Lars, if you'd use more than sentence fragments to get your points across, I'd understand them better and give you clearer answers.
You seem to be misreading the curves or something.
Looking at MY chart (thank you for mentioning that, I am rather pleased with it), according to the red Antarctic curve, at 1050 there was a reduction in sunspots--from a peak (950) to a valley (1050) to another rise starting at 1100 AD.
Now, looking at the blue Moberg et al 2005 temp curve, what we see is a peak in temperature at 950, followed by a drop in temps (1050) that corresponds pretty well with the dip in sunspot activity, followed by another rise at 1100 AD.
Where is the problem? Bearing in mind that we're comparing two different processes (sunspot activity vs. global temperatures), defined by different sets of data (ice core Beryllium-10 concentration vs. tree-ring data and low-resolution proxies), that happened at different places around the globe, I think its striking how well the curves track.
So why was the GW deniers favourite Medieval Warming Period during a minimum of sun-spot activity? Ooopsy.
Not really. Using the red Antarctic curve for comparison (neither the Greenland or GRL curves go back far enough), the sunspot activity does show an MWP, it just starts a little before the MWP begins (using the Moberg curve for comparison) at about 950, dips for a bit at 1050 (notice how the Moberg curve's temps also dip), and picks up again at 1100 or thereabouts. Pretty close match, considering the MWP is supposed to have happened between 800-1300 AD.
N.B.: Don't use the Mann et al 1999 curve for comparison, it doesn't work as well because his MBH team smoothed out the Medieval Warm Period and Little Ice Age. But that's another story...
First let me say that I've really enjoyed this, thanks! We seem to have mined out the subject, so I'll reply to this posting and give you the last word, if you want it.
The effect is minimal compared to the total contribution of water vapor, but compared to "able to change the temperature by a few degrees", the increases in CO2 concentration from pre-industrial times is not minimal.
That's what I disagree with. CO2 levels and global temps have never tracked over 600 million years. Except for the theory that falling CO2 levels caused the Ordovician ice age and extinction -- an interesting theory, but not a likely as the Gondwana freezover theory--there's no other instance where CO2 drove global temps.
First, a 20x increase in CO2 concentration is not as big as it sounds, because the climate sensitivity is logarithmic in CO2 concentration; it doesn't imply, for instance, a 20x increase in temperature. It is, however, still big compared to anthropogenic contributions. If you're talking about a period when global temperatures were comparable to today's values, like the Ordovician, please remember that was an ice age.
I agree that a 20X increase in CO2 isn't as big as it sound (I'm arguing that it has a minimal effect even at that level), but if a 30% increase is enough to raise temps up to 4.5 degrees C in a short time, according to the IPCC, why wouldn't a 20X increase increase temps by an equivalent amount? I was not aware that climate sensitivity is logarithmic where CO2 is concerned (probably because of it only being present in trace amounts in the atmosphere). The fact seems to support my argument more than yours, because, if it's logarithmic, maybe a 30% increase in CO2 is completely negligible and you have to get increases of 2000X (guessing again) or more to see a difference.
The Earth's albedo was significantly than it is now, implying less retention of the Sun's heat. Other greenhouse gases, many of which (as you pointed out) are more efficient at trapping heat, may have been less prevalent. There could have been many more aerosols in the atmosphere from volcanism. There are all kinds of effects which can contribute majorly to cooling. But one of the best theories is the one you dismissed: the ice age actually occurred when CO2 levels dropped, setting off positive cooling feedbacks.
The Earth's albedo has changed radically over millions of years: Ice Age, the albedo's high, Age of Dinosaurs, not so much. The albedo changes, CO2 levels rise and fall, yet global temps remain stable. I think much of the increase in CO2 over the millennia is caused by the huge increase in lifeforms. Our current environment is almost empty of life compared to the ecosystems of the Paleozoic and Mesozoic periods. If organisms account for 38% of the CO2 in the air today, they must have been blowing out hundreds or thousands of times more of it back then.
My understanding from discussing GW with others is that CO2 from volcanoes has little impact on the climate because it can't get high enough into the atmosphere to make changes. As for other aerosols, over a half billion years, don't you think we'd have several cases of CO2-driven warming? As I've mentioned before, that Appalachian Mountains theory flies in the fact of other theories that have pretty good evidence backing them up. It reminds me of the worries that increasing CO2 would flood the the North Atlantic, disrupting the oceanic "conveyor belt" and sending us into a snap ice age (like in that documentary "The Day After Tomorrow"). Turns out that, while they've got a good theory, it would take orders of magnitude more fresh water to have that effect than can possibly be generated by AGW. Similarly, I'm sure that eroding down the Appalachians could cause local chemical effects that might lower local CO2 levels, but it wouldn't have a global impact.
So it comes back to the beginning of this discussion. I think there are factors causing global w
You claimed that the climate is insensitive to CO2 concentration, which is not the case. I'm sorry, you cannot on the one hand claim that the climate is insensitive to changes in CO2, and then claim that CO2 does impact the global climate.
Of course I can, CO2 is a greenhouse gas, one of many trace greenhouse gases in the atmosphere. It effects the climate, but that effect is minimal. Mess with the concentration of water vapor in the atmosphere, then you have a major effect on climate.
That argument, as well as all of the other arguments you are making here, are predicated on the same mistake, which is that you cannot infer absolute temperatures from absolute CO2 concentrations unless you know a great deal about all the other climate factors. We know a lot about them today, but not much about them hundreds of millions of years ago. You simply cannot conclude that X amount of CO2 means Y temperature. You can sort of conclude that dX change in CO2 means dY change in temperature, but even then that's only possible when you have a handle on the changes in all of the other forcings.
Please explain what other forcings might possibly counteract high global temps being caused by CO2 levels 17.5 times higher than today's levels.
Thanks for pointing out the references, I'll look 'em up.
I have not claimed that CO2 emissions are the only factor that influences global temperature, nor have I claimed that the Sun does not affect global temperature. What I claimed is that solar variations cannot account for the majority of the recent (last 50+ years) warming.
And I have not claimed that CO2 doesn't impact global temps, it's just that historically, the record shows that global temps do their own thing, regardless of what the CO2 levels are doing. Unless there was a cosmic changing of conditions that obtained 600 million years ago, we're still dealing with the same major players: Earth & Sun. When CO2 dropped from 7000 ppm to 400 ppm while average temps remained within a 10-degree C band, that's such an enormous change in CO2 that there should have been a parallel change in temps. Of course, since the IPCC is claiming a 30% increase in CO2 will cause a 2 to 4.5 degrees C jump in temps, when CO2 levels were at 7000 ppm, global temps must have been around (guessing) 500 degrees C, right? Obviously they were not. Even though we're dealing with paleo climate, we have enough data that we can be sure the Earth's temp wasn't hotter than a volcano.
It is impossible to predict absolute global temperatures from absolute CO2 levels alone; you have to know what all the other forcings are doing; paleo data that far back doesn't tell you anything about the climate sensitivity. You can do better predicting changes in temperature from changes in CO2 levels, but even that is not very useful given the sparsity of the data on million-year timescales. Changes in CO2 levels and changes in temperatures do correlate well in the finer-grained data over the last few hundred thousand years (e.g. the Vostok ice cores). And CO2 is in fact implicated even in far-past climate changes, such as the Ordovician cool period you mention
I read the article you cited on the erosion of the Appalachian mountains sucking up all the CO2 and thereby causing the Ordovician ice age, I just don't agree with it. I prefer this theory:
The Ordovician mass extinction has been theorized by paleontologists to be the result of a single event; the glaciation of the continent Gondwana at the end of the period. Evidence for this glaciation event is provided by glacial deposits discovered by geologists in the Saharan Desert. By integrating rock magnetism evidence and the glacial deposit data, paleontologists have proposed a cause for this glaciation. When Gondwana passed over the north pole in the Ordovician, global climatic cooling occured to such a degree that there was global large-scale continental resulting in widespread glaciation. This glaciation event also caused a lowering of sea level worldwide as large amounts of water became tied up in ice sheets. A combination of this lowering of sea-level, reducing ecospace on continental shelves, in conjunction with the cooling caused by the glaciation itself are likely driving agents for the Ordovician mass extinction.
It jives much better with what we know about atmospheric CO2: 38% is caused by respiration, 57% by the oceans. Freezing the water would have done away with ocean generated CO2 and freezing the planet in general would have killed off the organisms whose respiration provided the balance.
Temps drop, things freeze, CO2 levels drop. Not the other way around.
Your point?
As for my bringing up the extinction periods, yeah it was off topic, I just find it fascinating that the conditions we live in, given the history of the planet, should be considered dire, yet we act as though that's the natural state of things. Anyway, I shouldn't have mentioned it.
What "runaway greenhouse effects" do you believe current models lead us to expect?
You know, their models say that an increase in CO2 by 30% causes temps to increase by 4 degrees. So when they were 7000 ppm, temps should have been some outrageously high reading, but they weren't. That runaway effect that didn't happen. Because the climate isn't sensitive to changes in CO2.
I was already familiar with the Wikipedia cite, what other papers did you refer to?
You say the CO2 emissions correlate with global temp curves, did they cause the Medieval Warming Period or Holocene?
No.
Other than solar activity, the only explanation for the extraordinary Holocene warming is a recent (1999) theory that the Earth's tilt may have changed for a couple thousand years. That theory is based on a model, there's no evidence as of yet. But it could be that the change in tilt and unusual sunspot activity caused the warming.
So maybe it's manmade CO2 and sunspots together causing the current warm spell?? Possibly, except that the Earth's history shows the global climate has little sensitivity to CO2 levels. For example, over the last 600 million years:
- CO2 levels have dropped from 7000 ppm to approx 400 ppm
- Average global temps have remained steadily within a 72F (22C) to 54F (12C) range while CO2 levels have plunged to current levels
These fact alone show that the Earth's climate is not as sensitive to changes in CO2 levels as the models indicate
Finally, there have only been three periods during which temps have been as low as they are today, and the other two took place during mass extinctions (Ordovician and Permian). Also, the Permian extinction period is the only other time when CO2 levels have been as low. Just another coincidence? Or proof that we're in an unstable period of cooling and the Earth's climate is eventually going to get warmer no matter what we do.
So there you have it: wide swings in CO2 levels have occurred at the same time temps have remained relatively stable; certainly there haven't been runaway greenhouse effects that the current models would lead us to expect. In short, I question your science.
Yes, that's your problem. You have to do that, because when you do, you find out that the solar output isn't actually changing enough to account for the observed temperature changes. Your analysis is only semi-numerate; you cannot ignore the actual quantity of solar output.
Look, you have to explain more clearly because it's not easy to understand your point.
For argument's sake, let's say sunspots are twice as numerous as they've been in a millennium. The stock market's at an all time high too, does that mean it's because of sunspots? Hardly likely, because there's no connection we're aware of between stock prices and sunspots.
Ah, but global temps are also shooting up at a very fast rate, in fact the rate of increase strongly resembles the rate of increase in sunspots. Coincidence? Possibly. But as the Sun does control our climate, it's much more likely that the activity causing increased sunspots is also causing increased temps on Earth.
Especially when past history shows two other warm periods that also happened at periods of unusual solar activity.
Your argument breaks down when you try to turn "sunspot number" curves into "temperature anomaly" curves.
I'm not turning ""sunspot number" curves into "temperature anomaly" curves", I'm comparing anomalous behavior in sunspots over a period of time with global temps. When you see the following:
- Temps are higher than they've been since the Medieval Warming period, and before that the Holocene period.
- Sunspot activity is higher than at any time since the Holocene period
- Sunspot reconstruction curves track pretty well with global temps (at least as well as global temps track with each other) and the curves shoot up in the same proportion as the global temp curves do.
It's proper to infer that sunspots are responsible for the warming we're experiencing.
We've currently just passed through a solar minimum (in the 11-year cycle), yet we are still setting record highs.
Take a close look at this black GRL line in these curves, it does shows a drop in activity around 1950 (but even the low was still much higher than the average over the last 1000 years) and it's since bounced back up again.
Did you look at the curves or not? The current sunspot activity hasn't been at this high a level for 8,000 years or since the Holocene period. During that period:
The Holocene climatic optimum was a period of warming in which the global climate became 0.5-2C warmer than today. However, the warming was probably not uniform across the world. It began roughly 9,000 years ago and ended about 5,000 years ago, when the earliest human civilizations in Asia and Africa were flourishing. This period of warmth ended with a cooler period with minor glaciation, which continued until about 2,000 years ago. At that time, the climate was not unlike today's, but there was a slightly warmer period from the 10th-14th centuries known as the Medieval Warm Period. This was followed by the Little Ice Age, from the 13th or 14th century to the mid 19th century, which was a period of significant cooling, though not as severe as previous periods during the Holocene.
Combination of these newly calculated water ages and previously reported noble gas temperatures reveals new aspects of late Pleistocene and Holocene climate in southwestern Texas, in particular, an abrupt late Holocene temperature increase previously unidentified through 14C dating. Temperature increased by up to 3.4 C in the first half of the last millennium and by 1.5 C between 5.6 and 3.7 kyrs BP.
Abstract from "Noble Gas Thermometry and Hydrologic Ages: Evidence for Late Holocene Warming in Southwest Texas"
And other recent research is finding that sunspots were largely responsible for the Holocene warming:
Glacier fluctuations of the last 10,000 years have been reconstructed in Garibaldi Provincial Park in the southern Coast Mountains, British Columbia, from historical documents, dendrochronologic and lichenometric dating of moraines, and radiocarbon dating of fossil wood in glacier forefields. Six major periods of glacier advance are recognized: 7700-7300, 6400-5100, 4300, 4100-2900, 1600-1100 14C years BP, and the last millennium. Evidence for each of these six periods was found in the forefield of Sphinx Glacier, the only glacier in western North America with so complete a record. Evidence for each period, except the 4300 14C years BP event, was found at two or more sites, showing the regional significance of the advances. The data demonstrate that the LittleIce Age in Garibaldi Park began as early as AD 1000. The earliest maximum was achieved in the 12th century, followed by recession until sometime in the 14th century. Several glaciers advanced into forests in the 14th century, culminating with the construction of moraines in the late 17th, early 18th, 19th, and early 20th centuries. Helm Glacier provides a near complete record of fluctuations since the 14th century. Glaciers receded between the 1930s and 1960s at average annual rates of about 30 m. Between the 1960s and 1980s,glaciers advanced up to 300 m, but since then they have receded at annual rates of 5-10 m. Ice cover has decreased by about 240 km since the Little Ice Age maximum, with most of this loss occurring after the 1920s. Some small glaciers in the park have already vanished, and more are likely to disappear if the current trend continues. The record from Garibaldi Park is broadly synchronous with records of glaciers throughout the world, suggesting a global forcing mechanism. Hemispheric temperature change can explain glacier behaviour during the last millennium. The Garibaldi record shows a relation to reconstructed Holocene sunspot activity, suggesting that changes in solar activity probably play an important role in global climate change.
Take a look at this graph. There are two set of curves, one comparing the Mann hockey stick to curves showing sunspot activity. The other compares the Moberg 2005 curve to the same sunspot curves.
Here's what I find interesting:
- The Moberg curve (blue curve) follows the Antarctic curve (red) pretty closely, but it tracks almost exactly the same shape as the Greenland curve (green) when it sweeps up in a steep curve in the 20th century.
- The hockey stick curve (orange curve) doesn't do as good a job of tracking with the sunspot curves, in fact it looks like it averaged out the highs and lows (read "MWP" and "LIA") to come up with a relatively smooth shape, but even so, it's still a fair match to the sunspots, especially when it sweeps upward in the 20th Cent.
This can't be coincidental, can it? The obvious conclusion is that the global temps are heavily influenced by sunspot activity. If mankind's pouring of CO2 into the atmosphere was a major influence, the curves wouldn't track together so closely (i.e., the steep upswing would be much greater for the Moberg and Mann temp curves than the sunspots), but that's not the case.
FYI: The sunspot reconstructions I took from Usoskin's millennium-scale sunspot number reconstruction published in the November 2003 issue of Physical Review Letters. There's more current research that was just released, but I can't find the link I had to the PDF. The black GRL curve is from that more recent paper and you can see that it matches the others pretty well.
If the relationships I've drawn are correct, doesn't this strongly imply that the Sun is causing this warming trend?
If you don't think the sunspot curves match closely, it may help to see how poorly the various global temp curves match with each other. Take a look at this Wikipedia graphic combining the global temperature reconstructions from the major players. Looks pretty random to me. The only thing that's given them any credibility is that they all swoop up in the 20th century like they're heading for the moon. And so do the Greenland and GRL sunspot number curves.
Based on that, take another look at the SN curves and then at this one where the curves are overlaid on the Wikipedia graphic.
I'd say the SN curves track better with the global temp reconstructions than many of the wilder global temp curves do. Yet all those curves have been cited by "warmists" as being equally valid (because of that lovely swoop!).
Potentially much more severe was the one that occurred at the Enrico Fermi fast breeder reactor in Michigan, U.S.. In October 1966, while operating at about a sixth of full power, the reactor suffered a partial meltdown resulting in radioactive release into the reactor building.
Pardon my... tone. A chain reaction of nuclear explosions? Do you have ANY idea about the subject you're speaking on? It was a meltdown event in a reactor, not a bomb. In 1966
The fast neutron plutonium breeder reactor has nuclear explosion potentials...The stability of the fast breeder reactor requires that the geometric configuration of the reactor core of fuel rods remains undisturbed! If the reactor should lose its flow of liquid sodium "coolant", and the reactor emergency shutdown system should fail to operate properly, a nuclear excursion would be triggered in about a second (!), causing melting and an explosive vaporization of fuel material. The internal explosion in the reactor core can then compact fuel material to produce a more powerful secondary nuclear excursion the whole process happening in a second or two, ending in a catastrophic nuclear explosion. There are no mathematical limits of the nuclear explosion potential. Even atomic bomb size explosion potentials have been calculated.
In the year 1966 the Enrico Fermi fast neutron, plutonium breeder reactor, located near Detroit, Michigan, suffered a mishap in which the flow of liquid sodium "coolant" into two of about 200 fuel modules was suddenly blocked. After a delay, the reactor fission power level began a spontaneous rise due to melting and movement of fuel material in the two modules. The reactor was then quickly, but manually, shut down. Had the shutdown been delayed a second or so, a potential nuclear explosion could have occurred. The engineers took months carefully probing the damaged reactor core, in order to try to determine the state of the fuel, fearing always that the probing could jar the core material, and thereby cause a collapse of some fuel that could trigger a nuclear excursion and explosion. The Fermi reactor was subsequently closed down.
"Going with breeder reactors and other more efficient designs would be good too."
Probably, but the closest we've come to a nasty meltdown/nuclear explosion was when the Enrico FermI fast breeder reactor near Detroit, MI lost coolant because a piece of metal blocked the liquid sodium coolant nozzles. They shut that puppy down just in time--if they'd been a few seconds slower, a chain reaction of nuclear explosions could have caused plutonium in the core to be blasted skyward. The last I read, less that a tenth the size of a grain of sand is more than enough plutonium to kill you, so such an explosion at the Fermi plant could have affected millions.
I like water-cooled nukes; there's more waste to deal with, but they're much safer than the breeders.
Dude, you've got to unbunch your undies over global warming. The Earth's temp doesn't rise when you run your mower or have a barbeque. The worst that could possibly happen is we get a few degrees warmer (woohoo!), the ocean a little deeper, and we could finally stop worrying about those pesky ice ages every few millenia.
At its worst, when CO2 levels were some 20 times higher than today, average temps were 22 deg C (74 deg F). Plus temps remained that high for millions of years after CO2 levels dropped to near current levels, so it's not the highly sensitive feedback system GW proponents generally claim. Warmer than we're used to, but there's always A/C! Because face it, we're not causing this warming spelll, it's been in the cards for a while now and there's nothing we can do to stop it.
As for the ocean's getting deeper, do you realize that if we could make a law forbidding people living closer than 20 miles to a shoreline, we'd save hundreds of thousands of lives today! Take the step of moving people from the vulnerable shorelines and you take away the biggest impact from GW.
Anyway...seriously, the amount of diesel fumes would be trivial in comparison to the amount of fresh water delivered. Plus we could develop nuclear tugs! It's all good.
What's to be excited about lately in space exploration? Another photo of Martian desert that looks like Barstow? (h/t Dennis Miller) When I grew up reading Heinlein and Niven, there might dragons on Venus, dying civilizations on Mars...interesting stuff.
Instead we get scenic photos of Jupiter and Saturn (thanks!) and daily weather reports on Mars. Everywhere we look it's all negatives: sterile, too hot, too cold, air too thin or too thick, gravity too heavy, etc. Sheesh, thermal vents on the ocean floor are more interesting and alien than anything we're likely to see in this solar system!
And Hubble still hasn't detected one Dyson sphere or Ringworld!
I can't get excited by shuttle missions because they're like bus trips: carry cargo up, maybe fix a satellite, fly back down. Other than the spectacular liftoffs and dangerous environment, it's somewhat like watching a FedEx jet do its job day after day.
Whereas with my iPod, I can close my eyes and imagine while listening to audiobooks of Heinlein, "Doc" Smith, and Brin.
Advantage: iPod
What happens when a vehicle with a drunk driver collides with your vehicle? SUV vs. car: people in car survive if they are properly restrained. SUV vs. bike, even with proper helmets: Don't even go there.
SUV vs. car: people in car survive if they are properly restrained
What if a ninja is driving the car and Aquaman is behind the wheel of the SUV, who survives then?
Applause! Anonymous Coward. Such a glittering example of open-minded discussion.
"What a load of crap. Why are you making such a generalization?"
Because I'm responding in kind to someone who painted with an equally broad brush. If you had posted with a real name, we could have carried on a conversation of specifics, but you chose instead to be an Anonymous Coward.
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Lars, if you'd use more than sentence fragments to get your points across, I'd understand them better and give you clearer answers.
You seem to be misreading the curves or something.
Looking at MY chart (thank you for mentioning that, I am rather pleased with it), according to the red Antarctic curve, at 1050 there was a reduction in sunspots--from a peak (950) to a valley (1050) to another rise starting at 1100 AD.
Now, looking at the blue Moberg et al 2005 temp curve, what we see is a peak in temperature at 950, followed by a drop in temps (1050) that corresponds pretty well with the dip in sunspot activity, followed by another rise at 1100 AD.
Where is the problem? Bearing in mind that we're comparing two different processes (sunspot activity vs. global temperatures), defined by different sets of data (ice core Beryllium-10 concentration vs. tree-ring data and low-resolution proxies), that happened at different places around the globe, I think its striking how well the curves track.
Not really. Using the red Antarctic curve for comparison (neither the Greenland or GRL curves go back far enough), the sunspot activity does show an MWP, it just starts a little before the MWP begins (using the Moberg curve for comparison) at about 950, dips for a bit at 1050 (notice how the Moberg curve's temps also dip), and picks up again at 1100 or thereabouts. Pretty close match, considering the MWP is supposed to have happened between 800-1300 AD.
N.B.: Don't use the Mann et al 1999 curve for comparison, it doesn't work as well because his MBH team smoothed out the Medieval Warm Period and Little Ice Age. But that's another story...
That's what I disagree with. CO2 levels and global temps have never tracked over 600 million years. Except for the theory that falling CO2 levels caused the Ordovician ice age and extinction -- an interesting theory, but not a likely as the Gondwana freezover theory--there's no other instance where CO2 drove global temps.
I agree that a 20X increase in CO2 isn't as big as it sound (I'm arguing that it has a minimal effect even at that level), but if a 30% increase is enough to raise temps up to 4.5 degrees C in a short time, according to the IPCC, why wouldn't a 20X increase increase temps by an equivalent amount? I was not aware that climate sensitivity is logarithmic where CO2 is concerned (probably because of it only being present in trace amounts in the atmosphere). The fact seems to support my argument more than yours, because, if it's logarithmic, maybe a 30% increase in CO2 is completely negligible and you have to get increases of 2000X (guessing again) or more to see a difference.
The Earth's albedo has changed radically over millions of years: Ice Age, the albedo's high, Age of Dinosaurs, not so much. The albedo changes, CO2 levels rise and fall, yet global temps remain stable. I think much of the increase in CO2 over the millennia is caused by the huge increase in lifeforms. Our current environment is almost empty of life compared to the ecosystems of the Paleozoic and Mesozoic periods. If organisms account for 38% of the CO2 in the air today, they must have been blowing out hundreds or thousands of times more of it back then.
My understanding from discussing GW with others is that CO2 from volcanoes has little impact on the climate because it can't get high enough into the atmosphere to make changes. As for other aerosols, over a half billion years, don't you think we'd have several cases of CO2-driven warming? As I've mentioned before, that Appalachian Mountains theory flies in the fact of other theories that have pretty good evidence backing them up. It reminds me of the worries that increasing CO2 would flood the the North Atlantic, disrupting the oceanic "conveyor belt" and sending us into a snap ice age (like in that documentary "The Day After Tomorrow"). Turns out that, while they've got a good theory, it would take orders of magnitude more fresh water to have that effect than can possibly be generated by AGW. Similarly, I'm sure that eroding down the Appalachians could cause local chemical effects that might lower local CO2 levels, but it wouldn't have a global impact.
So it comes back to the beginning of this discussion. I think there are factors causing global w
Of course I can, CO2 is a greenhouse gas, one of many trace greenhouse gases in the atmosphere. It effects the climate, but that effect is minimal. Mess with the concentration of water vapor in the atmosphere, then you have a major effect on climate.
Please explain what other forcings might possibly counteract high global temps being caused by CO2 levels 17.5 times higher than today's levels.
Thanks for pointing out the references, I'll look 'em up.
And I have not claimed that CO2 doesn't impact global temps, it's just that historically, the record shows that global temps do their own thing, regardless of what the CO2 levels are doing. Unless there was a cosmic changing of conditions that obtained 600 million years ago, we're still dealing with the same major players: Earth & Sun. When CO2 dropped from 7000 ppm to 400 ppm while average temps remained within a 10-degree C band, that's such an enormous change in CO2 that there should have been a parallel change in temps. Of course, since the IPCC is claiming a 30% increase in CO2 will cause a 2 to 4.5 degrees C jump in temps, when CO2 levels were at 7000 ppm, global temps must have been around (guessing) 500 degrees C, right? Obviously they were not. Even though we're dealing with paleo climate, we have enough data that we can be sure the Earth's temp wasn't hotter than a volcano.
I read the article you cited on the erosion of the Appalachian mountains sucking up all the CO2 and thereby causing the Ordovician ice age, I just don't agree with it. I prefer this theory:
It jives much better with what we know about atmospheric CO2: 38% is caused by respiration, 57% by the oceans. Freezing the water would have done away with ocean generated CO2 and freezing the planet in general would have killed off the organisms whose respiration provided the balance.
Temps drop, things freeze, CO2 levels drop. Not the other way around.
As for my bringing up the extinction periods, yeah it was off topic, I just find it fascinating that the conditions we live in, given the history of the planet, should be considered dire, yet we act as though that's the natural state of things. Anyway, I shouldn't have mentioned it.
You know, their models say that an increase in CO2 by 30% causes temps to increase by 4 degrees. So when they were 7000 ppm, temps should have been some outrageously high reading, but they weren't. That runaway effect that didn't happen. Because the climate isn't sensitive to changes in CO2.I was already familiar with the Wikipedia cite, what other papers did you refer to?
You say the CO2 emissions correlate with global temp curves, did they cause the Medieval Warming Period or Holocene?
No.
Other than solar activity, the only explanation for the extraordinary Holocene warming is a recent (1999) theory that the Earth's tilt may have changed for a couple thousand years. That theory is based on a model, there's no evidence as of yet. But it could be that the change in tilt and unusual sunspot activity caused the warming.
So maybe it's manmade CO2 and sunspots together causing the current warm spell?? Possibly, except that the Earth's history shows the global climate has little sensitivity to CO2 levels. For example, over the last 600 million years:
- CO2 levels have dropped from 7000 ppm to approx 400 ppm
- Average global temps have remained steadily within a 72F (22C) to 54F (12C) range while CO2 levels have plunged to current levels These fact alone show that the Earth's climate is not as sensitive to changes in CO2 levels as the models indicate
Finally, there have only been three periods during which temps have been as low as they are today, and the other two took place during mass extinctions (Ordovician and Permian). Also, the Permian extinction period is the only other time when CO2 levels have been as low. Just another coincidence? Or proof that we're in an unstable period of cooling and the Earth's climate is eventually going to get warmer no matter what we do.
So there you have it: wide swings in CO2 levels have occurred at the same time temps have remained relatively stable; certainly there haven't been runaway greenhouse effects that the current models would lead us to expect. In short, I question your science.
Look, you have to explain more clearly because it's not easy to understand your point.
For argument's sake, let's say sunspots are twice as numerous as they've been in a millennium. The stock market's at an all time high too, does that mean it's because of sunspots? Hardly likely, because there's no connection we're aware of between stock prices and sunspots.
Ah, but global temps are also shooting up at a very fast rate, in fact the rate of increase strongly resembles the rate of increase in sunspots. Coincidence? Possibly. But as the Sun does control our climate, it's much more likely that the activity causing increased sunspots is also causing increased temps on Earth.
Especially when past history shows two other warm periods that also happened at periods of unusual solar activity.
I'm not turning ""sunspot number" curves into "temperature anomaly" curves", I'm comparing anomalous behavior in sunspots over a period of time with global temps. When you see the following:
- Temps are higher than they've been since the Medieval Warming period, and before that the Holocene period.
- Sunspot activity is higher than at any time since the Holocene period
- Sunspot reconstruction curves track pretty well with global temps (at least as well as global temps track with each other) and the curves shoot up in the same proportion as the global temp curves do.
It's proper to infer that sunspots are responsible for the warming we're experiencing.
Take a close look at this black GRL line in these curves, it does shows a drop in activity around 1950 (but even the low was still much higher than the average over the last 1000 years) and it's since bounced back up again.
Wikipedia
It got even warmer than that in places:
Abstract from "Noble Gas Thermometry and Hydrologic Ages: Evidence for Late Holocene Warming in Southwest Texas"
And other recent research is finding that sunspots were largely responsible for the Holocene warming:
No, we haven't.
Take a look at this graph. There are two set of curves, one comparing the Mann hockey stick to curves showing sunspot activity. The other compares the Moberg 2005 curve to the same sunspot curves.
Here's what I find interesting:
- The Moberg curve (blue curve) follows the Antarctic curve (red) pretty closely, but it tracks almost exactly the same shape as the Greenland curve (green) when it sweeps up in a steep curve in the 20th century.
- The hockey stick curve (orange curve) doesn't do as good a job of tracking with the sunspot curves, in fact it looks like it averaged out the highs and lows (read "MWP" and "LIA") to come up with a relatively smooth shape, but even so, it's still a fair match to the sunspots, especially when it sweeps upward in the 20th Cent.
This can't be coincidental, can it? The obvious conclusion is that the global temps are heavily influenced by sunspot activity. If mankind's pouring of CO2 into the atmosphere was a major influence, the curves wouldn't track together so closely (i.e., the steep upswing would be much greater for the Moberg and Mann temp curves than the sunspots), but that's not the case.
FYI: The sunspot reconstructions I took from Usoskin's millennium-scale sunspot number reconstruction published in the November 2003 issue of Physical Review Letters. There's more current research that was just released, but I can't find the link I had to the PDF. The black GRL curve is from that more recent paper and you can see that it matches the others pretty well.
If the relationships I've drawn are correct, doesn't this strongly imply that the Sun is causing this warming trend?
If you don't think the sunspot curves match closely, it may help to see how poorly the various global temp curves match with each other. Take a look at this Wikipedia graphic combining the global temperature reconstructions from the major players. Looks pretty random to me. The only thing that's given them any credibility is that they all swoop up in the 20th century like they're heading for the moon. And so do the Greenland and GRL sunspot number curves.
Based on that, take another look at the SN curves and then at this one where the curves are overlaid on the Wikipedia graphic.
I'd say the SN curves track better with the global temp reconstructions than many of the wilder global temp curves do. Yet all those curves have been cited by "warmists" as being equally valid (because of that lovely swoop!).
Yup, it's the Sun causing the warming!
There's not a lot, but try these links for starters:
Enrico Fermi Nuclear Generating Station
Fast breeder reactor - History in USA
Dangerous encountersAs it turns out, I do. From Studies of Nuclear Hazards and Constitutional Law:
"Going with breeder reactors and other more efficient designs would be good too." Probably, but the closest we've come to a nasty meltdown/nuclear explosion was when the Enrico FermI fast breeder reactor near Detroit, MI lost coolant because a piece of metal blocked the liquid sodium coolant nozzles. They shut that puppy down just in time--if they'd been a few seconds slower, a chain reaction of nuclear explosions could have caused plutonium in the core to be blasted skyward. The last I read, less that a tenth the size of a grain of sand is more than enough plutonium to kill you, so such an explosion at the Fermi plant could have affected millions. I like water-cooled nukes; there's more waste to deal with, but they're much safer than the breeders.
Oh, Futurama....never watched it so I supposed he was making a point. Was it funny when they said it on the show?
Dude, you've got to unbunch your undies over global warming. The Earth's temp doesn't rise when you run your mower or have a barbeque. The worst that could possibly happen is we get a few degrees warmer (woohoo!), the ocean a little deeper, and we could finally stop worrying about those pesky ice ages every few millenia.
At its worst, when CO2 levels were some 20 times higher than today, average temps were 22 deg C (74 deg F). Plus temps remained that high for millions of years after CO2 levels dropped to near current levels, so it's not the highly sensitive feedback system GW proponents generally claim. Warmer than we're used to, but there's always A/C! Because face it, we're not causing this warming spelll, it's been in the cards for a while now and there's nothing we can do to stop it.
As for the ocean's getting deeper, do you realize that if we could make a law forbidding people living closer than 20 miles to a shoreline, we'd save hundreds of thousands of lives today! Take the step of moving people from the vulnerable shorelines and you take away the biggest impact from GW.
Anyway...seriously, the amount of diesel fumes would be trivial in comparison to the amount of fresh water delivered. Plus we could develop nuclear tugs! It's all good.
What's to be excited about lately in space exploration? Another photo of Martian desert that looks like Barstow? (h/t Dennis Miller) When I grew up reading Heinlein and Niven, there might dragons on Venus, dying civilizations on Mars...interesting stuff. Instead we get scenic photos of Jupiter and Saturn (thanks!) and daily weather reports on Mars. Everywhere we look it's all negatives: sterile, too hot, too cold, air too thin or too thick, gravity too heavy, etc. Sheesh, thermal vents on the ocean floor are more interesting and alien than anything we're likely to see in this solar system! And Hubble still hasn't detected one Dyson sphere or Ringworld! I can't get excited by shuttle missions because they're like bus trips: carry cargo up, maybe fix a satellite, fly back down. Other than the spectacular liftoffs and dangerous environment, it's somewhat like watching a FedEx jet do its job day after day. Whereas with my iPod, I can close my eyes and imagine while listening to audiobooks of Heinlein, "Doc" Smith, and Brin. Advantage: iPod
Hook the ice shelf up to some powerful tugs and drag it down to Australia! They're having a drought y'know and could use the fresh water
Good post, I'd mod you up if I had the points. As you're not hammering the U.S., however, prepare to be modded to oblivion.
Just wanted to let you know that you deserve +5 Insightful for this post! Unfortunately, the biased /. moderators will no doubt crush you.
SUV vs. car: people in car survive if they are properly restrained
What if a ninja is driving the car and Aquaman is behind the wheel of the SUV, who survives then?
Good point! I keep forgetting that Canada isn't the 51st state.
Yeah, but the US has never lost the World Series. Ever. Must be some kind of miracle!
So http://www.cnn.com/2003/WORLD/europe/08/21/france. heatwave/index.html/ 10,000 French won't die of the heat this summer?
"Oh shut up, you are so stupid."
Applause! Anonymous Coward. Such a glittering example of open-minded discussion.
"What a load of crap. Why are you making such a generalization?"
Because I'm responding in kind to someone who painted with an equally broad brush. If you had posted with a real name, we could have carried on a conversation of specifics, but you chose instead to be an Anonymous Coward.