Can we Trust the Temperature Data?
How a 30-year cooling period was wiped from the record
‘At weather stations in the far north, temperatures have been dropping for 30 years’ Leonard Nimoy, 1979
At a Glance:
A period of cooling between the 1940’s and 1970’s has been wiped from the record!
We can see the missing 30+ year cold snap by looking at the following pieces of evidence:
The cooling-trend that caused climatologists of the 60’s and 70’s to send out grave warnings of an impending Ice Age.
Recent sophisticated temperature reconstructions that show rapid cooling in the mid-19th Century.
A comparison of NASA publications 20 years apart that shows how the mid 19th Century cooling period has been reduced to a mere ‘blip’ in the record.
1. The Ice Age that Never Was!
About half a century ago there was a climate crisis of a very different nature to the one we hear about today.
Warnings of an impending ice age were widespread back in the 1970’s; I even remember it being talked about in the playground of the small Welsh primary school I was attending in the mid 1980’s.
Why were meteorologists making such predictions?
The preceding decades experienced falling global temperatures,
a string of extreme weather events had been experienced, and
crop-growing seasons were getting dangerously short.
Even celebrities were involved in sending out the Ice Age message. An example can be seen below of Leonard Nimoy (aka Dr Spok from Star Trek!) warning of the climate catastrophe that lay ahead.
Among other warnings, in his broadcast, ‘Dr Spok’ mentions:
‘..at weather stations in the far north, temperatures have been dropping for 30 years’
‘..sea coasts, long-free of summer ice are now blocked year-round’
But what happened?
In the period of the 1940’s through to the 1970’s, a cooling trend was widely reported. Here is a list of publications from the 1970’s discussing the prospect of an impending ice age.
You might think that the world, quite simply, started to warm up, and so the warnings of an impending big-freeze melted away along with the polar ice caps!
But there is more to it than that.
The cooling trend upon which claims of an impending Ice Age were based is missing from the modern-day official records! Where did it go?
The figure above shows the modern-day global temperature record from some of our most renowned climate institutes. At best, one could pick out a very modest cooling (shaded in blue), similar in magnitude to the slight cooling trend of the late 19th early 20th century (which didn’t trigger warnings of an impending climate crisis!).
And on closer inspection, the official record shows warming from at least the mid-60’s, possibly earlier. Is Dr Spok likely to have made his 1979 ice age warning had the Earth in fact been warming in the decade and a half leading up to it, as the current record suggests?
2. Temperature Reconstructions
A recent paper by Nikolov and Zeller presents some very interesting temperature reconstructions based on solar energy data. Using a new modelling technique, the authors calculated historical global temperatures based on the amount of sunlight that reached the Earth’s surface over the last 60 years.
This sunlight-derived temperature data, called ‘SSR-based temperatures’ (where ‘SSR’ stands for ‘Surface Solar Radiation’) agrees remarkably well with the official global temperature records over the last 40 years.
However, prior to the mid-1980’s, the SSR-based temperature deviates significantly from the official global temperature record.
While it is difficult to look at anything other than broad trends in graphs with different scales on their axis, I’ve done a rough comparison of;
the 1960-70 temperature trend from data published by the National Centre for Atmospheric Research from 1975, and
the recent, SSR-based and official temperature data over the same period.
There is a reasonable match between the official data published in the 1970’s (seen on the left in the image below), and the recent solar based reconstruction (shown on the right). Both are in stark contrast to the current official records (also shown on the right).
3. NASA’s Modified Data
Here is my third and final ‘smoking gun’, and it involves one of the most famous institutions on the planet;
NASA.
Below are two graphs taken from NASA publications of equivalent global temperature data; the first from a 1999 NASA publication and the second from 2022, accessed recently from the NASA website. I’ve shaded the time-period in question in blue.
If you look closely the new records suggest that global temperatures basically remained flat during this period.
In the 1999 NASA data, there is a definite cooling trend during this period (the same period that led to the warnings of the ice age discussed above).
Looking more closely at NASA’s current data, you can see that the entire cooling period in the middle of the last century has been reduced to a small bump.
It would be quite easy to smooth it out entirely (as indicated by the orange dashed line in the figure below), leaving a record that shows temperatures having risen consistently for the last 120 years.
Conclusion
Scientific records and media publications of the past showed a clear cooling period in the middle of the 20th century. This cooling period is absent from most current records of global temperature.
It is well-known that climatologists make retrospective adjustments to historical data sets. Reasons such as evolving measurement technologies, updated protocols and accounting for changes in land-use are given as justification. You can read about them in more detail here should you so wish.
‘‘Independent analyses conclude the impact of station temperature data adjustments is not very large’’ NASA, ‘The Raw Truth on Global Temperature Records’
NASA claims that the impact of such adjustments are ‘not very large’.
But from what I can see an entire 30+ year cooling period, which caused widespread crop shortages and led to a decade of dire warnings of an impending climate catastrophe, has simply been wiped from the record!
And in doing so, it allows claims of a consistently warming planet over the last 100 years to go unchallenged. Few would take the time to see that the (original) data would suggest otherwise.
We took many technological leaps during the 1940’s-1970’s such as flying across the Atlantic at the speed of sound and inventing the cell phone. In the ultimate giant leap for mankind we even put a man on the moon (!).
But measuring global temperature trends back here on Earth was, apparently, a step too far!
I hope you enjoyed!
-T