A volcanic climate disaster in the Middle Ages?

The Warmists at Real Climate think that there was so there probably wasn't. An extensive look at the evidence below

By Antti Arjava, Department of Classics, University of Helsinki [antti.arjava@skr.fi]

In 1983 Richard Stothers and Michael Rampino of NASA published a list of all ancient volcanic eruptions known from Mediterranean historical sources. Their list included a persistent dust veil or dry fog which darkened the sky for about a year in AD 536--37, bringing about cold, drought and food shortage in the Mediterranean area or, as it has since been claimed, all over the northern hemisphere. Especially following two popular books devoted to the dust veil by David Keys and Mike Baillie, it has been acclaimed as the worst climatic disaster in recorded history. In the most wide-ranging scenarios, the year 536 is seen as a watershed moment between the ancient and modern worlds, bringing about economic decline, population movements, political unrest, and ultimately the collapse of civilizations.

In a lengthy article written in 2004 and just to be published in the Byzantinist journal Dumbarton Oaks Papers I have gone through all the available physical and written evidence for the 536 event. The inevitable conclusion from the ancient literary sources is that the historical impact of the cloud must have been extremely limited. On the other hand, some assumptions about the cloud's physical nature that have hitherto been taken for granted should be re-examined. In the following, I give a brief summary of my paper.

Physical evidence for the 536 event is derived from two main sources: tree rings and acid layers in Greenland ice. The tree rings show 536 and the following ten years as a period of very slow growth for Scandinavian pines, North European oaks and several North American species. However, the contours of a sudden catastrophe cannot be directly read from the tree ring evidence. In many series, the drop in 536 is followed by a recovery in 537--38 and then again by an even more serious plunge. In most cases, the worst years are around 540, and in Siberia 543. In southern Chile, the trough is in 540, while in Argentina there was dramatic growth reduction only after 540, with a minimum in 548. In Tasmania, the tree growth declined between 546 and 552.

Thus, although the year 536 was certainly a very bad growing season in many parts of the world, it is situated in a decade-long downturn in the climate of the Northern Hemisphere and is separated from the really worst seasons by 3--7 years. Moreover, and perhaps even more seriously, in the Scandinavian pines as in the oaks and North American trees, it is possible to see a long-term growth decline during the early part of the sixth century which is matched by an equally slow rise in the average growth during the second half of the century. This would place the years around 540 as the lowest point in a slow climatic cycle. While it does not disprove a climatic anomaly in 536, all this nevertheless suggests that the link between the dark cloud and tree growth is not as straightforward as might be wished. The dendrochronological maxim "trees do not lie" may be true, but neither do they seem to provide unequivocal answers to the questions which historians would like to pose to them.

Historical eruptions are usually attested as acid layers in Greenland ice. In the previously published studies, all the relevant sections of the Greenland ice cores for the mid-sixth century have been either missing, flawed or poorly dated. Recently, Danish scholars have reported that a major eruption can be dated to the early spring of 528. It is unclear whether it might be possible to redate the whole sequence of ice layers by a few years, matching the new attested eruption with the 536 event. Any conclusions therefore must remain tentative, but so far we have to admit that no acid layer sufficient for a major volcanic eruption has been confirmed around 536. That is why the cloud has been attributed to the impact of a comet. This hypothesis is not confirmed by any direct evidence either.

Archaeological evidence does not help us assess the consequences of possible crop failures around 536. Recent archaeological work serves to stress the need for a regional approach: economic and demographic developments may differ in neighboring regions. The whole western part of the Roman empire was in clear decline already in the fifth century. The Persian devastations in northern Syria, combined with recurrent earthquakes and epidemics, would probably suffice to explain any sixth-century economic decline in the Byzantine Near East.

The results of my inquiry into the written sources are relatively straightforward: although the cloud occasioned confusion and crop failure at the time it was seen, its effects did not last long after it had dissipated. Compared with almost all other contemporary civilizations around the world, the circumstances in the Mediterranean area are extremely well documented. The literary sources which record the darkness of 536/7 all seem to consider it a temporary misfortune. Among the innumerable earthquakes, droughts, plagues, swarms of locusts, and slaughters which are listed by the historians of this time, the dark cloud was not counted as a particular catastrophe. Shortage of food was a recurrent phenomenon in the ancient world, and people were used to it, however intense the short-term suffering might be.

For example, two Italian sources, Cassiodorus and the Liber Pontificalis, attest continuing problems with the harvest in 537, which is not surprising if the fog persisted until the summer. Immediate effects of the event are not reported after that. The historian Procopius for his part does not mention the crop failures of 536/7. He says that outside besieged Rome the Goths were also starving, but he rather seems to give the credit for it to a successful Byzantine naval blockade. In contrast, the historian describes at great length a terrible famine in Italy in 539. However, he is quite explicit that it was due to the fields being left uncultivated because of the war. A little later he returns to the subject of food shortage among the Goths, again insinuating that the lack of supplies was a logistic problem. He does not give a hint that climatic conditions might have been blamed for continual bad harvests.

Though these sources leave no doubt that a mysterious fog was seen in an area which extended at least from Italy to Asia Minor and caused bad harvests there for one or two years, they all seem to treat it as a temporary bad omen, not as the beginning of a long period of unfavorable climatic conditions. Of course, the writers might not have noted a slight drop in average temperatures, and might perhaps not have cared to record a change in prevailing winds or precipitation. However, if the direct consequences of such underlying factors for agriculture had been grave enough to undermine the economic well-being of the empire, we would expect somewhat more attention being paid to them by contemporary writers.

Thus, the combined force of the available evidence irresistibly shows that, whatever happened around 536, its historical implications remained very limited, at least in the Mediterranean area. On the other hand, the sources report interesting, though sometimes conflicting, details of the fog. Although the haze has been called a dry fog or dust veil ever since 1984, a passage from the eyewitness antiquarian writer John Lydus which has hitherto been neglected rather suggests that the fog was damp. This is not decisive because it can reasonably be claimed that Lydus may not have been able to observe its actual composition. However, he also asserts that the fog was seen only in Europe, and it is more difficult to discredit this report out of hand. It would be in clear contrast to the common scholarly assumption that the cloud was a global or at least a hemispherical phenomenon. Remarkably, all the other literary sources mention the fog only for an area around Italy and Asia Minor.

Cold and drought are attested in other parts of the world but not the persistent fog. Chinese sources record that the star Canopus was not seen at the spring and fall equinoxes in 536. Although this might be taken to refer to reduced atmospheric transparency (as many scholars have assumed), it seems a rather understated way to describe a darkness which continued for a year. It is especially odd if it was the factor which caused summer frosts, drought and widespread famine, duly recorded in Chinese historical works between 535 (sic) and 538. At least two possibilities emerge: either the Chinese did not mention the fog because opaque skies are not unusual in northern China due to the frequent desert storms there, or the fog was tropospheric and localized in the Mediterranean area. While zonal winds would have spread a stratospheric fog over the northern latitudes within a few weeks or months, a tropospheric fog (volcanic or not) might very well have attenuated before reaching China. The problem remains that no tropospheric fog of such duration has been observed in historical times.

However, if we accept the possibility that the fog may have been seen in northern China though it was not clearly recorded, it might also be possible to explain Lydus' account in a different way. All those areas for which the fog is securely attested (Italy, Constantinople) lie above 35 degrees of northern latitude, perhaps even above 40 degrees, depending on how we interpret Procopius' report. The same is true of northern Mesopotamia (ca. 37ø N). In contrast, those areas further east which Lydus claims did not witness the fog (Persia, India) all lie below 40 or even 35 degrees northern latitude, and this also applies to most of China. Thus, we might actually have a cloud which could be seen only at latitudes north of the Mediterranean and in the very north of China. Such a rather abrupt and globally uniform cutoff latitude falling between 30 and 40 degrees has been observed for stratospheric aerosol veils stemming from large eruptions of northern volcanoes, notably Lakagigar (Iceland, 1783), Ksudach (Kamchatka, 1907) and Katmai (Alaska, 1912). For example, the dust cloud from Katmai was seen and measured at Bassour, Algeria (36ø N), at Simla, India (31ø N) and at two US observatories (34-36ø N), but not at Helwan, Egypt (30ø N).

If we interpret Lydus' text in this manner, disregarding his report of the moist fog and assuming that the missing or misdated acid layers in the ice cores can be explained somehow, it would add a new dimension to the volcano hypothesis. It would actually support the suggestion made by Richard Stothers that the mystery cloud derived from a far northern volcano, and not from a tropical one like Rabaul (New Guinea), Krakatau (Indonesia) or El Chich¢n (Mexico), which have been earlier suspects. The observed decline of tree growth in South America in the 540s might seem to be at odds with this. However, it has not yet been established whether a high-latitude eruption could have global climatic effects. The issue is currently debated.

We cannot check the scientific accuracy of Lydus' reports. They may mislead us, but at the very least they invite us to re-examine the scientific evidence for the event. It remains true that the Greenland ice cores have so far produced little proof of volcanic activity around 536, and that the tree rings are surprisingly ambiguous about climatic variation in different parts of the world between 535--552. Two main alternatives emerge. The dark cloud may have originated from a northern volcano, being visible only at latitudes north of the Mediterranean, or the fog may have been locally more restricted, perhaps damp, originating from a totally unknown source. As a tropospheric fog of such duration would be quite exceptional, the first alternative perhaps seems at present more likely. Further ice cores may prove or disprove it in the future. However, for those who are as of yet not convinced by the volcano hypothesis, the second alternative might appear worth serious consideration.

Source. See also here (Scroll down to third article)




Examination of global warming models urged in light of Argo data

A liberal media outlet has acknowledged that global warming may have "taken a breather." National Public Radio reports instead of warming up over the past four or five years, oceans have actually been cooling slightly. According to NPR, NASA's Jet Propulsion Laboratory has been studying the ocean with a fleet of robotic instruments that can dive 3,000 feet down and measure ocean temperature. Since the "Argo" system was fully deployed in 2003, it has recorded no warming of the global oceans, but rather "slight cooling."

Marc Morano with the Senate Environment and Public Works Committee says the cooling trend runs contrary to the claims of people promoting manmade global warming fears. But NPR -- which he describes as "an entrenched, liberal, mainstream institution" -- would rather question NASA's data, showing no ocean warming, instead of questioning the models that are predicting catastrophic sea level rise due to supposed global warming, he notes.

Morano notes that the NASA study shows there is no major cause for panic about catastrophic manmade global warming. "We're finding it across the board now in recent years as the hypothesis of manmade global warming is starting to collapse around the globe [that] more and more scientists are rejecting it," he states.

Many scientists are actually predicting a possible global cooling in the next half-century, he adds.

"Study after study in peer-review journals is following this study on the oceans and showing the cause for alarm not only is not there, but it's actually the other way," Morano explains. "Many scientists now are predicting a possible global cooling in the next ... 10, to 50, to 75 years, depending on which scientist you're talking to. In fact, many from the Russian National Academy of Sciences are predicting just that."

The NPR report quotes a JPL spokesman who says global warming does not necessarily mean that every year will be warmer than the last. "And it may be that we are in a period of less rapid warming," suggests JPL's Josh Willis. But Morano says something other than global warming is afoot because sea ice has been expanding in the Antarctic since satellites began monitoring it, the Arctic has actually cooled over the last 1,500 years, and even Greenland has cooled since the 1940s.

Source





Perhaps The Climate Change Models Are Wrong?

They drift along in the worlds' oceans at a depth of 2,000 metres -- more than a mile deep -- constantly monitoring the temperature, salinity, pressure and velocity of the upper oceans. Then, about once every 10 days, a bladder on the outside of these buoys inflates and raises them slowly to the surface gathering data about each strata of seawater they pass through. After an upward journey of nearly six hours, the Argo monitors bob on the waves while an onboard transmitter sends their information to a satellite that in turn retransmits it to several land-based research computers where it may be accessed by anyone who wishes to see it.

These 3,000 yellow sentinels --about the size and shape of a large fence post -- free-float the world's oceans, season in and season out, surfacing between 30 and 40 times a year, disgorging their findings, then submerging again for another fact-finding voyage. It's fascinating to watch their progress online. (The URLs are too complex to reproduce here, but Google "Argo Buoy Movement" or "Argo Float Animation," and you will be directed to the links.)

When they were first deployed in 2003, the Argos were hailed for their ability to collect information on ocean conditions more precisely, at more places and greater depths and in more conditions than ever before. No longer would scientists have to rely on measurements mostly at the surface from older scientific buoys or inconsistent shipboard monitors.

So why are some scientists now beginning to question the buoys' findings? Because in five years, the little blighters have failed to detect any global warming. They are not reinforcing the scientific orthodoxy of the day, namely that man is causing the planet to warm dangerously. They are not proving the predetermined conclusions of their human masters. Therefore they, and not their masters' hypotheses, must be wrong. In fact, "there has been a very slight cooling," according to a U.S. National Public Radio (NPR) interview with Josh Willis at NASA's Jet Propulsion Laboratory, a scientist who keeps close watch on the Argo findings.

Dr. Willis insisted the temperature drop was "not anything really significant." And I trust he's right. But can anyone imagine NASA or the National Oceanic and Atmospheric Administration (NOAA) or the Intergovernmental Panel on Climate Change -- the UN's climate experts -- shrugging off even a "very slight" warming. A slight drop in the oceans' temperature over a period of five or six years probably is insignificant, just as a warming over such a short period would be. Yet if there had been a rise of any kind, even of the same slightness, rest assured this would be broadcast far and wide as yet another log on the global warming fire.

Just look how tenaciously some scientists are prepared to cling to the climate change dogma. "It may be that we are in a period of less rapid warming," Dr. Willis told NPR. Yeah, you know, like when you put your car into reverse you are causing it to enter a period of less rapid forward motion. Or when I gain a few pounds I am in a period of less rapid weight loss.

The big problem with the Argo findings is that all the major climate computer models postulate that as much as 80-90% of global warming will result from the oceans warming rapidly then releasing their heat into the atmosphere. But if the oceans aren't warming, then (please whisper) perhaps the models are wrong. The supercomputer models also can't explain the interaction of clouds and climate. They have no idea whether clouds warm the world more by trapping heat in or cool it by reflecting heat back into space.

Modellers are also perplexed by the findings of NASA's eight weather satellites that take more than 300,000 temperature readings daily over the entire surface of the Earth, versus approximately 7,000 random readings from Earth stations. In nearly 30 years of operation, the satellites have discovered a warming trend of just 0.14 C per decade, less than the models and well within the natural range of temperature variation.

I'm not saying for sure the models are wrong and the Argos and satellites are right, only that in a debate as critical as the one on climate, it would be nice to hear some alternatives to the alarmist theory.

Source





Now global warming causes mental illness!

Or so an "environmental philosopher" tells us. I am more inclined to believe that mental illness causes belief in global warming! I have reproduced only the first part of the twaddle below. It is just far-fetched speculation loaded onto some perfectly normal experiences

A small yet growing body of evidence suggests that how people think and feel is being influenced strongly by ecosystem transformation related to climate change and industry-related displacement from the land. These powerful stressors are occurring more frequently around the world. A case in point: When researchers from the Centre for Rural and Remote Mental Health at the University of Newcastle in Australia conducted interviews in drought-affected communities in New South Wales in 2005, the responses suggested some of their subjects may have been suffering from a recently described psychological condition called solastalgia (pronounced so-la-stal-juh).

Solastalgia describes a palpable sense of dislocation and loss that people feel when they perceive changes to their local environment as harmful. It's a neologism that Glenn Albrecht, an environmental philosopher at the University of Newcastle's School of Environmental and Life Sciences, created in 2003. Albrecht's work among communities distraught by black-coal strip mining in New South Wales' Upper Hunter Region convinced him that the English language needed a new term to connect the experience of ecosystem loss to mental health concerns. "The sense of a home landscape being violated [by strip mining-related environmental damage] seemed to have disturbed the region's social ecology so much that the psychic or mental health of many people living in the zone of high impact was being affected," he says.

Albrecht's stunning insight? That there might be a wide variety of shifts in the health of an ecosystem-from subtle landscape changes related to global warming to desolate wastelands created by large-scale strip mining-that diminish people's mental health. In Eastern Australian communities, where the toll of a six-year-long drought has been devastating, interviews with farmers provided additional momentum for the solastalgia concept. In one such interview, a female farmer poignantly described the loss of her garden oasis. "Our gardens have had to die," she said, "because our house dam has been dry.. So it's very depressing for a woman because a garden is an oasis out here with this dust.you know, to come home to a nice green lawn is just. that's all gone, so you've got dust at your back door."

While persistent drought and open-pit coal mining may be extreme cases, if the environmental degradation of the past hundred years is any indication, our contemporary lifestyles, built on a dwindling resource base, have failed to acknowledge how much the mental health of people and ecosystems is interrelated.

This may imply that the unrelenting media focus on weather-related and economic aspects of climate change does not adequately take into consideration the challenge of mitigating the psychological impact of global warming. How might we feel when the heat is relentless and our surrounding environment changes irrevocably? How might our mental health be affected?

In a recent WiredWired magazine article on Albrecht and the concept of solastalgia, "Global Mourning: How the next victim of climate change will be our minds," writer Clive Thompson sensitively characterized as "global mourning" the potential impact of overwhelming environmental transformation caused by climate change. Thompson cogently summed up Albrecht's view of what solastalgia might look like were it to become an epidemic of emotional and psychic instability causally linked to changing climates and ecosystems. Albrecht also emphasizes that feelings of melancholia and homesickness have previously been recorded among Aboriginal peoples in the Americas and Australia who were forcibly moved from their home territories by U.S., Canadian and Australian governments in the late nineteenth and twentieth centuries.

Source







GREEN TRADE WAR: THE WONDER-WEAPON AGAINST ASIAN COMPETITION?

Competitiveness is one of the potential flashpoints in the run-up to the Bali climate conference. The concern is that strong national measures to reduce greenhouse gas emissions will leave domestic producers at a disadvantage relative to those in countries that do not take similar actions.

Competitiveness concerns are traditionally overblown, although they may be more salient in the face of a truly ambitious post-2012 climate regime (see page 14). Competitiveness is not a concern for all producers, but only for those that are energy-intensive, producing goods that are heavily traded, and based in countries where the energy supply has relatively high greenhouse gas (GHG) emissions. Moreover, there are many positive ways to address competitiveness concerns, international agreement on action probably being the most desirable.

But when international agreement fails, past experience suggests that one fallback is likely to be particularly appealing: some sort of border charge (e.g., a border tax adjustment or BTA) to `level the playing field' between domestic and foreign producers.

The point of such measures would be two-fold. First, they would encourage all countries to strengthen their efforts to address the global challenge. This, for example, is one of the motivations for the Montreal Protocol's ban on imports of ozone-depleting substances from non-Parties to the Treaty - a trade measure of a different sort. Second, they would level the playing field between foreign and domestic producers, ensuring that the former do not gain market share by dint of their domestic regulatory regime. Ultimately, the point is to make the imposing country better able to pursue its clean development path, a course of action that is much tougher when it entails injury to domestic producers.

Border charges to address environmental issues have been proposed by a number of countries, most recently by several EU politicians and institutions, and in two climate change proposals currently before the US Congress. They respond in part to the increased stringency of proposed future action, and in part to the sheer volume of global emissions that are outside of the current Kyoto Protocol targets (around 70 percent). Three questions that should be asked with respect to such measures are:

Are they WTO-legal?

Would they be feasible to administer?

Would they be productive in the wider efforts to `export' the EU's clean development model?

FULL REPORT here




Climatologist says global warming not alarming, carbon fuels not to blame

The Earth is getting warmer, but Alaba-ma's state climatologist says carbon fuels aren't to blame. John Christy, who heads the Earth Sys-tem Science Center at the University of Alabama- Huntsville, told a group of civic and business leaders Tuesday that the Earth's warming is well within historical ranges. He spoke at the Energy and Environ-ment Lecture sponsored by Auburn Mont-gomery and Alabama Power Co.

Carbon dioxide levels have increased 38 percent in the last 100 years, Christy said, leading to an increase in the average surface temperature of about 1.26 de-grees. Even if carbon dioxide doubled, temperatures would increase only about 3.6 degrees, according to Christy. "The climate is always in change," he said. "Glaciers are always advancing or re-treating. "Think of it this way, would you rather the glaciers be advancing?"

Energy use, specifically carbon-based fuels such as coal, is responsible for some temperature increases, Christy said. But the societal benefits of energy far out-weigh the pollution, he added. Life expectancy has soared over the last 100 years, he said, largely because of more efficient energy uses. That makes so-lutions that call for an end to carbon-based fuels unrealistic. "There is no substitute for the carbon fuels we have now," said Christy. Wind and solar power work on a limited scale, he said, but they impact the environment as well.

Christy said those who claim global warming spells doom for society fall into three categories. True believers, he said, claim that any impact humans have on Earth is negative. Others are looking to make a profit. The third group just has a bleak feeling about the environment and wants to do some-thing. The last group can be a positive force, he said, if they make changes based on what he called sound science.

"Everyone should look at their energy uses and find ways to save money," he said. "If you are saving money, you are probably saving energy." The government can help by encourag-ing new fuels. "Making energy more expensive is a regressive tax," he said.

Source

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