530 AD y todo eso
Traducido por Angela Carosio
“en este año hubo un temido presagio. El sol dio su luz sin brillo…y parecía como un sol de eclipse, pues los rayos de luz no eran claros.”
Esta cita de Procopius de Cesarea es igual a las de otras fuentes alrededor del mundo y señala un fenómeno climático, generalmente conocido como niebla seca que viene acompañado por un verano frío, el fracaso de las cosechas y otra serie de problemas. En una serie de TV, libros y artículos en la prensa se sugirieren, como posibles causas, erupciones volcánicas, cometas y otras catástrofes. Pero esta semana se publicó un nuevo artículo en GRL que podría ofrecer una respuesta definitiva…
Es bien sabido que los anillos de crecimiento de los árboles (como el de la fotografía, proveniente de Arizona) generalmente muestran un anillo de crecimiento extremadamente pequeño para el año AD 536 (éste se puede contar hacia atrás desde el anillo marcado como AD 550.) En efecto, si observamos las anomalías de toda una serie de construcciones de anillos de crecimiento, este evento se destaca como excepcional en los últimos 2000 años, junto con los años 1601 y 1815 (ambos conocidos por erupciones volcánicas).
Fig. 1: Promedio de los componentes de alta frecuencia en 7 reconstrucciones de anillos de crecimiento de árboles del norte de Europa, por Larsen et al, 2008. El filtrado asegura que las incertidumbres en las tendencias a largo plazo (que no son importantes en este contexto) no confundan los resultados.
Estos datos coinciden con las fuentes escritas. Sin embargo, la búsqueda de una causa para AD 536 siempre ha estado plagada de problemas de cronología. El intento de asociar este evento con una erupción volcánica en las muestras de corazón hielo Dye3 de Groenlandia se desplomó cuando dicha cronología fue revisada y colocó al evento volcánico 20 años antes de AD 536. Sin embargo, recientemente ha habido un esfuerzo conjunto para ubicar todas las muestras de corazones de hielo de Groenlandia en una misma escala temporal, basada en el recuento anual de capas (Vintner et al. 2006). Debido a que todos los corazones de hielo están siendo analizados conjuntamente, las ambigüedades en un corazón pueden ser corregidas cotejando con otros. Una vez que los datos estén bien establecidos, los registros de sulfato (SO4) (que generalmente muestran el impacto de gases volcánicos), pueden ser examinados para ver si éstos coinciden. Y así lo hicieron:
El segundo pico de sulfato de la figura corresponde al año AD 534, que es suficientemente cercano a AD 536, dejando uno o dos años de error en el recuento. Se debe notar que el pico alcanzado en AD 534 es menor que el alcanzado unos años antes. Sin embargo, cuando se evalúa la importancia de una erupción, un pico de concentración de sulfato en Groenlandia no es suficiente, ya que esto podría significar que hubo una erupción en un área cercana. En vez, un pico de sulfato coincidente en la Antártida significa que la erupción ocurrió probablemente en algún lugar en el trópico y que la circulación atmosférica transportó los gases a ambos hemisferios. Es aquí donde intentos previos han fallado. La cronología de las muestras de corazones de hielo antárticos es mucho menos exacta que las de Groenlandia porque la acumulación en la Antártida es más lenta (no se nota tanto). Sin embargo, la relativamente nueva muestra de corazón de hielo llamada Dronning Maud Land (DML) tiene una resolución comparable con las muestras de Groenlandia, y ésta muestra un claro pico de sulfato alrededor del año 542 +/- 17 años. Este resultado es suficiente para coincidir con el pico de sulfato de AD 536 en Groenlandia. La corrección necesaria para que estos eventos estén perfectamente alineados también compensa las aparentes diferencias cronológicas de otros eventos menos importantes en los 100 años subsiguientes.
Probablemente en el año 536 hubo una erupción volcánica en algún lugar en el trópico, de la magnitud de Tambora en 1815. Se ha especulado con que fue una erupción del volcán Krakatoa (anterior a la de 1883), pero esta especulación es incierta, así como las numerosas consecuencias atribuidas a éste evento, como la caída del Imperio Romano o el surgimiento del Islam. Sin entrar en mucho detalle al respecto, esta cita de Michael de Syrian indica, dramáticamente, el potencial que tiene el clima y eventos volcánicos como éste para arruinarle el día a cualquiera:
“El sol estaba oscuro y su oscuridad duró 18 meses; cada día brillaba por cuatro horas, y aún así ésta luz era una sombra débil… los frutos no maduraron y el vino tenía sabor a uva ácida.”
2 March 2008 at 17:47
Nice!
But following up on Michael the Syrian, do green grapes make sour grape wine?
2 March 2008 at 17:50
Makes you realize how devastating such an eruption would be today.
2 March 2008 at 18:08
I am sure everyone has read Sir James Lovelock’s recent interview in the March 1 edition of the Guardian in the UK, written by Decca Aitkenhead, but if somehow you missed it, it is a must-read and also NSFW:
http://www.guardian.co.uk/theguardian/2008/mar/01/scienceofclimatechange.climatechange?gusrc=rss&feed=networkfront
2 March 2008 at 18:59
Looking at the references which appeared along with the report in NATURE about the ice cap over Baffin Island, I noticed one about the 1453 CE event.
Gao, C., A. Robock, S. Self, J. B. Witter, J. P. Steffenson, H. B. Clausen, M.-L. Siggaard-Andersen, S. Johnsen, P. A. Mayewski, and C. Ammann (2006), The 1452 or 1453 A.D. Kuwae eruption signal derived from multiple ice core records: Greatest volcanic sulfate event of the past 700 years, J. Geophys. Res., 111, D12107,
doi:10.1029/2005JD006710.
That event was quite large and also appeared to have resulted in a rather large climate impact. The historical information from China suggests major crop failures and famine. One of the interesting aspects of this report was the differences in dates for an event which might be considered well dated in historical records, even though there were no reports from the actual location.
I’ve also seen references to an event dated at 1259 CE, for which, last I heard, the location had not been determined. Apparently, the Baffin Island data places this event at a somewhat later date.
2 March 2008 at 19:59
This event is well known from the long bristlecone record as well. For those interested in a good treatment of volcanism over the last 50 centuries should look to a paper by Salzer and Hughes last year in QR. Here.
Here is what they have to say on the subject:
The improved dating of the ice core records via the layers is crucial for zeroing in on these large global events. I’m glad to see that this is moving forward.
2 March 2008 at 20:13
Beautiful. I was kind of rooting for the comet (I’m a sucker for astrophysical causes) but this is just as good. Any idea how we go about searching for the culprit volcano?
2 March 2008 at 20:43
The report on the Baffin Island ice cap wasn’t in NATURE, as I mentioned above, but in the GRL. Here’s the reference:
Anderson, R. K., G. H. Miller, J. P. Briner, N. A. Lifton, and S. B. DeVogel (2008), A millennial perspective on Arctic warming from 14C in quartz and plants emerging from beneath ice caps, Geophys. Res. Lett., 35, L01502,
doi:10.1029/2007GL032057.
2 March 2008 at 20:49
And so another one bites the dust.
IIRC the cooling related to this event has been used as the main benchmark separating the “Roman Warm Period” from the later “Medieval Warm Period,” which in the absence of enough data on vulcanism were imputed largely to inferred variations in solar irradiance along with various other minor climate regimes of the last few thousand years.
What’s interesting is how little attention this recent shift in the science has gotten (to the point that I for one had more or less missed it, although it was right there in the AR4 WG1 report).
2 March 2008 at 21:30
Anyone interested in looking at a list of major eruptions over the past 12,000 years should look here:
http://www.volcano.si.edu/world/largeeruptions.cfm
2 March 2008 at 22:16
I would not rely on my memory, but there are 2 events that may be related. One is an asteroid impact that wiped out a city in the ancient world and the other was a volcano on an island in the eastern Mediterranean. The asteroid was in something by John Lewis, maybe his book, “Mining the Sky,” but I’m not sure. I hope this helps your search.
3 March 2008 at 2:33
There is an excellent book by historian David Keys, who covers the global consequences of this volcanic event. It is called “Catastrophe: An Investigation into the Origins of the Modern World”. (Published in 2000.)
3 March 2008 at 5:11
Re 3, Jim certainly deserves a knighthood, but he doesn’t have one yet!
John Gribbin
3 March 2008 at 5:41
Re #3, Ah what a nice picture he paints Mr Lovelock but his statements are starting to sound like the alarm bells that James Hansen is sounding. Mr Hansen as director of GISS (realclimates boss I believe)has recently in january 2008 started issuing warnings of safe limits for CO2 of 350 ppmv which is of course impossible to achieve in the present global economic economy, well unless we can mobilise ourselves to a level of magnitude that dwarves the second world war mobilisation. Oil copanies are not going to stop providing and producing oil, nor are coal companies coal or gas copanies gas but strategic targets by governments could be set but not 120% of CO2 reductions by 2020/2030 as is being requested here.
Hansen states that new paleoclimatic evidence leads him to believe that this is teh case and that 450 ppmv is an absolute upper limit but one that coms with enourmous consequences such as desertification and areas of uninhabiatability across the globe. Maybe Lovelock is right, be prepared to adapt for technology can be devised to do that rather than mitigate CO2 emissions as we can start from a clean slate. Build nuclear power plants to provide the adaptation energy to power the technology. Huge swathes of lans will be under water and food will probably need to be synthesized within 20 years.
It is all very apocolyptic and very doomey but as it comes from these two then I would suggest that we had better start listening. Science is very conservative and very skeptical and when it comes to AGW, it may not have shouted loud enough long enough.
[Response: FYI. Hansen has no connection whatsoever with RC. - gavin]
3 March 2008 at 7:22
What’s the interpretation for the bigger peak (A.D. 529)?
3 March 2008 at 8:20
So without derailing the conversation on the actual topic, what is the prevailing opinion on Lovelock and his current thinking? I’m asking from my position as a layman on the topic of Global Warming. Is he out there? Is he the extreme opinion? Or is there some truth to what he says? This is the second article I have read about Lovelock in the last couple of months, and just wondering how much of what he says is informed science, and how much is not?
3 March 2008 at 8:36
Sigh! There’s still the odd skeptic in the woodpile I see. I’m afraid you lot are becomming increasingly ‘ODDer’ and rarefied…reason…The OVERWHELMING information that ‘PROVES’ ACC is happening. These are the world’s top, most repected scientists, each one experts and masters in their respective fields..each one has spent the best part of thier lives in the quest to understand how their chosen aspects of science works and interrelates to the other earth sciences. These silly little sceptics armed with all their weath of imaginary intelligence and doctorates seem to think that ALL these brilliant and searching minds have it ALL wrong..why dont you take a long hard look in a mirror so you can see how stupid and ridiculous you sound. I bet you dont work in highrise buildings either because some ‘expert’ of an architect built them and so with just the right wind speed and precipitation and relative humidity etc. they could suddenly come crashing down. So stop advertising your abject ignorance and actually listen to what the IPCC is telling you and accept the consequence that raising the most important greenhouse gas by 30%+ in the relative blink of an eye is having on our climate.
3 March 2008 at 11:41
Without commenting on whether Lovelock’s assessment is correct in its various aspects, I am most struck by the logical inconsistency in his message.
On the one hand he states, “Global warming has passed the tipping point, and catastrophe is unstoppable.” As a consequence of that assessment he dismisses ideas such as renewable energy, recycling, avoiding flying etc. as pointless.
And yet, he strongly advocates using nuclear power as something that “can solve our energy problem.”
Well, why is saving CO2 emissions by using nuclear power important, but saving emissions by other methods a waste of time because it is already too late?
Such an inconsistency, it seems to me, renders his message incoherent.
PS. Sorry this is off topic. I did enjoy the 536AD tale, but then got distracted by #3!
3 March 2008 at 11:47
Lovelock is a bit of an eccentric crank.
Six and a half billion people on the planet, soon to be nine or ten billion people on the planet, and he is suggesting that these people shouldn’t bother to recycle or plant trees. Not very credible.
He’s also suggesting that technological nations should give every third world nation and jungle militia’s access to nuclear technology.
The gentleman had some great ideas, but the warranty has expired.
3 March 2008 at 12:04
Lawrence,
There is nothing we can do! If I change all my light bulbs to low energy ones, will that save the world? If I sell my car and get a bicycle will that do? What if you join me, can we save the world together? I think not. Even if all the sensible people in the world stopped wasting energy, there is still another 90% who would go on driving the SUVs, jet skis, and monster trucks. Apart from macho men, how are the few remaining housewives going to get the food to feed their families? They need their car to take them to the supermarket to fetch the groceries.
Our only hope is that the next president of the USA will organise the world to take action. But any presidential candidate who advocates the actions needed will never get elected.
Let’s face it, GWB admitted that the USA is hooked on oil. Our only hope is if we (USA, UK, Europe, China, India, etc.) go cold turkey. Can you see that? Can you see any of the main three (good) candiates advocating that. Can you see them implementing it?
Lovelock’s advice was to enjoy yourself while you can. Why should it be that those who are destroying the world should be the ones to have thh fun?
Cheers, Alastair.
3 March 2008 at 12:08
Just thinking a bit more about the Baillie hypothesis, and also Jim G’s comment (#6) above, it doesn’t follow that we are looking for one event or type of causation, nor should we assume that discovery of a volcanic influence disproves a cometry cause, since the latter would not necessarily leave a crater or impact zone. For example, one might consider a combination of vulcanicity and a major cometry burst, somewhere in the upper atmosphere, the latter leaving a large quantity of dust or volatiles (maybe including SO2?) to be circulated in the stratosphere.
Regarding Edward G’s comment (#10 above), Edward, are you thinking of the eruption of Thera (now called Santorini) when you refer to an island in the Mediterranean? If so, I think the date for that has been fixed pretty well at about 1550 B.C. or thereabouts, so the dates do not match for this as a cause (1550 BC vs 536 AD). Do you know of any other Med. eruptions around 540 AD, as there are a number of other possible culprits, otherwise we shall probably have to look farther afield (e.g. Krakatoa, or maybe something in the southern hemisphere?).
3 March 2008 at 12:38
For a broad overview of reconstructing past climates, including creating an accurate chronology and how the different proxies are combined with models, see:
Walker M and Lowe J (2007) Quaternary science 2007: a 50-year retrospective. Journal of the Geological Society, London, vol 164, pp. 1073-1092.
We are nearly at the stage of having annual climate and environmental data over the last few thousand years and extending into prehistory. Events such as volcanic explosions are very useful for correlating different climate proxies. Written records are an under-exploited source of past climate information, in my opinion.
To jbroon: Lovelock emphasises the worst possible outcome. The main reason for doubting more mild forecasts of climate change is that they fail to adequately consider feedback mechanisms (tipping points). A recent assessment of the dangers of specific tipping elements in the climate system is:
T. M. Lenton, H. Held, E. Kriegler, J. W. Hall, W. Lucht, S.
Rahmstorf, H. J. Schellnhuber (2007) Tipping elements in the earth system. ICESM Abstracts, Vol. 1, ICESM2007-A-00032.
(Tim Lenton has worked with James Lovelock and Stefan Rahmstorf is a contributor to a certain climate blog.)
Lovelock’s worst case scenario is definitely possible, but by no means certain, and while he may turn out to be right about the broad outcome, I for one do not agree with his views on energy and agriculture. For instance, nuclear power will obviously be part of the world’s future energy mix, but the expansion required to cover all our future needs is unlikely and risky in its own right, whatever the drawbacks of lifestyle change and renewable energy. It would also probably be fair to say that he enjoys scaring the cccp out of hapless interviewers, and it is easy to forget how widespread is the requirement on paid scientists to speak in measured terms or risk their job. James Hansen, because of his senior scientific post, can speak out while only running the risk of contradicting political bosses (who can’t argue with him on the science) as opposed to scientific superiors who might take a different view from him and cut off his grant money.
In the UK, politicians are examining whether to increase the 2050 emissions cut target from 60% to 80-90%, so the Hansen view of the science is filtering through.
3 March 2008 at 13:36
#13 Pete Best, having read much of Hansen’s published work and all of Lovelock’s Revenge of Gaia, I really don’t see Hansen and Lovelock’s alarm as being about the same consequences. Lovelock is much more pessimistic.
#17 Slioch, Lovelock’s fear now is that what is coming will be so massive we (in the UK) must be as self-sufficient as possible. He’s quite clear about his reasons in the article, and if he’s right about what’s coming it makes strategic sense.
I don’t know what to make of Lovelock, I think he’s probably overestimated the impact. But his top down arguments appeal to the electronics graduate in me, my fear is “For want of a nail” type cascades. I hope people in 2100 will be able to look back and say “It could have been worse, just look at 536AD.”
Thanks for another interesting essay Gavin.
3 March 2008 at 13:48
Thanks to Ian for the great link in 9.
These look like the best candidates, judging only on proximity to 536AD:
PAGO - New Britain, C 530 AD ± 150 years, VEI 5
VESUVIUS - Italy, 536 AD, VEI 4?
RABAUL New Britain, C 540 AD ± 100 years, VEI 6
3 March 2008 at 14:01
On the subject of Lovelock’s interview, a couple of thoughts come to mind. One, a person should have more modesty than to dismiss the thoughts of someone with one of the world’s greatest minds. Second, one shouldn’t expect too much consistency in a topic as complex as climate change.
Besides, Lovelock doesn’t argue that renewables wouldn’t be beneficial, rather that they’re not practical because of the enormous manufacturing and construction effort required for them, compared to their output. Elsewhere he has pointed out that their part-time nature requires that backup energy be available. So one supposes that if the backup energy were environmentally sound there’d be no point in having the renewables.
My own view is different, but I’d hesitate to disagree with Dr. Lovelock. I think it will take a mix of renewables and nuclear to minimize the problem.
3 March 2008 at 14:05
From
http://www.volcano.si.edu/world/largeeruptions.cfm
suggested as a reference by Ian Forrester in comment #9,
here are some suspects:
PAGO New Britain C 530 AD ± 150 years 5
VESUVIUS Italy 536 AD 4?
RABAUL New Britain C 540 AD ± 100 years 6
But even Rabaul has only a VEI of 6 and the dating is uncorrected radiocarbon (as is that for Pago).
3 March 2008 at 14:18
More reading:
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1600-0889.2005.00131.x
Supporting evidence from the EPICA Dronning Maud Land ice core for atmospheric CO2 changes during the past millennium
Tellus B, Volume 57 Issue 1 Page 51-57, February 2005
Click the link there to follow forward:
Search ISI for citing articles (12 or more)
Among those citing articles, this is interesting:
The early anthropogenic hypothesis: Challenges and responses
Ruddiman, William F.
Source: REVIEWS OF GEOPHYSICS 45 (3): Art. No. RG4001 OCT 31 2007 Document Type: Review
Abstract: Ruddiman ( 2003) proposed that late Holocene anthropogenic intervention caused CH4 and CO2 increases that kept climate from cooling and that preindustrial pandemics caused CO2 decreases and a small cooling. Every aspect of this early anthropogenic hypothesis has been challenged: the timescale, the issue of stage 11 as a better analog, the ability of human activities to account for the gas anomalies, and the impact of the pandemics. This review finds that the late Holocene gas trends are anomalous in all ice timescales; greenhouse gases decreased during the closest stage 11 insolation analog; disproportionate biomass burning and rice irrigation can explain the methane anomaly; and pandemics explain half of the CO2 decrease since 1000 years ago. Only similar to 25% of the CO2 anomaly can, however, be explained by carbon from early deforestation. The remainder must have come from climate system feedbacks, including a Holocene ocean that remained anomalously warm because of anthropogenic intervention.
3 March 2008 at 14:23
In the late 1970s and early 1980s, there were many speculations that a full-scale nuclear exchange would create a “nuclear winter” - but the science at the time relied on simple models, and aerosol effects were poorly understood, so there were many unanswered questions. For a modern take on the question (which is similar to a volcanic eruption in some respects), see:
Robock et. al, Nuclear winter revisited with a modern climate model and current nuclear arsenals: Still catastrophic consequences, JGR 2007
The modern update isn’t any more encouraging, but it does mean that the effects of aerosols, particulates like dust and smoke, are now far better understood, giving more robustness to climate model predictions.
The Pinatubo eruption of June 1991 also provided a rare modern-day test case for climate models. See:
Global Cooling After the Eruption of Mount Pinatubo: A Test of Climate Feedback by Water Vapor, Soden et. al Science 2002
Potential climate impact of Mount Pinatubo eruption, Hansen et. al GRL 1992
Radiative Climate Forcing by the Mount Pinatubo Eruption, Minnis et al Science 1993
So, why does this slightly obscure topic matter? Quote:
3 March 2008 at 14:28
Abbe Mac
Going fossil fuel cold turkey would mean economic suicide.
If you want to see misery, death and destruction, then implement
the nonsense proposed by Gore and Co.
Fortunatelly, it won’t be allowed to go that far. When people start paying through the nose for this hysteria, they’ll use their votes run ya’ll out of town.
Already with the high energy and food prices, we’re beginning to see social instability.
3 March 2008 at 14:30
@Solem
How do you explain Jan 08’s massive global temperature drop?
3 March 2008 at 14:44
Pierre Gosselin Says:
“How do you explain Jan 08’s massive global temperature drop?”
Pierre, how do you explain massive global temerature raise in ‘98?
3 March 2008 at 14:54
Pierre Gossilin (29) — You mean, back to average? Here are some links to proper analyses of recent temperatures:
http://tamino.wordpress.com/2007/12/16/wiggles/
http://tamino.wordpress.com/2007/08/31/garbage-is-forever/
http://tamino.wordpress.com/2008/01/09/dead-heat/
http://tamino.wordpress.com/2008/01/24/giss-ncdc-hadcru/
3 March 2008 at 15:09
Re #12: Oil copanies are not going to stop providing and producing oil, nor are coal companies coal or gas copanies gas but strategic targets by governments could be set but not 120% of CO2 reductions by 2020/2030 as is being requested here.
Oil companies have an absolute financial incentive to continue driving oil ever further into scarcity. With today’s new record of $104/bbl, once can see the scarce oil is a lot more valuable than if we reduced demand by conservation.
Re: #28: Going fossil fuel cold turkey would mean economic suicide.
If you want to see misery, death and destruction, then implement
the nonsense proposed by Gore and Co.
I’m already personally “carbon positive” (or whatever is better than “carbon neutral” and I’m not going broke. The people who go broke are going to be the ones who, like my DI1K (double income, one kid
) friends who likely gross north of $150K and “can’t afford” a hybrid.
Economic suicide is what people do when they persist in buying new cars that run on gasoline. Which the car companies would love people to do since we’re going to be forced to by yet another brand new car when our gasoline bill exceeds our new car payment.
ObTopic: Fascinating stuff. I remember when Pinatubo blew up and the sky slowly changed from infrequent red sunsets to the far more common just about every day sort of red sunsets. I’ve been waiting ever since for “Red sky in morning, sailors take warning. Red sky at night, sailors delight” to have some manner of predictive ability.
3 March 2008 at 15:15
#28 I dont think cold turkey on fossil fuel is even remotely feasible within a 30-50 year span, but Gore wasnt advocating that - rather a whole series of small measures which together bring down CO2. You can use your votes to live in a pretend-world where global warming isnt happening but that wont stop temperatures rising. Can we put your country down for say 2 million refugees? You think anti-CO2 measures will cause instability but that nothing on what climate change will bring. Oh, and every natural cycle is still working bringing ups and downs with it. Will you scream global warming has stopped with cycle or look at the long term trend? Note also the prediction that 2007, 2008 would be steady (and thats without the La Nina) but 2009 would see business as usual.
3 March 2008 at 15:16
Re Pierre’s question in 29:
How do you explain last night’s massive global temperature drop?
3 March 2008 at 16:09
How do you explain Jan 08’s massive global temperature drop?
Answer - Weather
The one degree F in global heating is not going to eliminate winters, for cying out loud.
3 March 2008 at 16:28
RE: comment #25 (quoted below):
Huyanaputina in 1600 also had a VEI of 6, so Rabaul would seem to be an excellent suspect (caldera-former). Vesuvius seems unlikely.
“suggested as a reference by Ian Forrester in comment #9,
here are some suspects:
PAGO New Britain C 530 AD ± 150 years 5
VESUVIUS Italy 536 AD 4?
RABAUL New Britain C 540 AD ± 100 years 6
But even Rabaul has only a VEI of 6 and the dating is uncorrected radiocarbon (as is that for Pago).”
3 March 2008 at 16:31
FurryCatHerder (32) — Biopact
http://biopact.com/
calls what you have accomplished carbon-negative.
Congradulations!
3 March 2008 at 16:51
Another point in Rabaul’s favor is that the caldera formed in the 540 +/- 100 event was flooded by the sea (this contributes greatly to aerosols):
http://volcano.und.edu/vwdocs/volc_images/img_rabaul.html
Note that the caldera encompasses the whole bay–the more obvious volcanoes are smaller vents around its periphery. These have been known to erupt simultaneously in recent years–exciting place to live!
3 March 2008 at 17:10
I have heard of the Krakatoa theory accounting for the 536 eruption. In his book “Krakatoa”, Simon Winchester used anecdotal evidence to claim that there was an eruption of the devilish island that helped the peasants of Sumatra overthrow their abusive rulers. Winchester then used the 1883 to help account for the overthrow of the Dutch in Indonesia and the rise of Islam in the region to its current. Its a very interesting read if you are not familiar with geology.
3 March 2008 at 18:02
Great post.
RE Lovelock & wind power. He lives out in the countryside, where they are proposing to build massive wind farms, which would destroy the view & kill birds. I think Robert Kennedy Jr (with Natural Resource Defense Council) is also opposed to wind for the same reasons.
As one on 100% wind I do feel a bit guilty that birds get killed and my power source may be ruining someone’s country view out in West Texas.
Maybe over time inventors will come up with wind and solar solutions that are smaller and less obstructing, ones households could employ to generate all their electrical needs (which could be reduced through efficiency/conservation measures, green building, passive solar, etc), and also use that electricity for recharging their EV or compressed air EV, so they could drive on the wind or the sun. That would mean living off-the-grid, freedom from the matrix.
Oh yes, I forgot, we’re already there. The tech is available.
Now, if we could just get the government to cut back on those huge subsidies and tax breaks to oil and coal….which we pay for on April 15th, regardless of whether we’re off the grid and driving on wind/solar power.
3 March 2008 at 18:10
It appears that the weather events were world-wide:
http://en.wikipedia.org/wiki/Climate_changes_of_535-536
and that the hypothesis of Rabaul was already made in 1984.
(The problem with Krakatoa is that there is no definitive evidence of a super-eruption in the years in question.)
3 March 2008 at 19:26
Re #14
The bigger peak in 529 could be the one corroborated by the DML cores. 529 is within the range 542 +/- 17.
3 March 2008 at 19:29
#24: Linus Pauling was one of the 20th century’s finest. Two Nobels in his own right (granted one not for science), and a whisker away from another with the DNA structure. Yet in later life he was plain wrong about vitamin C - to the point of nutty - though his standing meant that many assumed otherwise (some still do!).
Lovelock is wrong about nuclear and wrong about renewables. He misses the power of distributed generation. Photovoltaics on every roof and a grid extending across time zones are all that’s needed. Do-able now and affordable now. Four decades (to 2050) will be more than enough to get it done.
3 March 2008 at 19:50
Lynn Vincentnathan (40) — … my power source may be ruining someone’s country view out in West Texas. I’m sure that out there they think the view improved.
Regarding bird strikes, I am under the impression that this is not (much of) a problem for the newer, slower turning, windmills.
3 March 2008 at 20:07
I’ve read the book Catastrophe by David Keys. The central theme is the 535-536 AD event was a volcanic eruption. Keys’ conclusion, based partly on local evidence, is that the culprit was Krakatua, and the 535-536AD eruption was more severe than the 18th century one.
Re. 3. Lovelock is a defeatist, although he claims to be an optimist. He does tend to blow his own trumpet - he attributes himself more prescience than I think is warrented. And it’s all very well for him to “Enjoy life while [he] can”. He’s 88.
On the other hand, I’m a pessimist. I doubt we’ll adequately deal with global warming before it starts to hurt, at which point more and greater pain is inevitable. In this case the cost will be huge, but saying we’ll be reduced to a single “breeding pair in the arctic” is delusional.
Yet I believe that it is possible for us to avoid the worst, although some effects of climate change are now inevitable. I just don’t believe we’ll do it - too many vested interests. However, I’m determined to do my bit to help minimise the damage.
Re 9 The list of major eruptions in the alst 12,000 years is clearly incomplete. Half occur after 1000AD and 25% after 1800AD. It’s very easy to image a few VEI 7s (i.e. Tambora-sized eruptions) being missed.
3 March 2008 at 20:45
Pierre Gosselin claims that trying to address global warming (GW) can only be done cold turkey? Get real. NO one, and I mean NO major scientist or Government or major agency has ever claimed that we must go cold turkey on all oil/coal power sources to solve GW. So what is the person’s point besides stupid alarmism to attack other peoples ideas? Yes, there is a range of options that people propose, some more aggressive then others but none even remotely that extreme but to make a false straw man to attack GW and other people’s thoughtful idea’s is a typical, immature response to an otherwise intelligent forum.
3 March 2008 at 21:39
RE: Volcano Tours
For all the latest info on volcanos and tours to them: GO: http://www.volcanodiscovery.com. Lots of useful info here. If you happen to have a few grand in spare change, a tour to a volcano would be a really nice alternative to the standard vacation to tropical resorts. Be prepared to rough it, however. The tours go out to the volcano where you camp out for 4-5 days while you explore the volcano and hike around the area.
What’s really interesting is the list of active volcanos. Pretty scary since any one of them could undergo a major eruption, like The Son of Krakatoa.
3 March 2008 at 22:20
Re: Abbe Mac..it’s true what Pierre says that suddenly going cold turkey will be economic suicide. We cant go cold turkey anyway..the infrastructure just isn’t there and wont be for decades. We can’t even decide upon a tough carbon trading scheme. We are still stuck in the committe level of progress. Logically I share your sentiments but I also realise that I must do my level best as well- I’ve got a 2 year old son who deserves a decent future. Either way our ship has reached the other reaches of one hell of a hurricane..a ‘perfect storm’ whether we come out the other side or not depends on our united stewardship..not many disparate captains pulling the ship in all directions. We have to realise also that whatever we do to mitigate CC we will still get sucked helplessly towards the eye of the storm..it’s going to get progressively worse and worse for a hundred years or more and the oceans for another thousand plus.. What we do need ‘NOW’ is definite emmission goals set by every country. I believe the world bank will have to compensate poorer countries to meet their short/medium and long term goals. We must also allow flexibily in those goals as well..as more up to date reports in the future from the IPCC and other bodies saying we must do more to but the brakes on..this must be heeded by world govs to bring forward their goals…there is going to be an enormous economic cost..not too many are denying that..but what’s the point of maintaining a robust economy if the world’s dying?
3 March 2008 at 22:51
13: I personally thought Lovelocks predictions 2020 and 2040 to be beyond the pale doomster stuff. I think I understand Hansen, and I don’t think he says that post tipping point feedbacks would be anything near that rapid. Hansen is more concerned with what will happen in say 50 to a few hundred years.
I don’t think we are looking for a super-eruption. My understanding of the term is that supereruptions are Yellowstone or Toba sized events involving roughly 1000 KM**3 magma. The world probably only sees a supereruption about once per hundred thousand years. 536, is probably much less significant.
3 March 2008 at 23:45
Why does the presence of sulfates rule out impacts (iceballs or hardballs)? I mean I understand reasonably well enough that volcanic eruptions produce sulfur compounds that would show up in the ice cores. But why couldn’t an impact produce the same compounds? Massive fires of either peat or forests resulting from an impact would seem to create similar releases of sulfur. From the massive fires over Indonesia recently - we saw the impact of that on the atmosphere.
I’m not questioning the conclusion - purely interest on my part. I’ve always had a passing interest in the time period - from Arthurian legends, collapse of civilization, Plague of Justinian, etc. And so whether or not the critical event of 535-6 was a comet or volcano would seem interesting - I’ve always been fond of the theory that a comet struck Western Europe.
4 March 2008 at 0:43
Robin, I think — I’m not an expert, I just did a quick browse of what Google Scholar offers — that the distinction is based on the quantity of sulfur. I can’t think of any source that would produce a really large amount from a meteor or from a biological source hit by one.
Just a quick look found me this quantity estimate for example:
http://www.sciencemag.org/cgi/content/abstract/209/4459/923
“During the steady-state period of activity of La Soufriere Volcano in 1979, the mass emissions of sulfur dioxide into the troposphere amounted to a mean value of 339 ± 126 metric tons per day. This value is similar to the sulfur dioxide emissions of other Central American volcanoes but less than those measured at Mount Etna, an exceptionally strong volcanic source of sulfur dioxide.”
I don’t know how many days those volcanos were in steady-state activity, but the total adds up fast.
4 March 2008 at 1:09
RE#48 “We cant go cold turkey anyway..the infrastructure just isn’t there and wont be for decades.”
Try http://www.nytimes.com/2008/02/05/science/earth/05city.html
“Car-Free, Solar City in Gulf Could Set a New Standard for Green Design.”
and
http://www.time.com/time/specials/2007/article/0,28804,1712863_1712864,00.html
“Renewable Energy: Desert Dreams”
Thus, the time required to transition to a renewable energy basis could be measured in years rather than decades - it’s all a matter of how many resources are devoted to it.
4 March 2008 at 3:32
#29 # Pierre Gosselin asked
“How do you explain Jan 08’s massive global temperature drop?”
Firstly, remember that January 2007 was the warmest January on record (anomaly 0.87C NASA GISS), so that obviously amplifies the current fall. (Jan 2008 0.12C)
Secondly, there is presently a strong La Nina (negative temperature anomaly) in the Pacific (caused by an upwelling of colder water from the depths). The cooler waters of the Pacific absorb large amounts of heat from the atmosphere and are probably (partly) responsible for the cold events witnessed recently in many parts of the world.
La Nina events are the flip side of El Nino: during the latter the Pacific surface waters become abnormally warm. An El Nino event was responsible for the positive spike in global temperatures in 1998, and we appear at present to be getting a negative spike from this La Nina in 2008.
Here are graphs of sea surface temperatures in the Pacific for Feb. 7th 2007 and Feb. 8th 2008. The lower graph in each set is the interesting one since it shows the anomaly relative to 1971-2000:
Feb. 7th 2007: http://www.emc.ncep.noaa.gov/research/cmb/sst_analysis/images/archive/weekly_TPAC/tpacv2_20070207.png
Feb. 6th 2008: http://www.emc.ncep.noaa.gov/research/cmb/sst_analysis/images/archive/weekly_TPAC/tpacv2_20080206.png
If you doubt the cooling effect of La Nina, try taking a hot-water bottle filled with cold water to bed with you!
Finally, Tamino’s articles (linked to in #31 above) should settle any remaining doubts you may have about if we are now experiencing global cooling: we are not.
4 March 2008 at 4:25
James Lovelock is being more visionary than scientist in the quoted interview. When asked
Put the 2020 and 2040 dates on one side and his views on the possibility of future disaster are not substantially different from James Hansen. The difficulty is that he has a track record of being on the mark with earlier, seemingly wild forecasts. Perhaps we should file these predictions but not forget them.
The interviewer tells us
and
Even if he’s right then to fulfil his hope, we will need renewable sources of power. Nuclear can only be a temporary expedient in his scenario.
4 March 2008 at 5:55
From the reports from Rome on the 535 event it would appear fairly certain that the present food supplies would fail totally with anything like that scale of impact on insolation. An aggressive natural disaster of the cataclysmic kind we don’t need right now. There are quite enough convergences in the pipeline.
The recent cold snap at ground level will play havoc on food production. What is the impact of the southern USA weather on corn production? With USA producing about 8% of its fuel from corn and with the now-solid relationship between food and fuel any reduction in the corn harvest will increase the stress between food and fuel supplies – the oil shock of a few decades ago was only a 5% dip in supply.
I think Lovelock is right in his general view. I admire the way Hansen et al say that everything will be sort of OK if only we can do X, Y and Z. But we wont and it is becoming increasingly clear that we cannot. So while Hansen et al are correct in their estimate of what is needed to keep us safe; their comments about “all we have to do is…” are simply to keep them in the loop as part of a socially acceptable run at the solution.
I agree that we might as well stop messing about with mitigation. For example we have no idea how to sequester CO2 at any sort of commercial scale that would make a difference. There will be twice the volume of liquid CO2 as there is oil and handling that amount of CO2 product is impossible. The infrastructure will never be built, and if it does it would require twice the energy input to the system to get both the current energy output and the CO2 sequestered. Biofuels don’t add up – or rather they do:– to more CO2 than fossil fuels. Carbon taxes wont be spent anywhere useful, etc etc… Its all rubbish.
But like Lovelock I think there is hope for a great adventure. Like the start of war there will be the opportunity for euphoric pursuit of new goals and new systems that will – to a degree – see the survival of some of us. We wont be building tanks or fighters – we will be building sustainable power supplies, local MASH units, self contained farms and running railways around the 100m above sea level contour to provide a simple old-world transport route that will last past the time the seas stop rising.
There will be opportunities for good old commercial interests to prevail in the production and operation of new systems. But the old systems will surely fail. Energy and food are now inextricably intertwined, and we will find – perhaps before the middle of this year – that the world will move into a hoarding phase where citizens and nations start building stores not as short term buffers against variations in commodity prices but as reserves for the long term future – until until.
The variations in climate, the stagnation in oil production, the increased demand for food, the imposition of export levies in numerous countries to halt export of foodstuffs, droughts and climate extremes, trembling commodity markets, failing banks, collapsing ice sheets, melting glaciers and the increased rate of extinctions in amphibians, insects, sea life and small mammals (not to mention the coming demise of our primary predator the Polar Bear!) are all indicators of a convergence of forces against the survival of modern society in its present form.
In the main any opportunity for useful control of these forces has already slipped beyond the control of any man or country.
For those of us left standing these will definitely be exciting times! It will indeed be “…life Jim, but not as we know it!”
4 March 2008 at 6:19
Re #49, Yellowstone is every 600,000 years and one is over due by 40,000 years I believe. As for Lovelock, I agree that his message appears very starck but he sees earth science differently to te majority. For one he is a true systemesist and laments the lack of the true complex modelling in terms of the biosphere as well as physical processes which he belieevs is sigificant.
His predictions are based on additional factors which makes them more dire than the majority of climate scientists but who is to say that he is not right rather than misguided.
Re. Re#13, Sorry RC. I i no way meant to associate James Hansen with RC, only with GISS.
4 March 2008 at 6:31
Pierre Gosselin writes:
[[Going fossil fuel cold turkey would mean economic suicide.]]
True. We’ll have to do it gradually, say, in a couple of decades.
[[If you want to see misery, death and destruction, then implement the nonsense proposed by Gore and Co.]]
What nonsense would that be?
[[Fortunatelly, it won’t be allowed to go that far. When people start paying through the nose for this hysteria, they’ll use their votes run ya’ll out of town.]]
The contraction is “y’all” from “you all.”
[[Already with the high energy and food prices, we’re beginning to see social instability.]]
We’ve seen social instability for a long, long time.
4 March 2008 at 8:01
Robin Johnson, Having been near both volcanos and forest fires, I can say without a doubt that forest fires cannot touch volcanos for production of sulfur. Sulfur melts at a relatively low temperature, and so will dissolve into the superheated water associated with a magma body. When pressure is released by the eruption, it will flash to vapor and react with the water to form sulfuric acid and other sulfates as it is dispersed at high altitudes–even into the stratosphere.
Forest fires, because carbon is the dominant element, tend to form a lot of CO2 and ash. Not the same at all.
4 March 2008 at 8:28
Re: 46. You’re wrong! Our Gov in australia has just been advised rather strongly by a leading and respected economist Prof. Ross Garnaut about the economic impact of global warming and he advocates just that. well..a 90% reduction in greenhouse gasses by 2050 anyway. More and more reports are coming in saying that the only way to stabilise climate and then reverse the damage done is by going almost completly carbon neutral ASAP. Sorry DBrown..get your facts straight first!
4 March 2008 at 8:50
Just read a bio of James Lovelock’s life and achievements..what an incredible man!! His insights into life itself and the atmosphere as an extention of everything that has ever breathed to me were based on buddhism..well I’m buddhist so I’m biased..hehe! We wont destroy the earth..only us and virtually every animal and plant on this planet for a heck of a long time. The earth WILL recover maybe in a million years..but it will recover!
Here’s the link of one of his bios…http://www.rollingstone.com/politics/story/16956300/the_prophet_of_climate_change_james_lovelock/print
4 March 2008 at 8:55
Thanks Hank and Ray.
4 March 2008 at 9:30
On the subject of renewables:
There really is very little reason we can’t do more to deploy renewable sources of energy. The incremental cost is measured in pennies per KWH, and the total cost differences in many instances is dollars per month. For some sources, such as wind, there is now a financial incentive to use wind rather than coal — the “all wind” electric plans here in Texas are fractionally cheaper than the mixed coal-nuke plans.
I wish I could say my electric costs are going down, but at something like 300KWH for January (they misred my meter last month by 100KWH, so I’ve not updated the image the link off my name references, but last month was 408KWH or so according to them), that monthly customer service fee starts to show up in the cost of electricity as pennies per KWH.
On the subject of distributed generation:
Sorry, not a solution. I’d love it if it were, and the solar array on my roof would also love it if it were. But, alas, I have the graphs of power output to prove that distributed generation is a really BAD idea. What distributed generation is a good idea for is surviving the coming problems the electric grid is going to face as ever increasing amounts of load are shifted from carbon-based to electron-based sources. I’m not interested in being without electricity because 1/3rd of the population decides to plug their electric cars in on a Sunday night so they can drive the next day and the grid collapsed because the load exceeded that of the hottest summer afternoon.
Distributed generation is needed so we can survive the end of the oil era, not so we can cut carbon emissions at the coal-fired plants. ERCOT, the grid where I live, produces somewhere around 35GW on a day like today — maybe a bit higher if we dip below freezing tonight. But 35GW is a whopping 18 nuclear plants at 2GW each. Toss in some landfill natural gas or landfill reclaimed biomass powered generators for frequency and voltage regulation and all of Texas is off the carbon addiction for electric generation. Time to realize that? Ten or 15 years. Doubt my math? You can check the ERCOT load / generation numbers at http://mospublic.ercot.com/ercot/jsp/frequency_control.jsp . Current generation — 39,400MW.
The solution isn’t distributed generation, which has to be the dumbest idea anyone ever dreamt up (yes, really — managing ERCOT is no simple feat. Imagine all 17 million or so Texans all poking their fingers in ERCOT’s interconnect), it’s large scale storage technologies such as compressed air and pumped hydro. Several more GW of wind out in West and North Texas, pump the Lower Colorado back into the Highland Lakes during the periods of high wind, or air into salt dome down south, and we’ve got our regulation abilities from wind sources.
The main obstacles are not the techology. The entire automobile fleet is already being replaced on a shorter timescale than we have to end our oil addiction (I’m a “we can’t cause global warming because we can’t afford the price of fossil fuels” skeptic, for those of you who don’t know me). We know how to build electric motors. We know how to build batteries. Toyota’s system (Hybrid Synergy Drive) is now very well proven and leds itself to conversion to plug-in hybrid. All that remains is the will to pull the trigger, and people don’t want to give up their giant oil swilling SUVs or their cutsie dimmable lights to avert what, for themselves, is going to be a financial disaster.
4 March 2008 at 10:17
George Monbiot has got it in the best perspective. He says small is not beautiful anymore. It will take a gargantuan effort such as Iceland developing enough thermal generating facilities to power nearly the whole of Europe. Do-able but far off.
Think of how much electricity Yellowstone could produce (don’t think too much about that super eruption though, cause no one knows how to avoid that. In my dreams I see Bill Gates buying a hundred automatic drilling machines placed 20 miles away drilling a low angle to intersect the magma chamber well below center, and slowly venting it). Sorry for getting off topic.
Here is Monbiot’s speech in Aug. ‘07 at the Camp for Climate Change in London. He is the second speaker in at approx. 15 minutes. Best keep the volume down. It was recorded from the audience and their applause is quite loud.
http://www.indymedia.org.uk/en/2007/08/379803.html
4 March 2008 at 11:16
I’m not sure what James Lovelock’s doing in this thread, but since he does not appear to be going away, I fear I must dissent from the general tone of reverence. There’s no doubt Lovelock has considerable achievements to his credit, but he’s far from infallible in his judgements on environmental matters - as he, again to his credit, recognises (in “Homage to Gaia”, 2000). A pioneer of measuring trace atmospheric gases, in 1974 he declared that the CFCs in the atmosphere posed “no conceivable hazard” (Lovelock, J.E., Maggs, R.J. and Wade, R.J. (1973). Halogenated Hydrocarbons in and over the Atlantic. Nature ‘241, 194-196). More generally, he was for a long time very confident of “Gaia’s” ability to deal with human-caused pollution - a confidence which I am sure was quite sincere, but was very convenient to the large companies, such as Shell, who financed his work. The “Gaia Hypothesis” is certainly brilliant, if only as a “meme” extraordinarily well adapted to its cultural environment. Aitkenhead’s interview says Gaia theory “forms the basis of almost all climate science”. I do not know whether Aitkenhead acquired this view from Lovelock, but I would be interested in the contributors’ views on the statement itself. The interview also makes clear that Lovelock makes absolutely no effort to limit his own GHG emissions or other impacts on the environment.
4 March 2008 at 11:50
A smart grid ensures that people don’t overload the grid at any particular time. Set the price high enough, and people will find different times to charge their cars.
4 March 2008 at 12:42
RE #48 “what’s the point of maintaining a robust economy if the world’s dying”
That got me thinking, we really don’t have a robust economy, if we’re consuming & destroying the capital. It’s like selling the building and machines of a factory part by part. On the books it looks like we’re making a good profit, but once the capital is all gone, there will be a collapse. And I’m just speaking of using up and polluting finite resources, on which economies ultimately depend. If you include the effects of GW, the situation is even more dire…..like you sell the roof of your factory, which makes your books look great for the moment, then the next moment a flood and hurricane strike and destroy an even greater portion of your capital, plus killing some of your workers. Then you have to sell all the more capital to cover up the losses.
We’re in the midst of a close-out fire sale, which simply gives the illusion of a robust economy.
4 March 2008 at 13:24
Re. #58 (Ray L.) Ray, do we have any data on comets releasing SO2, just pursuing the air burst (as opposed to full impact) idea? Or would they produce other volatiles that might have the same climate effect as that indicated in the c. 536 AD data?
4 March 2008 at 13:50
You are right. Not a super-eruption:
http://volcano.und.edu/vwdocs/eruption_scale.html
http://www.geolsoc.org.uk/gsl/education/page2970.html
4 March 2008 at 14:49
Nick O., We have to ask where the sulfur would come from. There is no process I can think of for a comet to be particularly enriched in sulfur. So, it would have to be a direct hit on a site on Earth where sulfur was enriched. You might have a somewhat high sulfur content in a bog, but there would be lots of organic matter to burn along with it–not the sort of event we’re looking for. For high-sulfur/low-organic, you are looking at a geologically active area with lots of hyhdrothermal activity (e.g. Rotorua in N. Zealand or Yellowstone in the US). Such sites are a lot more likely to supply their own explosive potential rather than requiring a cometary impact.
4 March 2008 at 17:43
This topic ought to make anyone thinking of the global engineering strategy of injecting aerosols into the stratosphere, to mitigate the effects of AGW, give it another look and go back to the drawing board.
If we overshoot the planned upon levels of sulfates and the fruits and other food products don’t ripen, at our current levels of population, for a season or two, we’re in big trouble.
4 March 2008 at 19:20
RE: Age of Fossil Fuels Will Last Forever!
I have said this many times here and elsewhere, I will say this once again here, and I will say this at RC for the very last time. We will always use increasing amounts of fossils fuels because there are no subsitutes with the requisite chemical and physical properties, and there never ever will be any reduction in the emission of carbon dioxide.
For example, boats, planes, freight trains and trucks, construction, mining and agricultural machines, most cars and light trucks, motorcycles, snowmobiles, ATV’s, all military vehicles, go-carts, golf course and sports field grass mowers, etc will require and use liquid fossils fuels becasue these fuels have high energy density and are easily prepared from crude oil by fractional distillation and blending, low energy processes that do not require the breaking of chemical bonds. Even catalytic cracking of heavier distillate fractions is a low energy process.
The “Fuels of Freedom” are chemically inert (except to reaction with oxygen. halogens and several highly reactive chemicals such as singlet oxygen) noncorrosive, highly portable, and can be stored indefinitely in sealed containers (e.g., steel drums) and under an inert atmosphere (e.g., nitrogen) in large tanks.
Fossils fuels will always be required for lime and cement kilns, metal smelters, steel mills, foundries and metal casting plants, metal cutting and braising torches, all factories that make ceramics (e.g., bricks, tiles, china, glass, etc), all food production, processing and distribution, space and water heating, cooking and baking, BBQ’s, manufacture of porcelain-coated metals, harvesting of wood and lumber manufacture, isolation of essential oils by steam distillation for prepartion of fragrances and flavors, etc.
The reasons we use thermal plants for generating electricity is that these plants have a small footprint, can be located close to consumers, and produce electricity reliably and at very high energy-densities.
Fossils are the feedstock for the petrochemical
industries (sometimes called the chemical process industries), which manufacture everything from A to Z, such as synthetic fibers. There is not enough suitable land for growing cotton, flax and sheep to meet world demand.
If you guys have any schemes that will replace fossil fuels for the above applications and uses, I’m quite sure the engineers will glady welcome your suggestions.
We will always have lots of fossil fuels because we can always use coal for manufacture of synthetic hydrocarbons. Germany did this on amassive scale during WW II and South Africa use the process and it supplies about 40% of liquid hydrocarbons which can be
manufactured into a wide range of useful materials.
Google “SASOL” for more info.
4 March 2008 at 20:42
Well, I have no doubt that every last barrel of oil, ton of coal, and cubic meter of gas will be extracted as soon as commercially feasible, no matter the harm to the environment, but…”always” ? That’s hard to picture.Always is such a long time.
4 March 2008 at 20:50
Re 60 Lawrence Coleman,
My understanding is that going “cold turkey” means you immediately stop doing something, in this case using carbon based fuel sources.
A reduction or 90% in the per-capita CO2 emissions over the 42 years between now and 2050 proposed by the Garnaut Review here in Australia is not the same as “going cold turkey”.
Yes it’s a rapid transition, but the idea is to use our current sources of wealth and energy (fossil fuels) to leverage us into new sources of wealth and energy, just as has happened whenever the form of energy that underpins society has changed.
4 March 2008 at 21:03
Re Harold Pierce @ 71: “I will say this once again here, and I will say this at RC for the very last time. ”
Is that a promise?
4 March 2008 at 21:16
Re 64 Nick Gotts.
I agree on Lovelock. His recent book “The Revenge of Gaia” was probably the most unscientific book on global warming I’ve ever read, with the possible exception of Michael Crichton’s State of Fear. The books are from opposite ends of the spectrum, but only one pretends it is not fiction.
He is justly famous for the Gaia Hypothesis, which has led to Earth Systems Science. But he continues to encourage the religious overtones of the concept, that Gaia is somehow teleological or purposful. And the concept that Gaia is a homeostatic organism, striving to maintain a constant environment is over the top. A better concept might be a broad scale corollary of Le Chatelier’s Principle: that when an equilibrium is disturbed the equilibrium shifts to partially counteract the change. There is nothing unique to living systems about this behaviour.
4 March 2008 at 21:33
Re 71 Harold Pierce,
I could go through and refute your argument case by case, but ultimately what you have said is a statement of religious belief, and one that is demonstrably a mathematical impossibility. On a planet where we “will always use increasing amounts of fossil fuels” the “Age of Fossil Fuels” cannot possibly last forever, as the reserves of fossil fuels are finite - even coal, oil shales, tar sands etc. This is even more the case when you consider EROI - energy return on investment. The only fossil fuels that are worth recovering are ones that ultimately yield more energy than they cost to recover and process for their ultimate purpose.
4 March 2008 at 21:41
Harold Pierce, Jr., According to the World Coal Institute: “At current production levels, proven coal reserves are estimated to last 147 years.”
That assumes current production levels, but of course energy demand will continue to grow. I had hoped that forever would be further off than 1.5 centuries. So, when the coal runs out, do you propose to mine Titan?
Fossil fuels are finite. They threaten the continued viability of civilization. Accept it and let’s find a way to cope without them.
4 March 2008 at 21:48
Re 55 Nigel Williams,
I largely agree. You have the optimists view of what I view with great pessimism. To me “interesting times” - war, famine, depression, genocide - are better read about in books or perhaps seen from afar. Unfortunately we will be building tanks and fighters as this is an inevitable response in times of stress like this, along with the rise of tyrants and demagogues. A world population crash to around 1 billion, which is a realistic worst case, will not be pleasant for the 6-7 billion “missing”. Will the survivours consider they have lived through “interesting times” or a holocaust, as that is the only comparable magnitude of loss - the almost complete loss of European Jewry.
On a minor point, I think you’ll find that 65-70 metres is the highest retreat needed and quite possibly only 12-25 metres will be required, but picking where sea level will stabilise will be difficult.
4 March 2008 at 22:24
Harold, Re 71,
Just for sh*ts and giggles try googling Peak Oil and Peak Coal.
4 March 2008 at 23:26
As stated in Hansen 1981, and elsewhere, one of the main tenents of AGW is that as the atmosphere becomes more opaque the effective radiating level will rise and that because of the lapse rate will emit at a lower temperature, I suppose assuming that that level stays within the troposphere. In 1981 Dr. Hansen put the height at 6.5km/5.5km for tropics/poles. First, I would like to know where he got this number, was it by calculation or observation. And secondly, it has been 25 years, has that level moved higher? Or if that is an ill formed question, at what height did the earth emit from before we perturbed the natural order?
Thank you for any insight.
[Response: It’s based on the mean emitting temperature (i.e. the T at which SB emission would equal absorbed solar) which is around 255 K. If the mean surface temperature is 288 K and the lapse rate is around 6 K/km then you end up with a mean emitting height of 5 to 6 km. This does not mean that this is where all outgoing LW comes from - you can see from the spectra that for different wavelengths the emissions come from different temperatures (heights) - that is of course how satellites can sense different parts of the atmosphere. Since it is a little bit of a convenient fiction, changes in this height are more useful as a pedagogic device than as a tool for diagnosing climate change. - gavin]
5 March 2008 at 1:27
It would be nice if the AGW Catastrophists could actually measure some observations that give credence to the Hypothesis of Anthropogenic Global Warming…. That shows it has a SIGNIFICANT effect and affects climate. To the extent that it is clearly visible beyond the background noise of natural variation…. they can’t.
So… Ten years now, there has been no warming trend. Despite the Hypothosis that Increasing CO2 drives warming… Now we have a cooling…. No mechanisms explained… Nor for the 40’s until 70’s cooling period either…
We also just happen to have the lowest activity of sunspots…
Sunspot activity makes a better fit than does Athropogenic CO2.
Trying to fit Volcanoes into your bits and pieces here is not going to help… We’ve had large modern eruptions and a heap of data from them… The effects don’t stay in the atmosphere for any significant period.. The affects would not last centuries… What about St Helens and Pinotubo…
5 March 2008 at 2:13
Re #75 Bruce Tabor
My suspicion is that the Gaia Hypothesis is just a special case of the Anthropic Principle: the Earth appears to have all these self-restoring tendencies because we are around to talk about it
That doesn’t guarantee that it will last though, does it. A world population crash due to a sudden collapse of the agricultural production base, somewhere in the 2030-2060 time frame, is a worst case scenario, but unfortunately not one that seems entirely over the top — most people have no idea of the fragility of the ecological base of our production system.
And when comparing with the Holocaust you’re missing three orders of magnitude.
5 March 2008 at 7:14
Nigel Williams writes:
[[For those of us left standing these will definitely be exciting times! It will indeed be “…life Jim, but not as we know it!”]]
What makes you think you or your descendants will be among those left standing?
5 March 2008 at 7:56
Harold Pierce Jr writes:
[[We will always use increasing amounts of fossils fuels]]
That’s physically impossible. There aren’t infinite amounts of fossil fuels. Using increasing amounts means the more we use, the faster we run out. Do you understand how a compound-interest expansion works?
If the entire upper 10 kilometers of the Earth’s surface were pure anthracite, and use rises 2% per year compared to this year’s equivalent of about 3.9 x 1012 kilograms equivalent, we run completely out of fossil fuels in 688 years (and God knows what the surface temperature of the Earth would be like by then). If, a little more realistically, only one part in 1,000 is fossil fuels, we run out in 339 years. Either way, we run out.
5 March 2008 at 10:13
Re J.Hansford @ 81: “It would be nice if the AGW Catastrophists could actually measure some observations that give credence to the Hypothesis of Anthropogenic Global Warming….”
Such measurements have been addressed here at RealClimate repeatedly, as has been your assertion that there has been no warming trend for ten years. Don’t blame others for your inability to pay attention.
J.Hansford: “Sunspot activity makes a better fit than does Athropogenic CO2.”
Then how, exactly, do you explain the divergence of sunspot activity from temperature rise after the late 1970s?
What you fail to understand is that solar variation and greenhouse gases are entirely separate and independent phenomena that may offset or reinforce each other. Should solar activity lessen, cooling of Earth’s surface and atmosphere will result, but greenhouse gases will continue to make it warmer than it otherwise would be. Likewise, any increase in solar insolation will be amplified by greenhouse gases. Either way, adding more greenhouse gases will make it warmer yet.
5 March 2008 at 11:20
RE: 536 eruption
“here are some suspects:
PAGO New Britain C 530 AD ± 150 years 5
VESUVIUS Italy 536 AD 4?
RABAUL New Britain C 540 AD ± 100 years 6″
Instead of a single, massive eruption, would a series of smaller, closely spaced eruptions have the same effect? Would all of the particulates from the first be cleared by the time any smaller “after-eruptions” came by?
The list above shows two smaller eruptions within 10 yrs (I know, there’s a +/- 150 yrs). How much would have been in the air when the second one, IN THE SAME AREA, went off? Or a second one “down-wind” of the first?
Speaking of the “dating”, would particulates from two, closely spaced (time and location) eruptions compound the dating errors?
Just curious.
5 March 2008 at 12:39
“Instead of a single, massive eruption, would a series of smaller, closely spaced eruptions have the same effect? Would all of the particulates from the first be cleared by the time any smaller “after-eruptions” came by?”
I suspect that it needs a big one, sufficient to put a lot of particulates and water in the stratosphere where it will linger for years, small ones will wash out of the troposphere much more rapidly.
5 March 2008 at 12:52
Note: Volcanic eruptions of any type can be treated as Poisson events. The probability of having 2 in close succession will generally be small. Moreover, a large volcanic eruption is more efficient at throwing material high into the atmosphere, where it stays longer and has more effect.
5 March 2008 at 12:58
RE: #74
Yep! I promise! And not only that, I’m not going to rebut my critics.
I’m wasting too much time on these climate blogs. I still have to process about 100 temperature records from my favorite weather station and lightstation at Quatsino, BC. I just finished a multi-decadal analysis of the min temperature for Fall Equinox Interval (FEI, Sept 16-26) and have obtained some inexplicable results. Here is a brief synopsis. The data are reported for the mean min temp +/- AD, where AD is the classical average deviation. The results are: 1900-29, 280.5 +/- 1.5 K; 1930-89. 281.8 +/- 1.5 K; and 1990-2005, 283.1 +/- 1.5 K.
The temperature jump of 1.3 K between the intervals is significantly different by the t-test (p less than 0.05). I compared the yearly means for each decadal interval on either side of the jump point using the t-test for unpaired data. I have no explanation for the long intervals of constant temperature for the 1900-29 and 1930-89 intervals. The total jump of 2.6 K applies only to this interval and not to the Spring, Summer and Winter intervals (i.e, 11 days centered on the soltice or equinox). I didn’t do a multi-decadal analysis on these intervals. However, I did compare the 1900-06 interval to the 2000-06 interval for min temperature for these four sampling intervals, but I still working on this for the max temp. I still have to do the multi-decadal analysis for the max temp for the FEI to see if the temp jumps occurs for this metric. So stayed tuned for more “hot” results from the Pierce Climate Research Center (aka the basement rec room!).
Attn: Gavin! Is it OK to do a t-test on the yearly means for each decade when comparing two decades or do I have punch in 110 numbers (Groan!) for each data set? Please don’t say, “No!” BTW, I will send you hard copy when I get this project done.
5 March 2008 at 13:08
Is there a reason why Europeans are so shy in declaring 2 consecutive none winters? Surely something which was read about the medieval warm period, from my Euro contacts it was/is quite astounding. What is remarkable about 536 AD event is that it was reported in Europe, also recorded by trees in Arizona, a truly world wide phenomenon, an easier to explain climate event. With retrospect this past winter shows climate in its true esoteric nature. , as some contrarians are celebrating what they call an extremely cold winter, an end of a long spell of NH warming. Climate is not so simple, does not turn on an impredictable dime, it has many 3 dimensional facets transposed in a time morass.
5 March 2008 at 13:59
Re J Hansford @ 81 wrote: “…No mechanisms explained… Nor for the 40’s until 70’s cooling period either…”
No mechanism only if you have blinders on or refuse to look for it. The mechanism is likely simple. 1998 was an anomalously warm year due to ENSO. This year is shaping up to be anomalously cool, also likely to ENSO. Reasons like these are why “climate” is averaged over many years, and is not based on a cherry picked start date. Weren’t you talking about background noise a moment ago? And then you go on to cite a short cycle! The 40’s-70’s were explained by increasing fossil fuel sulfates and other aerosol particles at that time.
Re J Hansford @ 81 wrote: “…Sunspot activity makes a better fit than does Athropogenic CO2…”
Then why don’t we see a significant trace of an 11 year periodicity in global temperatures? Check out what temps were doing 11 years ago when we were at a similar place in our solar cycle. Temps were rising. What happened to your imaginary sunspot correlation? If you knew much about sunspots and the current (semi-popular in skeptical circles) theory of GCRs you would know that Svensmark would expect the exact opposite correlation that you seem to from the sunspot cycles. Funny thing…his expectations don’t seem to correlate with measured temps either….
5 March 2008 at 14:08
henry (86) — Even the super-eruption of Mt. Toba about 74–71 kya left sulfates in the stratosphere for only about 3, perhaps 6 years. Tambora (VEI 7) produced a single year without a summer.
So to obtain eighteen months of effects, the hypothesized two or more eruptions need to be one right after the other, so to speak. But yes, this might be the best accounting for the observations that we can have, baring more evidence. Nicely thought out, thank you.
The dating is via radiocarbon. Unless one eruption causes fires in the forests of the other, I fail to see how the datings could be confused.
5 March 2008 at 14:36
RE #78 & “65-70 metres is the highest retreat needed”
About how long (how many decades or centuries) would it take in a worse case scenario for the sea to rise 60 meters? I need this info for a story I’m writing.
5 March 2008 at 15:26
What I got from this article is that it reinforces my belief that the primary threat from climate change is in our ability to produce food; sea level rise and other effects are merely add-ons.
Most people in the developed world have no idea how sensitive farming is to weather patterns, because they aren’t farmers. Farmers are pretty good at optimizing what they can get from the land under the weather patterns they have adapted to locally. Almost any difference from ‘normal’ weather patterns will result in less food production. The devil in climate change is not the periods of equilibrium at either end; it’s the period of instability in the middle.
We’ve all become concerned about the price of fuel; we’ve no idea what it will be like when the price of a loaf of bread becomes a significant portion of your income. If you are reading this, you are affluent enough to afford a computer and an internet connection and that pretty much means that getting enough food is not a daily struggle for you.
From a very broad term perspective, fossil fuel energy is merely solar energy that has been stored. In the long run, the earth’s people are limited to the energy coming into the system, and that means solar, or its derivatives, wind and wave. (Or possibly geothermal or fusion, that would last a blessed long time if we can ever get it figured out, but then there would be only food production and living space to limit our population and the end result of that doesn’t have a good feel to it either.) Solar energy will not sustain the current world population at the level required by our industrialized societies. Eventually, something will have to give; either the world population decreases or our energy consumption dramatically drops. With current and foreseeable technology, a dramatic drop in energy use would mean a lot of people die; there is connectivity there. It’s very close to a catch 22.
Paranoia warning, read on at your own risk.
Do you think that the current administration is all stupid? I don’t think so. Do you think that they are power hungry? I think almost all people who seek positions of authority are. Do you think that they weren’t aware a few years ago that a continued military presence in the middle east would likely cost them the coming election? They must have been aware of the risk. So, what really motivated the war(s) and has kept us there? I don’t know, but it had to be more important than ensuring the politicians’ positions of power. It wasn’t WMD and it wasn’t bringing democracy to the region. My prediction is that whoever wins the election will have access to information they currently don’t, and we will stay. Best guess: Whatever nation has control over the most (energy) resources will be at a significant advantage in the coming decades.
“May you live in interesting times.” is a curse, not a blessing. There will be tanks and planes. I fear for my children’s future.
5 March 2008 at 16:27
henry, I’m no expert, but looking quickly with terms I recall, there’s been a lot of work done identifying the chemicals and isotopes that can tell one layer of volcanic ash from another — they can be traced back to specific volcanos, by what’s in them, very often.
This is quite an old cite but if you click the ‘citing sources’ link on the page it’ll lead you forward following other papers that referred to it, and you can see some of how this area of science developed:
http://arjournals.annualreviews.org/doi/abs/10.1146/annurev.ea.16.050188.000445
5 March 2008 at 20:00
Volcanic Eruptions Cool the Earth - Yeah, We Knew That
Regarding Henry’s post, I would be much more impressed if we could account for the Little Ice Age with volcanic events.
This eruption I heard about through PBS (I think) a few years ago in a show on the Keys book. It’s nice the time scales on the ice cores can be lined up. Nevertheless, we are talking about a blip of few years of cooling.
So this doesn’t amount to anything like disproving solar variation as a cause of some climate change as some posters have seemed to suggest.
5 March 2008 at 20:14
The site is great and I enjoyed the post about the 534 anomaly. Unfortunately, the “(more)” link doesn’t work in Firefox 2. I was forced to use IE instead. For reasons I don’t understand, this comments feature doesn’t work in Firefox. My apologies for posting this here, but I couldn’t find anyplace else.
Cline
5 March 2008 at 23:19
Lynn 93. Reading between the waves, Hansen is betting on multi-metre rise by 2100 - especially if we do BAU, and even if we do get back to 350ppm CO2 in the next few decades.
I understand Greenland ice sheet is 8m of sea rise, West Antarctic is 7m rise gives a first round total of 15m. The other 55m comes from the rest of the Antarctic ice sheets plus glaciers etc. That gets us to around +70m above present high tide. After that there will be on-going thermal expansion of the ocean until we (oops we wont be here will we) until Mother Earth reaches thermal equilibrium. Probably (unless I am contradicted) +80m is a good number to look at for the new high tide mark. I believe if you are planning any sort of ‘sustainable’ structure you shouldn’t get closer than +100m, as the process of the coastal hills settling down to a natural angle of repose will take a while, and depending on slope will chew the cliff-edge back quite a way.
How fast? Well emissions will slow a bit as we die off, but its unlikely we will get away with less than 450ppm CO2 as a peak because there will be a bit of a flurry of emission-related activity as we try and build our way to some sort of safe future using our existing infrastructure. Faint hope. But 450ppm and the combination of peak oil and peak food will see demand ease in say 50 years, and anything like BAU will see all the predicted social turmoil of climate and sea level rise refugees heading for the pie shop on the top of the hill. The rise will happen in a sine-wave style - slow at first (we’re seeing the beginning of the beginning now) increasing to a peak rate of change as we pass thru about +30 to +40m, and then slowing as the decreased volume of ice remaining contributes less per year.
So if we get +5m by 2100 (perish the thought) then a sketch of 80m on a sine-like curve finds 5m at about 25% of the time (100 years), so peak at 50% (the next 100 years). So peak rate of rise is at around 2200CE, and then you are looking at maybe 5m in 20 years. Draw the curve yourself and see how it looks to you. If its less by 2100 (say only 2m) then that flattens and extends the whole thing. We hope. Since the tail will be due to the warming of the deep ocean the tail will be very long - millenia. So it will probably be C4000CE before coasts will start to settle down and develop, and once again shallow water shell fish, coastal spawning grounds and the like will begin to re-establish. In the intervening period the coastal waters will be a turgid mess of freshly eroded land swirling among rough bedrock and collapsing sea-cliffs. As the fishing reports say - it will definitely be ‘muddy and un-fishable’ for quite a while.
5 March 2008 at 23:58
#80
As a follow up to Gavin’s response for further clarification, the tropopause has actually increased in height (See for example Santer et al, Science, 2003; 479-483). This reduces the stratosphere, and so you get much more cold air above you to radiate downward. If you did want to confine an “Effective radiating level” to a single altitude though, it would be much lower than the tropo-strato boundary anyway. If you increase the height of the effective radiating level, you extrapolate along a greater distance using the appropriate adiabiat and the surface is warmer.
6 March 2008 at 7:14
in #93 Lynn Vincentnathan said:
During the sort of interglacial period that we currently inhabit, if the Eemian example MIS-5e is any guide, 2°C suffices to raise global sea level for the next hundred years and many centuries to come by an average of 1.6 meters, or about 5 feet, per century. That may be the best case that we can, on average, expect. During MIS-5e, some centuries suffered a sea rise rate higher than average, others a lower; a few centuries knew some stability or even a sea level drop.
The worst sea rise rate I can recall seeing in studies of paleoclimate is 5m per century but such a rapid rate has never been sustained for more than two centuries as far as I know. However, the worst-case total sea rise may be worse than you think, closer to 80 meters than 60. Either way, getting there at the 1.6m rate would obviously take a few thousand years. Hope that helps!
6 March 2008 at 7:20
Re. 93 Lynn Vincentnathan, 65-70 metres
The most rapid known rise in sea level occurred at the end of the last ice age during the so-called Meltwater Pulse 1A. I’ve seen various estimates, but a typical one is a 25 metre rise in 500 years or 5 metres per century, 0.5 metres per decade.
http://en.wikipedia.org/wiki/Image:Post-Glacial_Sea_Level.png
The actual forcing that triggered this was small compared to current climate forcings - initially only about 0.25 W/m^2 - we currently have 0.75 +/- 0.25 W/m^2 and rising. Somehow this initial trigger led to the build up of GHG’s and albedo changes (and more forcing) that resulted in this rapid rise in sea level. I don’t know exacly how soon after the trigger it occurred, I suspect it’s unknown.
You could theoretically calculate a maximum rate based on climate forcings and some albedo feedbacks, and an assumption of how much of the forcing went into melting ice. Let’s assume 100% of the forcing went into melting ice.
Lets say 1 W/m^2 forcing - thats 5*10^14 W over the globe.
The latent heat of melting for water is 334J/g or 3.34*10^17 Joules/km^3 water equivalent - i.e. water volume once melted.
Over the whole globe over a year, 1 W/m^2 corresponds to:
1W/m^2*(500*10^6km^2)*(1*10^6m^2/km^2)*(3600sec/hr)*(24/day)*(365day/yr)=1.58*10^22Joules
Dividing these two results gives:
1.58*10^22Joules/3.34*10^17 Joules/km^3=47,000km^3 melted water per year.
This is distributed over 350 million km^2 of ocean
47,000km^3/350 million km^2=0.13*10^-3km/yr=0.13 metres per year.
(For comparison each of Greenland and West Antarctica is estimated to be losing about 150 km^3 per year, for a combined sea level rise of a little under 1mm per year.)
So if all that 1 W/m^2 forcing went into ice melting it could raise sea level by 1.3 metres per decade or 13 m/100yrs. This is unlikely in itself as a good proportion of heat must go into warming the ocean, although this may stop if large amounts of ice spread through the oceans as ice sheets break up - creating an efficient way to transfer heat from ocean to ice, which incidentally is half of the key to the whole process - the other half being albedo changes on the ice itself (eg. meltwater ponds, soot), which transfer heat straight to the ice.
If you wanted to speed things up for fictional purposes you could double the forcing due to albedo changes, eg loss of the polar sea ice, formation of large meltwater lakes on ice. You could then add release of CO2 and methane from permafrost. In addition, in some areas, especially West Antarctica, the ice won’t need to melt - it will just flow off the surface it rests on once enough lubrication and buoyancy is present - this could happen in a decade or less (5 metre rise). Almost as rapid collapse is possible in Greenland - 7 metre rise. The stable ice sheet is East Antarctica - equivalent to about a 55-58 metre rise.
In short, I’ve no idea of the maximum possible rate. I could believe extreme conditions could do it within a century, but a number of worst-case positive feedbacks would have to be present.
What do others think?
6 March 2008 at 8:22
J. Hansford writes:
[[So… Ten years now, there has been no warming trend.]]
Not true. Look again:
http://members.aol.com/bpl1960/Ball.html
[[ Despite the Hypothosis that Increasing CO2 drives warming… Now we have a cooling…. No mechanisms explained… Nor for the 40’s until 70’s cooling period either…]]
Industrial aerosols.
[[We also just happen to have the lowest activity of sunspots…
Sunspot activity makes a better fit than does Athropogenic CO2. ]]
No, it doesn’t, actually. There’s a fairly good relation between solar activity and temperature up to about 1940, but sunlight has been essentially flat since 1950, so it can’t explain the present sharp upturn in global warming.
6 March 2008 at 8:41
Well, scientists are often myopic too. Really. Some latch onto something they are certain is rock solid and then tectonics or KT gets reasoned and evidence observed, and the raft floats around and the sky occasionally falls, and catastrophic terminations and punctuations rule.
Gavin, and Ray Pierre know clearly and well enough that there is an effort to fund and seriously study the “Sulfate Aerosol Shield,” and more and more people are starting to realize this workable scheme will be supported by Big Carbon Inc., with lots of money, since it would “allow” much more CO2 to be pumped and dumped in the Commons of our Air, as Ray noted, in Science article quote. NCAR has done recent work. As well as a solid body of “modeling.”
http://sciencenow.sciencemag.org/cgi/content/full/2008/222/1
The “quote” probably Ray to Eli Kintisch in a phone interview. . .
http://www.agu.org/pubs/crossref/2008/2007GL032179.shtml
The Work.
Paul Crutzen is Author #2, above paper.
You can do this in your head.
Viz.
Pulverize to 1 micron thickness a cubic meter of sulfur. That single pulverized cubic meter of sulfur will cover a million square meters of stratosphere surface and it would take ~555 billion cubic meters to make a 1 micron thick sulfur shield over the entire earth. If a pre-pulverized cubic meter of sulfur weighs a ton (density ~1) then 1.5 GtS, could make an aerosol shield 3 microns thick, and cool the planet enough to counteract some of the global warming for a while. That would get you lots of Big C Inc. funding.
Ray points out that once started there is a global stability issue, and a maintenance issue that lasts a long time. I do NOT like the shield idea, without a simultaneous mechanism to suck 10 to 25% of the atmosphere into a device to remove and sequester the CO2. Nature can’t do this or we would not have AGW.
Lag Time
The “lag” time for 385-390 ppm CO2 thermal equilibrium with its 25 F temp rise is 143 years (according to Carl Johnson, who computes the length of time it takes to use air to heat a column of rock 3000 feet deep, to the temperature 83F) Carl’s wrong “of course” (but where?) and the rise is only . . .?
http://mb-soft.com/public3/global.html
(This is the website that needs holes punched in it, legitimate holes with straight-forward physics. )
This line of analysis, leading to some real disturbing conclusions, is part of why James Hansen is hawking 350 ppmv. (I favor 300 ppmv)
No Matter. The rate at which the new equilibrium is approached, and its value, can be argued (The rate.) But the final temperature is an issue to all of life on earth. Hmmm, “issue” is understatement.
Poke some honest reasonable holes in Carl’s approach. Please. (Ignore his 1353, Solar constant from way B.C. I thought the ocean could moderate, but water vapor only may not be enough. Aerosol shield any one?)
I don’t know if the image here will make it into the comments section, but here is an illustration of a global “sulfate aerosol shield” that reflects 70% of incident solar irradiance, and keeps the temp down to about 900 F. uniformly. Of course, there is some CO2 that keeps the temperature that high.
The 536 AD event is relevant, especially WRT the agricultural output. Too cold or too hot? The deniers need rope for support. The real point is this: The system is critically balanced. WE humans have screwed that up. We have the rope, not the will. Sea change coming. Billions die. Species time could be over. But doesn’t have to be.
6 March 2008 at 9:06
Re. 93 Lynn Vincentnathan,
Further to my earlier comments. Prehistorically, sea level rise at the end of glacial periods was rapid, in contrast to the slow build up of ice sheets over tens of thousands of years. Current GCMs almost certainly do not capture the break-up of ice sheets accurately. It has become obvious that ice sheet collapse is a rapid, nonlinear and “wet” process. Rapid breakdown in the past coincided with Heinrich Events, where armadas of glaciers broke off from ice sheet glaciers:
http://en.wikipedia.org/wiki/Hein