People send me stuff.
Reader Kurt writes:
I just found your excellent website and have book marked it and will visit it often for updates. One simple question the global warm-mongers have never been able to answer is…
…that if in fact warming is taking place as they claim, what then is the optimum temperature of the Earth? Can they give us a number? is it 55 degrees? 78 degrees? 85 degrees? 98.6? Al Gore says the Earth has a fever – then what is the “normal” temperature?
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I thought about that long and hard, and thought to myself that it is sort of like a “Goldilocks” subjective temperature for porridge:
At the table in the kitchen, there were three bowls of porridge. Goldilocks was hungry. She tasted the porridge from the first bowl.
“This porridge is too hot!” she exclaimed.
So, she tasted the porridge from the second bowl.
“This porridge is too cold,” she said
So, she tasted the last bowl of porridge.
“Ahhh, this porridge is just right,” she said happily and she ate it all up.
But what is “just right” for Earth’s temperature? Depending on who you might ask, I suspect you’d get different answers.
The Neanderthals, who lived through the last ice age, 10,000 to 70,000 years ago, might say “uggghaa bok mak!” or in present language “warmer than it is now!”.
Ancient Greece, living in their age of enlightenment, which flourished during the 5th to 4th centuries BC might remark “είναι σωστό τώρα, τον πολιτισμό μας ευδοκιμεί” or “it is correct now, our civilization is thriving”.
The Romans, who lived through the Roman Warm Period from 250 BC to 400 might say “frigus quam praesens placere” or “cooler than the present please”.
During the Islamic Golden Age of expansion, 622-750AD, They might argue the temperature was “just right” for them.
In the Medieval Warm Period, from about AD 950 to 1250, when humanity started to thrive, they would probably say the porridge was “just right”.
Right after that, the Vikings in Greenland would probably have asked Onan Odin for some extra warmth.
During the Little ice Age, from 1300-1850 it would seem certain most people would ask for it to be warmer, especially since it had such a well documented negative effect on human history.
As for now for 1850 to present? Well, it just safe to call it the tail end of the Holocene Climatic Optimum although some people think it is too warm and are actively campaigning to reduce Earth’s temperature.
After thinking about how those previous civilizations in time might perceive their preferred temperature, and thinking about Kurt’s question, I realized that it might very well be an intractable problem, aka the Gordian Knot:
“Turn him to any cause of policy,
The Gordian Knot of it he will unloose,
Familiar as his garter”
(Shakespeare, Henry V, Act 1 Scene 1. 45–47)
Or as Dr. Judith Curry once remarked to Congress:
Climate change can be categorized as a “wicked problem.”
As to the answer to Kurt’s question, the best answer I can offer would be this:
A temperature at which the widely geographically varied and widely climate adapted human civilizations and cultures can go about their lives without undue hardship.
But what is that optimum “just right” temperature numerically? Well, first it is a local-versus-global problem. A local temperature suitable for the Eskimos isn’t likely to be suitable for the indigenous people of the Amazon. Second, it is a question of global average.
The average temperature of the Earth is said to have been and is:
Between 1961 and 1990, the annual average temperature for the globe was around 57.2°F (14.0°C), according to the World Meteorological Organization.
In 2011, the global temperature was about 0.74°F (0.41°C) above that long-term average, according to the WMO’s estimates.
Source: UCAR/NCAR
So if we are to accept those numbers, our current global temperature is 57.2 + 0.7 = 57.9°F
Between 1961 and the present, Earth’s human population has gone from 3 billion to 7 billion, more than doubling, and in that time the global temperature changed only 0.7F according to UCAR/NCAR. Given the population growth, you could say that slight temperature rise has increased the human condition to a more favorable environment.
But, honestly, I don’t think the global temperature matters much in the scheme of things, because despite gloom and doom predictions of global warming to kill millions by 2030, the projections are still upwards:
![pop_005[1]](http://wattsupwiththat.files.wordpress.com/2013/01/pop_0051.gif)
I think it is science and adaptation that matters more than global temperature:
![World_Population_Chart[1]](http://wattsupwiththat.files.wordpress.com/2013/01/world_population_chart1.jpg)
Source: http://econosystemics.com/AphetaBlog/?p=9
So probably, the best path forward from here is to shrug our shoulders at global warming, and to simply adapt, as mitigation (given the performance we’ve seen from current schemes to reduce Earth’s temperature) will be a true Gordian knot that will likely bankrupt us in the process.
Besides, our current warming from posited greenhouse gas effects may actually be helpful to us, because in climatic terms, there’s this maxim of mine:
If you don’t like the Earth’s climate, just wait a millennium.
And that is not too far ahead it seems, E.M Smith writes in Annoying Lead Time Graph
This graph from TheInconvenientSkeptic bothers me.
It bothers me because of what it says.
What it says, by two different modes of reading, is that we have no business being warm right now…
![LI-Holocene[1]](http://wattsupwiththat.files.wordpress.com/2013/01/li-holocene1.png)
Click to enlarge
I think most of us have puzzled over this questions. The problem is, it is all and always relative to who and where they are when you ask. I still say this one number that attempts to represent all is essentially a meaningless value that is interpreted to mean what ever the observer desires it. We and others are obsessing over nothing important. We should all get on with learning to live with the conditions we find ourselves in the true optimum is the one that nets “Me” the most gain and the least expense.
Steven Mosher says:
January 1, 2013 at 12:25 pm
Steven,
The question should be “What was the optimum temperature at which humans evolved?” Clearly it has nothing to do with “global average” as humans did not evolve all over the globe but in a warm climate. Therefore, I would put forth the argument that we humans need a warmer climate naturally without regard to how we have managed to adapt to colder climates with technology. Warmer is clearly better for us. Of course I may be a bit prejudiced since I just returned from a comfortable afternoon sitting outside a local bar relaxing in shorts while downing several tall glasses of my favorite beer (Stella).
John West says:
January 1, 2013 at 1:29 pm
““that we have no business being warm right now…”
A better statement IMO as opposed to the one quoted above would be:
That we are likely to be as warm as we are only by the thinest margin of thermal resistance, favorable albedo, and favorable shorter and longer scale forcing alignments such as solar spectral variations. An unfortunate confluence of unfavorable (to warmth) shorter and longer scale drivers could lead to a relatively rapid (geologically speaking) decent into glacial conditions. ”
ChiefIO also said in the post from where the graph comes:
“All in all, this graph tells me that we are on the knife edge of a drop into a cold stage and acceleration into a glacial stage, from which we can not recover.”
http://chiefio.wordpress.com/
Contrarywise, consider the effect of stereotypical temperature on resident cultures. Mañana, for instance, will kill in Northern Europe. Perhaps related is the correlation of First and Third World countries with cannabis tolerance.
Samuel P. Huntington’s Clash of Civilizations — And the Remaking of World Order.
Atmospheric temperature is not a measure atmospheric heat content nor is it a reliable indication of human comfort. An 80°F day in Orlando with 50% relative humidity (RH) is hot and muggy but a 80°F day with 5% RH is a pleasant spring day in Phoenix.
When water evaporates into air the temperature of the air is reduced but the total energy is the same. The evaporated water (called vapor) represents “latent heat” which is released when the vapor condenses to form liquid water again. The total heat of a sample of air is the sum of its sensible heat (which we feel as “hot”) and its latent heat (which we feel as “muggy”). This total heat is called enthalpy and it’s expressed in units of British Thermal Units per pound of air and water vapor mixture (Btu/lb). One Btu is the amount of heat required to heat one pound of water by one degree Fahrenheit.
The latent heat represented by water vapor is considerable. For example, moist air at 72°F and 30% RH (typical room air) has an enthalpy of 23 Btu/lb but 72°F dry air has an enthalpy of only 17 Btu/lb. The dry air would have to be heated to 95°F to reach the same enthalpy as the moist air.
Another example: the 80°F and 50% RH day in Orlando has a total heat content (enthalpy) of 31 Btu/lb. In the Phoenix desert, air at 115°F and 5% RH would also have an enthalpy of 31 Btu/lb but it’s 35°F hotter!
This phenomenon does not only occur in places that are spatially separated and have dramatically different climatology. For example, over a period of a few days in Los Angeles the temperature varied from 76°F to 56°F (20°F change) when total heat content (enthalpy) was constant at 22 Btu/lb. In the afternoon it was 76°F and 18% RH, then in the evening some moist air moved into the area and it as 56°F with 80% RH. Both conditions have an enthalpy of 22 Btu/lb.
Increased temperature (alone) is not evidence heating because temperature is not a measurement of, or a proxy for, the total heat content of atmospheric air. The global temperature history tells us nothing about any warming that might be caused by CO2 because greenhouse warming implies additional heat and the global temperature record, alone, doesn’t tell us if there is more or less heat.
The global average temperature is about 60°F. The GISS global temperature record shows an increase of 1°F since 1880. If global humidity fell by just 3% (global drying) the total energy of the global atmosphere could have been unchanged.
James Davidson gave a nice explanation.
The warming effect of CO2 is dwarfed by and lost within the massive Water Vapour Convection Cycle.
I think we should start referring to Warmists as WVCC ‘deniers’!
I know, let’s put it to a global vote. Then we can decide the best temperature to 0.1 deg C and just implement.
While I agree with Mosher that the question is ill posed, I can’t see how his observations did more than obstrucate the issue even further. There are perhaps “boundary conditions” that we can identify. For example, the point at which there is no longer ice melt in summer. Over successive generations the US and Europe would end up covered in ice. No doubt there are other “boundary conditions” on the warm side too.
However, putting that aside, the key issue is not about “ideal” temperature, but rate of change. If warming (or cooling) is gradual enough to allow for adaptation, especially with regard to agricultural production, then things will be fine. If the UN needs a goal it should not be a “2C” max or whatever, but rather a limit to the maximum rate of change per century.
Crosspatch warns to watch for “a persistent Aleutian Low brought storms across California, Nevada and Utah year-round, not just in winter.”
As it did last summer in Nevada (which was freaky) after temps finally rose to seasonal norms in July.
“…that if in fact warming is taking place as they claim, what then is the optimum temperature of the Earth? ”
It seems a lot people like coastal climate- milder conditions.
I think if Sahara desert had more rainfall, the people there wouldn’t complain too much.
Russia and Canada probably happier with milder winters- and a bit more rain.
So I think more rain of the non-flooding vast quantity variety in various areas would be an improvement.
So in term of temperature generally probably a warmer oceans would be better.
Janice says:
January 1, 2013 at 12:56 pm
Steve, one could also ask, “What is the optimum CO2 level for our world?” However, the problem with trying to answer a question like that also leads one back to the optimum temperature question….
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I think you are incorrect on that.
We can actually calculate the minimum optimum CO2. That optimum would be enough CO2 that WHEN, not if the earth sinks back into glaciation there is enough CO2 left to support C3 plants such as trees rice and wheat.
First we know the earth was flirting with a dangerously low level of CO2. Second there are
Chemical Laws for Distribution of CO2 in Nature
Therefore the reverse would be true. A cooling of sea water by 12 degrees C warming would DECREASE the CO2 concentration by ~ 150ppm.
The temperature spread from glacial to interglacial is between 8 to 12C graph
Since I would like to see the 400 ppm needed for good C3 crop food production and drought resistance that means a minimum level at this time of 650 ppm. (The more the better) If humans are dealing with a decreased crop production area, shorter seasons and drought, the last thing we need is CO2 starvation on top of it!
BACKGROUND:
@ur momisugly DirkH
Oh, if only I had ChiefIO’s brevity and clarity. Thanks.
mpainter says:
“A warmer world means a better world. It means milder winters rather than hotter summers. It means a lower heating bill and less snow and ice. Life flourishes in a warmer world. Cooling is the scythe of death.
Unfortunately the benefits of a warmer world are not to be ours. There was some hope that we could achieve this heaven on earth by burning fossil fuels, but the abysmal failure of AGW theory makes it clear that this will not happen. And now we see a cooling trend setting in.”
This is a great comment and certain to give CAGW cult members an apoplectic fit. Returning to the temperatures experienced during the ‘Holocene climate optimum’ of 6-8,000 years ago would undoubtedly make the world a better place in which to live.
I am never quite sure what global temperature CAGW cult members would like to see, but circa 1850 seems like a good bet. At that temperature profile, global famine would once again be widespread.
In our house my wife says it’s too cold and I say it’s too warm. She is of course correct and in one fell swoop the “Goredian Knot” is cut.
@David L. Hagen says:
January 1, 2013 at 2:16 pm
“Since humans survived the last glaciation and thrived during the warm periods, the “best” temperature is
between the glacial period temperature andthe Holocene climatic optimum.”Seems to me all the other temperatures were less than optimum, but I’m open to persuasive argument.
Matt says:
January 1, 2013 at 1:20 pm
Would it be getting too warm, at least within short time, if, say, species would go extinct and habitats shifting north? …
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Since it is actually getting cooler overall that is really the wrong question. Look at the last graph! The upper boundary of warm via geologic evidence is no more than two degrees hotter during the other interglacials graph Cold on the other hand is 8 to 10C cooler with a mile of Ice sitting on Chicago.
@Ingvar: Marvellous indeed. James Burke is a genius; I can listen to him any time. He can be wrong or vague in details (and sometimes very wrong about something big — for example, I feel embarrassed listening to his explanation of refrigeration), but he casts his net wide and the amount of stuff he trawls in is simply unbelievable, especially if you consider that most of it comes from old libraries.
Also, check out his more recent book, “Circles”.
Matt says:
January 1, 2013 at 1:20 pm
Would it be getting too warm, at least within short time, if, say, species would go extinct and habitats shifting north? Would that indicate a non – normal temperature even without knowing what is “optimal”?
() yes
() no
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Matt, please tell me during which period in the history of the earth species weren’t going extinct and habitats weren’t changing.
I’ll wait patiently for your answer. Until then, I will note that on the earth where I live I don’t believe there to have been such a time. Oh, and that extinction can rarely be tied directly to one and only one variable. Not on my earth.
Who cares about global temperature when the local temperature is right.
Our ancestors, tribes, settled where the condition were right and moved on when it went bad. I guess we are beyond the point to move easily even we could travel a long distance quite easily but we have our settlement (cities) build too large.
I also don’t think Al Gore and all the others would leave everything behind and that’s why they demand to change the climate for them.
Sure, if you lived in the Sahara but not if you lived in Arkansas. The lower Midwestern US and Southwestern US were in raging megadrought during that time. We would have active sand dunes crossing Kansas if we had those temperatures today though other areas that are currently dry would see more rain as the ITCZ moved to higher latitudes.
JohnH says:
January 1, 2013 at 1:05 pm
@Steve Mosher
My degree in physics has taught me at least one thing: no single variable in an extremely complex system can be ignored.
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Why has no one considered partial pressure? Increasing CO2 in the atmosphere will reduce the partial pressure of water vapor. Basic physics. Since H2O is a stronger GHG than CO2, increasing CO2 will if anything reduce warming due to GHG.
The assumption that CO2 causes warming is just that, an assumption that relies on ignoring contrary evidence, including natural variability. The paleo records show that CO2 is the result, not the cause of warming.
@Steven Mosher
“At 800 ppm, the evidence suggests, we get a world that is somewhere between 17C and 19C, if not warmer. ”
REPLY
There is no evidence that suggests such a thing, even below for this range requires generally more than 1000ppm. Only 2 periods where this range occurred with lower than 400ppm and it shows now we are still way off. Over millions of years there is no link between CO2 and temperature.
http://deforestation.geologist-1011.net/PhanerozoicCO2-Temperatures.png
The 3.7W/m2 is claimed for a doubling of CO2, yet 324 W/m2 is claimed for all greenhouse back radiation. A doubling of CO2 therefore is just 1.1% of the total. If 33c represents the total for greenhouse gases this just represents 0.36c rise per doubling of CO2. This is being generous because most of the warming from greenhouse gases occurs in the first parts with it being logarithmic. This also doesn’t take a water body into account either on the surface. Increasing evidence that the feedback is negative not positive.
There is obviously some disagreement here compared with the theoretical 1c per doubling CO2. The reason is obviously because this is partly derived from ideas over land not the ocean. The 324 W/m2 claimed for all greenhouse gases doesn’t warm a bucket of water in the shade during one day, so 1.1 percent of this even if atmospheric levels in future were reached are so miniscule. No wonder we can’t measure the difference from zero now with many decades until the possibility for a doubling of CO2 is reached.
Since the 1960’s CO2 levels have raised 80ppm until now so a doubling of CO2 won’t occur until it hits 630ppm. That means we are 25.4% of the target for a doubling of CO2. Therefore CO2 should have since the 1960’s only warmed the planet by 0.09c. Based on this there would be only 0.55c warming at most when reached 800ppm.
Mike Roddy says:
January 1, 2013 at 2:22 pm
Interesting question. The issue is less what is the optimum temperature for humans, but what the crops and creatures we survive from will require. The pace of warming and additional GHG’s is currently very rapid….
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Not it is not LOOK at the last graph. Overall the EARTH IS COOLING.
On the short term there has been no statistically significant warming for well over a decade while CO2 AND CROP YIELD per ACRE have increased. A win-win situation.
clipe says:
January 1, 2013 at 2:25 pm
Meanwhile, back in the day.
http://members.shaw.ca/wellandwx/blizzard77.htm
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Good Grief, I remember that blizzard very well! I had 2 fifty pound sacks of sand in my trunk and a shovel. We used them to get the semi-truck stuck across the plant parking lot entrance going so everyone could leave for home. That drive was a real nightmare.
Yeah. I know there is no answer,but who says there MUST be an optimum? Below one temp,mammalian bodies freeze. Okay.But what is the top temp? When do we incinerate? Just curious for the New Year.