The claimed warming rate during the (1998-2001 to 2012-’13) “hiatus” ranged from -0.07°C to +0.17°C per decade.
In late 2012, the IPCC had an ongoing dilemma about what to do about the uncooperative global temperatures. The HadCRUT3 data set government bureaucrats had been using since the first report in 1990 actually showed the global mean surface temperatures had been declining since 1998. This was not going further the we-must-act-on-global-warming-now narrative, of course.
Enter Phil Jones, the global temperature data set overseer at East Anglia’s Climate Research Unit (CRUTEM). He’s the scientist who famously admitted that when the temperature data doesn’t exist, they are “mostly made up.”
Image Source: FOIA, e-mail #2729
Jones’s CRU and the Met Office (Hadley) then jointly constructed the newer HadCRUT4 version to help advance the narrative. This version changed the data just in time for the 5th IPCC assessment (AR5, 2013). The 1998-2001 temperatures were allowed to stay the same, but an additional 0.1 to 0.2°C was tacked on to anomalies from 2002 onwards. The effect was to transform the 1998-2012 slight cooling in HadCRUT3 into a 0.04°C per decade−1 warming in HadCRUT4.
Image Source: woodfortrees.org
When the IPCC report was published months later, they admitted 111 of 114 CMIP5 modeling attempts wrongly simulated the previous 15 years of global temperature progression. That’s a 97% failure rate. But instead of embarrassingly reporting on 15 years of net cooling, the 2013 IPCC report characterized the new fangled 0.04°C per decade−1 warming trend as a global warming hiatus instead.
Image Source: IPCC AR5 (Chapter 9), 2013
A new study (Wei et al., 2022) commemorates the 1998-2001 to 2012-’13 “global warming slowdown” that used to be a hiatus…that used to be a cooling.
The authors reference 90 peer-reviewed scientific papers published from 2009 to 2019. Over half of these global warming pause or hiatus papers were published from 2013 to 2015.
“The warming rates greatly vary between −0.07° and 0.17°C decade−1, representing weak cooling and strong warming, respectively. This may directly induce controversies over the authenticity of the slowdown.”
Instead of settling on the already up-adjusted 0.04°C per decade−1 warming trend reported in 2013, the adjustments to the past temperature trends now double this to a 0.08°C per decade−1 warming rate (39 papers) during the “slowdown” that used to be a hiatus…that used to be a cooling.
Image Source: Wei et al., 2022
HadCRUT4 temperature data now shows 8 straight years of cooling (2014 to 2022).
“… the decadal-scale warming slowdown is not incompatible with the centennial-scale anthropogenic warming trend. In the long run, the global temperature has undoubtedly been warming over the whole instrumental period, responding to the continuously increasing greenhouse gas concentrations in the atmosphere …” (Wei et al).
That statement is a non sequitur, ‘not incompatible’ simply does not rule out anthropogenic warming, it does not necessarily rule it in as a factor let alone the only factor.
The conclusion similarly ‘suffers from period selection bias’ as it would be a remarkable coincidence that anthropogenic warming as the sole forcing factor started at the same time as the instrumental record.
The global climate has been warming and cooling perpetually, any fluctuation is ‘not incompatible’ with any combination of climate factors.
Besides concerning attribution the IPCC only goes so far to claim: ‘most of the global average warming over the past 50 years is very likely due to human activities’ (2007).
There has been 3 global warming events during the satellite era. The last warming event started the end of 2015 and last 6 months. The previous global warming event started the end of 1997 and lasted 6 months. The first warming events was at the end of 1983 but this warming event is harder to identify because of the El Chichon volcano which had a short term cooling effect over 1983. There is a temperature hiatus after each warming event.
These warming events were all caused by el ninos.
It is driven by sunlight (short wave radiation) and natural changes in cloud cover change the amount of short wave radiation warming the planet.
CO2 has little to do with it as it forcing is too small.
The planet is in a temperature hiatus now. The planet will not warm again unless there is another strong el nino.
None of the IPCC global temperature models show this warming pattern of warming events, followed by a temperature hiatus even though they are hind cast models.
[…] New Study: 90 Papers Were Published On The ‘Hiatus’ From 2009-2019. Now They Say It Neve… […]
More data diddling as usual
It speaks poorly of the quality of opposition to the CAGWH that skeptics’ seeming lack of interdisciplinary tolerance and curiosity precludes recognizing that a Pauli-like rejection of basic consensus physics as “not even wrong” could undercut and stop what long ago became obsessive, profitless trifling. We must open our own minds.
[…] Read the Full Article […]
Of course it never happened. Job security trumps truth every time.
[…] graph above, published in the climate science website No Tricks Zone, shows the change from HadCRUT3 to HadCRUT4. […]
[…] Quelle: The Daily Sceptic/ No Tricks Zone […]
Please let’s be accurate. Jones saying that the SST normals “are made up” is a short-form way of saying that they are modelled. Read the main paper for HadSST3 (for sure), and probably in the paper for HadSST4, and you’ll find that normals (i.e. 1961-1990 averages) for each grid cell are estimated via that model that’s based on incoming radiation and these estimates are replaced with data from observations if it’s available.
Yes, there are (huge) problems with temperature adjustments, which are ultimately only estimates of what would have been measured if the data was recorded with the current instruments and screening at the current location.
Yes, the trend since April 2014 is flat (and trends from a few months later are definitely downward).
But let’s not get hung up on the “temperatures are made up” issue when the story is rather different.
For the SH south of 45S, the data are not available. They even admit this in papers.
“Even in recent decades, the Southern Ocean south of 45S is largely missing.”
The “data” that were available are from canvas buckets (almost exclusively in the NH) that are subject to seven grossly disqualifying errors. Bucket “data” are worthless. And this (SSTs) is 71% of the globe – 40% of the globe in the SH, where we effectively have no reliable data until ARGO.
I have no problem remaining “hung up” on changing data to fit climate narratives.
The RSS and UAH data were 99.95% aligned for many years – only separated by 6 one-thousandths of a degree over per decade as of March, 2015. Then Carl Mears decided he no longer wanted Chris Monckton to use his data to produce 18-year “pause” charts and the trend went from 0.12C per decade to 0.2C per decade overnight (2017). Making up data happens, John.