From an Oregon State University Media Release (h/t to Leif Svalgaard)
Long debate ended over cause, demise of ice ages – may also help predict future
)
The above image shows how much the Earth’s orbit can vary in shape.
This process in a slow one, taking roughly 100,000 to cycle.
(Credit: Texas A&M University note: illustration is not to scale)
CORVALLIS, Ore. – A team of researchers says it has largely put to rest a long debate on the underlying mechanism that has caused periodic ice ages on Earth for the past 2.5 million years – they are ultimately linked to slight shifts in solar radiation caused by predictable changes in Earth’s rotation and axis.
In a publication to be released Friday in the journal Science, researchers from Oregon State University and other institutions conclude that the known wobbles in Earth’s rotation caused global ice levels to reach their peak about 26,000 years ago, stabilize for 7,000 years and then begin melting 19,000 years ago, eventually bringing to an end the last ice age.
The melting was first caused by more solar radiation, not changes in carbon dioxide levels or ocean temperatures, as some scientists have suggested in recent years.
“Solar radiation was the trigger that started the ice melting, that’s now pretty certain,” said Peter Clark, a professor of geosciences at OSU. “There were also changes in atmospheric carbon dioxide levels and ocean circulation, but those happened later and amplified a process that had already begun.”
The findings are important, the scientists said, because they will give researchers a more precise understanding of how ice sheets melt in response to radiative forcing mechanisms. And even though the changes that occurred 19,000 years ago were due to increased solar radiation, that amount of heating can be translated into what is expected from current increases in greenhouse gas levels, and help scientists more accurately project how Earth’s existing ice sheets will react in the future.
“We now know with much more certainty how ancient ice sheets responded to solar radiation, and that will be very useful in better understanding what the future holds,” Clark said. “It’s good to get this pinned down.”
The researchers used an analysis of 6,000 dates and locations of ice sheets to define, with a high level of accuracy, when they started to melt. In doing this, they confirmed a theory that was first developed more than 50 years ago that pointed to small but definable changes in Earth’s rotation as the trigger for ice ages.
“We can calculate changes in the Earth’s axis and rotation that go back 50 million years,” Clark said. “These are caused primarily by the gravitational influences of the larger planets, such as Jupiter and Saturn, which pull and tug on the Earth in slightly different ways over periods of thousands of years.”
That, in turn, can change the Earth’s axis – the way it tilts towards the sun – about two degrees over long periods of time, which changes the way sunlight strikes the planet. And those small shifts in solar radiation were all it took to cause multiple ice ages during about the past 2.5 million years on Earth, which reach their extremes every 100,000 years or so.
Sometime around now, scientists say, the Earth should be changing from a long interglacial period that has lasted the past 10,000 years and shifting back towards conditions that will ultimately lead to another ice age – unless some other forces stop or slow it. But these are processes that literally move with glacial slowness, and due to greenhouse gas emissions the Earth has already warmed as much in about the past 200 years as it ordinarily might in several thousand years, Clark said.
“One of the biggest concerns right now is how the Greenland and Antarctic ice sheets will respond to global warming and contribute to sea level rise,” Clark said. “This study will help us better understand that process, and improve the validity of our models.”
The research was done in collaboration with scientists from the Geological Survey of Canada, University of Wisconsin, Stockholm University, Harvard University, the U.S. Geological Survey and University of Ulster. It was supported by the National Science Foundation and other agencies.
UPDATE: Science now has the paper online, which is behind a paywall. The abstract is open though and can be read below:
| Science 7 August 2009:
Vol. 325. no. 5941, pp. 710 – 714 DOI: 10.1126/science.1172873 |
Research Articles
The Last Glacial Maximum
Peter U. Clark,1,* Arthur S. Dyke,2 Jeremy D. Shakun,1 Anders E. Carlson,3 Jorie Clark,1 Barbara Wohlfarth,4 Jerry X. Mitrovica,5 Steven W. Hostetler,6 A. Marshall McCabe7
1 Department of Geosciences, Oregon State University, Corvallis, OR 97331, USA.
2 Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8, Canada.
3 Department of Geology and Geophysics, University of Wisconsin, Madison, WI 53706, USA.
4 Department of Geology and Geochemistry, Stockholm University, SE-10691, Stockholm, Sweden.
5 Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA.
6 U.S. Geological Survey, Department of Geosciences, Oregon State University, Corvallis, OR 97331, USA.
7 School of Environmental Science, University of Ulster, Coleraine, County Londonderry, BT52 1SA, UK.
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I am assimilated by PDO. If the Earth plunges into another Ice Age, we will return to the Stone Age, and all that coal & oil in the North will be buried under a mile of ice. Our age will be a strange blip in the geologic record that future geologists will puzzle over. Where’d that radiated soot layer come from? No one will e – ver know.
wattsupwiththat (06:11:17) :
Of course this is nothing new, nobody doubts the role of CO2 in providing a portion of the warming effect, so also does water vapor. But it is a lag effect of CO2 released in response to the change in earth’s wobble and thus not the main driver of the event.
I would say a small and lagged portion of the warming effect.
Consider:
Water vapor rises immediately according to the heat of the air over the oceans, not according to the temperature of the oceans. The sun heats the air immediately, the oceans slowly. CO2 has a 800 to 2000 year lag in response, while the oceans warm and the permafrost melts.
In addition CO2 is less than 10% in contribution to the green house effect of the contribution of H2O.
I am always amazed how people postulating runaway effects from GH gasses can ignore these simple physical characteristics of H2O and can still look at ice age records and talk of CO2 feed backs at the time. It invalidates for me any worth in their paper.
[snip – rant]
anna v (21:16:14),
Excellent post, as always.
Nassif Nahle wrote:
“To qualify carbon dioxide as a secondary amplifier of the Earth’s atmosphere warming, answer the following questions:
What’s the absorptivity-emissivity of carbon dioxide at its current partial pressure in the atmosphere?”
This question is answered by Modtran based on the HiTran data base:
http://en.wikipedia.org/wiki/MODTRAN
“MODTRAN (MODerate resolution atmospheric TRANsmission) is a computer program designed to model atmospheric propagation of electromagnetic radiation from 100-50000 cm-1 with a spectral resolution of 1 cm-1.
The spectral region covered is the far-infrared (100 cm-1 is 100µm wavelength), through visible light, to the deep ultraviolet (50000 cm-1 is 200 nm).
Some aspects of MODTRAN are patented by the US Air Force. Software licenses are issued by the USAF but distribution is handled by Ontar Corporation. MODTRAN core modules are written in FORTRAN.”
The answer to your question depends on the partial pressure, altitude and temperature.
“What’s the total emittancy of carbon dioxide at its current partial pressure in the atmosphere?”
I am not familiar with the word emittancy. If you mean emissivity this can be found for whatever conditions you like using MODTRAN.
“What’s the real value for climate sensitivity to carbon dioxide?”
This is uncertain the nominal value seems to be about 3C with a range of +/- 1.5.
“What’s the heat capacity of carbon dioxide at its current density in the atmosphere?”
A question that is irrelevant to the understanding of how CO2 influences the radiation balance of the earth’s atmosphere. Collisions between CO2 and other molecules in the atmosphere will distribute the energy absorbed by CO2
to the air as a whole. The heat capacity of air depends on its pressure.
What’s the specific heat capacity of carbon dioxide at its current density in the atmosphere?
“What’s the thermal diffusivity of carbon dioxide at its current density in the atmosphere?”
Also an irrelevant question. CO2 is spread from its sources through the atmosphere by the motion of the air due to winds.
“What’s the specific volume of carbon dioxide in the atmosphere at the present time?”This depends on the temperature and pressure. Assuming CO2 is close to an ideal gas
V=RT/PM, where M is the mass of a mole of CO2 or approximately 44gms.
R is the ideal gas constant and T is the absolute temperature.
What’s the real effect of carbon dioxide in the atmosphere?
It absorbs specific bands of radiation and emits raditiation in all directions equally. As a result of this less radiation emitted from the surface leaves the earth atmosphere system than would be the case without it. The effect of CO2 is amplified by the ability of water to vaporize at higher densities in the atmosphere with increasing temperature. The presence of absorbing gases in the atmosphere makes the temperature of the earth’s surface 33C warmer than it would be without them, and reduces the difference in temperature between day and night, allowing for the survival of complex life forms.
And the North pole is still frozen.
I don’t question the role of the carbon dioxide on rising a little (almost nothing) the temperature of the atmosphere.
I do question the magnitude of the increase caused by the carbon dioxide and do reject absolutely the argument of taking the carbon dioxide as a black radiator with an emissivity of 50% just because it is not real.
The flux of heat from the surface (land and oceans) to the atmosphere is continuous, day and night, thus, if carbon dioxide had a radiative power of 50% for emissivity and 50% for absorptivity we had been toasted long ago.
There is no heat retained by the atmosphere. If heat was retained, it would be as potential or kinetic energy and it would stop being heat, that is, energy in transit or energy in the moment of being transferred from one system to another.
Water and mud have the capacity of store energy many times more than the carbon dioxide. For example, during a change of temperature of 0.8 K, the dry air absorbs 956.16 J; liquid water absorbs 3.352 x 10^6 J; and dry clay soil absorbs 1.424 x 10^6 J.
What is the system or systems that maintain the entropy of the air in a quasi-stable state? From the results in the previous paragraph, the systems that maintain the temperature of the air are water and dry clay soil.
Insolation in the first place, the surface in the second place (Peixoto & Oort. 1992. Page 233). The air (carbon dioxide included) is a distributor of heat and a drainer of heat from the surface to the outer space. Water vapor retains heat, so it is the main cause of the “greenhouse” effect. The time the heat spends in crossing the medium, i.e. the time that the energy spends transiting from one molecule to another molecule, is what is called “greenhouse” effect. Remember, the Earth is not an isolated system in the cold, 3D, unbounded and infinite space.
Resources:
Peixoto, José P., Oort, Abraham H. 1992. Physics of Climate. Springer-Verlag New York Inc. New York.
For carbon dioxide absorptivity:
Pitts, Donald and Sissom, Leighton. Heat Transfer-Second Edition. © 1998 McGraw-Hill Companies Inc.
For water absorptivity:
Chaplin, Marin. Water Absorption Spectrum. http://www.lsbu.ac.uk/water/vibrat.html (Last reading on 25 April 2009).
For values of heat capacity of water, air, carbon dioxide and clay:
Boyer, Rodney F. Conceptos de Bioquímica. 2000. International Thompson Editores, S. A. de C. V. México, D. F.
You can read the article at most public libraries (based on a survey of the local libraries west and northwest of Boston). Many will not have it cataloged and shelved yet, but almost all librarians will get it out of the queue if you ask.
eric (21:50:35):
You’ve got an “F”… Sorry.
Here is where I think we are regarding the arrival of the next ice age. It’s already here, it’s just slow and steady, the backdrop behind the noise…
Here’s a graph containing a comparison of GISP2 (Greenland) Northern Hemisphere, and Vostok (Antarctica) Southern Hemisphere. I interpolated the GISP2 and Vostok to have common data points to be able to average the two (the green line in the graph, with trend lines). That’s my best guess as to what “global” temps actually might have been for this interglacial (average the two best ice sheets for each hemisphere). I’ll disregard the hockey stick (NH) pasted onto the Vostok (SH) record thank you.
http://s852.photobucket.com/albums/ab89/etregembo/?action=view¤t=GISP2_VOSTOK_INTERGLACIAL.jpg
Looks to my eyes like we’ve been entering the next ice age for about 3500yrs now (judging by the green average line), and riding the current wave of 1186yr spikes which might not peak until 200yrs from now if you extrapolate from the last 3, being the MWP, RWP and the one before that which peaked at roughly 3100yrs ago.
Also observable is the obvious saturation effect from the next graph (glacial and interglacial), where the 1186yr spikes are of much higher amplitude during the glacial period, and severely attenuated but discernible during the interglacial . No implication of runaway temperatures here.
http://s852.photobucket.com/albums/ab89/etregembo/?action=view¤t=GISP2_Vostok_50K.jpg
The signal attenuation would seem to support the theory that climate sensitivity decreases with increasing temperatures (regardless of whether CO2 or H2O driven feedback). The same signals are present during both the glacial and interglacial, are severely attenuated during the interglacial (surprisingly so IMO). But when you consider the Vostok record and how repeatable the Min/Max is, it really shouldn’t be. The system has rails/saturation characteristics that make life so comfortable (relatively speaking) but yet allow some evolution pressure.
Also note the longer term trends during the interglacial (first graph) whereby the Northern and Southern Hemisphere are always diverging (outside of the main interglacial signal which effected both hemispheres). Seems to me this could be that the NH is the main receiver of solar radiation and when heating, initiates cooling in the SH, or that there is a wobble in the obliquity signal which we aren’t yet aware. Anyway, the NH starts entering the Interglacial first, but the Younger Dryas event occurs (a 1186yr spike subsides). The southern hemisphere enters the interglacial and reaches the somewhat saturated shelf of the interglacial, while the NH is in the Younger Dryas event. Then the SH stays pretty flat, while the NH enters the interglacial. Once the NH trends starts to decrease around 8kyrs, the SH trends oppose and increase, peaking at ~5500yrs, where the NH reaches a low point. Then they switch again, reaching another opposition point at roughly 3500yrs, whereby they both start decreasing until the LIA, where they again have opposition with the NH at a null, and the SH at a peak during the LIA.
If I were to predict temperature trends based on this graph, I would say that we are entering the next ice age (and have been for 3500yrs), but we are finishing a recovery from the LIA (a 6200yr NH null that shows up drastically in the 14C record (I’d have to hunt for that graph, forcing agent source unknown…cosmic?). I’d expect NH temps to increase during the recovery from the LIA (simliar to the event that occurred at 5200yrs), and potentially the NH to peak 200yrs from now. If it were to increase another 0.5C by 200yrs from now, it would still fit in nicely with natural cycles. I’d also say, enjoy the next conjunction of the low point of ocean cycles and solar activity, as it should resume after 2035 or so (as many others suggest).
That’s my two cents. Hope the links work…
Ed
Here is the 6200yr cycle referred to above (which coincides with the LIA and the similar NH null at ~5500yrs ago).
http://s852.photobucket.com/albums/ab89/etregembo/?action=view¤t=10Be-C14-Comparison.jpg
Leif Svalgaard (07:01:48) :
idlex (06:20:40) :
“I think the consensus is that we can do this accurately [enough for this purpose] for some millions of years.”
Really?
Yes, [enough for this purpose]
………………………………………………….
There is no problem with a qualitative description of this process, but the quantitative solutions, via geometry and heat and perturbations upon both, are not quite so simple.
A poor analogy is that satellites need fuel for in-flight corrections to their paths because the paths cannot be modelled accurately enough at launch. What makes us think that we can model the earth orbit well enough so we can predict remperature changes caused by geometry changes? How about some error estimates?
Old Science is New Science
This was discovered in 1976
See http://osec.rutgers.edu/ebme/HistoryEarthSystems/HistEarthSystems_Fall2008/Week12a/Hays_et_al_Science_1976.pdf
Variations in the Earth’s Orbit: Pacemaker of the Ice Ages
J. D. Hays, John Imbrie and N. J. Shackleton
Science, New Series, Vol. 194, No. 4270 (Dec. 10, 1976), pp. 1121-1132
(article consists of 12 pages)
Published by: American Association for the Advancement of Science
Summary
5) The dominant, 100,000-year climatic component has an average period close to, and is in phase with, orbital eccentricity. Unlike the correlations between climate and the higher-frequency orbital variations (which can be explained on the assumption that the climate system responds linearly to orbital forcing), an explanation of the correlation between climate and eccentricity probably requires an assumption of nonlinearity.
6) It is concluded that changes in the earth’s orbital geometry are the fundamental cause of the succession of Quaternary ice ages.
Gosh, whats up with that isotope 12 and 13 marker that identifies that the bulk of the CO2 increase is fuel burning and not from natural sources? Whats up with the fact that the oceans/plants are only able to take out half of what humans are pumping into the air. By comparison, vulcanic sources annual mean is 120 million tonnes. Humans pump out by count of last published figures in 2007, 9.4 Giga Tonnes. So is temperature rise preceding the CO2 ppmv increase or has since CO2 increase overtaken and is now driving temperature increase?
As for precession, what’s new about that http://csep10.phys.utk.edu/astr161/lect/time/precession.html ? What new since Milankovic? Old hat tip I’d say. Very old. The movement has not changed it’s speed, yet the global climate change has. Rutgers reports near record low snow for July. It’s must be global cooling, or no wait it’s the UHT’s doing it?
TIME FOR A NEW PARADIGM ON CLIMATE CHANGE?
There are two alternative ways to look at how science progresses. In one corner is the concept of the
falsifiable hypothesis, credited to Karl Popper. Popper argued that all science is based on hypotheses,
which must be tested to destruction. Sound evidence which does not fit with the hypothesis must logically
cause it to be rejected. However, the other side of the same coin is that no hypothesis can ever be said to be
proven. Over time, the body of evidence consistent with a successful hypothesis builds up to the extent that
it becomes regarded as a theory, for example the theory of General Relativity, or Tectonic Plate theory.
At this stage, theories are treated, to all intents and purposes, as fact. However, even then, quite basic
knowledge may, with time, be seen as merely provisional. A classic example is Newtonian mechanics,
which fully describes the motion of bodies on the scale we are familiar with, but which breaks down both at
the level of elementary particles (hence the development of quantum mechanics) and at a cosmological
scale (where relativity comes into play).
Popper used the concept of falsifiability as his criterion for whether something is genuinely scientific or
not. Thomas Kuhn, in the other corner of this contest, contributed a different view of how scientists work.
He introduced the concept of “normal science” to cover the situation where scientists work on various
topics within a central paradigm. In contrast to Popper, the Kuhnian view is that “wrong” results (ie, those
which are in conflict with the prevailing paradigm) are considered to be due to errors on the part of the
researcher rather than findings which jeopardise the consensus view. However, as conflicting evidence
increases, a crisis point is reached where a new consensus view is arrived at: a so-called paradigm shift.
These two philosophical approaches represent the extremes of a spectrum. Popper is the purist, who
describes how scientific progress ought to work in an ideal world. On the other hand, Kuhn’s description is
more pragmatic and a more realistic view of what actually happens. When a hypothesis is first put forward,
it would be quite easy to discard it if early experimental results falsified it. However, when a consensus
builds up over time that a particular view is “correct”, it takes plenty of hard evidence to convince people
they have been wrong. After all, scientists are only human.
The example often used of this happening in the fairly recent past was the derision which was directed at
Wegener’s hypothesis of continental drift, when the prevailing scientific view was that land masses were
immobile. Although there were some supporters of this view during the first half of the twentieth century, it
was only in the 1950s that an understanding of plate tectonics led to the general acceptance that continents
are not static. This was a revolutionary shift in thinking, but the paradigm took many years to change.
But Popper’s description was more nearly correct in the case of cosmology. In the 1950s, there were two
competing primary models of the Universe: the Big Bang and the Steady State. By the mid-60s, the
accumulation of evidence led most astronomers to accept that the Big Bang was the hypothesis which gave
the better explanation of how the Universe behaves.
Coming now to the more topical and contentious case of climate change, it is clear that science is
operating in a Kuhnian fashion. There are a number of observations which would apparently serve to falsify
the hypothesised enhanced greenhouse effect. Not least of these are the missing signature of CO2-driven
warming (an enhanced rate of warming in the upper troposphere relative to the Earth’s surface) and the lack
of warming across the greater part of Antarctica. The response to this – from those who do not simply
dismiss the evidence out of hand – is to point instead to evidence which is consistent with the AGW
hypothesis and to introduce a range of fudge factors such as aerosols to account for the observed lack of
correlation between atmospheric carbon dioxide level and average temperatures.
The behaviour of a great many researchers involved in climate change is far from Popperian. Rather than
test their hypothesis by trying to falsify it, they look instead for evidence which supports it and, in a deeply
unscientific manner, will often simply dismiss contrary evidence on the basis of minor flaws or criticism.
This is research done according to prejudice rather than with an open mind. To compound the error, and
because evidence can only be gathered by observation rather than experiment, increasing reliance has been
placed on computer models.
Making headlines in the Guardian last week was a study not yet even published. Jointly written by
Judith Lean of the US Naval Research Laboratory and David Rind of the NASA Goddard Institute for
Space Studies and due to appear in Geophysical Research Letters, this is billed as the first analysis of the
combined impact of human influences (including CO2 and aerosols), solar radiation, volcanic eruptions and
ENSO (the El Nino Southern Oscillation) on global temperatures.
Their main conclusions are that anthropogenic global warming has been masked in recent years by
reduced solar activity and a lack of a strong positive El Nino, but that a projected increase in solar activity
will cause temperatures to rise at a rate 50% faster than projected by the IPCC. Many readers will of course
remember that mainstream researchers have generally downplayed the role of variations in the Sun’s output
as insignificant in terms of global temperatures, but there now seems to have been a reinterpretation to fit
the facts.
But the main criticism of this paper (or at least, what has been reported prior to publication) is that it is
not a scientific study but the output of a computer model. The study smacks of damage limitation, of a
desire to find some rational explanation for the lack of temperature rise over the past seven or more years.
The explanation is that well, yes, natural variation can be important, but that this is only creating a
temporary masking effect, soon to disappear. Suspicions about the motivation for the paper are only
increased by the Guardian headline: “New estimate based on the forthcoming upturn in solar activity and El
Nio southern oscillation cycles is expected to silence global warming sceptics”.
Highly unlikely, as this is merely hypothesis and, crucially, it is not directly falsifiable. But what is
important is that the authors are predicting the return of global warming in the next few years, and that the
upward trend will be higher than before. If this does not occur, then we must conclude that their analysis is
wrong. If they are wrong, it may be because the coming solar cycle will be a weak one, as many people are
predicting. And, if so, the logical conclusion may be that natural cycles are more important than carbon
dioxide emissions.
In the meantime, Henrik Svensmark and colleagues from the Danish National Space Centre have
published a paper in the same journal which gives support for the hypothesis that cosmic rays, modulated
by the solar wind, can indeed alter the degree of cloud cover and hence affect temperature (Svensmark et
al; Cosmic ray decreases affect atmospheric aerosols and clouds; Geophysical Research Letters; Vol 36,
L15101, doi:10.1029/2009GL038429, 2009). Their measurements indicate that cloud cover measured over
oceans decreases to a minimum approximately a week after cosmic ray minima. The effect can take large
quantities of liquid water out of the atmosphere. This hypothesis may or may not be right, but it remains a
working possibility and should certainly not be dismissed lightly.
So, climate science, heavily influenced by global warming politics, continues to adhere to a central
paradigm as described by Kuhn. Contrary evidence is clearly not going to be accepted as falsification. It
will be fascinating to see what trends there actually are in climate over coming years and, if the predictions
of renewed (and faster) global warming come to nothing, then what else will be necessary to cause the
crisis which will lead to a paradigm shift. In the meantime, we have to hope that politicians do not take us
too far down the road of trying to control the climate based on the current paradigm.
————————————————————-
The Scientific Alliance 7th August 2009
St John’s Innovation Centre, Cowley Road, Cambridge CB4 0WS
>>Anthony, July and August were originally named Quintilis and Sextilis
>>as the 5th and 6th months of the roman calendar.
I always thought that July and August were the additional months, introduced by Julius Caesar and Augustus Caesar respectively, which is why the later months are all displaced by two.
Month (Latin)
Sept-ember = 7 (septem)
Oct-ober = 8 (octo)
Nov-ember = 9 (novem)
Dec-ember = 10 (decem)
So which are the two extra months?
Bob Ramar (18:21:43) :
There is a real threat however and that is methane. Methane is the fourth most potent greenhouse gas in the atmosphere (after water vapor, argon, krypton, then methane). And a lot of methane is locked up on the seafloor in the form of methane hydrates. However, methane makes a lovely fuel … .
What is the basis for calling methane a threat? I mean, is there any historic evidence at all that large enough quantities of methane has been released over a short period causing noticeable climate change? If not, what is it that makes it a ‘real threat’ now?
Nogw (10:01:45) :
Better let us re-read Velikovsky’s “Worlds in Collision”, a beautiful book of the pre-global warming era.
Velikovsky is an original catastrophist/alarmist attempting to prove references in ancient texts to celestial mysteries (sun stood “still” in the sky) are grounded in fact. His dismissal of plate tectonics sufficiently eviscerates his thesis.
Flanagan and John Finn
Why so excited? You are assuming that once the Milankovitch ‘cycle’ triggered a warming, CO2 took over rather than merely contributed to ongoing warming that was due to the ‘cycle’.
Think about it. From bottom to top there was a change of about 100 PPM and a temp change of about 10C. Hansen calculates sensitivity based on CO2 being responsible for most of that temp change!
So where’s the other 9+ C of warming from the latest increase in CO2 of about 100PPM? Under Hansen’s bed?
Pipeline? You have to show what it is, where it is, how it got there, and how it gets out.
The truth is neither you, nor anybody else, including Hansen, really knows how much of that warming was due to CO2.
But we are certainly getting a clue from current conditions. 100PPM of CO2 is not now nor ever going to give us a 10C rise in temperature.
crosspatch (22:03:23) :
And the North pole is still frozen.
But if you check the images after 1. August, it is clear that the webcam has reached a tipping point, because it is falling over….
On August 1., the horizon was maybe inclined ~10 degrees to the horizontal axis of the image. Yesterday (August 7.) it looks more like ~40 degrees.
http://www.arctic.noaa.gov/npole/
“Eric: Assuming CO2 is close to an ideal gas
V=RT/PM, where M is the mass of a mole of CO2 or approximately 44gms.
R is the ideal gas constant and T is the absolute temperature.”
Since the standard values (in SI units) are R=8.31, T=273, P=101000 and M=0.044, the Volume would be 0.510 cubic meters ?
We live on a planet which had becomes gradually ice bound for some 85,000 or so years before it warms up for a paltry 15,000 or so. We are approaching the end of our current warming period, and our governments are trying to cool the planet, on the unproven assumption reducing CO2 will do the job. I am not persuaded. In any case, increasing CO2, is good for food production and might reduce the glaciers covering northern Europe, Canada and the northern US by a mile or two. The northern hemisphere breadbaskets will no longer supply our current population with food. We will need all the warmth possible.
The current weather patterns started some five million years ago, and for some reason we are afraid of a little increase in world temperature? The seas are currently 100 feet below normal for an interglacial, which suggests our period is not as warm as before. Cold kills, as the change in species indicate over time. I suspect pumping CO2 into the atmosphere to stave off cooling will be equally effective as sacrificing a virgin to the Sun God.
Trust governments to do the opposite of what they should.
Eric,
With regard to Nassif’s question on the temperature sensitivity of carbon dioxide you wrote 3 C with a range of +- 1.5 c.
On its own this is a meaningles answer. Do you mean 3 C for a doubling of Carbon dioxide? If so I can only assume you have included the IPCC assumed feedbacks into this. Have you? If so, what is the sensitivity without feedbacks?
Bugs,
“You have no evidence that the authors put the reference to AGW in because of political pressure. None at all. If you have, I would love to see it.
If you want my opinion as to why they put it in, it’s because they knew their science would be misrepresented by websites like this. And that’s exactly what happened.”
And your evidence is, exactly what?
RW
You state
Wow, you must have been to a really bad university. Your statement does not correspond to a view ever held by any serious scientists. How can the greenhouse effect be “oversimplified”? That doesn’t even make sense.
You are right it was and remains BAD. Real BAD. The most difficult Engineering program and University to enter in the country.
What you and many others do not seem to realize is this:
The atmosphere is a highly complex system with many other processes (like convection). The modern prevailing view that CO2 is a major force behind global temperatures is WAY “oversimplified” and shows ignorance.