Explosive Volcanism Triggered the Little Ice Age

Headline at Ice Age Now blog:

Volcanism alone can explain the Little Ice Age (LIA), researchers insist. Low sunspot activity is not the culprit.

Precisely dated records of ice-cap growth from Arctic Canada and Iceland show that “Little Ice Age summer cold and ice growth began abruptly between 1275 and 1300 AD, followed by a substantial intensification 1430–1455 AD,” researchers found.These intervals of sudden ice growth coincide with two of the most volcanically perturbed half-centuries of the past millennium, the study shows. “Explosive volcanism produces abrupt summer cooling at these times.”“Our results suggest that the onset of the LIA can be linked to an unusual 50-year-long episode with four large sulfur-rich explosive eruptions, each with global sulfate loading >60 Tg.

”Once the ice age was triggered, cold summers were maintained by sea-ice/ocean feedbacks long after volcanic aerosols were removed. the authors assert. “Large changes in solar irradiance are not required.

Full Post is HERE.
The original research document is HERE.

“Abrupt onset of the Little Ice Age triggered by volcanism and sustained by sea-ice/ocean feedbacks,” published on 31 January 2012

From a comment on the Ice Age Now Post:

From what I see on this page it sounds like the researchers are not aware of what causes the increased volcanic activity and earthquakes in the first place. Namely a very weak solar cycle is directly linked to a substantial increase in volcanic activity. The “experts” are still having a hard time connecting the dots.

I have published the graphic below several times showing an increase in volcanic activity during grand minimums. The question is still open, how does a quiet sun cause an increase in volcanic activity on the earth?

GTEMPS

Your thoughts are most welcome?  What is the solar connection to earthquakes on the planet? It looks like the sudden cool down starts before the plethora of volcanic eruptions on the chart. Does the cooling cause eruptions?

 

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Solar minimums may be final piece of puzzle in fall of Western Civilisation

Sam Khoury writing in the Nation

[ooo]

By the 1st century BC, Rome was the most advanced and powerful civilisation on Earth and Romans’ material wealth was skyrocketing. Men and women are increasingly less interested in marriage and no-fault divorce is enacted. Birth rates start to decline below the replacement rate. The citizen soldiers are eventually replaced with professional soldiers who expect compensation and are loyal to the military itself, not the state. As the empire expands in a series of wars of choice it is becomes increasingly multicultural thanks to new citizens from conquered territories. Their loyalty is in question but Rome depends on them as mercenaries to defend the declining state. The government and the military industrial complex replace the private sector as the sole entity responsible for everyone’s well-being. There is moral decay and brutality as Julius Caesar brags about killing one million Gauls. This period could be compared our own world since 1970. By the 400s Rome is being pillaged by Visigoths and Vandals, who ensure it never makes it to the 500s.

However there was something else occurring in the 400s that wasn’t happening in the preceding centuries. Although corruption and immorality were rife, the scientific and historical record shows the climate cooled but, more destructively, it became erratic. Long dry conditions were interrupted by intense deluges. Unseasonal spells of cold weather became the norm. Although solar activity records only date back to the 1600s, these conditions were almost certainly the result of a combination of low solar activity and high volcanic activity – much like the post-medieval warm period that saw solar minimums like the so-called Maunder and Dalton and large volcanic eruptions like the Tambora which, combined with the Dalton, created freezing summers. The result during the 400s was rising food prices, which along with the other factors created deep social dissatisfaction as the economy faltered.

There are proposals on the table to turn the Afghani war over to mercenaries and bring out troops home to a land were middle-class citizens are questioning the role of government and wealth disparity created by robotic and AI technology is growing.  We are becoming more like the Roman Empire, dropping birth rates, fewer marriages, and more debauchery.  Moral decay and fear of the government rampant.  But a significant change in the climate, a highly erratic climate of droughts and floods destroyed the food supply and that was the final blow to the Roman Empire.  Is this or fate?

Enter the monkey in the wrench. After 200 years of healthy solar maximums, solar activity has been plummeting since 2010 and the first solar minimum will hit bottom around 2021. By the 2030s solar physicists now reckon that a grand solar minimum will consume most of the rest of the century. Volcanic activity has also been on the increase and more is expected as eruptions occur most often during solar cycle peaks or at solar minimums. In previous articles published in this newspaper I chronicled increasingly intense and erratic weather patterns that have coincided with the lower solar activity since 2010. The latest include a cold front that descended on the US Midwest in late June dropping temperatures to near freezing, and recent snowfall 200 kilometres south of Moscow in Tarttarastran. Wheat futures immediately rose 6 per cent. At this time the world takes cheap foodstuffs for granted. A change of this reality in the future could shake the global world order to its foundations.

Full Article in HERE.

 

New Study By German Physicists Concludes We Can Expect Climate Cooling For Next 50 Years!

By P Gosselin at the No Tricks Zone

German physicists: “CO2 plays only minor role for global climate”

In a just published study in The Open Atmospheric Science Journal here, German scientists Horst-Joachim Lüdecke and Carl-Otto Weiss have used a large number of temperature proxies worldwide to construct a global temperature mean over the last 2000 years, dubbed G7, in order to find out more about the sun’s role on climate change.

Their results drop a huge surprise on the laps of scientists who have long believed the earth is warming due to human-emitted CO2.

The analysis by the German scientists shows the strongest climate cycle components as 1000, 460, and 190-year periods. The G7 global temperature extrema coincide with the Roman, Medieval, and present optima, as well as the well-known minimum of AD 1450 during the Little Ice Age.

Correlation 0.84

Using further complex analyses, they constructed a representation of G7, which shows a remarkable Pearson correlation of 0.84 with the 31-year running average of G7.

The authors used extensive local temperature proxy data [2 – 6] together with Britain’s Hadley CRU temperature records since 1870 and the recent satellite measurements, and combined them to make up the global temperature time series G7 for the last 2000 years.

Luedecke_1
In accordance to the definition of climate, the blue curve in the paper’s Fig. 3, shown above, depicts the climate history as the 30-year running average of the grey curve. Noteworthy, the historically known temperature extrema are well reproduced by the blue climate curve: The Roman Optimum (~0 AD), the Medieval Optimum (~1000 AD), the Present Optimum, as well as the Little Ice Age (~1500 AD),

Also the pronounced minimum of 1450 AD, when the vines in southern France were killed by cold. Also clearly shown by the climate curve is the warming from 1850 to 1995.

The detailed analysis of the local records show in general a multitude of peaks, the authors say, and the G7 however shows only 3 dominant peaks, which correspond to cycles known from local studies, of approx. 1000, 500, 200-year periods. The combination of local records to a global record apparently averages out local cycles and emphasizes global cycles.

The sum of these three dominant cycles (red curve in Fig. 3) reproduces the measured climate (blue curve in Fig. 3) with a remarkable correlation of 0.84.

In particular the sum of the three cycles shows the temperature increase from 1850 to 1995 as a result of the three natural cycles, the German researchers say, adding: “Thus one can conclude that CO2 plays only a minor role (if any) for the global climate.”

Lüdecke and Weiss note that the present maximum of the cycle sum corresponds well with the world temperature stagnation since 1995 AD, the stagnation unexplained by current climate models. As the dominant cycles have persisted for an extended time, one can assume that they will persist for the near future. They write: “This allows to predict cooling until 2070 AD.”

References are HERE.