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Javier's comment
#1
From HERE


Quote:“El Nino is a naturally occurring phenomenon, … that occurs in a two- to seven-year cycle.”

Why is it called a cycle? It is not even a periodic oscillation. Just an oscillation with an average and standard deviation occurrence. A frequency analysis of El Niño would yield nothing at all.

What most people ignore, however is that El Niño is a phenomenon that didn’t occur during the early Holocene before 7000 years ago, and that it has a relation with Bond events. It is a feature of a cooling world.

[Image: ENSO-Bond_zpsqiqwmj1z.png]
It is our attitude toward free thought and free expression that will determine our fate. There must be no limit on the range of temperate discussion, no limits on thought. No subject must be taboo. No censor must preside at our assemblies.

–William O. Douglas, U.S. Supreme Court Justice, 1952
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#2
More from Javier, about the chart, in the first post,from HERE


Quote:I believe I can. Most of the paleo evidence shows that El Niño increased at the end of the Holocene Climatic Optimum and has been on the rise during the Neoglacial Period until around 1200 years ago. It is now less strong and frequent.

“ENSO variability was present throughout the Holocene but underwent a steady increase from the mid-Holocene to the present. In the mid-Holocene, extreme warm El Niño events were smaller in amplitude and occurred less frequently … as in the present climate.”

Clement, Amy C., Richard Seager, and Mark A. Cane. “Suppression of El Niño during the Mid‐Holocene by changes in the Earth’s orbit.” Paleoceanography 15.6 (2000): 731-737.

“The onset of modern ENSO periodicities is identified by palaeo-ENSO records throughout the tropical Pacific region ~ 5000 years ago, with an abrupt increase in ENSO magnitude ~ 3000 years ago. Individual ENSO events recorded by corals reveal that the precipitation response to El Niño temperature anomalies was subdued in the mid-Holocene. The apparent non-linear onset of ENSO in the late Holocene appears to reflect abruptly enhanced interaction between the Southern Oscillation and the Pacific Intertropical Convergence Zone.”

Gagan, Michael K., et al. “Post-glacial evolution of the Indo-Pacific warm pool and El Nino-Southern Oscillation.” Quaternary International 118 (2004): 127-143.

“From about 15,000 to about 7000 calendar years before the present, the periodicity of clastic deposition is greater than or equal to 15 years; thereafter, there is a progressive increase in frequency to periodicities of 2 to 8.5 years. This is the modern El Niño periodicity, which was established about 5000 calendar years before the present.”
Rodbell, Donald T., et al. “An ~ 15,000-year record of El Niño-driven alluviation in southwestern Ecuador.” Science 283.5401 (1999): 516-520.

“We find that changes on a timescale of 2–8 years, which we attribute to warm ENSO events, become more frequent over the Holocene until about 1,200 years ago, and then decline towards the present.”
Moy, Christopher M., et al. “Variability of El Niño/Southern Oscillation activity at millennial timescales during the Holocene epoch.” Nature 420.6912 (2002): 162-165.

“Paleoclimate records from the tropical Pacific suggest the early to mid-Holocene was a period of reduced El Niño/Southern Oscillation (ENSO) variability, with a transition to modern, increased ENSO frequency occurring some time in the last few thousand years… Maximum Holocene precipitation and inferred ENSO variability occurred between 2000±100 and 1500±70 cal years BP, during the same period that six other independent proxy records suggest higher ENSO frequency and longer, stronger El Niño events.”

Conroy, Jessica L., et al. “Holocene changes in eastern tropical Pacific climate inferred from a Galápagos lake sediment record.” Quaternary Science Reviews 27.11 (2008): 1166-1180.
I also made this figure with the data from Moy et al.
It is our attitude toward free thought and free expression that will determine our fate. There must be no limit on the range of temperate discussion, no limits on thought. No subject must be taboo. No censor must preside at our assemblies.

–William O. Douglas, U.S. Supreme Court Justice, 1952
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