AMO & PDO – RIP. That’s the claim here anyway. Might be news to NASA and others.

Recently, meteorologists report that the Atlantic Multidecadal Oscillation (AMO) and the Pacific Decadal Oscillation (PDO) do not appear to exist, says Tech Explorist.

The discovery could have implications for both the validity of previous studies attributing past trends to these hypothetical natural oscillations and for the prospects of decade-scale climate predictability.

The discovery is based on observational data and climate model simulations, that shows there was no reliable proof for decadal or longer-term internal oscillatory signals that could be separated from climatic noise— arbitrary year to year variation.

The apparent main swaying is the well-known El Niño/Southern Oscillation (ENSO).

Scientists noted, “A distinct — 40 to 50-year timescale — a spectral peak that appears in global surface temperature observations appears to reflect the response of the climate system to a combination of anthropogenic and natural forcing rather than any intrinsic internal oscillation.”

. . .

Michael E. Mann, distinguished professor of atmospheric science at Penn State, said, “Given the current sophistication of climate models as seen in their ability to capture the El Niño/Southern Oscillation, we would expect to see consistent evidence for oscillations across a suite of climate models. We found no such evidence.”

Full article here.

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Nature Communications: Absence of internal multidecadal and interdecadal oscillations in climate model simulations (Jan. 2020) – open access

[Authors: Michael E. Mann, Byron A. Steinman & Sonya K. Miller]

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(some ritual ‘greenhouse’ propaganda near the end)