the papers that are cited in the quote you provide from Curry. Even based on on the cited references you can't support the claim that the 1930's were warmer than the 2000's.
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Tom Curtis at 10:34 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
Willard:
"Reading back that thread might show that the claim "there is no support for that [Judy's and the IPCC's] position" might be going a bridge too far, and has been offered by Rob Honeycutt as a proof by assertion."
Rather than a bridge to far, it is clear understatement. Every temperature record examined showing both 1930s and 2000s Arctic temperatures shows the later to be warmer than the former. Further, the only clear statement on the issue in the IPCC's supporting literature flatly contradicts their (and Curry's) claim.
Willard, condemning "proof by assertion" does not justify your attempting the same.
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Tom Curtis at 10:31 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
First, Tamino now has a follow up article on this issue.
In it he examines the temperature data presented in:
Polyakov et al (2003)
Wood and Overland (2010)
Yamanouchi (2011)
Fyfe et al (2013)
Johannessen (2004)
Bekryaev et al (2010)
He discusses these because they are the articles Curry cites in her defense. Tamino shows that none of them show temperatures in the 2000s as cold as those in the 1930s. That is, the literature Curry cites do not support her conclusion, and where they show both 1930s and 2000s temperatures, refute it.
In the list above, the bolded articles are also cited by the IPCC in the section quoted by Willard. It is far from clear that the articles cited by the IPCC are in support of the disputed claim. When making that claim, ie, that "Arctic temperature anomalies in the 1930s were apparently as large as those in the 1990s and 2000s", they cite no literature in suport of the claim. Above (@1), Willard critiques the OP on the basis that there is no "... discussion of the rationale behind the IPCC's claim". In fact there is no discussion of the rationale behind the IPCC's claim in AR5 WG1. Criticizing Way for not reproducing or quoting what does not exist is bizarre. It shows that Willard has, at best, "phoned in" his initial critique,ie, that it is not based on an assessment of either the IPCC's discussion or of the literature.
I had expected better from Willard.
The IPCC also cites:
Ahlmann (1948)
Veryard (1963)
Hegerl (2007b)
Ahlmann and Veriyard are clearly too early to be relevant, not being able to compare 1930s even with 1990s temperatures - let alone those of the 2000s.
Hegerl et al (2007a) discusses attribution in relation to a reconstruction of NH temperatures from 30 to 90 degrees North, and contains no distinct discussion or representation of Arctic only temperatures. Further, the reconstruction terminates in 1990, making it irrelevant to the question at hand.
Hegerl et al (2007b) ie, AR4 WG1 Chapt 9 shows no pan-arctic temperatures, but those that it does show for individual Arctic areas show 1930s temperatures below temperatures in the 2000s.
Brohan et al (2006) introduces the HadCRUT3 which is superceded by HadCRUT4 which shows Arctic temperatures warmer in the 2000s than in the 1930s.
Bengtsson et al (2004) shows Arctic temperatures warmer than in the 1930s by the late 1990s, and does not show temperatures of the 2000s.
I do not have access to the full text of Grant et al (2009), but its abstract restricts its discussion entirely to the early twentieth century. That makes it unlikely that it will contradict what appears to be a concensus in the literature that actually discusses or shows a comparison between 1930s and 2000s Arctic temperatures. That is particularly the case as Grant et al (2009) share three coauthors with Bronniman et al (2012), including both Grant and Bronnimann.
Bronnimann et al (2012) conclude that:
"None of the data sets alone is sufficient for addressing long-term trends in the Arctic. However, knowing the shortcomings and differences, information can be gained even on trends from analysing all data sets individually and by combining the results (see also Thorne et al. 2010 for the value of multiple tropospheric temperature data sets). For instance, all data sets agree that the last two decades are unprecedented in the 20th century in terms of the magnitude of the warm anomaly in the lower troposphere.The rate of warming between the 1980s and present is also outstanding. The vertical structure of the trend shows a clear amplification of the recent trend at the surface in autumn to spring. During the ETCW, high temperature anomalies were also found at 700 hPa and above in winter. Although the data are more uncertain for the first half of the twentieth century, they clearly point to a smaller lapse rate compared to the recent warm period."
(My emphasis)
To summarize, the IPCC claim has no supporting evidence in any of their cited literature that I have been able to examine, and flatly contradicts all of the standard temperature records, and the only clear statement on the subject in the literature they cite.
I believe that shows Willard's critique to have been entirely baseless.
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willard at 09:52 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
> No, that is not what Dr Curry quoted.
Here is where Dr. Curry quoted what I said she quoted.
Following that op-ed published on January 27, 2014, there are some comments by Robert Way in the comment section, dated January 28, 2014 at 11:32 am, 11:57 am, 1:23 pm, 1:49 pm, and 4:34 pm.
My understanding is that Robert Way's op-ed has been published on January 28, 2014.
Reading back that thread might show that the claim "there is no support for that [Judy's and the IPCC's] position" might be going a bridge too far, and has been offered by Rob Honeycutt as a proof by assertion.
***
If we're supposed to evaluate the accuracy of the statement "Arctic temperature anomalies in the 1930s were apparently as large as those in the 1990s and 2000s", a statement we can find in the IPCC documentation, then we wish to pay due diligence to what contains the IPCC documents and drop anything that has yet to appear there.
If what we want is to put emphasis on new, cutting-edge peer-review literature, then I suggest we clarify what kind of "Historical Perspective" is intended.
Moderator Response:[PS] fixed link.
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Rob Honeycutt at 09:37 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
I have to say, I find Dr Curry's response less than adequate. She's merely retreating to the idea that we can't really know if the temperature of the 1930's was warmer or not because the Arctic has poor coverage.
Once again, this completely contradicts the entire thesis of what she was presenting to the Senate committee! You can't claim on one hand, in front of elected officials and the general public, that AR5 actually reduces our certainty about AGW, and then turn around and claim in a blog post that the data are insuffient to even know.
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Rob Honeycutt at 09:23 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
And Tamino already has a response to Curry's response.
http://tamino.wordpress.com/2014/01/28/judith-curry-responds-sort-of/
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barry1487 at 09:14 AM on 29 January 2014Australia’s hottest year was no freak event: humans caused it
mchael sweet @ 45,
Climate change is projected to bring more water vapour but this is not uniform across the globe. Changes to the hydrological cycle vary by region. In Australia there has been increased precipitation in the North West, and decrease in the South West. Increasing drought is predicted for some regions but not for others. Rule of thumb is that wet regions will get wetter, and dry regions will get dryer. Tropical zones will see more rainfall and cloudiness, and the sub-tropics will become more arid. That's the general idea, though projections are not so spatially strict as this generalization, but the point is that climate change changes weather patterns n ways that are not uniform. Regional projections are less certain than global, so the comments here should be read with that in mind.
How this might change cloudiness (and solar exposure) nationally is less clear. Increased water vapour should increase cloudiness. Rainfall is projected to become less frequent but more intense in some parts of Australia, and there are seasonal differences. AR4 projections on precipitation in Australia are here.
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Charlie A at 09:01 AM on 29 January 2014A Historical Perspective on Arctic Warming: Part One
Judith Curry has a recent blogpost on this subject at http://judithcurry.com/2014/01/27/early-20th-century-arctic-warming/
Her original testimony can be found at http://www.epw.senate.gov/public/index.cfm?FuseAction=Files.View&FileStore_id=07472bb4-3eeb-42da-a49d-964165860275
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cpslashm at 08:34 AM on 29 January 2014It hasn't warmed since 1998
Tom Curtis @275, thanks for your response.
I was looking at the data from the opposite perspective: a sharp increase in energy going into melting ice from 2003. Is the trend real? Where is the extra energy coming from? What other part of the system is losing out? I am assuming that the bulk of the heat is being transported to the sea ice via the Arctic near-surface waters which then have less heat to pass up to the atmosphere. If this absorption of heat from Arctic waters by ice melt does not produce a corresponding loss of atmospheric heat input, I will have to look elsewhere.
The amount of heat melting Arctic sea ice per average year since 2003 is minor but enough to raise the temperature of the top three metres of the Arctic Ocean by 1 degree C. I have not yet found a correlation with sea ice area minima which would be the case if the melting were due mainly to a progressive loss of albedo. I am not convinced of the relevance of sea ice extent in this case.
To come back on topic, although minor compared to oceanic heat absorption, melting sea ice demonstrates that a lot of near-surface heating has been going on since 1998 which will not have contributed to a global surface temperature rise.
The advantage with my hypothesis is that it can be proved wrong within the next four years - I hope!
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Tom Curtis at 08:16 AM on 29 January 2014Real Skepticism About the New Marcott 'Hockey Stick'
Joe T @100, you have picked up on one of the most interesting and innovative features of Marcott's reconstruction. Instead of just making a central estimate of the temperature, and showing error bars, they varied the data based on the error margins of the original proxies. By doing this, they get statistical data on all the ways that the reconstruction could be wrong. From among all those variations, only 18% of ten year intervals are warmer than 2000-2009. Allowing for some inherent smoothing in the method, that becomes 28%. That does not mean that there were any decades warmer than 2000-2009 in the Holocene. The actual temperature record will approximate to one of their statistical variations of the data, their "realizations". It is, however, as likely to be a cold realization as a warm one. Because reconstructions can be wrong by being to warm, or to cold, with equal probability, the mean does not vary as much as the realizations can, and does not show the potential warmest years.
This explanation will be easier to understand if you actually see the realizations plotted with the mean:
The idea is that current temperatures, while much higher than the mean (black line), are not higher than about the warmest of the realizations in for any given decade about 18% of the time.
The net effect from this can be seen in Marcott's Fig 3:
The 2000-2009 temperatures, with an anomaly of about 0.4 C lies in the upper end of the distribution of realizaitons (solid black curve). These can then be compared with the expected temperatures from various IPCC AR4 scenarios. (The coloured curves represent alternative means of reconstruction, and can be ignored for this discussion.)
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A Historical Perspective on Arctic Warming: Part One
Curry has clearly made this claim, as per her testimony, stating:
Arctic surface temperature anomalies in the 1930’s were as large as the recent temperature anomalies.
That link would be good to add to the OP.
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