In the much ballyhooed 2008 NOAA “State of the Climate” report on climate change they state, concerning the climate models, something quite relevant to the issues raised by the new story in the UK Daily Mail:
“Near-zero and even negative trends are common for intervals of a decade or less in the simulations, due to the model’s internal climate variability. The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.”
Dr. Roger Pielke Jr. said in 2009:
“Kudos to NOAA for being among the first to explicitly state what sort of observation would be inconsistent with model predictions — 15 years of no warming.”
(h/t to Tom Harris)
Or how about this:
Climategate’s Phil Jones ‘insisted that 15 or 16 years is not a significant period: pauses of such length had always been expected, he said’ in 2012
‘Yet in 2009, when the [temperature] plateau was already becoming apparent and being discussed by scientists, Jones told a colleague in one of the Climategate emails: ‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
‘In other words, though 5 years ago he seemed to be saying that 15 years without warming would make him ‘worried’, that period has now become 20 years’ h/t to Climate Change Dispatch.
Regarding the significance of the period from 1997, recall that Dr. Ben Santer claimed 17 years was the period needed:
They find that tropospheric temperature records must be at least 17 years long to discriminate between internal climate noise and the signal of human-caused changes in the chemical composition of the atmosphere.
MIT Professor Richard Lindzen said something similar in a WUWT guest post:
There has been no warming since 1997 and no
statistically significant warming since 1995.
Yet, today, we see evidence of the goalposts being moved again as the met Office tries to paint this lack of warming “plateau” as being insignificant:
The models exhibit large variations in the rate of warming from year to year and over a decade, owing to climate variations such as ENSO, the Atlantic Multi-Decadal Oscillation and Pacific Decadal Oscillation. So in that sense, such a period is not unexpected. It is not uncommon in the simulations for these periods to last up to 15 years, but longer periods are unlikely.
So we are at 16 years, soon to be 17 years. What happens when we hit 20 years?
Either the models are worth something or they aren’t. In this case it seems they aren’t.
by: Dr. David Whitehouse