A Quick Note from Kip Hansen
A quick note for the amusement of the bored but curious.
While in search of something else, I ran across this enlightening page from the folks at UCAR/NCAR [The University Corporation for Atmospheric Research/The National Center for Atmospheric Research — see pdf here for more information]:
“What is the average global temperature now?”
We are first reminded that “Climate scientists prefer to combine short-term weather records into long-term periods (typically 30 years) when they analyze climate, including global averages.” As we know, these 30-year periods are referred to as “base periods” and different climate groups producing data sets and graphics of Global Average Temperatures often use differing base periods, something that has to be carefully watched for when comparing results between groups.
Then things get more interesting, in that we get an actual number for Global Average Surface Temperature:
“Today’s global temperature is typically measured by how it compares to one of these past long-term periods. For example, the average annual temperature for the globe between 1951 and 1980 was around 57.2 degrees Fahrenheit (14 degrees Celsius). In 2015, the hottest year on record, the temperature was about 1.8 degrees F (1 degree C) warmer than the 1951–1980 base period.”
Quick minds see immediately that 1.8°F warmer than 57.2°F is actually 59°F [or 15° C] which they simply could have said.
UCAR/NCAR goes on to “clarify”:
“Since there is no universally accepted definition for Earth’s average temperature, several different groups around the world use slightly different methods for tracking the global average over time, including:
NASA Goddard Institute for Space Studies
NOAA National Climatic Data Center
UK Met Office Hadley Centre”
We are told, in plain language, that there is no accepted definition for Earth’s average temperature, but assured that it is scientifically tracked by the several groups listed.
It may seem odd to the scientifically-minded that Global Average Temperature is measured and calculated to the claimed precision of hundredths of a degree Celsius without first having an agreed upon definition for what is being measured.
When I went to school, we were taught that all data collection and subsequent calculation requires the prior establishment of [at least] an agreed upon Operational Definition of the variables, terms, objects, conditions, measures, etc. involved.
A brief of the concept: “An operational definition, when applied to data collection, is a clear, concise detailed definition of a measure. The need for operational definitions is fundamental when collecting all types of data. When collecting data, it is essential that everyone in the system has the same understanding and collects data in the same way. Operational definitions should therefore be made before the collection of data begins.”
Nonetheless, after having informed the world that there is no agreed upon definition for Global Average Temperature, UCAR assures us that:
“The important point is that the trends that emerge from year to year and decade to decade are remarkably similar—more so than the averages themselves. This is why global warming is usually described in terms of anomalies (variations above and below the average for a baseline set of years) rather than in absolute temperature.”
In fact, the annual anomalies themselves differ one-from-another by > 0.49°C — an amount just slightly smaller than the whole reported temperature anomaly from 1987 to date (a 30-year climate period). [The difference between GISS June 2017 and UAH June 2017].
So, let’s summarize:
- We are told that 2015, the HOTTEST year ever, was …. what? ….. 59°F or 15° C – which is not hot except maybe in the opinion of the Inuit and other Arctic peoples — which may be a clue as to why they really talk in anomalies instead of absolute temperatures.
- Although a great deal of fuss is being made out of Global Average Temperature, there is no agreed upon definition of what Global Average Temperature actually means or how to calculate it.
- Despite the problems of #2 above, major scientific groups around the country and the world are happily calculating away on the as-yet undefined metric, each in a slightly different way.
- Luckily (literally, apparently) the important point is that although all the groups get different answers to the Global Average Surface Temperature question – we suppose it’s because of that lack of an agreed upon definition of what they are calculating — the trends they find are “remarkably similar”. [That choice of wording does not fill me with confidence in the scientific rigor of the findings — it so sounds like my term – “luckily”]. Even less reassuring is being told that the trends are “more [remarkably similar] … than the averages themselves.”
- And finally, because there is no agreed upon definition of Global Average Temperature and the results for the undefined metric from varying groups are less [remarkably] similar than the trends; even the calculated anomalies themselves from the different groups are as far apart from one another as the entire claimed temperature rise over the last 30 year climatic period.
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Author’s Comment Policy:
Although some of this brief note is intended tongue-in-cheek, I found the UCAR page interesting enough to comment on.
Certainly a far cry from settled science — both parts by the way — not settled — and [some of it] not solid science.
I’m happy to read your comments and reply — but not to Climate Warriors.
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Using anomalies to study temperatures, when we have such a ridiculously small set of numbers for an almost incomprehensible reality, is simply nonsense.
1- There is no such thing as “normal” in climate or weather.
2- What exactly am I supposed to expect in the future based upon the range of possibilities we see in the geologic record? Are the changes we see happening really all that extreme?
3- No.
a·nom·a·ly
əˈnäməlē/
noun
1. something that deviates from what is standard, normal, or expected.
Anomalies only exist in the minds of the creators of “normal”.
There is a way to calculate a meaningful average and this is the Stefan-Boltzmann temperature of an ideal black body emitting the average emissions of the surface and is the convention used for establishing temperatures from satellite measurements whose sensors only measure emissions. Averaging emissions is far more valid then averaging temperature, since Joules are Joules and each is capable of the same amount of work, in fact the units of work are Joules. The system quite linear in Joules which should be expected based on the constraints of COE. The problem is the temperature centric sensitivity used by the consensus is intrinsically nonlinear, where emitted energy is proportional to the temperature raised to the forth power.
The reason they do this is that expressing the sensitivity as 0.8C per W/m^2 sounds plausible, while expressing the same thing in the energy domain becomes 4.3 W/m^2 of incremental surface emissions per W/m^2 of forcing and is obviously impossible. The 1 W/m^2 of forcing must result in 3.3 W/m^2 of ‘feedback’ and any system who’s positive feedback exceeds the input is unconditionally unstable. The climate system is quite stable, otherwise we wouldn’t even be here to discuss it.
Regarding the large difference between the GISS and UAH anomalies for June 2017: These datasets have different baseline periods. GISS uses 1951-1980, and only two of those years are in the US record. I don’t remember UAH’s baseline period, but I doubt it begins before 1985.
And they work out their average, when half of the world has no data!
https://www.ncdc.noaa.gov/temp-and-precip/global-maps/
🙂 This one made me laugh… Its the precision they claim to have that drives me nuts. It’s just not possible given the data, the instruments used over the time period used, and the methods they use to calculate an “average”.
So now I have a new thought to make me chuckle – they don’t even know what it is they are measuring. That actually is not surprising – it explains how they (the activists) can so easily change their story – just go with the data and methods that back your story line instead of committing to a method.
I have a suggestion, why not just use the raw data as is and accept the error margin that goes with it? So you have data starting in the 1800’s with a wide error and better data as you get to present. I bet used in such a way, the entire story of AGW disappears into the margin of error.
https://en.wikipedia.org/wiki/Circular_reasoning
And in spite of calculating an actual number there is never any discussion of error measurement. Anyone that has actually done any sort of statistical analysis knows this is possible to do and it will give remarkably useful information about your average from year to year. Specifically it will tell you whether the variability from year to year is within relative norms expected. We could then actually have a discussion of whether we should be using 1-2-3 standard deviations in the discussion depending on the degree of confidence you wanted in those numbers (99-95-68%). But we don’t do that. Why? Because it would detract from the anxiety.
This mean that 2015 was hottest than every preceding year and warmer of 1 degree C than the 30 years mean? I think that mean must be compare to other mean. Or single warm data with mean of warm data.
Where am I wrong in this?
I keep belabouring this point, so here goes again.
The hottest year ever was 2015 and it was 59F or 15C and yet in 1998 it was and still is clearly stated that the temperature in 1997 was 62.45F or 16.92C and in 1999 they said 1988 was even hotter.
They currently show 1998 as being 58.13F or 14.53C just by changing baseline – Yeah Right!
Anomalies make it easier to hide the cheating……
There is no such thing as an average temperature. You can’t even measure the average temperature in a room (without measuring the temperature of every molecule), let alone a planet’s atmosphere.
I’m reminded of a story about the difference between accuracy and precision.
Seems a recently minted engineer was doing calculations out to several decimal places when his boss looked over his shoulder and observed, “I don’t know about that last number, but the first one is wrong.”
I believe Norman Augustine had a law regarding “On making a precise guess.”
“The weaker the data available upon which to base one’s conclusion, the greater the precision which should be quoted to give the data authenticity.”
IPCC AR5 Annex III: Glossary
Energy budget (of the Earth) The Earth is a physical system with an energy budget that includes all gains of incoming energy and all losses of outgoing energy. The Earth’s energy budget is determined by measur¬ing how much energy comes into the Earth system from the Sun, how much energy is lost to space, and accounting for the remainder on Earth and its atmosphere. Solar radiation is the dominant source of energy into the Earth system. Incoming solar energy may be scattered and reflected by clouds and aerosols or absorbed in the atmosphere. The transmitted radiation is then either absorbed or reflected at the Earth’s surface. The average (WAG) albedo of the Earth is about 0.3, which means that 30% of the incident solar energy is reflected into space, while 70% is absorbed by the Earth. Radiant solar or shortwave energy is transformed into sensible heat, latent energy (involving different water states), potential energy, and kinetic energy before being emitted as infrared radiation.
With the average surface temperature of the Earth of about 15°C (288 K), (SEE THAT??!!)
the main outgoing energy flux is in the infrared part of the spectrum. See also Energy balance, Latent heat flux, Sensible heat flux. (That was back in ‘13 ‘14 when AR5 was being published.)
Global mean surface temperature An estimate of the global mean surface air temperature. However, for changes over time, only anomalies, as departures from a climatology, are used, most commonly based on the area-weighted global average of the sea.
Land surface air temperature The surface air temperature as mea¬sured in well-ventilated screens over land at 1.5 m above the ground.
The SURFACE IS NNNOOOOTTTTT the GROUND!!!!!!!! In fact most weather measuring stations do not even measure or record GROUND temperature.
Now, during the day the earth and air both get hot but objects sitting in the sun get hotter than both. Once the sun goes down the air cools rapidly, the ground does not so the idea that the air warms the ground is patently BOGUS!!!!
The genesis of RGHE theory is the incorrect notion that the atmosphere warms the surface. Explaining the mechanism behind this erroneous notion demands RGHE theory and some truly contorted physics, thermo and heat transfer, energy out of nowhere, cold to hot w/o work, perpetual motion.
Is space cold or hot? There are no molecules in space so our common definitions of hot/cold/heat/energy don’t apply.
The temperatures of objects in space, e.g. the earth, moon, space station, mars, Venus, etc. are determined by the radiation flowing past them. In the case of the earth, the solar irradiance of 1,368 W/m^2 has a Stefan Boltzmann black body equivalent temperature of 394 K. That’s hot. Sort of.
But an object’s albedo reflects away some of that energy and reduces that temperature.
The earth’s albedo reflects away 30% of the sun’s 1,368 W/m^2 energy leaving 70% or 958 W/m^2 to “warm” the earth and at an S-B BB equivalent temperature of 361 K, 33 C cooler than the earth with no atmosphere or albedo.
The earth’s albedo/atmosphere doesn’t keep the earth warm, it keeps the earth cool.
“the average annual temperature for the globe between 1951 and 1980 was around 57.2 degrees Fahrenheit (14 degrees Celsius). In 2015, the hottest year on record, the temperature was about 1.8 degrees F (1 degree C) warmer than the 1951–1980 base period.”
It’s false analysis to compare a 30-year average with the measurement of a single year.
The valid comparison is 1951-1980 with 1996-2015. That difference is about 0.5 C = 0.9 F, half of what NCAR reports.
Nobody is interested in coming up with a standard definition of what constitutes “the globe” that is being averaged because it is the equivalent of setting the goalposts in cement. Remember when the global average temperature wasn’t rising, so they had to add in heat from the deep oceans? A loose definition allows for easy adjustment.
Speaking of operational definitions, how about the term anomaly. Standard dictionary definitions such as the OED on-line definition “Something that deviates from what is standard, normal, or expected” does not seem applicable to annual global mean temperatures. Can someone please explain to me what is the “standard” or “normal” or “expected” annual global mean temperature? The use of the term anomaly in this case seems to continue the recent “trend (sic)” of diluting the specificity of language.
In aviation the standard atmospheric temperature is 15 C. It is now and it was 30 years ago.
I found this blogpost about the difference between average temperature and average irradiance interesting and informative.
http://motls.blogspot.com/2008/05/average-temperature-vs-average.html?m=1
On a side note, check out the equatorial Pacific heat trend. A weak La Nina is forming me thinks.
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/heat-last-year.gif
Seeing as the temperature in 2015 is 1 year/noise, not climate (by their own definition), they should be saying how the period 1986 to 2015 compares to 1951-1980, to be scientific instead of misleading and political!
Using 1951-1980 as the base period is interesting, since temperature was falling and CO2 rising during that period. Why not 1911-1940, which was warmer than 1951-1980 and had a warming rate quite similar to post 1980? Using 1911-1940 would isolate CO2 increase effects (?) from temperature and provide a better baseline for comparison with the current temperature trend. Until 2014, two of our major northern California cities, Santa Rosa and Ukiah, showed cooling compared to the 1930s, and only exhibited warming after “homogenization.” Michael Crichton found the same for Alice Springs, Australia, in his novel “State of Fear,” http://www.thesavvystreet.com/state-of-fear-gets-hotter-with-global-warming/ which I just reads again and find its observations and conclusions as timely as in 2004.
Thank you, Kip, for another thought provoking article.
Re Global Averages, I am curious if anyone has updated that now decades old question: What is the Global Average telephone number?
“When I went to school, we were taught that all data collection and subsequent calculation requires the prior establishment of [at least] an agreed upon Operational Definition of the variables, terms, objects, conditions, measures, etc. involved.”
Yes…that is required for good science, but AGW is not about science. It is about politics and advocacy. In those realms it is a great advantage to NOT have agreed upon operational definitions. It is very important to be able to make things mean anything you want them to mean any time you want. The latest example is the use of the terms alt-right and alt-left. No one can define those terms, but they can be thrown around very effectively in the realms of politics and persuasion.
A good (for the umpteenth time) explanation of the use of anomalies versus absolutes is a recent post at RealClimate: http://www.realclimate.org/index.php/archives/2017/08/observations-reanalyses-and-the-elusive-absolute-global-mean-temperature/