Guest Post by Ira Glickstein
Some of the net Global Warming since 1880 is undoubtedly due to human actions, but how much?
[Update 10 April. My PowerPoint Show that includes the following graphic is available for download here: https://sites.google.com/site/iraclass/my-forms/2014%20Global%20Warming%20Civil%20Discourse.ppsx?attredirects=0&d=1 ]
The height of the bars on the graphic indicates the relative magnitude of Natural Processes and Cycles (in BLUE) versus Human-Caused Warming (in RED). The scale on the left is in °C with corresponding °F on the right.
Going from left to right:
The first BLUE bar represents the Atmospheric “Greenhouse” Effect, responsible for about 59°F (33°C) warming. This is the Natural Process that makes life as we know it possible on Earth. The mean temperature on the surface of the Earth is about 59°F (33°C) warmer due to Atmospheric absorption of long-wave radiation by water vapor (H2O), carbon dioxide (CO2), and other so-called “Greenhouse” gases, and the subsequent “back-radiation” of some of this heat energy towards the Earth surface. (See my WUWT Visualizing series [Physical Analogy, Atmospheric Windows, Emission Spectra, and Molecules/Photons
The second bar represents the major Natural “Ice Age” Cycles that have occurred about every 100,000 years according to the ice core records from the past 400,000 years. The climate is always changing, with up and down temperature jigs and jags at all time scales. The major Ice Age Cycles change temperatures over a range of about 13°F (7°C ).
The third bar represents the Human-Caused Warming that my wife and I experienced when we retired from full-time employment and moved from Upstate New York to Central Florida. The average temperature in Florida is about 20°F (11°C ) warmer than that in New York. I miss cross-country skiing a bit, but, overall, we are happy here and we enjoy water aerobics. While not exactly “Global” Warming, this warming was certainly caused by our Human-Caused decision to move and, of course, we enjoy the resulting moderately higher temperatures :^).
The fourth and fifth bars represent the YEARLY 43°F (24°C ) temperature range (July mean minus January mean), and the DAILY 19°F (11°C ) temperature range we experience here in Central Florida. Please notice that these ranges are much larger than the Ice Age Cycles, and they recur on a daily or yearly basis.
The sixth bar represents the mean Global Warming since 1880 based on the official NASA GISS accounting. It is 1.4°F (0.8°C). According to the IPCC, the majority of this Global Warming is due to human activities (mainly unprecedented burning of fossil fuels and land use that has reduced the albedo of the Earth). I have interpreted “majority” to mean about 70% and have therefore allocated 1°F (0.6°C) to Human-Causation and the remaining 0.4°F (0.2°C) to Natural Cycles.
The seventh bar represents my personal opinion as to the actual Global Warming since 1880, discounting the “adjustments” made by the official Climate “Team” that I believe have inflated the temperature record. We know that the US thermometer record is so unreliable that it has had to be “adjusted” several times by the official US Climate “Team” at GISS, see The Past is Not What it Used to Be, and Skeptic Strategy.

The above GISS email from Makiko Sato to James Hansen details seven adjustments to the US thermometer record, made from 1999 to 2007. According to GISS, the very warm year 1998 was originally thought to be 0.541°C (0.97°F) COOLER than 1934, which, in a warming world, would be, let us say Inconvenient. It took multiple “adjustments” to bring them to a dead heat. Further adjustments to the thermometer records subsequent to the 2007 Sato email have brought 1998 up to a significant lead over 1934 :^).
When this email came to light due to a Freedom of Information request, it was explained away by Warmists as follows:
1) The adjustments correct for differing Times of OBServation (TOBS). OK, that could be true, but why did it take so many analyses to come to the correct result? It seems one or two would be sufficient. Also, the 1998 data has been warmed more by the TOBS adjustments than the 1934 data has been cooled. Are we to believe that TOBS was less standardized in 1998 than it was in 1934?
2) The US is only 2% of the Globe. Therefore, any adjustment to US data would have only a minor effect of Global data. True enough, but, if US data is so unreliable that it has had to be adjusted so much, are we to believe that world data is any better? Does anyone really think that years-old data from Asia, Africa, South America is more reliable than US data? That ocean data based on some seaman dropping a bucket overboard, hauling it back, and sticking a thermometer into it, is any better than US thermometer data?
So, unless we believe that the world temperature record is more reliable than the US record, it is likely the world record has also been similarly “adjusted”. Therefore, I have discounted the GISS estimate of Global Warming by about 30%, so actual warming is about 1.0°F (0.6°C). As for allocation of this actual warming to Human- vs Natural-Causes, I believe the IPCC has over-estimated Climate Sensitivity by a factor of two or three, so I have allocated the majority of the warming 0.8°F (0.5°C) to Natural Cycles, and the remaining 0.2°F (0.1°C) to Human-Causation.
I’d appreciate comments on my estimates and conclusions. advTHANKSance
Ira
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.

Here’s a trick question: If you double the temperature at 1C, what do you get?
I like the point you are making, but that’s a pretty confusing graph. A straightforward bar graph, without the pictures, would be easier to follow.
The graphic is too cluttered. The valid points being made in the text are not being reinforced as well as they should be.
It would be nice to see a bargraph of typical daily/yearly variation (range) before warming next to the same thing after warming, it would illustrate that the warming was insignificant compared to daily/yearly fluctuations and that for most of each day/year the temperature after warming was within the normal range that occured before warming.
This is, of course, why the climate deceit community prefer to use a temperature anomaly instead of actual temperatures, because the numbers just aren’t scary at all.
Love the article but have to respectfully disagree – I don’t think we’re causing any warming as they relate it to CO2. I will never be convinced that the heat supposedly coming off our tiny percentage of CO2 can compare to the heat coming from these (all of them, not just this one): https://www.youtube.com/watch?v=CmMSgkSwgQU
The reason the hockey stick graph made such a huge impact was the clarity of the message-whatever we may think of it. The graph you have used is simply too cluttered to follow easily and distracts from your message.
We could do with a roster of talented volunteers at WUWT willing to take information we provide them and turn them into compelling visual images. This would greatly augment the written information we try to put over.
tonyb
Agreed that the visual aids are confusing, to this layman at any rate
Layman thinking oke danger’s global warming. Lets see over 100 years the temperature went up 0,7 degrees Celsius that’s 0,007 degrees per year. Considering the fact that were just leaving an ice age ore maybe are still in one 0,007 degrees per year is nothing let alone danger es. Take In account the upward data fudging and the number will be even lower.
Danger’s global warming is 15 degrees in 10 years then you cane consider it danger’s global warming.
So, unless we believe that the world temperature record is more reliable than the US record, it is likely the world record has also been similarly “adjusted”.
Sea level is also being adjusted.
Finn, if you double 1C you get 2C. If you double 34F you get 68F. If you double 274K you get 548K.
Or if you want double the heat content, as in “what’s twice as hot as 1C”, you need some complicated sums.
Not a very meaningfull question, really.
There is no Greenhouse effect to warm the planet by 33C. This ”need” is produced from the poor energy exchange graphic in AR4/5 which displays a complete misunderstanding of energy exchange. It assumes a flat earth, 24/7 sunshine and in fact the 33C is calculated on the wrong figure. Reality has a rotating planet so a night/day cycle and the sun producing more than enough heat to produce the +14C average.
The theory of the GHE is a political construct not based on empirical data. It violates the laws of thermodynamics so cannot work.
[Sorry, johnmarshall, but the Atmospheric “Greenhouse” Effect is real and 33 °C (59 °F) is a reasonable estimate of how much it raises the average temperature of the Earth Surface. I am not sure that it is exactly 33 °C, since there are some assumptions and simplifications involved in the estimate, but I am certain it is within the range 20 °C to 50 °C. The point I am making in this posting is that even the IPCC’s extreme and high estimate of mostly Human-Caused Global Warming of 0.8 °C (1.4 °F) is only a tiny, tiny fraction of the Global Warming due to Natural Processes and Causes. A short explanation of the Atmospheric “Greenhouse” Effect from Wikipedia http://en.wikipedia.org/wiki/Greenhouse_effect
Ira]
Agree with other posters — graph is too busy.
Was the first graph designed with reader of say “Rolling Stones” in mind ?
The warm atmosphere (of about 59°F/33°C above a planet without atmosphere) that enables a temperate climate in most parts of the World is not only due to so-called greenhouse gases.
According to the Kiehl-Trenberth diagram:
– approx 30% of incoming sunlight is readily reflected back to the outer space (by UV scattering, clouds, atmosphere, and ground surface).
– approx 23% is absorbed by the atmosphere as incoming shortwave UV/Vis electromagnetic radiation (responsible gases are mostly oxygen, nitrogen and water vapour)
– and the rest 47% is absorbed by the ground and re-irradiated back to the atmosphere – and ultimately to the outer space – as long wave IR electromagnetic radiation. Parts of it is absorbed by greenhouse gases (water vapour, CO2, methane, etc.) which is the source of the so-called forcing mechanism.
The controversy about man-made warming (women apparently don’t play a role in it) lies in the CO2 emitted since the beginning of the industrial era which has produced a concentration increase from approx. 280 ppm to 400 ppm today (this is a non-controversial fact).
To know the climate sensitivity to this concentration difference is like to look for the Holy Grail.
see also: https://db.tt/lLY2eW9C
Too iffy. These two premises are reasonable: (1) GISS exaggerates the warming trend; and (2) the IPCC exaggerates climate sensitivity. However, in my opinion there’s too much noise and uncertainty to attempt to quantify the effect of CO2 in the atmosphere if we rely on the surface station data sets, or models that rely upon them. (This follows from a Cartesian principle of inquiry that you should admit when you’re flummoxed and need to give it a rest.) On the bright side, we have enough precise satellite data now to start doing good science.
Also–and maybe it’s just me–but I think there’s some theoretical confusion about the exact mechanism by which CO2 warms the atmosphere. If the mechanism isn’t clearly specified and tested against quality data, it’s bunkum.
People were shorter back in 1934, so when they read the thermometers the parallax would alter the reading, and so we had to adjust the old temperatures to make them correct. Really correct.
Right.
So anyway, since we’re putting things in proper perspective, I’ll dig out my old Galva, Illinois annual average Tmin and Tmax plotted against Dr Mann’s hockey stick. Same scale.
http://www.rockyhigh66.org/stuff/hockey_stick_d_galva.gif
I don’t believe it has been fully established that the CO2 rise is solely from “man-made” sources and not from the ocean releasing CO2 due to the slight increase of temperature in combination with man-released CO2. When the little ice age ended the oceans began warming. This warming would allow it to release a rather large amount of CO2 since its carrying capacity is temperature dependent. I think ONE of the many problems with global warming (climate change, thermogeddon, insert term of the day here) analysis is that the “scientists” have never adequately differentiated these sources. There has been hand waving and dismissal,but never any real analysis or laboratory empirical evidence presented. I guess they can’t figure out how to properly misrepresent the process in a computer model.
[Thanks Owen in GA, I mostly agree! While it is most likely that the majority of the undoubted increase in atmospheric CO2 over the past fifty years is Human-Caused, a substantial portion of the rise in CO2 is due to outgassing from the slight warming of the oceans. The key point here is that the IPCC models assume a value for Climate Sensitivity that is double or triple the actual value, and thus attribute much more temperature raising power to CO2 than is justified. Thus, even if most of the CO2 rise is Human-Caused, only a small fraction (perhaps 1/5th) of the net warming is Human-Caused. Ira]
Here is an excellent review of a new book which covers much of the same ground as this post and also explains why the West has got itself into this situation :
The game is up for climate change believers
Charles Moore reviews The Age of Global Warming by Rupert Darwall
http://www.telegraph.co.uk/culture/books/non_fictionreviews/10748667/The-game-is-up-for-climate-change-believers.html
The review puts a lot of things in perspective and is well worth reading. See also the Readers Comments section below the article. Some are very amusing.
[Can anyone confirm that the latest IPCC hysteria had 4000 contributors but only 60 were scientists?]
The premise is that 5% of human emitted Co2 which is 4/100 of 1 % of atm. gas by weight ’causes’, ‘forces’, ‘impacts’ climate. This concept is counter to the reality that the climate system is not a greenhouse – that is simply warmist propaganda – but a convection system [they used to teach this in grade 9 science]. .05 x .01 is a lot of nothing. Co2 does not ‘force’ a host of many-to-many relationships; nor would it impact local/regional physical thermodynamics. Further there is not a glass ceiling in the troposphere that I am aware of which ‘traps’ said trace chemical.
Humans do impact the environment, but climate is a different and little-understood complexity.
@ur momisugly johnmarshall says: ” … It assumes a flat earth, 24/7 sunshine and in fact the 33C is calculated on the wrong figure. Reality has a rotating planet so a night/day cycle and the sun producing more than enough heat to produce the +14C average….”
I am afraid that this simple fact can not be appreciated by the vast majority of people at the present time. Someday, after the warm-mongering scare is over and the alarmists have moved on to another “the sky is falling” story then perhaps they will be able to see that one must model reality and not fantasy if one wants to understand a thing.
Disclaimer: Those of us who took science in the 60s and 70s still remember a more rational and believable theory of the effects of an atmosphere and that does tend to keep us from joining the present crowd who claims to see the emperors fine garments.
What “human-caused warming”? There very well could be a tiny amount, but if there, it gets lost in the noise of a complex, multi-layered, somewhat chaotic, and not well understood system. For all intents and purposes, even if theory says it should be there, it is non-existant. It is too small to ferret out, and too small to matter in the slightest.
it’s hard enough to keep my house warm with a roof and all the insulation.
what hope an open atmosphere.
steveta, looks like you fell for the trick question.
The language used by climate change believers and alarmists is often filled with deliberately confusing statements and concepts. In order to double a temperature you need to be aware of where your zero is (and I don’t mean the Oval Office). The only zero that makes universal sense is K.
It was 10C today. Tomorrow will be 20C. The temperature will not even remotely double.
Owen in GA says:
I don’t believe it has been fully established that the CO2 rise is solely from “man-made” sources …
In a balance between what was emitted (http://cdiac.ornl.gov/trends/emis/meth_reg.html) since the beginning of the industrial era (1’406 billion m. tons CO2) and what accumulated in the atmosphere (a 400-280=120 ppm rise that corresponds to 960 billion m. tons of CO2), it can be calculated that only 68% of the emitted quantity remained in the air and 32% were captured by oceans, biomass,etc.
In other words if all emitted CO2 would have remained in the atmosphere its concentration should be today at 456 ppm.
Without emission by artificially burning fossil fuels and making cement there is no great possibility that the CO2 concentration would have changed in such a significant manner.
This is why I consider this as non-controversial.
Like I and many other people on this website say AGW is a belief not a science, because there is no supporting evidence, not for the last 18 years anyway.
This review by Charles Moore in today’s Telegraph explains the social and economic reasons why this belief is being perpetuated.
http://www.telegraph.co.uk/culture/books/non_fictionreviews/10748667/The-game-is-up-for-climate-change-believers.html