“But we know that Linah Ababneh updated the Sheep Mountain data in 2002. We also know that Linah Ababneh’s update, aside from finding a difference between strip bark and whole bark chronologies, did not replicate Graybill’s results and had no HS shape whatever. (Figures for Sheep Mountain for strip bark and whole bark from 1600 on are shown separately in the thesis.) So the Sheep Mountain chronology had been updated – why wouldn’t this update have been used, aside from it not having a HS shape?”
Ababneh Fig. 5. Cold and warm periods as inferred from tree ring widths chronology (Ababneh, 2006, This study) fluctuations above and below the mean after normalizing, whole-bark and strip-bark chronologies are grouped together from two sites Patriarch Grove and Sheep Mountain.
From Climate Audit: ‘Hughes and the Ababneh Thesis’
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Researchers at the Institute of Occult Time Travel have discovered that the world’s recovery from the latest Ice Age was the domestication in North America of Wooly Mammoths. Their belches and farts, coupled with annual burning of the Great Plains, released enough CO2 to rescue the Earth (or at least, its scorned human denizens) from becoming an iceball planet.
There are, of course, “deniers” of this theory, who say that there wasn’t an Ice Age, or even a Medieval Warming due to the North American Mammoth-based economy.
Yes Schiller pretty close actually:
http://courses.eas.ualberta.ca/eas457/Ruddiman2003.pdf
The anthropogenic era is generally thought to have begun 150 to 200 years ago, when
the industrial revolution began producing CO2 and CH4 at rates sufficient to alter their compositions
in the atmosphere. A different hypothesis is posed here: anthropogenic emissions of these gases
first altered atmospheric concentrations thousands of years ago. This hypothesis is based on three
arguments. (1) Cyclic variations in CO2 and CH4 driven by Earth-orbital changes during the last
350,000 years predict decreases throughout the Holocene, but the CO2 trend began an anomalous
increase 8000 years ago, and the CH4 trend did so 5000 years ago. (2) Published explanations for
these mid- to late-Holocene gas increases based on natural forcing can be rejected based on paleoclimatic
evidence. (3) A wide array of archeological, cultural, historical and geologic evidence points
to viable explanations tied to anthropogenic changes resulting from early agriculture in Eurasia,
including the start of forest clearance by 8000 years ago and of rice irrigation by 5000 years ago. In
recent millennia, the estimated warming caused by these early gas emissions reached a global-mean
value of ∼0.8 ◦C and roughly 2 ◦C at high latitudes, large enough to have stopped a glaciation of
northeastern Canada predicted by two kinds of climatic models. CO2 oscillations of ∼10 ppm in the
last 1000 years are too large to be explained by external (solar-volcanic) forcing, but they can be
explained by outbreaks of bubonic plague that caused historically documented farm abandonment
in western Eurasia. Forest regrowth on abandoned farms sequestered enough carbon to account for
the observed CO2 decreases. Plague-driven CO2 changes were also a significant causal factor in
temperature changes during the Little Ice Age (1300–1900 AD).