Guest Blog by John McLean

Hardly a day goes by without a new claim about a human influence on climate.  In the last 18 months we’ve been told, not once but three times, that the air circulation across the tropical Pacific is slowing down and it’s all our fault.

The problem is that the scientific papers making those claims have somehow managed to completely ignore the Great Pacific Climate Shift of 1976 despite this being well-known to climatologists.  The changes caused by that climate shift can account for the altered circulation pattern.  Despite what the three papers say we don’t need to include any human influence.

Was the omission of the Climate Shift deliberate or accidental through ignorance?  Neither is particularly palatable in such a controversial field where we expect, but don’t always get, impartial and accurate science.

Of course such an omission in peer-reviewed papers doesn’t reflect well on the reviewers and journals in question, but many of us are used to that bias by now.

See the full analysis here.

In full support of John’s thesis is the above plot of Mantua’s PDO since 1950 with a predominance of the cold phase (La Nina (blue spikes)) until 1976 and then the warm phase (El Nino (red spikes)) after