From THE DAILY SCEPTIC

by Chris Morrison

A sensational science paper has blown holes in alarmist claims that global temperatures are surging. Just published results in Nature show “limited evidence” for a warming surge. “In most surface temperature time series, no change in the warming rate beyond the 1970s is detected despite the breaking record temperatures observed in 2023,” the paper says. Written by an international group of mathematicians and scientists, it is unlikely to be acknowledged in the mainstream media where general hysteria reigns over the anomalous 2023 experience. As we have seen, constant misinformation is published to scare the general public and this is exemplified by climate comedy-turn Jim ‘jail the deniers’ Dale forecasting almost daily Armageddon and exhorting people to “join up the dots”.

In science, one swallow does not make a summer and in climate science it is impossible to show a trend by picking on short periods or individual weather events. This paper is an excellent piece of climate science work since it takes the long statistical view and challenges the two-a penny clickbait alarmists looking for a headline on the BBC. The Intergovernmental Panel on Climate Change is a biased body but it understands the importance of long-term climate trends by stating, much to the chagrin of Net Zero-promoting activists, that it can find little or no human involvement in most extreme weather events either in the past or in the likely immediate future. But these findings, along with the paper on the warming trend, are inconvenient to those promoting the unproven claim that humans control the climate thermostat by utilising hydrocarbons.

The paper is highly technical and mathematically-inclined readers can study the full workings out in the open access publication. It notes that global temperature datasets fluctuate due to short-term variability and this often creates the appearance of surges and slowdowns in warming. It is important to consider random noise caused by natural variation when investigating the recent pauses in temperature and the more recent “alleged warming acceleration”, it adds. In fact there have been a number of plausible explanations given for the recent spike, with attention focused on the massive Hunga Tonga submarine volcano adding 13% extra water vapour to the stratosphere, a strong El Niño and even the reduction in atmospheric particulates caused by recent changes in shipping vessel fuel. Several “changepoints” were used by the mathematicians and it was found that “a warming surge could not be reliably detected any time after 1970”.

While the focus was on whether there had been a continued acceleration in the rate of global warming, it was recognised how unusual the surface temperature anomalies were in 2023. Indeed they were, and it was widely argued that this showed the climate was breaking down, or in the silly words of the UN chief Antonio Guterres that the planet was “boiling”. Last year’s hysterics were useful for short-term alarmism but they help destroy the ‘settled’ science around CO₂. If human-caused CO₂ is responsible for the rise, why did the temperature pause from 1998-2012 when atmospheric levels of the gas were on the up. Does alarmism on the BBC and most other mainstream media only apply when the temperatures spikes upwards for a few months?

One of the key conclusions in the paper arises from considering two time series – 1970-2023 and 2013-2023. This of course includes the early 1970s when global cooling fears were all the rage and average temperatures were falling. Estimated temperature trends were said to be 0.019°C per year for the first time segment and 0.029°C for the second that includes the spike from last year. This 0.029°C estimated slope “falls far short” of an increase needed to point to a change in the warming trend in the recent past. This is because of short-term variability in the U.K. Met Office HadCRUT global database since 1970 and “uncertainty” of the 2012 changepoint. This uncertainty arises over speculation as to whether 2012 and the ending of the pause was a year marking an important change in the longer time series. ”The HadCRUT record is simply not long enough for the surge to be statistically detectable at this time,” they note.

Cliff Mass is the Professor of Atmospheric Science at the University of Washington. He has a golden rule of weather extremes: “The more extreme a climate or weather record is, the greater the contribution of natural variability, and the smaller the contribution of human-caused global warming.”

The mathematicians used changepoint statistical techniques which were designed to identify structural changes over time. Four global mean surface temperature records over 1850-2023 were used including HadCRUT. This of course is problematic since there is substantial evidence that these datasets hype the warming trend by their careless treatment of urban heat corruptions – the fact that urban areas become warmer through ongoing development. In addition, substantial retrospective adjustments are made, often cooling the past and warming the near present to increase the ‘trend’. Despite writing copiously about the 1998-2012 ‘pause’, the Met Office has now removed it from its own record by adding 30% retrospective warming. Perhaps the Met Office need not have worried, with the mathematicians noting that the pause was “not unusual” given the level of short-term variability present in the data. But these datasets are the best we have and nobody doubts that the planet has warmed a small amount over the last 200 years since the lifting of the little ice age. For want of anything better, using these datasets for scientific analysis is fair, although it could be suggested that overall warming is probably less than suggested by this paper.

Chris Morrison is the Daily Sceptic’s Environment Editor.