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Comment on Taxonomy of climate/energy policy perspectives by Vaughan Pratt

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<i>The new type of methanation plant can fit inside a standard shipping container,</i> <a href="http://thejetsons.wikia.com/wiki/Jane_Jetson" rel="nofollow">Jane Jetson</a> may have something to say to George about that. ;)

Comment on Questioning the robustness of the climate modeling paradigm by David in TX

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Fast : Cheap : Good

Choose any two.

Comment on Taxonomy of climate/energy policy perspectives by Vaughan Pratt

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If your basket included EOG Resources or Devon Energy, both of which went up 10% in the past 30 days, you did well. According to <a href="http://www.ft.com/intl/cms/s/2/1fedfe66-7f9b-11e4-b4f5-00144feabdc0.html#slide0" rel="nofollow">FT</a> they have good cash flow and little debt.

Comment on Taxonomy of climate/energy policy perspectives by Vaughan Pratt

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Unfortunately, neither you nor anybody else can manage to warm anything at all by surrounding it with any sort of insulator, CO2 included.

So there is no point in adding insulation to your house, or putting on a sweater?

Of the many remarkable facts you’ve discovered, this one is near the top.

Comment on On determination of tropical feedbacks by tonyb

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Greg

This item was referring to the lifetimes work of Hubert Lamb. Do you agree with it?

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This painstaking work, using scientific reports from the well-documented eruption of Krakatoa in 1883, and also from Iceland, the Mediterranean, Alaska, Greenland, Kamchatka, and elsewhere, led to his thesis which developed an assessment of the world’s volcanic eruptions since 1500. His paper, ‘Volcanic dust in the atmosphere… A chronology and assessment of its meteorological significance’, was published by the Royal Society in 1970. And with its publication, the Lamb Dust Veil Index entered the scientific literature.

My investigations had shown that beyond reasonable doubt that great volcanic eruptions do affect the weather and climate for several years afterwards, while suspended materials – not only the fine dust, but minute droplets and even gases – thrown up into the atmosphere by the blast are still present. 2

The study showed that it was the greatest explosions in the low latitudes between about 30°N and 30°S that most regularly yield products that spread around the world, and that the most regular effect of such eruptions was a weakening of the strength of the global circulation. Whereas an eruption in the middle and high latitudes tended to strengthen the circulation in that hemisphere.”

——- ——–
tonyb

Comment on On determination of tropical feedbacks by Rud Istvan

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Doubtful. Vulcanism is a function of plate tectonics. There is some literature suggesting tidal forces may affect timing of events. But virtually all volcanos save Hawaii are either on spreading rifts (Iceland) or over subduction zones (US west Coast), locations fixed in time by plate edges (well fixed to within a couple of centimeters/yr tectonic motion. Hawaii sits over a mantle plume hotspot; a ‘hole’ in a Pacific plate.

Comment on Taxonomy of climate/energy policy perspectives by Vaughan Pratt

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me: This would subtract some 140 ppmv from the CO2 level,

Scrub that, I naively copied my 143 ppmv figure from my previous calculation without paying attention to where it came from.

If terrrestrial plant biomass increased 50% by 2075, today’s downtake of 123 GtC/yr by terrestrial plants would be 185 GtC/yr by then, an increase of 61 GtC/yr or 28.7 ppmv/yr as I calculated earlier. Assuming a sustained CAGR for our CO2 emissions of 2.5% (the average since 1985), by 2075 we’d be emitting 44 GtC/yr. So the terrestrial plants alone would be pulling down considerably more CO2 than we’d be emitting then, to say nothing of the ocean.

This assumes that the increase in the terrestrial CO2 sink of 1 GtC/yr since 1988 is sustained to 2075, a linear extrapolation. My guess would be that that rate of CO2 consumption, fueled by the growth of our CO2 emissions, would be unsustainable and that the terrestrial sink should slow down.

Comment on On determination of tropical feedbacks by Greg Goodman

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Hi Tony.

Well the “minute droplets” are the volcanic aerosols that this post is all about. They undoubtedly do produce and initial cooling. The question I’m raising is whether there is a counteracting net warming forcing that follows.


Comment on On determination of tropical feedbacks by Jonathan Abbott

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Vuk,

Surely the productivity of Icelandic volcanoes is due to their geological structure, not the latitude at which they are sited? (Just to clarify)

Comment on On determination of tropical feedbacks by curryja

Comment on Taxonomy of climate/energy policy perspectives by jim2

Comment on Taxonomy of climate/energy policy perspectives by PA

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Rob Ellison | February 6, 2015 at 3:05 am |
CO2 from fossil fuels is some 57% of total greenhouse gas emissions. Black carbon has a bigger forcing. CO2 from electricity generation is even less significant.

So what? Emissions are meaningless if they are absorbed.

2/3 of the CO2 increase is natural.

Further – your story line that the fossil fuel emissions are the source of the CO2 increase are contrary to the visible distribution of CO2. The NH emissions appear to be mostly reabsorbed.

The largest CO2 hot spots are in the Southern Hemisphere. This is consistent with the estimate that 40 Gt/y of sink capacity was burned away in the Southern Hemisphere. The problem isn’t more emissions but less sinking.

So human emissions are contributing but as a minor player.

Comment on On determination of tropical feedbacks by Rud Istvan

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Hi Tony. There are two interesting corollaries to Lamb’s thesis. One is that most volcanos have a volcanic explosive index (VEI, log scale) of 4 or below. Most VEI 4 do not have enough power to reach the stratosphere. The last 4 that did, Surychev on Russia’s Kamchatka Penninsula, still had 95% of its ejecta wash out in three months. Essay Blowing Smoke. The second observation is that the big ones (VEI 5 or 6) happen mostly to be in latitudes +/- 30 N/S because that is where the most active subduction zones presently are. Basaltic eruptions (Iceland spreading rift, Hawaii plume) tend not to have as much ash and aerosol due to the much less gassy composition of mantle magma compared to recycled crustal rock magma. All of plate tectonic geology only really got started in 1967, so would not have been known to Lamb at the time of his thesis. So VEI and magma types that corollate with his observations would not have been easy to include. Regards.

Comment on On determination of tropical feedbacks by Jonathan Abbott

Comment on On determination of tropical feedbacks by Matthew R Marler

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Greg Goodman, congratulations on a good post. And thank you.

The values for volcanic aerosol forcing derived here being in agreement with the physics-based assessments of Lacis et al. imply much stronger negative feedbacks must be in operation in the tropics than those resulting from the currently used model “parameterisations” and the much weaker AOD scaling factor.

These two results indicate that secondary effects of volcanism may have actually contributed to the late 20th century warming. This, along with the absence of any major eruptions since Mt Pinatubo, could go a long way to explaining the discrepancy between climate models and the relative stability of observational temperatures measurements since the turn of the century.

My expectation is that much work like this, improving current approximations with better approximations and more detailed study of the processes that are modeled in the GCMs will, over the next 2 decades, produce GCMs that are more accurate. This is the kind of thing that Kuhn called “normal science” or “puzzle-solving”, but not revolutionary or requiring new paradigms.

You posed this problem above: Given that there are persistent temperature gradients between the tropics and the poles, and persistent energy transfers from the tropics to the poles, why is the TOA radiative balance in the tropics so close to 0? Any ideas?


Comment on On determination of tropical feedbacks by Tonyb

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Hi Rud

Coincidentally I am just graphing the largest volcanos against my extended CET to 1538 . I am using this so am including the VEI

http://en.m.wikipedia.org/wiki/List_of_large_volcanic_eruptions

It’s very difficult to determine cause and effect because for example huaynaputina in 1600 coincides with a very cold year but this was merely one in a series of cold years prior to the eruption. Santorini in 1650 had no impact at all in a sequence of warm years whilst Tambora in 1815, ‘ the year without a summer’ was again merely one in a series of cold years preceding it which also coincided with the Dalton minimum.

I am working it into an article on volcanos I shall call blowing smoke. Hey! You’ve already used that title!

Tonyb

Comment on Questioning the robustness of the climate modeling paradigm by Matthew R Marler

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Don Monfort: Are you saying that the reference he gave doesn’t prove that,

In the references that he gave, I did not find support for his claim that the models had been tuned to give the best 10, 20, and 30 year hindcasts. The excerpts that I copied and pasted here suggest to me a more thoughtful and physics-oriented approach to parameterisations, including the citations of other published papers.

It will be interesting to see whether, and how, the modeling community responds to Greg Goodman’s analysis of the Mt Pinatubo eruption in the post of today.

Comment on Taxonomy of climate/energy policy perspectives by Rob Ellison

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The question is net flux to the atmosphere. Emissions from soils and tropical vegetation have increased wit temperature – e.g. http://judithcurry.com/2013/06/07/soil-carbon-permanent-pasture-as-an-approach-to-co2-sequestration/

The increase from tropical veg and soils is about 50% of human emissions over the past few decades. Solubility in oceans is a minor effect.

The changes are what is significant – not the flux totals which net out to zilch if the atmosphere if the concentrations don’t change much. But they are changing and are exceeding anything seen in the Holcene apparently – and seemingly going higher.

Your simplistic prognostications notwithstanding. We have little confidence in understanding of the system – but we do know that human emissions have increased to 34.7 billion tons CO2 annually. Approximately. And this is not the entire story by far on emissions of greenhouse gases, black carbon and aerosols.

Comment on On determination of tropical feedbacks by Greg Goodman

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Water vapour + air is less dense than dry air. Thus a local hotspot on SST will cause evaporation which leads to convections. This brings in surrounding air to replace the rising moist air inducing local wind increase. Wind increases evaporation plus surface agitation with also increases evaporation. That is a positive feedback which leads to towering column of cloud that flattens to the characteristic anvil of a tropical storm when it hits the tropopause.

As always, the +ve f/b has to be constrained by more powerful -ve f/b at some stage or else the whole system would be unstable. This sort of situation can lead to “emergent phenomena” where some small random fluctuation develops by +’ve f/b into a large scale event.

I think this is the point Eschenbach has been trying to make for a number of years in his posts at WUWT.

However, viewed on a larger scale this is a negative feedback to the local SST hotspot. Therefore the internal +ve f/b makes this a non-linear -ve f/b on SST. ie. a very powerful -ve feedback.

The strong volcanic forcing I derived in this article requires such a strong negative feedback in the tropics. Which, in turn, implies a low climate sensitivity.

Comment on On determination of tropical feedbacks by Tonyb

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Jonathan

See my reply to Rud above. I have had this conversation numerous times over the last two years with RGates. Where is he?

Many volcanoes appear to be merely set in a period of already cold years. Some appear to cause warming, if they have any impact at all . Others might cause cooling but it is difficult to separate them from what might have happened anyway bearing in mind the fluctuating temperatures in the years around them.
Tonyb

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