A few days back I linked to a report that pushed back recorded climate history to some 650,000 years ago. In a nutshell, today’s greenhouses are completely off the charts as far as history goes.
I’ve posted one figure from the papers* that I think captures everything that I was trying to say in a fairly easy-to-digest format. It’s a big file, so click through the extended text to view it.
The time scale runs horizontally from the left to right, from zero thousand years ago (today) on the left to 650 thousand years ago on the right. The colored traces represent different measurements that the scientists made continuously down the length of the ice core. The purple line represents atmospheric temperature, which you estimate using oxygen isotopes. Working your way up, the next three lines represent different greenhouse gases, with nitrous oxide in navy, carbon dioxide in red and methane in light blue. If you start at 650,000 years ago and work left you can see a fairly regular rise and fall in each gas that correlates more or less with a rise and fall in the estimated atmospheric temperature. That’s the world coming in and out of ice ages. Now look at what happens when each greenhouse gas reaches the far left, corresponding to today. Cripes.
You can see another important point on this graph. Human civilization started anywhere between ten and fourteen thousand years ago, by which I mean centrally-governed populations with borders and urban centers; loose tribes with fire in caves go back much farther than that. If you look at the last few millimeters on the left side of the temperature record you can see that for ten thousand years we’ve had a surprisingly warm and stable climate. As far as civilization is concerned I don’t think that’s an accident.
Based in part on some ideas that Jared Diamond brought up in his Pulitzer Prize-winning book Guns, Germs and Steel, I think that we owe a good bit of our global success to that climate stability. If that’s the case then we won’t do civilization any favors if we manage to bring our current island of stability to an end. Looking at those crazy spikes at the far end of the greenhouse gas traces it’s hard to imagine how we won’t.

(*) Science vol. 310: pages 1313 and 1317
rilkefan
Nice plot, though an indication of the relative uncertainty between measurements would be nice (though on the other hand it’s easy enough to estimate by eye assuming local noise). When I first saw it I thought of many histograms of mine in which I’d made a mistake and lots of wrongly-treated data ended up in the zero bin. Looks like it’s “we’re making a mistake” instead.
Incidentally, I’ve heard it argued that civilization has caused local and global climate changes which have (so far) been mostly beneficial (well, except for the occasional desertification).
DougJ
This all sounds like junk science to me.
RSA
Nice (though for me slightly confusing) graph. Am I right in assuming that scientists have a pretty good grasp of the causal relationship between those gases and atmospheric temperature, at least in their usual ranges? Also, are the data detailed enough to show a significant cross correlation?
James Emerson
John…
Everytime you unearth a hockey stick by digging up prehistory…a troglodyte will suddenly appear proclaiming your head’s uncanny resemblance to a puck…
It’s a worthy fight, but be sure to keep your chinstrap tightened…
Tim F.
Yes and yes. The relationship between greenhouse gases and global temperature is simple physics. The data for the last 400,000 years at least has been cross-corroborated enough times to say fairly certainly that temperature and greenhouse gases correlate well.
The Disenfranchised Voter
I’d love to read that argument. Could you direct me to it?
RSA
Thanks. Dumb questions, now that I come to think of it. It’s the enormous time scale and the magnitude of recent changes that play with my intuitions.
KC
Tim F., I’m really glad John has had you step in during his “off” hours. Your beer-blog Fridays have been excellent and now you’ve out done yourself with this very colorful, readable, and somewhat disconcerting chart. Thanks.
rilkefan
TDV, ‘fraid I’m not that organized. I just recall the argument that the hockey-stick plot put us on a slight warming trend that kept Europe mostly out of mini-Ice Ages a la 1600 or whenever it was. You may be aware that the anti-global-warming crowd likes to say that losing a few feet of coastline would be worth the gains in liveability in Canada and Siberia and so forth.
Tim F.
I think that it’s perfectly reasonable to argue that civilization has modified the Earth in a way that perturbs the normal glacial-interglacial climate cycle. For example, we’re extremely good at replacing forest with grass, desert and scrubland. Soil erosion will have a big impact on ocean productivity near river mouths, and drier climates will put more dust in the air which will also blow over the ocean and stimulate production.
The problem is, it’s possible to have too much of a good thing. The last hundred years make me very nervous.
vinc
There’s nothing complicated about the idea that certain gases will warm the earth.
Super-brief explanation: the earth is warmed by the sun. Most of the sun’s energy that reaches the earth is in the form of visible light, where much of it is absorbed and turned into heat. Heat radiates back outward, mostly in the form of infrared light. The key thing is that carbon dioxide will not block visible light, but will block infrared light. So adding carbon dioxide to the atmosphere doesn’t stop energy from entering, but does stop energy from leaving.
Why does it do that? The explanation would require a bit of physics background–it’s not *too* complex, but it would require a pretty long post. You can take it as an experimental result, though. All of the above is completely uncontroversial.
So predicting that the earth will get warmer is simple. However, the question of how much warmer is a horrendously complicated one, because when you change the earth’s temperature by even one degree you change winds and currents and plant growth and glacier size and ocean acidity and the polar ice caps and cloud formation and dozens of other things, and all of these feedback to the temperature. And this is why you hear about hugely complex computer models–they’re trying to take all of these factors into account.
scs
Okay, this is probably a stupid question, but I am going to ask it anyway. Since the whole planet is consuming and burning organic material for energy constantly, (humans burn organic material for warmth and power, plus humans and animals eat and consume calories), are we eventually going to run out of organic material to consume? I’m thinking a little energy is lost in the process each time this consumption takes place. Or is the energy recaptured somehow in a perfect replacement cycle?
BlogReeder
I wish I was as smart as you. :)
I’ve read that as a green house gas, CO2 has nothing on water vapor. Is this true?
BlogReeder
The energy comes from the sun. That’s what chlorophyll is used for. In some locales (geothermal vent) the energy comes from other means.
Tim F.
Plants make new organic matter out of sunlight, water and carbon dioxide.
That’s absolutely true. One of the things that drives climate modelers batshit crazy is not knowing what exactly will happen with water vapor and clouds. Clouds reflect sunlight back into space, cooling the planet, while vapor absorbs it. In that regard your guess is almost as good as theirs.
scs
Well can’t we study from plant and animal and geological records to see what happened the last time the earth heated up? Like according to that graph above, about 130,000 years ago?
Tim, I think you are making faulty conclusions here, ala Behe. You can’t conclude that civilization necessarily developed because the climate was stable for 15,000 years, as there are so many other factors involved. Perhaps their were mutations around that time, perhaps there were developments in language, the use of the horse. Another reason is that maybe it was because the climate was just warmer overall, not necessarily that it was stable. After all, even the ice ages were probably ‘stable’ in that they were consistently cold for thousands of years, such as the ice age before our current warming, which seemed to be stable also for 10,000 years. So if I had to guess it would be the stability AND warmth that allowed Mediterranean peoples to start farming and develop.
Just for argument here, I really don’t think global warming on the long term will kill us off and might even benefit us. Yes we will lose costal regions over a thousand years or so, which will suck, and cause upheaval. But, the population shift will just go northward, where there is much more land available. So on balance, how is it THAT so deadly?
scs
Okay, well that answered it. So it follows that if someone could burn the whole planet down to a charcoal crisp, I guess somehow bacteria and then eventually plants would grow up again. Pretty interesting.
Frank
scs- 50% of humanity and much of civilization’s infrastructure reside within a few feet of sea level and near the sea. Plus I don’t think we are talking about 1000 years, more like 100 years.
Frank
I forgot to mention the much more exciting weather we should expect to experience from a hotter atmosphere and ocean.
scs
I don’t think it would take a hundred years to submerge the coast. Nothing is THAT quick. Okay, yes a lot live near sea level, but they would have to move back a few hundred miles where the new coastline is. Just like they are doing in Lousianna now. So it would cause upheaval to be sure, but we are modern enough to be able to accomplish those moves. Eventually, maybe after 500 years, wouldn’t having more arable land make up for all that?
scs
By the way, I’m not just saying this because I love global warming. I just think it’s apparent that climate change is inevitable and if we survive as a species we are going to have to learn how to adapt. For instance, the mesas of Arizona look like that because that whole area used to be an ocean. The 1000 lakes of Minnesota are there because they were carved out by glaciers that used to cover the all land there. So change will happen. I’m just trying to figure out how humanity will deal with it.
Tim F.
I’m not necessarily concluding, I’m just saying that I think so, and I have very good reason to think so. One problem is that we have a fairly tight balance between food production and not dying in a massive global wave of starvation. If climate shifts humanity can shift, yes. The problem is that global food production is geared towards conditions as they are today. Do you think that we can continue to feed the planet while we adjust? I’ll go out on a limb and answer that. No.
Google ‘Younger Dryas.’
Inertia, followed by panic, followed by war. It’s just who we are.
scs
Well I thinks it depends on whether we have warming or cooling.
According to you graph above, it looks like we are due for a nice looong period of ice age, because it seems there is an ice age every hundred thousand years and we’re almost through the warming. So if there is an ice age, that is a really bad thing because in a narrow band around the equator, the earth really doesn’t have that much land. I say start burning more fossil fuel now, in that case.
But if there is a warming, we will have much MORE land to farm as the bulk of land is north, closer to the artic, and the melting ice will only be enough to submerge the coasts. Since most of the farming takes place away from the coast, I don’t think it will really disrupt the food supplies that much. It will have economic repercussions of course which will effect food supplies indirectly. But yeah there will probably be wars with Canada and Russia as humanity tries to invade their countries to grab the arable land. Who knows. It will be interesting to be sure.
vinc
Yes.
If the earth had no atmosphere at all, it’s average temperature would be about -20 Celsius (about -5 Fahrenheit, or completely unsuitable for complex animals, let alone humans.)
The combined effect of water vapor, carbon dioxide, and a couple other greenhouse gases brings it up to 15 Celsius (60 F). Water does most of the warming, because there’s so much of it.
However, say we think of water as doing 90% of the warming, and C02 doing the rest. (The numbers in this paragraph are made up for illustration only–I don’t remember the real ones. But the ones in the last paragraph are legit.) Then water is responsible for 32 degrees and carbon dioxide for 3-4 degrees. Now we double the amount of carbon dioxide in the atmosphere (a reasonable estimate). Your guess would probably be that you’d double carbon’s effect, or get 3-4 C (~7 F) of warming. Obviously it’s hugely more complicated, but that’s a decent first guess. I did this calculation for real in a class I took several years ago, but my memories are kind of fuzzy…
It doesn’t take a big swing in average temperature to have HUGE effects. In the last ice age, the average global temperature was just 4 C lower than it is today. That was enough to bury most of the northern US under a mile of ice and bring sea levels down by 400 feet.
So even though CO2 doesn’t have a very large effect compared to water, it’s enough to have a huge effect from our point of view.
vinc
I think the question is not humanity’s survival or even civilization’s survival. It’s whether our lives will continue to be good or bad, whether we’ll have reliable food supplies or not, whether we’ll have to resettle one sixth of the world’s population because they live too close to the coasts, whether tropical diseases will extend their range up to Canada, and so on.
These are very bad things and it’s worth thinking hard about how likely they are to occur and what price we’re willing to pay to avoid them.
I don’t think the worst-case scenario above is terribly likely, but it’s likely enough that it’s worth taking reasonable measures to reduce our risk.
scs
Good info on CO2. However, I’m not sure I understand the graph then. It makes the temperature look like it takes huge swings from ice age to warming. I’m not sure how many degrees that means on the graph (what’s -380?) You just said it was about 4 degrees per swing. Okay, since the graph shows a huge increase in greenhouse gasses in recent years and yet the temperature has remained relatively constant, going with the regular cyclical pattern of the graph. How does this support the global warming theory then?
I’m also wondering if there are maps out there that show what the earth’s land would look like if all the ice melted. There probably are, I’ll have to google it.
scs
It’s not a question of “whether”. As we see from the graph above, it’s a question of “When”. Climate change will happen, with or without greenhouse gasses.
On another note – why is there a 100,000 year warming cycle? Does the sun do something every 100,000 years?
blogReeder
I hadn’t realized ‘Younger Dryas’ was the name. Ice age conditions came back about 11,000 years ago taking only 20 year to occur. It coincided with the extinction of the mega fauna (Mammoths, saber tooth tigers). Interesting. It also coincided with human migration to North America.
Tim F.
It’s a question for which there isn’t an easy answer. Solar cycles are a very strong candidate, they’re called Milankovitch cycles and there are actually three of them. The Earth’s orbital path cycles between elliptical and circular over the space of roughly 100,000 years, which very likely contributes to the 100,000-year glacial cycle. In the second cycle, the Earth’s axis relative to the sun cycles between more tilt to less tilt and back over roughly 41,000 years. The third cycle, called ‘precession,’ describes whether the northern or southern hemisphere is pointing towards the sun when the Earth’s orbit brings it closest to the sun, which cycles through a period of roughly 23,000 years. You can find a good primer here.
QuickRob
My questions:
If greenhous gas levels have never been so high in the last 650,000 years, BUT THE AVG TEMP HAS BEEN HIGHER MANY TIMES IN EARTHS HISTORY, how does anyone make a demonstrable connection between greenhuse gases and warming from that data?
If anything it seems that this new data helps put the recent accepted view of global warming being a result of human activity into question.
In the past, with less greenhouse gasses, Earth has been warmer. That was cyclical. Why is it wrong to consider this warming as cyclical especially considering the difficulty of accurately knowing the average temperature so long ago?
How are we not confusing correlation with causation? anyone?
vinc
scs, temperature isn’t on the graph… what they have is a temperature proxy. They infer global temperature by the chemical composition of the ice core. I believe what they’re doing is looking at the amount of deuterium (it’s like heavy hydrogen) in the ice. A change in temperature leads to a change in the amount of deuterium. What they’ve graphed there, I think, is the amount of deuterium and not the actual inferred temperature–probably because this paper is aimed at other scientists and not at the public, and the deuterium data is more useful to other scientists.
There’s a time lag. If you’re cold and you put on a jacket, it takes you a while to get warm.
Tim F.
That’s the only part of the graph that’s really obscure. The funny symbol is called del-dueterium, where deuterium is an isotope of hydrogen that’s found in water. The temperature determines the ratio of normal hydrogen to deuterium in water, so measuring that ratio gives you some idea of the temperature.
Assume that 9 parts per thousand (ppt) of deuterium, which are the units on the temperature graph, correspond to one degree celsius in the inverse direction. That means that negative nine ppt equals plus one degree celsius. I count about +50 ppt difference between today and the last glacial temperature minimum, which means that it was about 5.5 degrees celsius colder then.
Tim F.
As vinc pointed out, warming takes time. We’ve only had ridiculous CO2 levels for a few hundred years at most; your average warming period takes one to five thousand years. There is no reason whatsoever to think that nothing will happen just because it hasn’t happened yet.
scs
Okay, thanks that helps out with the graph and solar cycles. As an FYI, I was looking around and saw this article in National Geographic magazine about melting ice. If you follow the link to Greenland, it says this:
Also as an fyi, saw this map on the last ice age in Europe.
BSR
I can’t make any sense out of that graph. I mean, if the earth started 6,000 years ago, where’s all that other data coming from?
My brain hurts. I better ask Pastor Ted….
BIRDZILLA
We had a mini ice age at one time and that was long before we had any industries and cars so what cuased it? it did,nt have anything to do with people burning coal or wood on their cooking fires but is more likly a natural phenomena. And the biggist amount of HOT AIR comes from AL GORE and GREENPEACE
The Disenfranchised Voter
Hey Tim F. Any chance we could get an open thread? I see there is 34 readers on right now and I’m bored, drinking, feel like chatting. I don’t wanna clutter this post up…
It would be much appreciated.
Tim F.
You got it.
The Disenfranchised Voter
You da man, Tim!
Ken Hahn
Let’s see. Greenhouse gasses are the highest they’ve ever been and they are the primary cause of global climatic change. It hasn’t cooked us because these things take time. We only have 1000 to 5000 years before Hudson’s Bay resembles Puerto Rico and Siberia becomes tropical.
So let’s all panic and run around screaming because we’re gonna die within five millenia. Let’s just give up civilization and return to a world that can support maybe a couple of million humans, engaged in hunting and gathering and worshipping Gaia. Let’s ignore that the change so far is so small as to be measurable only by the finest of instruments of the technological society that we are going to abandon.
Okay, let’s be honest. This isn’t about climate, it’s about power. Elitists don’t like that they can’t tell us how to live our lives. Climate is the latest excuse to force the average person to give up freedom for security and liberty for comfort. The earth has enormous self correcting mechanisms. It is not going to melt because of CO2 or other gasses. Changes are slow and we’ll be able to use undreamed of technology before global warming kills one person. If you prefer a comfortable slavery to the discomfort of progress then go live that way. I will never concede the authoritarian climatologists the slightest sliver of my liberty.
Basically it’s all politics.
Jon H
” Elitists don’t like that they can’t tell us how to live our lives.”
You just like to be told what to do by different elitists. The CEOs of the energy companies and US automakers are elitists. The staff of right-wing think tanks are elitists. Right-wing politicians are elitists.
Jon H
“If the earth had no atmosphere at all, it’s average temperature would be about -20 Celsius (about -5 Fahrenheit, or completely unsuitable for complex animals, let alone humans.)”
The ecology around geothermal vents would still be interesting.
Maybe there’d be sentient lichen.
The Disenfranchised Voter
Hear, fuckin, hear!
What a great reply!
CaseyL
50 Degrees Below, Kim Stanley Robinson’s second book in his global climate change trilogy, just came out. He talks a lot about the Younger Dryas. It’s a period of rapid climate change, brought on by a whole bunch of tipping points all tipping at once. “Rapid” meaning 3 years of dramatic climate and weather change, as opposed to centuries or millenia.
What naysayers still think is going to happen is a linear process and uniform warming, and maybe a few “unimportant” coastal areas being permanently inundated. They couldn’t care less about the inundation, and they think it’ll be nifty to not have to scrape their cars in the winter.
It won’t be uniform and it won’t be linear. GCC will sink the Gulfstream, which sends warm ocean water and warm air masses to the North Atlantic, which will affect precipitation as well as temperature. The North Atlantic areas will actually get colder and drier – enough to wreak havoc with agriculture. And the rain that would normally have fallen in that area will fall elsewhere – and not necessarily anyplace where it would do much “good.”
Tim’s already talked about the impact of different types of CO2 on agrable crops. But CO2 isn’t the only gas that GCC will release into the atmosphere. There’s a lot of methane trapped in deep cold water that’ll be released, too; and methane is a far worse greenhouse gas than C02.
These secondary and tertiary factors are what will accelarate GCC.
GCC is a done deal. We should have started drastically reducing greenhouse gases 20 years ago; instead, we went rapidly in the opposite direction. And there is no will in the WH or Congress to address the issue in any meaningful way. The best we can hope for at this point is ameliorating the rate of change, and its duration, and try to head off the more extreme change.
The bad news is, we lack the will to do even that.
The good news is, GCC will drastically reduce the human population in the next 50-100 years. (Sooner, if the worse Younger Dryas scenarios play out.)
So I guess, if I were someone who didn’t care much about humankind, I’d be pushing to ignore GCC altogether, or at least not take it very seriously. I’d be out there reassuring people that GCC is just some leftist eco-terrorist plot; that nothing was going to happen except a few unimportant coastal areas will be inundated and we won’t have to scrape our cars in the winter anymore. I’d talk up the longer growing seasons and not mention what it was we’d actually be growing, or where.
Tim F.
Yup, nonlinear threshold effects are just on top of my list of common climate misconceptions.
Clathrates scare the bejeesus out of me. We have this spectacular positive feedback loop sitting down there just waiting to be activated. If it does, then Dryas doesn’t sound unrealistic at all.
Ken Hahn
Jon H.
Perhaps the officials of think tanks and energy companies are elitists. So far, I’m not aware they are engaged in any legal process to force me to buy their products ( or their ideas ). The left cannot compete in the marketplace of ideas and so uses the government to compel people to behave as they choose. I ride a bus to work and no oil company agent tries to fine or jail me for my choice. Should the left elitists gain power, they would do so with enthusiasm.
I’m sure Tim really believes the charts he linked are evidence that unless I’m forced to conserve we’ll be roasted shortly. I disagree. He has every right to try to convince me, as I do to convince him. Neither of us has the right to force to other to behave other than as we wish without direct evidence of harm. A climate change over 5000 years is not good enough.
The left elite were horrified when the U.S. refused to ratify the Kyoto Treaty. We are blamed for the greenhouse gas effects that Kyoto seeks to address. Yet every honest person concedes Kyoto would be a small stumbling first step and would do nothing without more severe regulations following one upon another. The Europeans are finding the Kyoto goals unreachable and even very green New Zealand is discovering that ratification is going to cost them enough to wreak their economy. The only way to cut greenhouse gasses enough for the elites is to dismantle industrial society.
The current proposals to fix greenhouse gas emissions are essentially cutting off an arm to prevent a rash on the hand from spreading. The only way this can be sold is by panic. I see no reason to trust the panicmongers.
Tim F.
Ken,
You misunderstand how government works. The oil companies force government. Government forces you. To pretend that they don’t employ any coercion on the American people is simply ridiculous.
Frank
An example might be the way the Oil and the Car companies had almost all the light rail in the country torn up. San Fransisco is the only town left with electric trollies. Maybe you don’t see the interstate highway system as a gigantic subsidy for oil, gas, and auto co.s, but many people look at it that way.
TTT
Ken:
“So let’s all panic and run around screaming because we’re gonna die within five millenia.”
Five millennia? I thought Saddam was a threat to the U.S. already!
Wait, sorry, wrong elitist panic-mongering.
CaseyL
Oh, Pish and Tosh, TTT.
The leftist pinko eco-nuts ranting about GCC are asking that we develop different technologies to power our automobiles and industry, thus attacking the very foundations of American Liberty – all that, in order to avoid some trifling change in global climate that won’t mean much beyond the loss of a few trivial biomes and the dispossession of a mere few hundred million people, at some impossibly distant 40 years’ time.
The neo-theo-paleo-cons who ranted about Saddam merely demanded that we give up our sons and daughters, our husbands and wives, our civil liberties and public wealth, our national reputation and values – in order to power Maximus Leader’s fantasies of messianic imperialism right this hot second.
Surely you can see the difference between the two cases.
scs
First of all, automobiles only account for less than 42% of greenhouse gasses. Even if we double car milegage, it will make only 20% difference. While that may help for now, in the long run it will grow again as the population grows. It ain’t no holy grail.
scs
Second of all, if you look at that graph at the top, you can see that we are soon due for a nice long ice age. I say start buying SUV’s now and start driving for no reason, to help give the earth a nice little bit of carbon insulation.
CaseyL
Absolutely, scs. We should totally do that. Anything to hasten the day and all that…
Every so often, I regret that I never had kids. Then I see comments like yours and Ken’s and realize I made the right choice. I have no hostages to fortune.
gt
I diina thin’ you’re paranoid delusions really help any..
If you think that the Oil companies run the government is some way you don’t know jack about gas blend regulations, NIMBY prevention of new refineries, Hell how exacly haven’t they gotten the ANWar issue in their favor if they actually run the government..
It is to laugh ^_^
gt
On another note, unless i’m reading that graph wrong (and I mght be) Is the temperature spiking before the carbon and methane really take off or what?
Tim F.
Well now, if I didn’t know better I’d say that we have here a reductio ad absurdum fallacy. Tell me that I’m wrong.
scs
.Hey man, can’t you read graphs? Look at the bottom purple line. What happens after a big temperature spike every 100,000 years or so. A nice 100,000 year ice age. I didn’t make it up. Let’s hope we don’t go back to the named ‘SnowBall Earth’ conditions that I heard happened millions of years ago.
GT
You know I’d have asked you the same thing almost- but no..
http://en.wikipedia.org/wiki/Reductio_ad_absurdum
Nope, actually I’m doing the opposite. I’m assuming less than you’re statment. I’m not asterting that the Oil companies coerce the populace via the government by coercing the aformentioned government. I’m asserting that they can;t even coerce the government to get hings tehy want diesctly much less coerce the government to coerce people for them..
I’d say you might be guilty of Correlation implies causation
http://en.wikipedia.org/wiki/Correlation_implies_causation_%28logical_fallacy%29
Tim F.
GT, you argued that oil companies don’t have absolute power over government. That, of course, is not what I argued. So you misrepresented my point and then argued against the misrepresentation. If you don’t like reductio ad absurdum, which it was, then you can have a straw man.
Tim F.
Then you are wrong. Demonstrating that they don’t get everything they want fails to prove that they get nothing that they want.
Faux News
I thought Darrell had already established that the Earth is only 6,000 years old and mankind lived with the dinosaurs.
scs
Okay, since we have no new postings in the last day, I will ask this. Does anyone have a theory why the earth didn’t have the usual temperature spike, or a flatter spike in the last 10,000 years, according to the graph above? Could it be that the fires and agriculture that humans have caused in the last 10,000 years (which I have read before can cause some pretty signicant greenhouse gasses) created some global warming already? Maybe this mini global warming caused by primitive humans is the reason we had the stable temperatures in the last 10,000 years to begin with, which Tim speculates is responsible for our advancement. So I’m doing a little cart and horse switching here. Just a thought.
Frank
scs- You might be right about that. You might also see if you can track down a map showing the expansion of deserts since the dawn of agriculture. I once saw a picture of what the fertile crescent looked like 20,000 years ago, next to one of what it looks like now. I’d be interested if you can find the linkage.
jack
Here is the problem in a nutshell. The global warming believers want drastic action taken based on no irrefutable evidence. Various aspects of the socialist left have clambered on board the global warming theory to propose draconian ‘remedies’ that seem aimed more at imposing socialistic eco-controls over business as a pre-cursor to their eternally popular revolution.
Needless to say, the Right finds this whole thing abhorrent.
But for their part, they do offer an alternative course–further study of the data and a free-market approach to solving the problem.
Needless to say, the left finds this abhorrent.
Trapped in the middle are a handful of scientists who have no political ax to grind, who want to find out what’s going on, if it’s dangerous, and what we can do about it.
Absent the politics, and this issue might be getting the research and recognition that it deserves. With the politics, we get shaded studies, biased data and endless reports of impending doom–and anti-doom responses. Which serves no useful purpose.
We are arguing loudly about whether we should arm ourselves before we go investigate the sound we heard downstairs.
Frank
jack- Except that the overwhelming majority of scientists believe that climate change is real. That is they can hear the intruder triping over furniture and cussing.
Also most of those who believe in climate change aren’t calling for drastic remedies. Heck if we just did away with the SUV tax loophole and gave a similar breaks to people buying hybrids, we would have made a huge dent in the problem right away.
I’d be up for replacing our coal-burning powerplants with nuclear ones, but unfortunately not everyone agrees.
jack
Frank, every scientist worth the name believes that climate change is real–it’s a nothing statement. The climate changes. If you’re too stupid to know this you probably aren’t out of grammar school.
Likewise statements that revolve around humans having an impact on the planet. D’uh.
Scientists are divided fairly evenly over the question of whether WE’VE caused climate change–and when you eliminate ALL scientists with political ties the much smaller group left isn’t ‘divided’ at all–they’re also not on either side of the debate. They want to test, and experiment, and learn.
And learning is the key because we are not yet able to handle–even with computers–all the variables involved in completely understanding our climate.
I recently pointed out, in another GW thread that Tim posted that the people making the charge–the Gulf stream stopping will cause cooling–proffessed some constrenation that the facts of temperature readings–a.05C rise in average temperature–did not bear out their modelled conclusion.
We don’t know enough to make the broad predictions that are being made. And there is far too much political influence in the mix.
Frank
jack- Scientists allways want to know more, and we will never know enough to completely explain or predict the atmosphere. We do know beyond any question that carbon dioxide is at an unusual high right now, and that we can take some fairly low cost measures to reduce the amount we contribute to this.
Of course there is politics involved. Its a political question: what collective action are we willing to take to reduce the amount of climate change we have to deal with?
The problem is the right feels compelled to lie about this stuff, not that politics are involved.
vinc
They’re not at all evenly divided. There’s a very large majority who believe that the climate is changing and that humans are causing a major part of that change. The debates are over how much and how fast and what should be done.
I don’t think it’s possible to read Science or Nature regularly and not be convinced of that. Unfortunately, 99% of the people who have an opinion on this subject have never come closer to a scientific journal than Popular Mechanics, and yet somehow they pretend they know what scientists think.
This is seriously something where you don’t have to accept what the politicians and talking heads say. You can find the truth! Go to any real journal, search for “global warming” and read the abstract from a few dozen search results. There will be a lot you don’t understand, but I think you’ll at least pick up that what I’m saying about the shape of the debate. Yes, it’s work, but a lot less work than debating for hours.
Here, I’ll do the search for you:
Science Magazine
If you don’t like that, do it on the journal of your choice.
I think (I hope!) that article abstracts (summaries) are available to nonsubscribers.
And the strawman of econommic doom really annoys me. What do those “authoritarian climatologists” want us to do? They want us subsidize fuel-efficient cars and penalize inefficient ones, invest in public transit, stop subsidizing nonrenewable energy so heavily, increase subsidies and research in renewable energy sources, slow the rate at which we deforest the world, and so on. The horror! All of these would be totally defensible policies even if climate was a nonissue.
vinc
You’ve reached the limits of my knowledge there. My opinion would be that you’re trying to extract too much information from that data–we only know a couple peaks in that much detail, so we can’t be certain of the pattern yet. But I don’t really know. I’d be pretty sure that pre-industrial revolution activities weren’t enough to have a noticeable effect on climate but I’m not certain. We’ve done some serious desertification over the past 6000 years.
(I do research, but in solid-state physics which aside from some basic concepts is completely unrelated to climate, so while I get more exposure to this debate than your typical blogger I’m certainly not an authoritative source.)
John
Amazing that in all of this thread, only one person pickes up on the fact that in the chart the tempature spike comes first and the increase in greenhouse gasses comes afterward. So then according to one logical train of thought, higher greenhouse gasses are a consequence of and not a cause of higher tempatures.
Actually, there’s a good discussion about the entire article over at
John
The site is realclimate.org
TallDave
Ice Ages are nice and stable. Warmth is far more important than stability.
There were several Ice Ages in that graph range. Given that, I’m not sure how anyone can argue we want to stay in that range.
Someone asked about the temperature-gas disparity, where the gas levels seem to lag the temp rises. From what Ive read recently, this has apparently been explained as a problem with how the ice cores are interpreted, and upon closer analysis tend to disappear. So greenhouse gasses do cause GW, and we are certainly affecting greenhouses gasses, so there is some amount of anthropogenic GW. How much, and whether that effect is a net positive or negative for humanity is still an open question.
There is still very little consensus on how those precipitous CO2 drops occur. I think a lot more research needs to be done before we abandon fossil fuels or tax them into recession-inducing prices in the face of climatic doomsaying.
I do think it makes sense to incentivize nuclear, alternative, and hybrid technologies, and not just for reasons related to climate. If technological progress continues to accelerate, this could be a non-issue in 20-30 years as renewable nonpolluting sources of energy become available. For instance, if we get a space elevator up and running, orbital solar energy suddenly becomes far more economical.
Unless…
John
Where have you read that? So now we are to believe that the scientists who did the research and wrote the report and got it published got the basic point of which came first the greenhouse gasses or the tempature spike wrong! And now because the answer didn’t fit the GW caused by man theory, it’s been reworked to get it “right!”
Ken Hahn
Tim,
I don’t think I misundrstand. Please give me something other than a “known fact” to back up how the oil companies are forcing the government to force me to do anything. I am forced to buy a different blend of fuel from the people in the next state. But that’s because enviromentalists have determined that oil companies must mix it differently here in California than is required in Arizona. Were an oil company to try to build a refinery here, your green friends would tie them up in court with enviromental impact reports for decades after which a liberal judge would make them start the process over. So I get fuel from an inefficient refinery that can’t be replaced because of greens and NIMBYites.
I do not know you and I would not accuse you of being unaware of the actions and motivations of government. But I am aware of how government works. I have been watching it for a long time. I am prepared to be persuaded that I am wrong, but you’ll forgive me if I don’t take it on your authority. I have no desire to compel you to do anything the way I chose to do it, but you would be happily satisfied if I were forced to live “green”.
To those of you who worship science, I’d offer a caution. Nearly everything I studied about science less than a half century ago has been proved wrong or distorted. There is a great deal we do not know. Most of all we know a lot that is going to be proven incorrect as better measurements and instruments become available. Science is not about answers, it is about understanding the questions. The more we accept “known facts” the less science we do.
TallDave
John,
If you google you can probably find it. The re-interpretation was apparently widely accepted on technical grounds. IIRC, had to do with the fact the stuff they used to measure the temperature would have been deposited later than the stuff they used to measure the gasses.
jack
vinc, I read every single abstract offered in your Science link. What I got was uncertainty, refutation of popular GW advocates ideas, WAY too many political reports and an overall affirmation of my notion that scientists without political baggage are in my camp–the one that suggests that we need more research.
I confess to finding it odd that the call for more research it met with such vehemence. What is wrong with knowing what and why we’re doing something before doing it?
And the–and I use the term with all intent–stupid leftist notion that a lack of belief in their solutions to the global warming issue includes a hostility towards renewable fuels, better fuel efficiencies, alternate energy sources, etc. I want cheap clean power as much–or perhaps more than your average eco-nut. Most likely more because the eco-movement has a wide luddite streak.
I just happen to think that private interests will do far better than governmental agencies, complete with their bloated bureacracies, at finding the solutions we need.
Frank
The problem is the right feels compelled to lie about this stuff, not that politics are involved.
December 5th, 2005 at 6:09 pm
jack
Ah, thanks Frank. Thanks for that unbiased, incisive and inane comment.
Do you not think the the right says the same about the left?
And worse, do you not understand that this type of thing is poitics at it’s most stupid?
vinc
You read all 6355 abstracts? I assume you meant you read the first ten. I don’t think that’s enough for a good sample, but anyway…
Of those, I’d say that
#1 is about *abrupt* climate change, and doesn’t say much about climate change generally, other than there exists a risk of a large change due to human forcing
#2 is about climate feedback mechanisms and doesn’t address CO2
#3 is about alternative energy and ways to reduce CO2
#4 is about an event 10,000 years ago
#5 is about atmospheric particulates. “Carbon dioxide and other gases are well known to warm Earth’s atmosphere.” It then goes on to discuss other particulates.
#6 is about modelling earth’s temperature based on emissions, and predicts more warming in the future
#7 argues that “climate stablization will require a massive transition to CO2 emission-free energy technologies
#8 estimates the amount of warming over the next century, based on expected emissions and a couple other factors, and finds it to be 1.7-4.9 C with 90% probability
#9 says that warming from 1925-1944 may have been due to “a combination of human induced radiative forcing” (which means CO2) and hitting a high point in an atmospheric cycle.
#10 argues that if global warming occurs, it is unlikely to lead to an ice age.
I’d say 1, 2, 4, and 10 don’t really say anything about whether human activities now are causing warming.
All the rest, I think, at least implicitly accept that warming is occurring and due to humans.
I see nothing that even suggests that there is a debate about whether current warming is due to human emissions. Everything either accepts that and argues about the consequences, or doesn’t address it.
Which one of these would you disagree with?
Anyone else who’s curious can check my interpretations here.
vinc
Also, no one’s hostile to doing more research. But you can *always* do more research. There is never a point at which a system will be fully understood. At some point you have to act.
Economists don’t fully understand what effects a tax cut might have on the economy. But that doesn’t mean that they shouldn’t advocate cutting taxes in response to macroeconomic shocks.
The current situation is a classic tragedy of the commons situation, right out of an econ textbook.
Frank
Vinc- Great post! I just didn’t have the patience to deal with jack’s mendacity any more. Thanks