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dlen at 08:33 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
AFAIK the el nino southern oscillation has been made responsible for the low temperatures especially in 2008 and 2012, which contribute most to the impression of some warming pause. (Foster and Rahmstorf).
It is unclear to me - and may be to others - in what relation the trade wind strengthening stand to ENSO. Both phenomena operate on the same theatre with the water body of the pacific ocean beeing shoveled over in this or the other direction.
Does anybody can give a clarification or a link to one?
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Mike3267 at 07:55 AM on 12 February 2014A methane mystery: Scientists probe unanswered questions about methane and climate change
The article did not discuss processes that remove methane from the atmosphere. I assume these would primarily be oxidation and absorption by the oceans. Is it clear these have a steady rate, or could these rates change?
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Andy Skuce at 07:51 AM on 12 February 2014A methane mystery: Scientists probe unanswered questions about methane and climate change
It is interesting to note that the global bottom-up methane emission estimates are more than the top-down measurements. Local and regional studies generally show the opposite tendency (see this recent SkS post by gws).
I am not quite sure what to make of that. I suppose that most of it can be attributed to a lack of adequate local and regional measurements and uncertainties in natural and human emissions rates used in the bottom-up calculations.
The other figure in the article shows a remarkable change in the distribution and amount of global emissions, starting in 2007. The authors point out that the recent rise in methane emissions is dominated by non-fossil sources, which perhaps suggests a link to global climate change, but exactly to what factors exactly is not clear.
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kanspaugh at 07:31 AM on 12 February 2014Establishing consensus is vital for climate action
Yes, "clarifying the existence" of the consensus is the problem and goal. This was easier to do with the consensus over the harmful effects of tobacco smoke, since almost everyone knew someone who was a habitual smoker and got sick / died from it. Really drove home the point. No means quite so pointed and personal of underscoring the existence of consensus over AGW. Not as simple, of course, to attribute suffering and death from extreme weather events to global warming than it is to attribute cancer / heart disease to smoking.
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Jim Eager at 06:17 AM on 12 February 2014A methane mystery: Scientists probe unanswered questions about methane and climate change
Two other notable anthropogenic sources of methane worth mentioning are our cattle herding and wet rice agriculture.
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scaddenp at 06:15 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
I am well aware of Svalgaard's opinions - he is a true skeptic as opposed to someone who is only skeptical of views opposed to their preconceptions - but my point is that none of the actual data supports solar involvement in recent warning. You seem to pinning hopes on some possible unknown rather than heeding the warnings from what is known from actual physics and measurement. It seems to me that your views on AGW are biased by an a priori position rather than informed by published science.
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ubrew12 at 04:51 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Isn't the engine for the trade winds the Hadley circulation, and the engine for that circulation is the heat pumped into the air by water changing phase (raining) at the equator? As water vapor increases with global warming, shouldn't this circulation become enhanced, and thus the trade winds enhanced as well? If so, the trade-wind shear-stress induced vertical ocean circulation (La Nina) may be a 'helpful' negative feedback in the next few decades. Helpful with climate consequences, though not with sea level rise.
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ianw01 at 04:34 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
mgardner@34: No, not worth further debate. I think we both know what's going on here, and probably either of us could edit Bob's post for dimensional correctness. As I'm sure he could too. :-)
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william5331 at 04:18 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
So perhaps we should push ahead with sail assisted ships pushed around the world by these enhanced trade winds. They weren't called trade winds for nothing.
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mgardner at 02:31 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
ianw01@32
I said I thought it was a great explanation, but I can elaborate on how it might be improved if you insist. Note that Bob was using the term shear "force" not "stress" of the wind when he introduced the block, and the transition to F/A was not overtly related back to the "stress" usage for wind. To my mind, the transitional sentence could be interpreted either way. Is it worth arguing about? -
Terranova at 02:20 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Does the paper entitled "Slowdown of the Walker circulation driven by tropical Indo-Pacific warming" by Tokinaga, et al, 2012, contradict the report referenced in your post? Help a biologist out!
The abstract for the paper can be found here.
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michael sweet at 01:58 AM on 12 February 20142014 SkS News Bulletin #1: Keystone XL Pipeline
Russ,
The issue is that you are making an incorrect argument. Since your argument is irrelevant to the discussion it is simple for me to conceed it. You are arguing that no single project measurably affects AGW therefor none should be opposed. This only demonstrates how large the fossil fuel industry is worldwide and emphasizes that all projects need to be opposed.
All projects are important to AGW. All projects need to be opposed. For several reasons I have already outlined, the KXL pipeline is especially bad and is appropriate to draw a line in the sand for.
The tragedy of the commons is that no one individual contributes greatly to the distruction of the commons. The combined effect of everyone is to destroy the commons. The solution is for everyone to help conserve the commons.
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ianw01 at 00:50 AM on 12 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
mgardner @29: You are correct that the friction force in the block example is independent of area (for first order effects). However, the reason the area was (correctly) brought into the discussion by BobLoblaw is that the goal was to express the horizontal force on a per-unit-area basis. (i.e. as a shear stress). Stress is force per unit area.
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One Planet Only Forever at 00:30 AM on 12 February 20142013 was the second-hottest year on record without an El Niño
Klapper,
More 'on topic', are you looking exclusively at the trend of values in the 'gaps' in the HadCRUT4 data coverage of the planet for all of te available ways of looking at trends in the 'gaps'?
If all you are doing is looking at data of a complete region , not just the clear gaps in the HadCRUT4 evaluation (and choosing one data set as the basis for making a point), any 'conclusion' would be unproven. That would be similar to reviewing the global average surface temperature trend since 1998 without considering the 'noise' of things like the ENSO and volcanic events (which is exactly the point of this article). After an ENSO as powerful as the 1997/98 event, with as little volcanic dimming as occurred in that time period, it would be possible to come to a reasonable 'conclusion' about a 'warming trend rate'. Until then any claims based just on the values would be unfounded.
The point of my larger comment was a reasoned explanation of the persistence of unfounded questions being raised, even after they have been answered. Some people do not want this issue to be better understood. Some people just want to 'raise doubts' any way they can get away with for as long as they can get away with.
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Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Klapper #22:
None of the graphs in Svalgaard’s paper support the idea that solar activity is responsible for any of the recent global warming (last 30-40 years), not even Shapiro’s controversial TSI reconstruction in the right panel of figure 5. (read why it’s controversial and probably wrong here)
I didn’t say the sun peaked 50 years ago, but “more than 50 years ago”. Maybe I should have been more precise and said 1958, as these graphs show:
Anyway, the fingerprints of the recent warming don’t fit the “it’s the sun” claim. For instance, more warming in winter than summer in the Arctic is the opposite of what the sun is expected to do.
So I’m pretty sure that the sun has no responsibility for the recent warming, although it probably played a role before 1960.
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Russ R. at 00:12 AM on 12 February 20142014 SkS News Bulletin #1: Keystone XL Pipeline
scaddenp,
After the numerous, ridiculously generous assumptions I made, I don't think you have any justification to quibble over my numbers. I agree that there are other exernalities not accounted for in my analysis, but you'll find the same is true of all energy technologies (solar, nuclear, wind, battery, etc.). We can debate the magnitudes, but you should at least acknowledge their existence.
vrooomie,
The Scientific American article you linked to answers a rather different question (What is the impact of the entire Alberta tar sands on global warming?) and answers that question (0.4C), making no mention of the fact that the Keystone XL pipeline would require ~6,000 years to pump that volume of crude. It also blissfully ignores the fact that other fossil fuels will be burned if the tar sands are not.
michael sweet,
thank you for conceding my argument that the KXL pipeline is meaningless to the climate. I trust you will henceforth be quick to correct those misinformed individuals claiming that the pipeline's impact will be catastrophic (or even measurable).
In closing, I would be more than happy to not use the "A-word", but only when this site stops using the "D-word". I fully agree that a more constructive debate will result when everyone sticks to facts and leaves out the name-calling.
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howardlee at 23:40 PM on 11 February 2014The Oceans Warmed up Sharply in 2013: We're Going to Need a Bigger Graph
In a weird way, isn't the fact that deep oceans are warming actually (slightly) good news? Let me explain.
As I understand it, there are (simply put) fast feedbacks and slow feedbacks. The conventional wisdom is that in the time since the industrial era, only the fast feedbacks have been operating (surface ocean, lapse rate, sea ice, snow, water vapor, biosphere). Our rate of CO2 increase has been outstripping their ability to absorb CO2.
Slow feedbacks including the deep ocean, are meant to cut in only after a number of centuries to millennia.
If we have evidence that the deep ocean is coming "into play" NOW, that implies surface-deep heat exchange and therefore, presumably, gas exchange. If so, even though we keep building heat in the planetary system (bad news I get it) from a surface point of view, might this buy a few more decades to get emissions down (assuming actual political & business action)?
By bringing the deep ocean into play, it's like turning on a bigger AC - with observed changes to surface global temps in recent years.
Against this idea is the fact that CO2 has continued to rise without any apparent inflection, but then we are cranking it out at such a rate that's not really surprising.
I don't see how we can get heat into the deep oceans without also getting CO2 into the deep oceans.
I'm not an oceanographer but it would seem important to understand the physical location(s) geographically of this extra heat and if its associated with a current, when will that current return those extra joules to the surface? That would be a bad year. If the deep currents are slow we may have a couple of extra decades before then, unless thermal instability disrupts those currents...
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CBDunkerson at 22:32 PM on 11 February 2014Warming oceans consistent with rising sea level & global energy imbalance
It isn't a direct measure of temperature, but Bering sea ice is currently very low for this time of year.
This winter a lot of warm air has been pulled up into the Arctic... which in turn has pushed cold air down into the eastern U.S. Climate deniers have been out in force in my area, 'Look, snow! So much for global warming'... yet I can remember that 30 years ago the winters were routinely colder and more snow covered even than this. The fact that the Arctic has seen an abnormally warm winter could also lead to a large sea ice melt this summer.
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Klapper at 22:07 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
@ scaddenp #26:
Here's a quote from the link you posted (Svalgaard 2013).
"It should be clear that there is no consensus and that the question mark in the title of the present paper is fully justified: we do not know what the variation of solar activity has been even over the most recent 170 years, let alone in centuries and millennia past. It is somewhat of a travesty that we cannot provide the climate research community with that fundamental piece of input to their debate."
The aa-index is what it is. Whatever proxies you use to reconstruct the magnetic activity of the sun, here down on earth the actual measurements show a steady increase to at least the very end of the 20th century. Perhaps there are complications of how the solar wind and magnetic activity interact. I don't know, but certainly there is room to speculate that indirect solar effects need not have peaked 50 years ago, particularly in light of Svalgaard's quote above. -
mgardner at 21:18 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Bob Loblaw @17
A great explanation; I too had no clue about the wind stuff, but here's a nitpick in the interest of basic physics purity: The friction for a sliding dry block isn't dependent on surface area.
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michael sweet at 21:13 PM on 11 February 2014Warming oceans consistent with rising sea level & global energy imbalance
Elmwood,
Neven's Arctic Sea Ice Graphs page has a lot of graphs that cover Alaska. If you are a casual reader there are a lot of graphs to look through. This page shows the daily and weekly sea temperature anomalies worldwide. It currently shows the Bearing sea as warm. I do not remember a week this year when the Bearing sea was cold, it has been warm or neutral. There is a large hot spot south of Alaska in the North Pacific ocean. It has been there for months.
Yesterdays temperature anomaly plot for the entire world shows Anchorage cool as you describe. The weekly product is still not working.
I imagine your news sources are fairly biased in Alaska. This is a good site to ask questions. We all are interested in weaknesses, they show areas you can learn more.
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Xolin at 18:01 PM on 11 February 2014Why rainbows and oil slicks help to show the greenhouse effect
UBrew12 @ #13
I don't wish to dismiss your analogy out of hand - because analogies can be useful in explaining abstract concepts to laypeople - but your dye in a swimming pool explanation is almost, but not quite, entirely incorrect in demonstrating the effect of CO2 concentrations in the atmosphere.
The pool dye advertised (apart from its almost complete lack of usefulness in anything other than some trivial First World sense) has none of the properties of CO2, does not behave in the atmposphere as CO2 does, nor does it emulate any of the physics necessary to explain CO2 influence. Suffice it to say - without boring all in the know - that explanations of the electromagnetic energy transfer and blocking mechanisms of CO2, its mixing levels at given temperatures and energy levels, and its raison d'etre in the equations of a myriad thermodynamic equations (such as the Stefan-Boltzmann), amongst other things, using an analogy that only shows a superficial resemblance to reality is misleading and unhelpful.
We need to argue against the deniers with objective, scientifically robust and valid empirical proof. Otherwise we risk dissembling into argument entropy where each side attempts to explain hyper-complex realms with simpler and simpler examples that results in a complete loss of any form of epistemological basis...And I, for one, would rather 'lose' an argument to a denier than relinquish that.
Moderator Response:[PW] To all:
I'm as vociferous a fan of 'outing' those who dismiss the science of climate change as any, but let's all *drop* the use of the d-word; if you feel compelled, use 'dismissive,' or 'pseudoskeptic.' It only gives the dismissives ammo and it doesn't truly reflect the reality. There are true skeptics--pretty much 100% of all scientists--and pseudoskeptics, those who have little to no training in what they are dismissing. Not only do we need to "argue against the deniers with objective, scientifically robust and valid empirical proof.", we also need to do it as respectfully as we can.
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jsam at 17:50 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
There is much concerned spluttering in denierdom. "We were told in 2006 that the Pacific winds were slowing", citing Vecchi 2006.
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GFW at 17:13 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
I just wanted to third what Elmwood and Wili asked (and thank Chriskoz for a partial answer). I think answering this question more completely, with understanding of the physical processes is critical to predicting the rate of surface warming. -
scaddenp at 16:17 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
As far as I know, PDO may be little more than average from several superimposed processes each of which is more or less understood. I dont think there is a "switch" - just reflecting the chaotic processes underlying ENSO. Part of the heat redistribution engine. See for instance here and here.
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Elmwood at 14:53 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
wili,
i speculated the same thing, that the fact the trade winds are so anomalously strong, that it might be related to AGW and act as some sort of "negative feedback" even though the surface and oceans still warm. the big question is what is causing the switch from negative to postitive PDO indices? i don't think anyone has a clue.
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Elmwood at 14:33 PM on 11 February 2014Warming oceans consistent with rising sea level & global energy imbalance
michael,
i thought i heard that the bering sea was still colder than normal on the radio (i live in anchorage). we did have near record warm last month but now it's probably below normal if anything. i've never seen a january or february with so little snow, it all melted. big oil up here has every politician in their pockets. i work in this industry as a government regulator and naturally have a lot of interest in this subject. just trying to find any weaknesses in the theory of AGW. so far i haven't found any. thanks.
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scaddenp at 13:10 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Klapper, for the parameter that matters - the energy we get from the sun - I dont such a peak. Can you reconcile your statement with the data presented in this paper please?
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barry1487 at 12:50 PM on 11 February 2014Australia’s hottest year was no freak event: humans caused it
If you're still reading bruiser.
I selected 40 station records at least 80 years long (couple of exceptions), with none starting after 1909. There were quite a few that didn't extend to the 2000s, and about half had data prior to 1900.Eyeballing the min/max graphs provided, 30 showed warmer temps in the last two decades of the period, 18 showed cooler, and 12 showed little change.
Chose the records from here if you want to check for yourself.
There are wild departures in the data pre-1910 (in both directions). They are surely suspect.
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chriskoz at 12:41 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
wili@21,
That's an interesting question I presume no one has answered yet.
Mike Mann has an interesting op-ed where, in the context of England et al. 2014, he recalls Paul Handler mid-80s research and also his own research about volcanoes and ENSO correlation. Mike's hypothesis is that oceans act as "thermostat" in a sense that negative feedback of LaNina kicks in response to positive forcing (e.g. GHE), or ElNino in response to negative forcing (volcanoes). So, our ever-warming world could lead to a semi-permanent LaNina state. But not a word about physical mechanisms leading to it, let alone quantify the supposed negative ocean feedback.
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michael sweet at 12:23 PM on 11 February 20142014 SkS News Bulletin #1: Keystone XL Pipeline
Russ,
Deniers always claim that each single project has no measurable effect. I will even conceed your argument. Therefore we obviously have to stop every project because it is only by stopping them all that we have the desired effect. Additionally there is the point that if we build Keystone, what is the reason to stop the next project? All these projects need to be opposed since the longer it goes before they are built the more likely it is that renewable energy will price them out.
Keystone is especially bad because of its high carbon load.
Moderator Response:[PS] In the interests of constructive debate, can we keep the "alarmist/denier" name-calling out of it please? The names may or may not be accurate, but name-calling not encourage respect for writers argument. That means everyone.
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Klapper at 12:06 PM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
@ HK #20:
"if the surface warming from the late 1970's to about 2000 was mostly caused by release of ocean heat..."
Firstly, I didn't say "mostly" in my post, I said "some part". Secondly, I disagree the sun peaked 50 years ago (mid 1960's). That's nowhere close to the truth for some parameters.
The sun's magnetic activity is closely related to the length of the sunspot cycle. The shortest cycle since 1840 is the <10 year one ending in 1996. Plot up the aa-index and you will see it peaked at an all time record year in 2003. More important the successive 11 year peaks and valleys both climbed steadily from 1900 to 1992 or so, when the valley's started to decline (although the peaks kept climbing).
Since the 2003 peak there has been a sharp decline but clearly the upward trend continued for this solar parameter into the 21st century.
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vrooomie at 12:01 PM on 11 February 20142014 SkS News Bulletin #1: Keystone XL Pipeline
Russ R., SciAm seems to be not in agreement with your numbers.
There are also many more negative externalities of the fully-developed tar sands, not accounted for in your simple explanation. The Pembina Institute has an excellent paper on this.
http://www.pembina.org/pub/203
In closing, I'd suggest you lose the "A-word," as it poisons the well, wrt to constructive dialogue.
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One Planet Only Forever at 12:01 PM on 11 February 20142013 was the second-hottest year on record without an El Niño
Klapper and Markoh,
I have posted a version of my previous comment on the article suggested by the Moderator, including an edit to address Markoh's post.
Moderator Response:[PS] Thank you.
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One Planet Only Forever at 11:58 AM on 11 February 2014Carbon Emissions on Tragic Trajectory
'Global warning and climate change' is a sub-set of the bigger issue of the 'acceptability of continuing the fundamentally unsustainable and clearly damaging pursuit of benefit from the burning of fossil fuels'. Developing a better understanding of aspects is important, but many appear to seek opportunity to claim 'uncertainty about that clearly certain larger issue' by finding a way to raise a question about the minutia of a part of the larger issue to create the impressions of 'significant uncertainty about something there is no uncertainty about'.
The extraction and burning of fossil fuels cannot be continued for very much longer, and humanity has hundreds of millions, if not billions of years, to look forward to on this amazing planet. And there are many damaging impacts of the activity, including the impacts of the accumulation of excess CO2 (in the atmosphere and the oceans). There is also major harm cause by the conflict between powerful people fighting to get more of the potential benefit for themselves. Burning fossil fuels is an incredibly damaging activity ‘all things considered’.
An acceptable use of an unsustainable and damaging activity would be to address an ‘emergency’. I would accept that ‘emerging’ economies should be allowed to use the burning of fossil fuels to more rapidly transition their entire population into sustainable economic activity. However, this would have to be a brief transient phase. The the 'economic efficiency or return-on-investment needs to be excluded from determining how long the unustsianble and damaging stage is allowed to continue.
After all, any activity relying on burning fossil fuels is ultimately a damaging dead end that needs to be stopped, the sooner the better. Those economic activities simply cannot have sustained growth. And since the objective is to ‘lift the least fortunate into a sustainable better way of living’ the only ones benefiting from the burning of fossil fuels should be those who are the least fortunate. The same goes for any other unsustainable and damaging activity like the use of harmful chemicals or using up (consuming) other non-renewable resources. Everyone already ‘more fortunate’ should be ‘getting by with sustainable virtually damage free ways of living’. That is the only viable future for humanity. Anything else would be unsustainable and unacceptable.
This ‘required development to sustainable activity model’ is challenged by the fact that sustainable activities will always be less profitable and less desired than the more damaging or less sustainable activities that ‘can be gotten away with because of popular support’. The ‘profit motive’ and ‘potential popularity’ clearly cannot be allowed to determine what is acceptable…because they clearly haven’t and won’t.
So the clear facts of matter are that the basis for determining the acceptability of prolonging the burning fossil fuels cannot be if it is ‘popular and profitable in the moment’. It cannot be based on the desires of the already fortunate to continue to benefit from unsustainable and damaging activity they have ‘grown fond of getting away with benefiting from’.
The increased understanding among the global population of the unacceptable and significant impacts of excess CO2 is just one of the ways to help raise awareness of the fundamentally unsustainable and damaging ways that many among the most fortunate ‘strive to get away with for as long as they can get away with’. Discussing and debating details of sub-sets of the larger issue needs to be clearly understood to not reduce the urgency of ‘changing the minds, attitudes and actions’ of the population so that humanity actually develops a sustainable better future for all life on this amazing planet.
That is my opinion.
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One Planet Only Forever at 11:43 AM on 11 February 20142013 was the second-hottest year on record without an El Niño
Klapper,
You created the 'opening for my response' with your 'concluding statement about your question regarding filling gaps'.
How you might have deemed such a question to be worth repeating needed to be questioned.
Though this is indeed a site for discussing the details of the science, there seem to be times when the motivation behind persistent questions that have plausibly already been answered needs to be considered.
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scaddenp at 11:23 AM on 11 February 20142014 SkS News Bulletin #1: Keystone XL Pipeline
Being a little more careful with tone will help with getting a respectful debate.
One small quibble with numbers (I am not in American continent and thus have little interest or knowledge of keystone), but the 60% absorbtion is not a fixed number and will slowly decrease. At a certain point, warming oceans will emit CO2 though this isnt expected any time soon.
However, as far as I can see, the biggest objection to any new FF infrastructure like keystone is that it delays the transition to non-FF energy structures. Investment would be better in alternatives. I would agree that it is better to kill FF by reducing demand rather than constricting supply, but constriction of supply forces raises prices which has same effect. Of course the money from this increased carbon price goes to the remaining suppliers rather than everyone as it would under a pigovian tax, but it seems such a tax is politically impossible at the moment.
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Russ R. at 11:07 AM on 11 February 20142014 SkS News Bulletin #1: Keystone XL Pipeline
Basic math shows that when it comes to climate change, the Keystone XL pipeline is meaningless.
First, to avoid getting tangled up in endless debate over the sensitivity of the climate to greenhouse gases, let’s just assume the climate alarmists are right. They say that each doubling of CO2 warms the planet by 3°C (http://www.ipcc.ch/publications_and_data/ar4/syr/en/mains2-3.html). More recent empirical studies have placed this number at or below 2°C (http://www.nature.com/ngeo/journal/v6/n6/pdf/ngeo1836.pdf), but rather than argue, let’s just be generous and go with the 3°C value.
Let’s start with the expected state of the atmosphere, regardless of whether or not Keystone XL is built. Atmospheric CO2 is currently around 400ppm (http://keelingcurve.ucsd.edu/), and is expected to rise to at least 550 ppm in 100 years (http://www.ipcc.ch/pdf/assessment-report/ar4/wg3/ar4-wg3-spm.pdf).
What else do we know about how carbon dioxide emissions affect the atmosphere? We know that 60% of the carbon emitted doesn’t actually stay in the atmosphere, being instead recaptured by the oceans and biosphere (http://cdiac.ornl.gov/faq.html#Q7). We know it takes 2.13 gigatons of carbon emissions add one additional ppmv of CO2 in the atmosphere (http://cdiac.ornl.gov/faq.html#Q6). And we know from the molecular mass of carbon dioxide that 3.664 units of CO2 is equivalent to 1 unit of carbon. (http://cdiac.ornl.gov/faq.html#Q9)
Turning our attention to the proposed pipeline’s payload, we know that heavy oil from tar sands is more energy intensive to extract and refine. On a “well to wheels” basis Canadian bitumen contributes around more emissions than conventional light crude. To be precise, 559.6 vs. 438.6 kg CO2 / bbl. (http://www.api.org/aboutoilgas/oilsands/upload/cera_oil_sands_ghgs_us_oil_supply.pdf) But let’s be generous and assume that this isn’t a question of burning heavy oil instead of light oil... let’s assume it’s a question of heavy oil or no oil. (i.e. if the pipeline isn’t built, Americans will just do without the oil rather than replace it with some other source of oil.) Ridiculous I know, since Americans are already importing oil from Mexico, Nigeria and Venezuela, but never mind that… we’re being generous.
Let’s be even more generous and assume that if the pipeline isn’t built, that the oil won’t be transported south by rail, or piped to the west coast and shipped to Asia. Let’s assume it’ll just stay in the ground. Even more ridiculous, since it’s already being transported by railcar, but again... we’re being ridiculously generous.
So we’re assuming that every barrel of oil that flows through the pipeline will either be emitted into the atmosphere or stay safely in the tar sands. We’ll also make the impossible assumption that the pipeline will run at 100% of capacity, every minute, of every hour, 365 days of every year, for the next hundred years. This makes it easy to calculate the impact on the atmosphere and the climate over the next century, since we know the planned capacity of the Keystone XL pipeline is 830,000 bbl/day. (http://keystone-xl.com/about/the-project/)
From here, there’s nothing left to do but some simple math:
• 830,000 bbl/day capacity x .5596 tCO2/bbl = 464,468 tCO2/day
• 464,468 tCO2/day x 36,524 days/century = 16,964,229,232 tCO2/century
• 16,964,229,232 tCO2/century ÷ 3.664 C/CO2 = 4,626,607,972 tC/century
• 4,626,607,972 tC/century / 1,000,000,000 GtC/tC = 4.627 GtC/century
• 4.627 GtC/century x (1-60%) = 1.851 GtC /century
• 1.851 GtC/century ÷ 2.13GtC/ppmv = 0.869 ppmv/centurySo, if we assume that the pipeline runs at 100% of capacity, every minute of every day of every year, for the next hundred years, it would increase the concentration of CO2 in the atmosphere by 0.869 ppmv.
And what impact would that have on temperature? It would raise the atmosphere’s CO2 concentration from 550 ppmv to 550.869ppmv.
• ln((550.869)/550)/ln(2) = 0.00228 doublings of CO2/century,
• 0.00228 doublings/century x 3°C per doubling = 0.00683°C/centuryYes… that’s less than one one-hundredth of a degree Celsius per century. Looked at another way, even under ridiculously generous assumptions, the Keystone XL pipeline would have to run continuously at full capacity for 14,637 years in order to raise the planet’s temperature by a single degree Celsius.
But don’t take my word for it… do the math for yourself, and no matter what assumptions you make, you’ll come to the conclusion that the Keystone XL pipeline will have no measurable impact on the earth’s climate.
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wili at 10:27 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Why are the trade winds getting stronger? Is this itself a response to warming? Does this amount to a (temporary) negative feedback? What might reverse it?
I have a feeling that there are all sorts of other important mechanisms (existent and potential) of circulation in air and ocean that we still have little to no clue about.
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Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Klapper #2:
If the surface warming from the late 1970's to about 2000 was mostly caused by release of ocean heat trapped between 1940 and 1970, then the global surface temperature would have changed more or less like the blue curve here.
If there really was more heat accumulation in the oceans between 1940 and 1970, something else must have prevented the surface temperature from dropping during that period, just like something has prevented the surface temperature from dropping in the 2000's despite record high heat accumulation in the oceans in recent years.
That "something" is certainly not the sun, which had its highest recorded activity more than 50 years ago
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Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
KR #8:
BojanD and Klapper have a point regarding direct measurements of the TOA radiation – they are not accurate enough to tell us about the global energy balance, as Gavin states here.
The only direct evidence for a positive energy imbalance is the increase of the heat content in the climate system, most notably in the oceans. (and that has been significant!)
Figure 2 in your link (change in spectrum from 1970 to 1996) proves that the greenhouse effect has in fact increased, but it covers far from all of the Earth’s OLR.
A blackbody calculator reveals that the radiation in the range from 700 cm-1 to 1400 cm-1 only constitutes about 37% of all radiation from a body at 255 K (Earth’s temperature as "seen" from space). In theory, increased OLR on other frequencies could have offset the decrease in the range shown here.BTW, I don’t like the unit on the Y-axis (brightness temperature) because it exaggerates the impact of methane vs. CO2. The spectral radiance (W/m²/cm-1) at 255 K is over 4 times higher at 700 cm-1 than at 1300 cm-1, so a 1 K change in brightness temperature counts much more in the CO2 part of the spectrum than in the methane part.
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Markoh at 08:37 AM on 11 February 20142013 was the second-hottest year on record without an El Niño
One Planet. You state acceptability of emerging economies to use fossil fuels and then transition to renewables. However once the costly infrastructure to burn fossil fuels is built, there is a very long period to pay back this infrastructure, usually a minimum of 20 years. We already see with China that the installed capacity of coal fired power stations still increases year on year. The turning point has not been reached and China is now a major polluter.
Moderator Response:[PS] Okay, this is starting to wander off-topic. Perhaps continue the discussion here.
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scaddenp at 07:52 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
BojanD - what is the your problem with the OHC method of estimating TOA? Seems a pretty good way to do it to me.
Also, when you are talking about the global energy fluxs (which have to take into account both temporal and spatial sampling issues), the line between direct measurement and inferrred is somewhat blurred. However, for all the detail, the place to start is the Trenberth 2009 paper from which the diagram is drawn.
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Bob Loblaw at 07:08 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Magma: "Zonal wind stress trends (x10-1 N m-2/20 yr) is not a metric that that leaps intuitively to mind"
No, I'm sure it isn't, and I'm sure you're not the only one. If you don't make a living measuring turbulent energy transfer in the atmosphere, you're probably used to thinking of wind in terms of speed. Speed, however, is not a good indicator of the energy in the wind, due to several factors:
- it changes with height; roughly log-linear, meaning wind speed increases with height, proportional to the log of height (i.e., rate of change is greatest close to the surface). Normal meteorological procedure is to standardize measurements at 10m for reporting "surface" winds.
- the profile of wind speed depends (in part) on how rough the surface is (in addition to how hard the wind is blowing).
As a result, it is customary to express the effects of wind in terms of shear stress, which is a property that is roughly conserved over small vertical distances. For wind, the force exerted on the surface in a horizontal direction is a shear stress - a force that is trying to drag the earth in a horizontal direction. (Conversely, you can think of the earth as exerting a drag on the wind.) The lowest layer of the atmosphere is also subject to a shear stress from the moving air above it, and so on for each increase in height. Thus shear stress is a good indicator of the effects of wind. THe shear force, created by the circulation that makes the wind blow, is transferred downward to the surface through the lower atmosphere.
As analogy, think of a block sitting on the ground, with a rope attached. The weight of the block exerts a downward force, which is measured in Newtons (N). This downward force translates to a horizontal force, via friction - when we try to drag the block with the rope. The horizontal force is {weight X coefficient of friction}, but we need to account for the area of the block, too, so the term we really want is weight per unit area, or N/m2. This is the shear stress between the block and the ground (when we pull it), and the wind's shear stress has exactly the same effect.
So that explains the units. As for the negative sign: I suspect, but I am not sure (and the full article doesn't help)that the reason is as follows. One custom in measuring turbulent atmospheric motion is to make all fluxes directed away from the surface to be positive. Examples of such that make sense are thermal energy transfer (within the turbulently-mixed air) and the movement of water vapour away from the surface (AKA evaporation). For shear stress (also known as "momentum transfer"), the actual direction is from the top down: the air is dragging on the earth and transferring momentum from the atmosphere to the surface. So, being downward-directed, it ends up with a negative sign, and more negative means stronger forces.
As a last tangent, although pressure is also "force per unit area" and for pressure the units of N/m2 become Pascals (Pa), it is not correct to change the units of shear stress to Pa. Pressure is a non-directional force, whereas shear stress has a direction. Thus, the habit is to use N/m2.
Hope that helps.
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dana1981 at 06:17 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
John H @14 - deep ocean is usually defined as below 700m (that's the definition I use).
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BojanD at 06:04 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
We can measure relative changes at TOA, but not absolute not so well.
@Klapper, exactly my point and it was very explicitly stated by Gavin.
It would be very interesting to read an article showing which values in Trenberth's famous energy flow chart are directly measured and which ones are inferred, like energy imbalance.
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John Hartz at 05:42 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
@Dana: What is your working definition of "deep ocean"?
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Bob Lacatena at 05:35 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
Klapper,
The absolute numbers are very, very clear, because we are able to fairly accurately measure ocean heat content and other values which represent a gain in energy of the system. Then you divide that by time.
See KR's statement.
Basically, we know there is an imbalance at TOA, and the earth is accumulating energy, but due to the difficulty of precise measurements it is difficult to use that method to determine "how much".
But we can measure the temperature of the ocean, atmosphere and land, and the volume of ice that is permanently melting, and from that compute the change in heat content over the span of years. That tells us very accurately how much heat the planet is gaining over time (look at the widget in the upper right corner of the page).
There is no doubt here, and it is not assumptions, it is reliable measurements with well-defined and understood error bars. The earth climate system is gaining heat at an alarming rate. That is an incontrovertible fact. GHG theory predicts exactly such an accumulation of heat. All natural sources of warming are currently negative (i.e. point to cooling) and so cannot be contributing.The end result is that all warming (not some, not most, all) must be due to anthropogenic sources. The only argument we can have is one of land use versus greenhouse gases.
There is no magical heat source in the oceans that is confusing the issue.
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scaddenp at 05:29 AM on 11 February 2014Unprecedented trade wind strength is shifting global warming to the oceans, but for how much longer?
On the other hand, the Argo network determination of OHC does allow for absolute estimate of energy imbalance (though obviously with error limits) eg see Trenberth 2014.
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scaddenp at 05:22 AM on 11 February 20142013 was the second-hottest year on record without an El Niño
Actually, they use kriging methods to determine how closely spaced the drillholes should be. These days, you would of course test for spatial dependence rather than assume it, especially with ore grades.
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