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
Where ever the perfect ‘global’ temperature might be, here is some examples of why carbon dioxide levels are not the ‘climate control levers’:
1. Oct. 9, 2009
Last Time Carbon Dioxide Levels Were This High: 15 Million Years Ago, Scientists Report
“The last time carbon dioxide levels were apparently as high as they are today — and were sustained at those levels — global temperatures were 5 to 10 degrees Fahrenheit higher than they are today, the sea level was approximately 75 to 120 feet higher than today, there was no permanent sea ice cap in the Arctic and very little ice on Antarctica and Greenland,” said the paper’s lead author, Aradhna Tripati, a UCLA assistant professor in the department of Earth and space sciences and the department of atmospheric and oceanic sciences.”
[ http://www.sciencedaily.com/releases/2009/10/091008152242.htm ]
Now, that description of our planet is nothing like that of today. Obviously.
In 100 years? Maybe. It (climate) better get a kick-a-long as highest CO2 levels are NOW.
2.
December 31, 2012 – Dust Bowl memories stir across the US Great Plains
A wave of dust storms during the 1930s* crippled agriculture over a vast area of the Great Plains and led to an exodus of people, many to California, dramatised in John Steinbeck’s novel “The Grapes of Wrath.”
While few people believe it could get that bad again, the new storms have some experts worried that similar conditions – if not the catastrophic environmental disaster of the 1930s – are returning to parts of Texas, Oklahoma, New Mexico, Kansas and Colorado.
[ http://www.theage.com.au/environment/climate-change/dust-bowl-memories-stir-across-the-us-great-plains-20121231-2c1ym.html ]
* Levels of carbon dioxide in 1930, Mauna Loa Observatory in Hawaii: 287ppm
[ http://dwb.unl.edu/calculators/pdf/trendsco2.pdf ]
If we are returning to “similar conditions – if not the catastrophic environmental disaster of the 1930s “, BUT carbon dioxide levels are now ONE THIRD higher,
Again, carbon dioxide can not be the cause.
3.
Finally, the one observed climate event that blows all the catastrophic global warming computer models up:
April 27, 2012 – It’s official: Australia no longer in drought
[ http://www.theage.com.au/environment/weather/its-official-australia-no-longer-in-drought-20120427-1xpsp.html ]
No one saw that coming. Least of all the government funded alarmists:
2008: This drought may never break
“Perhaps we should call it our new climate,” said the Bureau of Meteorology’s head of climate analysis, David Jones.
[ http://www.smh.com.au/news/environment/this-drought-may-never-break/2008/01/03/1198949986473.html ]
James Davidson says: January 1, 2013 at 11:51 am
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Then whence the Ice Age, with all these fine, immutable laws of radiation physics and impecable calculations? Seems like a big piece of the puzzle is missing, and I mean big. When theoretical physicists make their pronouncements about climate,they are sitting ducks.
Janice says:
January 1, 2013 at 7:27 pm
“I would actually like to see crocodiles frolicking in warm water at the north pole, also, but since there isn’t a land mass there currently that could be hard on the crocodiles. Cheers.”
Thought that myself, but elected to avoid it as there is in the general vernacular of the arctic north pole plenty of shoreline for frolicking: Maybe with the less hairy polar bears that eat alligator eggs for breakfast and the young alligators for brunch.
crosspatch says:
January 1, 2013 at 8:02 pm
“The average temperature of Alaska has fallen 2.4F since 2000. This year is looking to be another bone-chiller:”
Add that to the winter low temps that are declining in the lower 48. Those UHI highs are scewing the data toward warming.
This question always seems to be strange to me as there is such a wide variety of climates that people live in today, from Alaska to the Sonoran desert in the US alone.
It is interesting that from a quick view of the world’s fastest growing cities and urban areas that they all seem to be in warm regions.
http://www.citymayors.com/statistics/urban_growth1.html
Okay, maybe there won’t be crocs in the Arctic but we can build a lot of golf courses in the Antarctic!
Steve Keohane says:
January 1, 2013 at 11:41 am,
Steve K,
Here is a place where some of your questions can be answered and John Kehr wrote a book that deals with the subject quite well.
The current interglacial is actually 16,000 years long but enjoyed the warming side of insolation for just 12,500 years and that ended about 3,500 years ago and still declining as glaciers have in recent centuries re appeared after long absence.
http://theinconvenientskeptic.com/wp-content/uploads/2012/01/Chap_8-Illustration_64-550×393.png
The rest of the page of great charts and some glaciers that have been born fairly recently due solely to the declining insolation trend. It is worth a visit as they are based on published science data:
http://theinconvenientskeptic.com/chapters-8-10/
We are deep into climate Autumn and soon enter Glacial Winter
All I can say to that is “oh well”. We built our amazing 20th century infrastructure KNOWING that sea levels globally were higher when the Roman Empire was at its peak. We should have expected them to possibly return to those levels. Therefore we are stupid, and can’t now complain about naturally rising sea levels.
And while we are at it, what exactly was the consensus of the last really big question as to how many angels can dance on the head of a pin ?
I think the Neanderthals would disagree with your assessment. They thrived when it was colder and would argue for a colder climate. In fact the Neanderthals may be clamoring for a colder climate.now.
Two comments:
How did they know the global temperature in the 70’s when the first Earth resources satellites didn’t get launched until 1979? There was no way to get the temperature over vast areas of the Earth before then.
Also, I recall reading that 8 of the past 11 ice incursions (ice ages) were preceeded by periods of warming. Could be were headed for another deep freeze!
I think the alarmists are generally more worried about the rate of change then the absolute temperature, they say that humans and the ecology cant adapt to such rapid change as is projected (eg cities swamped by rising seas, forest cover changing to fast etc).
But I would say its the bureacrats themselves who most worry about the rate of change, not the people, or the rest of the biota.
From Yes Minister:
“there has been movement, in a topic in which the civil service generally hopes there will be no movement”
“the civil service generally hopes there will be no movement in any topic”.
Janice says:
January 1, 2013 at 7:27 pm
As an aside, I actually would like to see about 2000 ppm CO2, as that optimizes plant growth very nicely. However, when I mention that much CO2 some people appear to go into cardiac arrest.
But should they stop breathing, apply artificial respiration. That has 40,000 ppm CO2 and it could revive them. Just do not let them know that your exhaled air has 4% CO2.
Humans faced near extinction during the last glacial period. The planet is colder and drier during the glacial period. The biosphere expands when the planet is warmer and contracts when it is colder. During the Wisconsin glacial period all of Canada, the Northern US states and Northern Europe are covered with an ice sheet.
Human near extinction 70 kyr ago.
http://zeitlerweb.com/about-2/human-near-extinction/
Human beings may have had a brush with extinction 70,000 years ago, an extensive genetic study suggests. The human population at that time was reduced to small isolated groups in Africa, apparently because of drought, according to an analysis released Thursday. The report notes that a separate study by researchers at Stanford University estimated the number of early humans may have shrunk as low as 2,000 before numbers began to expand again in the early Stone Age.
Features of Evolution and Expansion of Modern Humans, Inferred from Genomewide Microsatellite Markers
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1180270/
Curiously interglacial periods end abruptly rather than gradually.
http://www.esd.ornl.gov/projects/qen/transit.html
According to the marine records, the Eemian interglacial ended with a rapid cooling event about 110,000 years ago (e.g., Imbrie et al., 1984; Martinson et al., 1987), which also shows up in ice cores and pollen records from across Eurasia. From a relatively high resolution core in the North Atlantic. Adkins et al. (1997) suggested that the final cooling event took less than 400 years, and it might have been much more rapid.
The event at 8200 ka is the most striking sudden cooling event during the Holocene, giving widespread cool, dry conditions lasting perhaps 200 years before a rapid return to climates warmer and generally moister than the present. This event is clearly detectable in the Greenland ice cores, where the cooling seems to have been about half-way as severe as the Younger Dryas-to-Holocene difference (Alley et al., 1997; Mayewski et al., 1997). No detailed assessment of the speed of change involved seems to have been made within the literature (though it should be possible to make such assessments from the ice core record), but the short duration of these events at least suggests changes that took only a few decades or less to occur.
1000 ppm huh? You are pretty much saying that humans have the ability to quadruple C02 concentration all by themselves ( ~250 ppm before oil right? ). I should know better than to ask you these once again, but (1) if every single CO2 ppm rise since 1850 comes from human beings, and (2) every single fractional degree of alleged temperature rise is also from humans … well you should just come right out and admit what you have just said, and that is that we are supposed to be locked in the Little Ice Age and that because of our actions using oil and coal have screwed it all up. Say it Steven. Say we are supposed to be freezing. Eco-lunacy.
One problem with living in the theoretical exclusively is that you have disconnected your self from reality, for example: “And who decides?”. Ummm, not us. Not you. Not your AGW hoaxster buddies either. You have a bit of a God complex ( as does Fuller’s similar grandiose thinking ) to think we get to sit around and decide how a future world heats itself and stays warm. You see, you and Fuller actually believe that people can plan the future for example somehow sequestering the coal and oil in the ground, and then capturing sunshine, wind, rainbows and unicorns instead. Reality is what you need to visit every so often. By kneecapping the USA oil and coal industries all you accomplish is to hurt the people needing warmth in the present, and are guaranteeing that future people will go and get those resources later because you have made them even more valuable than they are now. In fact you eco-loons have guaranteed that the USA will eventually become the new Kuwait or Saudi, rolling in oil and coal centuries from now because of the actions today where we will just use up the supply from the middle east and other places in the meantime. You are building the future USA energy empire ( bet that wasn’t your agenda, was it? )
You cannot stop future people from picking the low-hanging fruit of oil and coal, especially if they are cold future people who are going to laugh at the argument that we must not mine coal and oil because using it will heat the planet! Humans will burn through the oil and coal supply ( which may not really be finite anyway ) as long as it makes sense. And more bad news for your naive world view is those future cold people will get this sequestered energy even if they need to conquer the areas where it is hidden. That is human history. Your ideas are fantasy land.
The paleo record has periods when the planet was cold and CO2 was high and periods when the planet was warm and CO2 levels were low. This is indication that the CO2 mechanism saturates.
Atmospheric carbon dioxide levels for the last 500 million years
http://www.pnas.org/content/99/7/4167.full
Using a variety of sedimentological criteria, Frakes et al. (18) have concluded that Earth’s climate has cycled several times between warm and cool modes for roughly the last 600 My. Recent work by Veizer et al. (28), based on measurements of oxygen isotopes in calcite and aragonite shells, appears to confirm the existence of these long-period (_135 My) climatic fluctuations. Changes in CO2 levels are usually assumed to be among the dominant mechanisms driving such long-term climate change (29).
Superficially, this observation would seem to imply that pCO2 does not exert dominant control on Earth’s climate at time scales greater than about 10 My. A wealth of evidence, however, suggests that pCO2 exerts at least some control [see Crowley and Berner (30) for a recent review]. Fig. 4 cannot by itself refute this assumption. Instead, it simply shows that the ‘‘null hypothesis’’ that pCO2 and climate are unrelated cannot be rejected on the basis of this evidence alone.
http://www.nature.com/uidfinder/10.1038/nature01087
Despite these successes in linking variations in greenhouse gas concentrations to climate change in the geologic past, the oxygen isotope palaeotemperature record from 600 Myr ago to the present displays notable intervals for which inferred temperatures and pCO2 levels are not correlated1. One of these occurred during the early to middle Miocene (about 17 Myr ago), a time well established as a warm interval (relative to today), but with proxy evidence for low atmospheric pCO2 (ref. 2). Moreover, whereas climate models predict tropical warming in response to elevated pCO2, geologic data — in particularly the oxygen isotope record — indicate muted warming or even cooling at low latitudes while higher latitudes warm (the ‘cool tropicsparadox’10–11).
The ice epochs correlate with changes in GCR as the solar system passes through the spiral arms of the Milky Way galaxy.
Celestial driver of Phanerozoic climate?
http://www.phys.huji.ac.il/~shaviv/Ice-ages/GSAToday.pdf
Celestial driver of Phanerozoic climate?
We find that at least 66% of the variance in the paleotemperature trend could be attributed to CRF variations likely due to solar system passages through the spiral arms of the galaxy. Assuming that the entire residual variance in temperature is due solely to the CO2 greenhouse effect, we propose a tentative upper limit to the long-term “equilibrium” warming effect of CO2, one which is potentially lower than that based on general
circulation models.
The following is link to Shaviv defending is analysis of meteorites to determine how GCR has varied in the deep past. As Shaviv shows the ice epochs correlate with long term increases in GCR that occur when the solar system passes through the spiral arms of the Milky Way galaxy.
http://www.phys.huji.ac.il/~shaviv/ClimateDebate/RahmReply/RahmReply.html
RECONSTRUCTING COSMIC RAY FLUXES —The starting point of SV03 is a reconstruction of cosmic ray fluxes over the past 1,000 Myr based on 50 iron meteorites and a simple model estimating cosmic ray flux (CRF) induced by the Earth’s passage through Galactic spiral arms ([Shaviv, 2002; Shaviv, 2003]). About 20 of the meteorites, making four clusters, date from the past 520 Myr, the time span analyzed in SV03. The meteorites are dated by analysing isotopic changes in their matter due to cosmic ray exposure (CRE dating [Eugster, 2003]). An apparent age clustering of these meteorites is then interpreted not as a collision-related clustering in their real ages but as an indication of fluctuations in cosmic ray flux (CRF). One difficulty with this interpretation is that variations in CRF intensity would equally affect all types of meteorites. Instead, the ages of different types of iron meteorites cluster at different times [Wieler, 2002]. Hence, most specialists on meteorite CRE ages interpret the clusters as the result of collision processes of parent bodies, as they do for stony meteorites (ages _ 130 Myr) to which more than one dating method can be applied.
Many, many thanks for the plant-CO2 links. I had been wondering lately If there was some minimum atmospheric CO2 level, both for adequate plant production (as food for us animals), and as an absolute minimum where photosynthesis would drop below where animal (and all) life could be sustained. Your links provide at least a place to start.
CO2 @ur momisugly 2000ppm? Be careful what you wish for: During the Carboniferous, several degrees warmer than now, life on earth never had it so good. All that carbon which we’re now mining so industriously was living, breathing, mega-scaled life – club mosses the size of trees, spiders the size of snow saucers, dragonflies the size of hang gliders. Could a relatively small, active, exothermic mammal like H.Sap – the product of an ice age – compete in such a riotous ecology? There may a hint in that humans living in the tropics never managed to create advanced, technocratic societies on their own – too much competition, especially from the critters that are invisisble to the naked eye.
Interesting question and an interesting discussion. It strikes me as a much more difficult question to answer than ‘What is the optimal level of taxation’
and we aint doing too well answering that one either
Well, I finally got through all the comments. Lucky for me, several of the things I thought needed to be “brought up” have been. Thanks, especially, to DirkH for pointing out that the comment about “we have no business being warm” was a “jumping off point” to look at why, and finding that it’s related to lag times, and that the present level of insolation is very compatible with an Ice Age Glacial, but only barely compatible with holding present warmth. That ANY perturbation downward tips us into a glacial, but perturbations upward are strongly limited (too little sunshine 65 N and the only way to get even 2 C warmer in interglacials is via an ‘overshoot’ when rapidly warming that is immediately smacked down with cold. There is no tipping point to warm, but rather strong negative feedback. There is a tipping point, but only into a glacial.
The article further explores some of the why and how (and comments do too). Mostly “it’s the water”. We have hot / cold cycles as the Thermo Haline Circulation stutters. There is a bi-modal stability, with most stable being frozen glacial almost all the time, lesser stability is only when insolation 65 N is higher than at present. Basically we barely get enough insolation peak to have an interglacial happen (and it only happens via melting the polar ice cap… ) and that level of insolation is now past.
In between (i.e. now) we are ‘metastable’, but as we are presently warmish, the only direction we can go to any significant degree is down. Cold. Frozen. There is an occasional ‘flutter’ to the Gulf Stream (on geologic time scales) that can put warming spikes during a glacial, but they can’t ‘latch up’ and don’t stick. Stable is frozen at any insolation level other than peak interglacial (which, as noted, is past). Once we get down to 416 W/m^2 or so, that is low enough to force the glacial onset all on its own. We are presently about 428 W/m^2. So any perturbation of about 12 W/m^2 down even for a short period of time tips us into albedo and ocean current feedbacks that lock us up into a glacial for the next 120,000 years.
So any volcano surge. Any significant rock fall from space. Any solar / lunar modulation of the ocean system and clouds. Our present insolation is very compatible with glacials and we have been in glacials at this level and do not rise out of them. So once anything starts the ice and snow covering too much, or once we have “persistent multiyear ice” in the Arctic; we’re toast… or rather, ice creamed…
One bit of “good news” is that pollen and sediment data for Florida indicate a confirmation of a model paper (in the link) and show that part of the ‘lock up’ is a slowing of the Gulf Stream and that the salty layer starts sinking south of Iceland (i.e. doesn’t get the heat to the Arctic). Basically, a melting Arctic is key to holding the glacial at bay. BUT, when it comes, the flow backs up. This means that while Canada and N. Europe / UK are a bit screwed; places like Florida and the “Desert Southwest” of the USA do better. Basically, even a full on glacial isn’t cold everywhere. Florida, in fact, gets about twice as wide and has nice warm weather. (So y’all make plans to come on down! 😉 The “Desert Southwest” becomes a bit wetter too, so more grows there.
The other “good news” is that while temperatures can ‘latch up’ in a couple of decades, it takes 100,000 years or so of mass transport to make the glacial shield miles thick all the way down to Chicago… You can walk more in one day per year than it moves. So seasonal snow goes up fast, but the ice takes a very long time. Plenty of time for your children, grandchildren, and great grand children to “move on”. ( I figured it as about 15 miles / generation… on average. Some times will be like the LIA and “bang” you want to be 300 miles more south, but that’s a cyclical overlay on the trend. So one or two generations moves 300 or 150 miles, then you have 20 generations of ‘not moving’, then one moves again… ) Since in my parents lifetime they moved about 12,000 miles and 2,000 miles each, and I’ve moved 210 miles south of where they ended up, that’s not exactly a big deal these days.
FWIW, if we are very very lucky, we can likely squeeze an added thousand or 2 or so years out of this present status (IFF no volcanic surge, rock fall, etc.) and then there’s a tiny bit of added insolation, and in several more thousand after that we hit the “aw shit” downturn that is just too much. So if we are very very lucky, CO2 or soot on ice or whatever will keep us just a tiny bit more warm than otherwise, and we don’t go to Popsicle land. If CO2 is a complete dud, or a Sleepy Sun makes the cloud cover thicker and snows a little more persistent (i.e. LIA redux) then it’s all over but the simpering…
Oh, and if you look at that bottom graph, notice it looks like the insolation curve is offset a couple of temperature bars? That implies we’ve got a few more thousand years of ‘cooling’ built in to the solar forcing process yet to ‘catch up’. As cooling into a glacial is a 10,000 to 100,000 year scale process, and has a rapid 5000 and 1500 year cycles on top of it, that implies the next LIA is already “on the cards” as the cycles turn, and we better hope it is no worse than the last one… That red line is continuing ‘down slope’ and we are lagging it…
To answer the question from the posting: “What is optimum”? It isn’t possible. As others pointed out, there is no such thing as a ‘global average’ temperature. It may not be possible to calculate one that has any meaning at all.
http://chiefio.wordpress.com/2012/12/10/do-temperatures-have-a-mean/
Not as ‘cheeky’ as it sounds. This is in addition to the question of intrinsic properties not being something you can average and preserve meaning. ( That whole ‘entropy is not temperature’ point made so well above). This is just looking at the fact that the temperature record is more likely to have a non-standard normal distribution. One for which a ‘mean’ is not-defined.
So one ought to instead ask “What temperatures work well for people and wildlife?”. There we find anything from 130 F in the Arabian, Sahara, or California Deserts to -50 F in Siberia and Alaska. Life and people in all of them. So my answer is “Any”. (Though generally there is a lot more life in a Tropical Rainforest than any where else… so warmer and wetter and more CO2 makes for more total happy life). Given the large flux of folks who run to the Tropics any chance they get, I’d say about “Florida Springtime” is ideal. Though San Diego has a lot of followers ( About 70 F more or less year round. Something like 65 – 75 F typical, you can grow bananas, but rarely above 90 F) Los Angeles is hotter and more folks like it. Nome Alaska not so much… 😉
@RAYQ MCMULLEN G: LOVE that cartoon!
@Steven Mosher:
“The question of ‘what is the optimum temperature for the earth’ is an ill posed question.”
You ought to have stopped there… It IS an ill posed question. (What in Buddhist classes gets you whacked with a stick and MU! stated… which roughly means “That is a nonsense question. Try again.” “The question is ill formed.”)
Yet that is EXACTLY the question being held up as critical and central to the CAGW Thesis. Their thesis demands the implicit answer of “The temperature in 1970-1980” (or so). Else there is no crisis…
Per the rest of what you said, it looks like folks have addressed that. I also note the “Drive By” style persisting. No further engagement since… Too bad, but I understand. I sometimes can’t “hang out” as much as I’d like either.
Just note, though, that given our present insolation status, we can’t get back to the Holocene Optimum level of warmth. Just not possible. We’re barely hanging onto what we’ve got. The insolation changes and ocean current changes drive this wagon, and CO2 at most whispers in their ear… and those changes have moved against warmth. In prior interglacials, we whacked into 2 C warmer with even more insolation at peak and immediately shot back down again. We now have less insolation 65N, so it just can’t happen. Add that the ocean has gone cold, the Gulf Stream is slowed down, and we’ve got the present snow coloring “outside the lines” of climatology, and it’s not looking at all good for that warming up scare.
http://chiefio.wordpress.com/2012/12/18/about-that-snow-cover/
With a newer snow cover graph here with even more snow cover:
http://moe.met.fsu.edu/snow/
And no, we’re not getting more snow because it’s warmer. From Alaska to Siberia and China it’s colder. Even as far south as Thailand is feeling a chill. This is a good old traditional quiet sun PDO / AMO flipped cold cycle. Nothing to do with CO2, everything to do with natural weather cycles of 60 year length and solar cycles of longer 178 or so length. CO2 can’t stop the tides and can’t wake up the sun.
@Matt:
MU!
We have a weather cycle of 60 years, another one of 1500 years, and a 5000 or so lunar tidal driven cycle. Species always go extinct, but rarely from such things as shifting weather, mostly from predation, poor competition, being eaten or having evolution obsolete them. 6 million years ago grasses evolved and the forests of East Africa receded making life very hard from some ‘semi-chimps’. They ALL went extinct… but some of their children changed into a different species. That species is us. Every single species that makes us human is extinct. We are not the same species any more. Get over it. The megafauna of north America of about 10,000 years ago snuffed it when a giant impact event caused the Younger Dryas. It also killed off the Clovis People and cleared the way for Asian types to fill most of the continent.
http://chiefio.wordpress.com/2012/12/22/native-americans-and-european-roots/
So not much you can do to stop rock falls from space, glacials and ice sheets, evolution of new diseases and predation by the newest hot hunter. Yes, I’d like to save every single species on the planet. Not going to happen though. They will evolve, and they will change. Those grasses, for example, resulted in a whole lot of ‘browsers’ having problems (more silica so more tooth wear and harder to digest) but we got a lot of grazers instead. Panda Bear live on a giant grass, Bamboo. Would you say that the loss of those browse dependent species was bad? That the Panda is bad? And note that CO2 is not involved at all. When polar bears are wandering where Chicago had been, will that be bad for the species that live there now? It will happen. How will you stop it? Won’t that be bad for the Polar bear, enjoying the return of HIS natural habitat? (They evolved for the glacial…)
So you go try freezing time in a bottle. Me? I’m going to check out land prices in Florida and the “Desert” Southwest…
@All:
So many good comments, but it’s too late for me to say all I’d like. But thanks for the many interesting thoughts. The shifting baseline history in particular, and several others.
I’ll check back in tomorrow after I’ve had some sleep 😉
Gail Combs says:
January 1, 2013 at 3:02 pm
Gail, I agree with your take on atmospheric CO2 being essentially too low (and thus CAGW being even more insane – its worse than we thought!) One question – will currently rising CO2 have an effect on the ratio of grasslands to forests – is there any evidence already of forestation of grasslands? Or is this over-simplistic?
It is an honor and a thrill that my email has touched off such an amazing thread of thought-provoking debate. Of course, my question has no answer as there is no such thing as an optimum temperature, which means the case made by the warm-mongers is moot.
I grew up in Alaska where I suffered through many cold winters of minus 40 temps when I hoped and prayed for a little global warming. And from the latest news, I see it’s getting even colder. Of course Gore will turn this data inside-out to argue that global warming is causing the cooling.
Forget global warming, Alaska is headed for an ice age
http://www.alaskadispatch.com/article/forget-global-warming-alaska-headed-ice-age#comment-134871
‘But what is “just right” for Earth’s temperature?’
This question was actually answered in the 1972 sci fi film “Silent Running”, set in a future in which Earth’s last greenery has been shot into space and maintained there. Early in the film we learn that Earth’s entire surface is a uniform 75 degrees, making the “outside” effectively the same as “inside”. Sheldon Cooper would be pleased. 🙂
@Phlogiston:
I liked the article Gail wrote too… and I’m no Gail, but I think I can take a shot at answering your question:
That is over-simplistic.
There are many C4 plants and some do it for the water retention advantage, while for others it is faster growth or better tolerance of low CO2. Remove the CO2 low issue, the others remain.
Now trees are mostly pretty old species and especially in the temperate zone have little need for C4 metabolism Shading and water access (deep roots) are how they usually win. Even in the grasses, it tends to be tropical and desert grasses that are C4, so the grass in a temperate forest isn’t going to be all that advantaged… In the cool damp shade of a temperate forest, it’s fine for a C3 grass.
So only at a place ‘on the edge’ of a dry hot place where the C4 plants are competing with the C3 for relative dominance will added CO2 tip the fight, just a little. So where a hot dry scrub forest is grading into desert, the line might move a bit. Yet even that is more likely to be caused by local shifts of water with cyclical changes, so you would need to watch for a couple of hundred years to see who wins… ( a full PDO cycle is 60 years, to 2 or 3 times that to see the trend clearly…)
Take your typical Redwood fog forest or a snow pine forest, not going to show up much.
Oh, and there’s also CAM metabolism found in some cactus / succulent like plants, but that’s another metabolic story 😉
In short, though, there are many factors that go into competition and who wins is rarely tipped by just one or over a large area. (And that is usually a new pest or disease…)
Then there is the fact that typical ‘succession’ has things going from grass to brush to trees, and you have to put a time and fire / clearing metric on your grassland age too…
Steven Mosher says:
January 1, 2013 at 12:25 pm
… Consider now, that during the LGM when it 2C-4C cooler than today…
Where did you find that figure? A more common estimate is about 8 deg-C (ca. 14 deg-F) colder at the depth of the LGM about 20 kya. In fact, if 8 deg-C were mistaken for deg-F, the conversion would be to slightly more than 4 deg-C. A very quick and dirty real-world check can be made by comparing say mean annual high temps in Portland, Oregon and Sacramento, CA. You can use Eugene,Or was an alternative to Portland, but the result is the same. The difference is about 10 degrees F. Since, during the LGM biological zones were displaced about 1,000 to 1,200 km southerly in the western US, based upon fossil plant associations, that latitudinal distance is probably somewhat short (Tacoma would be a better match in terms of temperature difference) [Views of the Past: Essays in Old World Prehistory and Paleanthropology edited by Leslie G. Freeman, 1978, p. 373]. These changes are not nearly as neat as simple latitudinal shifts driven by temperature, since there were warmer refugia in the Seattle vicinity for instance. But the Sacramento Valley resembled the Willamette in terms of dominant plants (Oregon Oak, Doug. Fir, etc.). All the same, 2-4 deg-C is a very, very low estimate.
Well said, Blade.
Whatever the global climate does, we are in much better shape to deal with it than humans at any other time in history. There are wealthy and comfortable societies from chilly Canada to tropical Singapore. There are strains of plants and animals that we raise for food at both of those extremes as well. If it is economically worthwhile, we can protect the land against rising sea levels. If storms get worse, we have engineering solutions that build better structures.
As a non-scientist, I have always viewed the debate primarily in political and economic terms. Quite simply, even if the worst alarmist predictions are right (and I don’t see much evidence for that), we can deal with it. It’s just a matter of cost/benefit analysis, IMO.
Making energy more expensive and impoverishing people is never a solution to any problem affecting humans. The poor sods who lived through climate changes in earlier eras were greatly disadvantaged by their poverty and lack of cheap, reliable energy – not to mention primitive levels of technology. We are much more fortunate, and our grandchildren – about whom the doomsayers are so concerned – will be even more so unless the eco-fascists get their way.