A simple proof:
as a person familiar with both mathematics and computer science, this variation is not odd, in fact it’s completely understandable. After all a computer model is based on the best possible guesses from the available data and hurricanes are “complex natural phenomena that involve multiple interacting processes” so there is nothing at all odd about there being a 850 mile variation as to where it will it. As we get closer to Sunday and we have true data to input the variation in the models will correspondingly decrease.
Now apply this to climate change models telling us we face disaster in 100 years.
You aren’t dealing with a single “complex natural phenomena that involve multiple interacting processes” you are dealing with EVERY complex natural phenomena that involve multiple interacting processes that exists on the earth. Every single additional item you add increases the variation of the data models. Furthermore you are also dealing with variations in the sun, variations in the orbits of the earth, its moon and more.
And that’s just the variations in natural phenomena, imagine the variation in industrial output on the entire planet for a period of 50 or 100 years.
Think of the computer modeling and tracking of that single hurricane and apply this thinking to the climate of the earth as a whole. How accurate that model is going to be over 100 years, 50 years, 25 years or even ten years?
Would you be willing to bet even your short term economic future on it, would anyone in their right mind do so?
Not me.
But climate models are much better at predicting things in the long term. We know this because climate scientists invented a time machine.
A PBS “news” interview with a climate scientist elicited from that worthy an interesting and useful analogy. During the “juiced ball” era of major league baseball, (so we were told) steroid abuse among the players resulted in an unusually, unnaturally, high number of home runs. It is impossible by looking at any one homer to determine and say whether or not steroid abuse “caused” the home run. Nevertheless, he said, it is inarguable that more home runs were caused — as a foreseeable and deliberate consequence from the abuse of performance enhancing drugs.
The journalist did NOT then ask how it could come to pass that major league baseball might play 12 seasons with a LOWER-than- historically-typical number of home runs, given that detectable steroid use and abuse increased during that same period. Which would be the analogous question to ask if baseball, steroids and homers are analogous to climate, carbon dioxide, and hurricanes.
I, as a viewer, restraining myself from pitching a fast moving object or swinging a heavy club into the TV screen. I even avoided charging the mound. I was however — and THIS is newsworthy — better impressed by the integrity of the climate scientist than I was the competence of the journalist. Kudos to MARSHALL SHEPHERD, University of Georgia. (I wonder if he studied hurricanes alongside Judith Curry? )
You don’t need to model every atom to be able to do a simple classical mechanics problem either do you? I also think global warming is bad science, but just because you can’t model a mid-scale problem accurately it doesn’t mean you can’t model a large-scale problem accurately.
“You don’t need to model every atom to be able to do a simple classical mechanics problem either do you?”
Don’t you? Open loop extrapolation of even a simple mechanical problem often diverges from reality, which is why we typically update projections with observations in practical applications.
Eventually, your extrapolations will diverge. The question is, how fast and how far? It is very dependent on the application, and how well you have modeled it. And, I have zero faith that activist scientists have modeled things very well at al.
How fast and how far — the Lyapunov exponent https://en.wikipedia.org/wiki/Lyapunov_exponent
Paradoxically, positive feedback in the Carbon Cycle — the warmer it is the more CO2 emission form soil, tundra, permafrost, oceans — means that the atmospheric CO2 level is more stable and less of human-caused emission remains there.
Why? If there is a thermally stimulated component to CO2 emission, the sensitivity of plants to increased concentration in absorbing CO2 must be greater, otherwise the “numbers don’t tie up” to give the current levels of CO2.
Our mutual nemesis Ferdinand Englebeen cites Pieter Tans, who I guess is the go-to expert on the Carbon Cycle in polite society. My simulation runs of the carbon cycle, taking into account the non-linear “Revelle Buffer” absorption of CO2 in ocean water as well as a 2-compartment ocean model, agree with “consensus science” that half of human-emitted CO2 ends in the atmosphere, the other half about equally divided between ocean and terrestrial “sinks” and that nearly all of the increase in atmospheric CO2 is the result of human emissions.
This model does not account for the large year-to-year variability in net CO2 emissions (additions) to the atmosphere. If you add a source of thermally stimulated emission that is uniform over time scales to account for the Wood for Trees dot com data, only half the increase in atmospheric CO2 up past 400 ppm can be blamed on humans, the other half is the consequence that yes, as a matter of fact it has been getting warmer.
Pieter Tans, bless him, explains this away, claiming that the thermally stimulated CO2 emission only works on short time scales because it is the fluctuation in the short time it takes tropical-forest leaf litter to get completely rotted and its CO2 returned to the atmosphere. He offers hand-wavy support in his version of Salby-esque cross-correlation functions.
Where I am stuck is how there can be fluctuation in rotting of leaves on any time scale, that as a result of any imbalance, doesn’t result in an accumulated store of carbon (the organic content of the soil), where the thermal emission acts uniformly across time scales because that reservoir is far from ever being fully depleted.
I am still trying to “wrap my head” around how Pieter Tans and in turn Ferdinand could be even plausibly correct about the tropical leaf litter-gets-consumed-completely-after-a-couple-years, contributing the fluctuations in the Wood for Trees plot without thermal stimulation occurring over longer time scales.
On the other hand, if Pieter Tans is correct, there is no thermal stimulation of CO2 occurring now that could “run away” into a catastrophic positive feedback. After having studied the Carbon Cycle, I am a uniformitarian — if there is a carbon emission CO2 mechanism apart from the tropical leaf-litter system that is self-limiting on account of depletion of the leaves by rotting, it would be occurring here and now — it would not suddenly “cut in” from some “tipping point.”
I don’t think the atmosphere warms Earth.
I don’t think adding a larger atmosphere on Mars could warm
Mars.
I think a way to warm Mars is to add an ocean in the tropics of Mars.
Now, doing so could cause there to be more water vapor, but I don’t this water vapor warms Mars, rather I think the ocean warms Mars.
Mars currently has 28 times more CO2 per square meter as compared to Earth. Mars also has 210 ppm of water vapor. And these greenhouse gases aren’t warming Mars.
Now if you add an ocean in tropics of Mars this could result in doubling the amount of water vapor- so instead of 210, it could be +400 ppm.
So if follow greenhouse effect theory, what warming should you get if you double the concentration of water vapor on Mars?
I doubt any one can give estimate- because the Greenhouse Effect theory is pseudo. Or you don’t know how water vapor on Earth is causing warming according to the “theory”. Wiki:
“By their percentage contribution to the greenhouse effect on Earth the four major gases are:
water vapor, 36–70%
carbon dioxide, 9–26%
methane, 4–9%
ozone, 3–7% ”
And these greenhouse gases are suppose to cause all warming and they have total warming effect of 33 K.
Is that useful to you, if so how much warming is caused if you double the amount of water vapor on Mars?
Earth currently has about 3% water vapor in the tropics and less than 1 % outside the tropics. Or in terms ppm about 30,000 ppm in tropics.
Some of the believer of GHE think that without CO2 being a forcing greenhouse gas, one would not get water vapor, and basically CO2 alone causes the 33 K of warming. Or doubling of CO2 causes about 1 C increase, such warming allows more water vapor to be in the atmosphere, and water vapor causes warming, which allows atmosphere have more water vapor, which does more warming, etc- a runaway effect.
This part of reason why I doubt you can use this theory to tell you how much doubling Mars water vapor, will do in terms of warming Mars.
Now if you believe in this theory, one could easily doubt one can add water vapor to the Mars atmosphere. This because you are brainwashed.
I just want to add water, and I realize the water will evaporate- that result is actually a cost that rather not have. I just don’t think it’s necessarily a huge cost as compare to the cost of making domes to prevent the water loss from evaporation.
Or what think is hard is making the case that not a lot water will evaporate. So, I make that case, now.
So we going to use cold water, and perhaps the water will need to have ice at the surface. And if there is ice rather than cold water, it’s still going to evaporate.
Anyhow I think it would water rather than ice, plus I think eventually it might be warmer water. So could start with the water not getting warmer than 10 C and could get to point of water being less than 20 C.
Depending on pressure on Mars water boils at about 10 C.
And have a square lake 10 km by 10 km and 20 meters deep- volume of water 100 times .02 is 2 cubic km of water or 2 billion tonnes of water. Or if water is 1 million dollars per tonne [$1000 per kg] it’s 2000 trillion dollars worth of water. Or for what I have in mind, Mars water will need to be much cheaper than $1000 per kg. Or roughly needs to be about 1/100th of the cost or about $10 per kg.
But I would argue that for there to be any kind of Mars settlements, one needs the price of water to be $10 per kg [or much less]. Anyhow if $10 per kg it’s still 10,000 per ton and thousand dollar more than people on Earth pay for water. Or US uses 600 billion tons of water per year and at 10,000 per ton, that 6000 trillion dollar to use that much water ten times more the US GDP- or quite simply not economical.
Anyways at $10,000 per ton it’s 20 trillion dollar. And still pretty far from being economical, but also it’s a big lake. There no reason start a settlement with this much water, but if looking more than 100,000 settlers it’s not a lot of water.
Say one settler buys as lifetime use of water of 10,000 tons- it’s 100 million dollar of water. Times 100,000 settlers is 10 trillion dollar. Or half the water is bought. It doesn’t change the fact very expensive water.
Getting to the point one has 10 km square lake and will say it’s temperature is 5 C and stay at 5 C year long. How much water will evaporate in a year.
Could evaporate more than 1 meter depth per year? or 100 million tonnes of water lost per year.
Let’s look at how much water vapor is in the atmosphere. So 210 ppm is .02 percent. there 25 trillion tonnes of atmosphere so about 5 billion tonnes, so if adding and if kept in atmosphere adding 1/50th to 210 ppm.
Now, obviously 20 km square area is small vs Mars tropical region- or about 58 million square km , vs 400 square km.
Now happens if add 4 more of these 20 km lakes which are 5 km away from the first one- so 58 million square vs 2000 square km of water surface.
If you lose 100 tonnes when add the 4 other ones, the first one should have less than 100 tonnes loss per year. And repeat having more around it, and it continue to loss less.
Or when have the one 20 km square probably most of water isn’t going to get very far from lake. and may 1/1000th of it gets to the poles.
If add 1000 of these 20 square km lakes [400,000 square km vs 58 million square km] One might have something like 1/100th of evaporated water from each 20 km square getting to the poles- or 1 ton per year per square getting to the poles, and all of them evaporating less than 100 tonnes per year.
Also 1 so square added 1/50th to amount of water in atmosphere, times 1000 which maybe reduced 1/2 of loss, and somewhere around doubling the amount of water vapor. And having 1000 tons of water freezing out at poles [and tens thousands freezing out elsewhere on Mars. Having 500 tons of water sublimating on poles might be small effect, but it will cause some warming of the poles, and will also cause some warming elsewhere. But we also have covered the surface of tropics with- it’s about 1/50th or less..
Of course at this scale, water has to be abundant and very cheap- maybe a low as 100 times the cost of water on Earth.
Now the other obvious objection is that the average global temperature of Mars is -50 to -60 C and how can you possibly have liquid water on mars which is 5 C or warmer.
One just say the lake have nuclear reactor and it has waste heat. But that’s cheating.
Instead I would argue that sunlight warms the lakes, and if sunlight warms the lakes, that increases the average temperature of Mars.
First we go back to Earth, Earth has average temperature of 15 C. And it’s 15 C because the tropics has average temperature of 28 C- outside of tropics earth’s average temperature is about 5 C.
And as everyone knows the tropics warms the rest of the Earth.
Mars like Earth is already warmer in the tropics than outside of the tropics. And think by adding water to the Mars tropics it will become warmer than it already is.
Now the other obvious objection is that the average global temperature of Mars is -50 to -60 C and how can you possibly have liquid water on mars which is 5 C or warmer.
What about the atmospheric pressure?
-Now the other obvious objection is that the average global temperature of Mars is -50 to -60 C and how can you possibly have liquid water on mars which is 5 C or warmer.
What about the atmospheric pressure?-
If you double Mars water vapor, this by itself doesn’t add much mass to atmosphere and doesn’t increase Mars pressure.
The warming effect of a Mars tropical ocean is mostly confined to tropics.
One would replace CO2 sublimation with H20 sublimation. Or right now it seems one has both H20 and CO2 sublimation on Mars, but there is more CO2 sublimation as compared to H20, and with doubling water vapor, one get more water sublimation as compared to CO2 sublimation. And reducing the amount of CO2 sublimation could allow more CO2 to remain as atmosphere- thereby have higher atmosphere pressure.
Warming tropics in terms of average air temperature could cause out gassing of H20 and CO2.
But generally it seems it’s increase of pressure of about 50% mostly due replacing CO2 sublimation with H20 and warmer air having less sublimation of CO2.
One could want water to boil or get close to boiling. Or when water expensive, one would avoid it, but at point of having tropical mars ocean, water has to be quite cheap. Or solar ponds are used on earth for mining, and one could use solar ponds on Mars for mining- though the solar ponds on mars would be much cooler than 80 C solar ponds on Earth. Or solar ponds couple meter deep and 80 C requires close to 1 atm of pressure. So say, could around 30 C, or in Hellas basin as high as 40 C. And/or solar ponds might used to mine permafrost outside the tropic such as in Hellas basin.
Anyways at moment there are places which water doesn’t boil at 10 C [such as Hellas basin] , and it seems where Curiosity rover is at, could have water not boil at somewhere near 5 C.:
https://mars.nasa.gov/msl/mission/instruments/environsensors/rems/
Earth, 2017-08-30 UTC
Sol 1801
Air Temperature:
-21 C Max. -80 C Min
Ground Temperature;
-3Max. -87 Min
882 PA [8.82 millibars]
Which is in Mars tropics
Oh bits of previous attempt to post that wasn’t posted:
-…And with mars air gets cold rapidly just meters above surface- and having more water vapor should lessen this effect. And water vapor changes Earth lapse rate and should change Mars lapse rate. Hmm.
On to Vikings:
“When the southern cap was largest, the mean daily pressure observed by Viking Lander 1 was as low as 6.8 millibars; at other times of the year it was as high as 9.0 millibars. The pressures at the Viking Lander 2 site were 7.3 and 10.8 millibars.”
Viking 2: Landing site 22.27°N 47.95°W [tropics]
And:
“In contrast, the diurnal temperatures at the northern landing site (Viking Lander 2) during midwinter dust storms varied as little as 4°C (7°F) on some days. The lowest predawn temperature was -120°C (-184°F), about the frost point of carbon dioxide. A thin layer of water frost covered the ground around Viking Lander 2 each winter.”
http://astro.if.ufrgs.br/solar/vikingfs.htm
And viking 2: Landing site 47.64°N 225.71°W” [not tropics]
So wouldn’t get that Co2 forming- though instead could/would get water ice- which has much more latent heat.
Carbon dioxide 574
Water 2257 (kJ/kg)
…-
oh, mistakes:
-Viking 2: Landing site 22.27°N 47.95°W [tropics]- should be:
Viking 1: Landing site 22.27°N 47.95°W [tropics]
And from quoted article:
“about the frost point of carbon dioxide. A thin layer of water frost covered the ground around Viking Lander 2 each winter”
I didn’t notice they said “thin layer of water frost”
I think it was mostly CO2 frost, but also with some water frost- or that was and is my assumption.
Mars has 8.9 time the mass of CO2 in its atmosphere as the Earth has in its – 54 times as much per unit area. From a warming perspective, Mars has to be maxed out vis-a-vis CO2. And it has so little water that that is not a factor. It seems like an ideal test bed for CO2 driven warming models. I see only resistance when I suggest it.
I thought the number was closer to 28 times the amount of CO2 rather than 54 times as much per unit area.
But just roughly figured it. I guess the main difference is how many trillions of tons of CO2 is in Earth’s atmosphere.
Mars has about 25 trillion tonnes, so that means
25 / 8.9 = 2.8
So, you think Earth has 2.8 trillion tonnes of CO2 in it’s atmosphere.
And as recall I thought it was more than this, it was more than 3 trillion. It was years ago. I also remember some number for ppm, so check that:
“Atmospheric CO2 levels are expressed in parts per million by volume (ppm). To convert from ppm to gigatonne of carbon, the conversion tables of the Carbon Dioxide Information Analysis Center advise that 1 part per million of atmospheric CO2 is equivalent to 2.13 Gigatonnes Carbon. Using our 44 over 12 rule, this means 1ppm = 7.81 Gigatonnes of Carbon Dioxide.”
https://www.skepticalscience.com/print.php?r=45
It’s not exactly as recall it, but let’s use it.
So got about 400 ppm 400 times 7.81 is 3.124 trillion tonnes.
I remember using 8 but thought it was 8 ton for 2 ppm or something.
Another:
‘So, that 40 billion tons of extra carbon dioxide we dump into the air every year is accumulating at a rate of 2 parts per million when you look at the entire atmosphere.”
http://www.slate.com/blogs/bad_astronomy/2014/08/20/atmospheric_co2_humans_put_40_billion_tons_into_the_air_annually.html
So put 40 in but 1/2 or less stays or 20 billion equals 2 ppm or
10 billion per 1 ppm.
Another:
” I would simply observe 1 ppm CO2 = 2.12 Gt carbon or 7.76 Gt CO2. ”
I guess I probably did use 1 ppm for 8 tonnes.
But problem with this is that earth doesn’t have 400 ppm of CO2 in it’s atmosphere, rather this is amount measured at high elevation on high mountain, because CO2 levels are more uniform.
So I probably rounded it up to 8 per ppm.
But in any case, somewhere around 3 trillion and this doesn’t seem
like answer to the difference as thought it would be.
Earth has something like 510 million square km
Or 510 million million square meters. 5.1 x 10^14 meters
and 3.0 x 10^15 kg of CO2 Or 30 / 5.1 is 5.88 kg of CO2 per square meter.
In entire atmosphere of 10,000 kg per square meter.
Mars has 144.8 million square km or
1.4 x 10^14 square meter and 25 trillion tonnes or 2.5 x 10^16
Or 250 / 1.4 is 178.57 kg of CO2 per square meter.
And 178.57 / 5.88 kg is 30.36 times more CO2 on Mars vs Earth.
So I had assumed it was 28 times and you said 54 times.
Checking in after a long absence to see if nihilism still prevailed here. Yep.
Climate is not weather (for the billionth time); the disposal of a single hurricane does not significantly influence the energy balance of the Earth, while doubling CO2 does – the expression of the latter will have an affect that is simpler to estimate as one integrates over time and space just because of thermodynamics; while the former could end up anywhere in the Atlantic with no thermodynamic repercussions in a week. Its hard to predict, because from the point of view of the climate system, it doesn’t matter.
The unknown industrial related CO2 output over the next century is of course the very thing the modeling exercise seeks to inform – which is why the IPCC uses a variety of scenarios for output. The climate modeling (with respect to the various economic scenarios) is likely to be vastly more reliable than the economic predictions of disaster from significant CO2 emission reductions. Its interesting how skeptics get all bent out shape with climate models (which are at least based on the laws of physics and observation bound), while running wild with economic intuition on the impacts of mitigation.
“…the expression of the latter will have an affect that is simpler to estimate as one integrates over time and space just because of thermodynamics…”
Nonsense. This is a statement of faith, with no compelling evidence to confirm. We have not even begun to plumb the depths of feedback – action and reaction – in this ultra-complex system, which can render any expectations based on simple, decoupled, essentially back-of-the-envelope models, null and void in a heartbeat.
Checking in after a long absence to see if nihilism still prevailed here.
I knew there was no point in reading further after that little gem.
Dale Carnegie wrote a book for you.
—Duncan Young
September 2, 2017 at 2:11 PM
Checking in after a long absence to see if nihilism still prevailed here. Yep.
Climate is not weather (for the billionth time); the disposal of a single hurricane does not significantly influence the energy balance of the Earth, while doubling CO2 does – the expression of the latter will have an affect that is simpler to estimate as one integrates over time and space just because of thermodynamics; while the former could end up anywhere in the Atlantic with no thermodynamic repercussions in a week. Its hard to predict, because from the point of view of the climate system, it doesn’t matter.–
Oh, a number of things. First it’s the heat of oceans which power hurricanes. Everyone knows this. Or it’s said the ocean water at depth [+ten of meter] needs to be about 28 C:
“Sea surface temperatures must be 82 degrees Fahrenheit (F) or warmer for tropical cyclone formation and sustenance.”
https://www.nasa.gov/vision/earth/environment/HURRICANE_RECIPE.html
10 meters of water is same mass of atmosphere. 10 meter of water depth is 1 atm of pressure.
10 meter of ocean at 28 C has far more energy the the atmosphere above it. Or 4.18 times more energy per ton per K degree.
Or air is 1 and water is 4.18 in terms of specific heat- specific heat is based on atmosphere being 1 and water has specific heat of water is
“Precisely, water has to absorb 4.184 Joules of heat for the temperature of one gram of water to increase 1 degree celsius (°C). For comparison sake, it only takes 0.385 Joules of heat to raise 1 gram of copper 1°C.Dec 2, 2016”
https://water.usgs.gov/edu/heat-capacity.html
and the atmopshere isn’t vaguely close to 28 C or decreases about 6.5 C per 1000 meters of elevation and half the mass of atmosphere is above 5000 meters in elevation. so 5 times 6.5 C is is -32.5 C to air’s temperature, and hottest air temperature ever gets is about 50 C at sea level elevation. And average air temperature at sea level is about 15 C and average global temperature of ocean and ocean air temperature is
about 17 C- or since ocean cover 70% of earth surface, this higher temperature account for average of 15 C which the land surface have lower average temperature [despite land surface able to have the highest air temperature of around 50 C [and ocean highest possible is about 35 C].
So roughly the 10 tens of the ocean hold about 5 times more energy than atmosphere could hold. And amount of ocean water warmer than the atmosphere is around 100 meter deep.
Anyhow everyone knows the ocean store much more heat than atmosphere.
The ocean depth are warmed by the shortwave radiation of the sun, longwave radiation can not warm below 1 mm of the ocean surface.
So if Co2 has any effect on most of the surface of Earth, it could only increase evaporation and highest temperature of ocean surface is 35 C, meaning can only warm air to 35 C.
But since ocean does have huge amount of evaporation, it’s unlikely CO2 is doing much to warm the top 1 mm of the ocean. Or Co2 must have very small effect upon Earth average temperature. And thing like dew would rapidly evaporate. Or it wouldn’t require sunlight to evaporate the dew.
” We have not even begun to plumb the depths of feedback – action and reaction – in this ultra-complex system, which can render any expectations based on simple, decoupled, essentially back-of-the-envelope models, null and void in a heartbeat.”
This would be the statement of faith, the whine that it is just too hard. If you haven’t, say, read the IPCC physical basis report or something similar, you would be the one taking your claim on faith (https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter01_FINAL.pdf). Compared to the physics of a combustion chamber the bulk behavior is pretty straight forward. There is a 100 years of scientific literature on radiative forcing that explains the modern average surface temperatures of all the planets quite well, once the gross properties are known. You cant get around a) the basic laws of thermodynamics (all that energy from the sun must be accounted for); b) the knowledge that skeptics keep bringing up, that there has been considerable natural variability in the past – but then ignore that implies that the Earth’s climate is not in some magic super-buffered state, but is susceptible to forcings (you cant rely on feed backs can save you); c) we have good, testable hypotheses for the major events of variability we see in that past that involve changes in atmospheric composition; and d) greenhouse gas emissions are a forcing (by definition), and have increased over the last century due to easily quantifiable human activity. The statement of faith here is that somehow it will come out in the wash, ’cause climate so complex, so lets shrug and keep chugging along. And the other statement of faith is that any attempt to accommodate that will be immensely disruptive to the economy, which of course is a nice linear predictable dumb system which will inevitably collapse if a particular century old technology is reduced in scope (/sarcasm)
The real issue here is neither scientific or economic; it’s political. And politics is to economics as weather is to climate; truly complex, unpredictable, and in the long run of limited impact, but has the capacity to leave many causalities. One interpretation is that climate change skepticism as manifest here and other parts of the internet is primary a form of identity politics, a way of striking back against perceived smug technocratic elites (and to be fair, the center parties of the West do have an abundance of smug technocratic elites) through a shared mythology (remember that one time in the 70’s they said there would be ice ages!). Those elites have lost the trust of a significant minority of the electorate, both through the elites own mythology of competitive meritocracy and ‘justified’ monopoly, and through deliberate underminding of trust via skulduggery by individual, highly interested, concentrations of wealth; and climate change skepticism is a symptom of that (as is GMO/vaccine skepticism, with nominal politics reversed). Nothing unites a community like contempt, just as nothing is as manipulable as contempt.
The odds that I have changed any minds are extremely small, of course; but like any complex system, gotta have some feedback…
All scientific projection based upon Greenhouse effect theory about future global temperature increases have been wrong.
The most well known proponent of global warming is Al Gore, who is an idiot.
During last 1/2 billion years , earth average temperature has has been warmer than 15 C.
Earth’s present low average temperature is related to Earth being in icebox climate and we are presently in an interglacial period, which is period much warmer than the glacial periods which can last for more than 100,000 years.
Earth’s average temperature during the interglacial period has been around 15 C- though during the Holocene Optimum- wiki, “The Holocene Climate Optimum (HCO) was a warm period during roughly the interval 9,000 to 5,000 years BP.” it was bit warmer than 15 C. And during the last glacier period global temperature were 5 to 10 C cooler than the current average temperature.
Or earth average temperature during it’s current icebox climate is about 10 C. And during most of last 1/2 billion years earth average temperature has been about 20 C.
There no reason to assume earth average temperature was about 5 to 10 C due to greenhouse gases. There no reason to assume we are in icebox climate because of greenhouse gases. And no reason to assume that when earth isn’t in icebox climate and it’s global average temperature is about 25 C, that such temperature are due to greenhouse gases.
And icebox climate is defined as earth having cold oceans and having polar ice caps. Or cold oceans and ice caps is usual conditions over the last 1/2 billion years.
Or what is normal over last 1/2 billion years is warm oceans and no ice caps.
So to be clear Earth ocean has average temperature of about 3 C, and during last interglacial period: wiki:
“The Eemian (also called the last interglacial, Sangamonian, Ipswichian, Mikulin, Kaydaky, Valdivia or Riss-Würm) was the interglacial period which began about 130,000 years ago and ended about 115,000 years ago.”
Earth oceans were couple degrees warmer, and of course still had ice caps, and sea levels were about 6 meters higher.
Geologically there was little difference the the present Holocene and the Eemian- continents in same place [basically] same mountains, etc.
Humans existed but they were primitive- they had stone age technology and didn’t farm nor have cities. There was some biological difference, but mainly it was a cultural difference. There was cultural difference even between modern [last few centuries] primitive people and the human ancestral species living in the time of the Eemian.
But it’s possible that these “humans” imagined they had some effect upon the weather and climate. Or the modern human have always thought they affected weather and climate.
“Nothing unites a community like contempt.”
I could not agree with you more, but sure-shootin’ there is more than enough contempt in multiple communities (many sides?) to go around.
Two data points in my “life journey” on the Climate Change question.
The first is the guy-in-a-wheelchair (just like a recurring character on the TV X-files) telling me we are “all going to die if we don’t go all-out for nuclear power.” At least he was earnest because the idea that we can decarbonize without nuclear power is a whole ‘nother politically influenced show.
This was on a rather small but nicely landscaped college campus somewhere in Pasadena, California. The time was in the early 1980s. The guy was a climate modeler, and the sense I got was that on the basis of his modelling experiments based on the sort of bulk energy flows you speak of, he knew that he was going against a “consensus” that was influenced by “we are all going to die from freezing” that was a “thing” in the late 1970s. The temperature guys were saying it will get cold, the energy-balance modelling guys were saying it will get too hot — is it plausible that the broad based consensus on hot came later in history?
The second is that there was some old European guy who came to give a seminar talk in a building on Dayton Street in Madison, Wisconsin. I wish I kept notes on these things to remember when within my over 30 years spent a couple blocks down on the other side of Randall Street when this took place.
They guy was offering his “back-of-the-envelope” calculations of the very sort of energy balance explanation of why each of the planets in the solar system are at the temperature they are at. In other words, he was going for really “bulk” properties of the system rather than even the sort of detail incorporated in a GCM. The purpose of his exercise was a “sanity check” of the GCMs. His model came up with a projection of warming that was at the very low end of what the models are predicting as reported by the IPCC.
What was interesting about the talk was what didn’t happen. The people attending the talk listened politely and asked polite questions. The person giving the talk was not denounced as being in the pay of the Oil Companies, of denying the Impending Crisis or any number of things. That someone could use the energy balance equations and make some assumptions about how energy is transferred in the atmospheric system (heat largely flows from the tropics towards the higher latitudes through atmospheric circulation, where it is drier at the poles and can better radiate back to space?), that someone could do such a thing and be received politely and not denounced for saying the “warming will probably not be that bad” was an amazing thing.
In terms of a community united by contempt, could that talk take place on a major university campus today? The guy was doing everything right according to your statement, he was considering energy transfer and energy balance in “the large”, he came up with human-caused warming but at the low end of what people are worried about.
Not a statement of faith. Of logic. It is not possible to create an imbalance larger than one’s proportionate share of the inputs upon which said balance depends. Our inputs are proportionately quite small.
It’s a slam dunk. We are not appreciably affecting atmospheric CO2 levels. It is overwhelmingly dependent on temperatures:
http://woodfortrees.org/plot/esrl-co2/mean:12/from:1979/derivative/plot/uah6/scale:0.175/offset:0.142
Eventually, this will be realized, after this silly Chicken Little episode has run its course.
I sometimes wondered what the meteorologists meant when, discussing an evolving hurricane, they used the phrase “the models are beginning to converge.” That means something different in my world, but it’s crystal clear now that no two models start out with the same multi-day prediction. They “converge” to a common solution only when the domain of integration is small enough. Proof indeed!
So you don’t think it means having a model for say jet stream or direction of low pressure system- or models for various parts of weather?