I received this presentation of the “Bjerknes Lecture” that Dr. James Hansen gave at the annual meeting of the American Geophysical Union on December 17th. There are the usual things one might expect in the presentation, such as this slide which shows 2008 on the left with the anomalously warm Siberia and the Antarctic peninsula:
Source: James Hansen, GISS
Off topic but relevant, NASA has recently “disappeared”updated this oft cited map showing warming on the Antarctic peninsula and cooling of the interior:
There is also some new information in Hansen’s presentation, including a claim about CO2 sensitivity and coal causing a “runaway greenhouse effect”.
Hansen makes a bold statement that he has empirically derived CO2 sensitivity of our global climate system. I had to chuckle though, about the claim “Paleo yields precise result”. Apparently Jim hasn’t quite got the message yet that Michael Mann’s paleo results are, well, dubious, or that trees are better indicators of precipitation than temperature.
In fact in the later slide text he claims he’s “nailed” it:
He adds some caveats for the 2xCO2 claim:
Notes:
(1)
It is unwise to attempt to treat glacial-interglacial aerosol changes as a specified boundary condition (as per Hansen et al. 1984), because aerosols are inhomogeneously distributed, and their forcing depends strongly on aerosol altitude and aerosol absorbtivity, all poorly known. But why even attempt that? Human-made aerosol changes are a forcing, but aerosol changes in response to climate change are a fast feedback.
(2)
The accuracy of our knowledge of climate sensitivity is set by our best source of information, not by bad sources. Estimates of climate sensitivity based on the last 100 years of climate change are practically worthless, because we do not know the net climate forcing. Also, transient change is much less sensitive than the equilibrium response and the transient response is affected by uncertainty in ocean mixing.
(3)
Although, in general, climate sensitivity is a function of the climate state, the fast feedback sensitivity is just as great going toward warmer climate as it is going toward colder climate. Slow feedbacks (ice sheet changes, greenhouse gas changes) are more sensitive to the climate state.
Hansen is also talking about the “runaway” greenhouse effect, citing that old standby Venus in part of his presentation. He claims that coal and tar sands will be our undoing:
Hansen writes:
In my opinion, if we burn all the coal, there is a good chance that we will initiate the runaway greenhouse effect. If we also burn the tar sands and tar shale (a.k.a. oil shale), I think it is a dead certainty.
That would be the ultimate Faustian bargain. Mephistopheles would carry off shrieking not only the robber barons, but, unfortunately and permanently, all life on the planet.
I have to wonder though, if he really believes what he is saying. Perhaps he’s never seen this graph for CO2 from Bill Illis and the response it gives to IR radiation (and thus temperature) as it increases:
It’s commonly known that CO2’s radiative return response is logarithmic with increasing concentration, so I don’t understand how Hansen thinks that it will be the cause of a runaway effect. The physics dictate that the temperature response curve of the atmosphere will be getting flatter as CO2 increases. Earth has also had much higher concentrations of CO2 in past history, and we didn’t go into runaway then:
Late Carboniferous to Early Permian time (315 mya — 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ).
There’s lots more in this paper to behold in wonderment, and I haven’t the time today to comment on all of it, so I’ll just leave it up to the readers of this forum to bring out the relevant issues for discussion.
I’m sure Steve McIntyre at Climate Audit will have some comments on it, even though his name is not mentioned in the presentation. My name was mentioned several times though. 😉
Hi,
Forgive OT but I don’t know the protocol for posting stuff like this:
I still would like Anthony or somebody to discuss the week or so oddity on the AMSR-E Sea Ice Extent chart. Unlike the other 5-6 years on the chart,2008 is now going sideways for the last week or so. Anna noted that thereis vulcanism in the region. Is there anybody talking about this, since it would seem to be a pretty big phenomenon to totally stop ice formation for over a week in the Artic, especially given the temperatures in the region as we speak: -18 degrees F at the North Pole
Grant
TI: Threat to the Planet: Dark and Bright Sides of Global Warming
AU: * Hansen, J E
EM: jhansen@giss.nasa.gov
AF: The Earth Institute at Columbia University, 405 Low Library, 535 West 116th Street, New York, NY 10027, United States
AU: * Hansen, J E
EM: jhansen@giss.nasa.gov
AF: NASA Goddard Institute for Space Studies, 2880 Broadway, New York, NY 10025, United States
AB: Abstract. Earth’s history reveals that climate is sensitive to forcings, imposed perturbations of the planet’s energy balance. Human-made forcings now dwarf natural forcings. Despite the climate system’s great inertia, climate changes are emerging above the ‘noise’ of unforced chaotic variability, and greater changes are ‘in the pipeline’. There is a clear and present danger of the climate passing certain ‘tipping points’, climate states where warming in the pipeline and positive feedbacks guarantee large relatively rapid changes with no additional climate forcing. The fact that we are close to dangerous consequences has a bright side: we must reduce greenhouse gas emissions to a level that will minimize many impacts that had begun to seem almost inevitable, including ocean acidification, intensification of regional climate extremes, and fresh water shortages. Actions required to stabilize climate, including prompt phase-out of coal emissions, are defined well enough by our understanding of the climate system, the carbon cycle, and fossil fuel reservoirs. These actions would also yield cleaner air and water, with ancillary benefits for human health, agricultural productivity, and wildlife preservation. Yet the actions required to stabilize climate are not being pursued. Denial of climate change by the fossil fuel industry and reactionary governments has been replaced by ‘greenwash’. The policies of even the ‘greenest’ nations are demonstrably impotent for the purpose of averting climate disasters. I conclude that inaction stems in large part from ‘success’ of special financial interests in subverting the intent of the democratic process to operate for the general good. The consequence is intergenerational inequity and injustice, affecting negatively the young and the unborn. The defense of prior generations, that they ‘did not know’, is no longer viable. Indeed, actions by fossil fuel interests that served to deceive the public about the dangers of human-made climate change raise questions of ethics and legal liabilities. Youth, at least those who are not too young or unborn, have recourse through democratic systems, but continued failure of the political process may cause increasing public protests.
The Dark and Bright Sides of Global Warming James Hansen August 13, 2008 YouTube
The Threat to the Planet: Dark & Bright Sides of Global Warming PDF
Jim Hansen, 3 October 2007, presented at conference: Heating Up the Energy Debate, Gustavus Adolphus College, St. Peter, Minnesota
What Hansen critically fails to realize is that liquid fuel is critical to our civilization – and his job. The looking decline in global petroleum production (“Peak Oil”) will enforce rapid reductions in available liquid fuels to fuel importing countries like the US. See:
Robert L. Hirsch The Inevitable Peaking of World Oil Production Peaking of world oil production: recent Forecasts
US Department of Energy/National Energy Technology Lab., NETL-2007/1263 |
year = 2007, February 5, (The “Hirsch report”), and Mitigation of maximum world oil production: Shortage scenarios Vol 36 # 2, Feb. 2008, 881-889
Our critical issue is not whether the ocean will warm 1 or 1.5 feet, but whether we will have the fuel to run tractors, trucks and to drive to work.
Note especially the World Export Model. Khebab, Graphoilogy, especially slides 16 and 17.
We can convert oil sands and coal to fuel. Sasol of South Africa has successfully been producing oil from coal since 1955.
I would like to see how Hansen proposes to run cars or planes on sequestered CO2. It is our future and our children’s that Hansen is unwittingly destroying in his zeal. Obama’s buying into Hansen’s perspective means much worse economic times ahead in that the US will be even more unprepared for operating on 75% less fuel than we currently use!
Jim G
December 21, 2008 12:34 pm
Here’s one of my favorite Hansen charts. http://pubs.giss.nasa.gov/abstracts/1974/Lacis_Hansen_1.html
pg 119 shows solar energy vs wavelength in w/m
it also shows dark bands corresponding to absorption by (O2, O3, CO2, H2O)
CO2 appears to only effect low energy wavelengths.
But water vapor on the other hand….
So what happend to “If it looks to good to be true than it probably is ?”
Does he really think that the debate will be over now that he has nailed it? This is pure politics, and he knows it, its all or nothing now.
Bill Illis
December 21, 2008 12:42 pm
Just reading the deep ocean response time section of the presentation (of interest to me) and I can’t believe all the “if, then” “on the other hand, if, then ..” over and over again.
It does say most of the models predict it will take well over 1,000 years before the oceans fully adjust to the surface temperature.
Then there is no answer to the question of if it take the oceans 1,000 years to adjust (or in other words, 1,000 years to absorb heat from the surface) what does that do to the surface temperature response time – does it also take over 1,000 years – no answer to that important question – just more “aerosols are masking the warming which has occurred.”
foinavon
December 21, 2008 12:52 pm
It’s worth pointing out the essential fallacies represented in the two graphs presented in Anthony’s introductory post:
(i) the Illis temp vs [CO2] graph of Bill Illes (who he?) is very misleading since it is dominated by the very large temperature changes occurring over the very low [CO2] ranges (0-50 ppm) never experienced on earth.
It’s easy for anyone with the most basic graphing program (e.g. Excel) to see this for themselves.
You can construct essentially the same graph presented by Anthony (Illes) using the equation:
T = (3.0/log(2))*(log(C))-9.39
where C is the CO2 concentration.
So set up a column of X values ranging from 2-3000 ppm. This is C the atmospheric CO2 concentration
In the above equation 3.0 is the climate sensitivity, the log(2) value refers to the fact that this is the temperature increase upon doubling, the log (C) indicates the logarithmic relationship between temperature rise and change in CO2 concentration, and the 9.39 “normalises” the earth’s temperature to 15 oC at at pre-industrial CO2 concentration (280 ppm).
If you then expand the data to observe the relevant bits; i.e. CO2 concentration between 280 ppm and 1000 ppm (to give the extreme value that might be realized in the next 150 years if we didn’t address this problem at all) or 3000 ppm that might be realized under the Hansen scenario of burning all of the coal and tar shale, you can see that very dramatic temperature rise will accrue (and that’s without factoring in other potentially large feedbacks like recruiting all of the methane clathrates in the deep oceans).
(ii) The “Scotese” “graph” is nonsense. Where has it come from? It bears no relation to our understanding of the earth’s temperature and atmospheric CO2 levels in the deep past. I think we all know, for example, that the earth’s temperature hasn’t drifted steadily downwards from ~22 oC 25 million years ago to 12 oC now! And are we really supposed to believe that the earth’s temperature “sat” at a rock-steady 22 oC for many 10’s of millions of years in the past? I think not, and that’s certainly not what the science shows.
..oh well….
Radun
December 21, 2008 12:53 pm
Alternative views (From New Scientist) http://www.newscientist.com/commenting/browse?id=dn16292&page=6
The Consensus Is Fake – Scientists Do Not Agree
Fri Dec 19 15:59:50 GMT 2008 by Benfranklin
I am a skeptic.Global warming has become a new religion. – Nobel Prize Winner for Physics, Ivar Giaever.
Since I am no longer affiliated with any organization nor receiving any funding, I can speak quite frankly.As a scientist I remain skeptical. – Atmospheric Scientist Dr. Joanne Simpson, the first woman in the world to receive a PhD in meteorology and formerly of NASA who has authored more than 190 studies and has been called among the most preeminent scientists of the last 100 years.
Warming fears are the worst scientific scandal in the history. When people come to know what the truth is, they will feel deceived by science and scientists. – UN IPCC Japanese Scientist Dr. Kiminori Itoh, an award-winning PhD environmental physical chemist.
The IPCC has actually become a closed circuit; it doesnt listen to others. It doesnt have open minds. I am really amazed that the Nobel Peace Prize has been given on scientifically incorrect conclusions by people who are not geologists,- Indian geologist Dr. Arun D. Ahluwalia at Punjab University and a board member of the UN-supported International Year of the Planet.
The models and forecasts of the UN IPCC “are incorrect because they only are based on mathematical models and presented results at scenarios that do not include, for example, solar activity. – Victor Manuel Velasco Herrera, a researcher at the Institute of Geophysics of the National Autonomous University of Mexico.
It is a blatant lie put forth in the media that makes it seem there is only a fringe of scientists who don buy into anthropogenic global warming. – U.S Government Atmospheric Scientist Stanley B. Goldenberg of the Hurricane Research Division of NOAA.
Even doubling or tripling the amount of carbon dioxide will virtually have little impact, as water vapour and water condensed on particles as clouds dominate the worldwide scene and always will. – Geoffrey G. Duffy a professor in the Department of Chemical and Materials Engineering of the University of Auckland, NZ.
After reading [UN IPCC chairman] Pachauri’s asinine comment [comparing skeptics to] Flat Earthers, it’s hard to remain quiet. – Climate statistician Dr. William M. Briggs, who specializes in the statistics of forecast evaluation, serves on the American Meteorological Society’s Probability and Statistics Committee and is an Associate Editor of Monthly Weather Review.
For how many years must the planet cool before we begin to understand that the planet is not warming? For how many years must cooling go on?” – Geologist Dr. David Gee the chairman of the science committee of the 2008 International Geological Congress who has authored 130 plus peer reviewed papers, and is currently at Uppsala University in Sweden.
Gore prompted me to start delving into the science again and I quickly found myself solidly in the skeptic camp Climate models can at best be useful for explaining climate changes after the fact. – Meteorologist Hajo Smit of Holland, who reversed his belief in man-made warming to become a skeptic, is a former member of the Dutch UN IPCC committee.
Many [scientists] are now searching for a way to back out quietly (from promoting warming fears), without having their professional careers ruined. – Atmospheric physicist James A. Peden, formerly of the Space Research and Coordination Center in Pittsburgh.
Creating an ideology pegged to carbon dioxide is a dangerous nonsense The present alarm on climate change is an instrument of social control, a pretext for major businesses and political battle. It became an ideology, which is concerning.- Environmental Scientist Professor Delgado Domingos of Portugal, the founder of the Numerical Weather Forecast group, has more than 150 published articles.
CO2 emissions make absolutely no difference one way or another. Every scientist knows this, but it doesn pay to say so Global warming, as a political vehicle, keeps Europeans in the driver seat and developing nations walking barefoot. – Dr. Takeda Kunihiko, vice-chancellor of the Institute of Science and Technology Research at Chubu University in Japan.
The [global warming] scaremongering has its justification in the fact that it is something that generates funds. – Award-winning Paleontologist Dr. Eduardo Tonni, of the Committee for Scientific Research in Buenos Aires and head of the Paleontology Department at the University of La Plata.
Bobby Lane
December 21, 2008 12:53 pm
Slightly off topic…having a little but uncertain hope is worse than having no hope at all. Yet New Scientist, in an article on-line, first says we have reached a tipping point of no return and then says, well, there may yet be a little hope for the Arctic (summer) ice after all. It’s a very confusing article, all based on those infamous oh-so-reliable computerized models.
As you can see from the link, the headline is: Arctic melt 20 years ahead of models. The question nobody seems to be asking, however, is: if this is so, why are the models so incorrect? Could it be that, one way or the other, we really still don’t understand how our complicated planetary climate system works? Like the ending of that tootsie pop commercial says, “the world may never know.” http://www.newscientist.com/article/dn16307-arctic-melt-20-years-ahead-of-climate-models.html
Thomas J. Arnold.
December 21, 2008 12:53 pm
Ed Scott quotes Holdren:
“THE FEW climate-change “skeptics” with any sort of scientific credentials continue to receive attention in the media out of all proportion to their numbers, their qualifications, or the merit of their arguments. And this muddying of the waters of public discourse is being magnified by the parroting of these arguments by a larger population of amateur skeptics with no scientific credentials at all.”
I do not profess to have any grounding in specialist subjects related to AGW but I studied Geography and Geology and Meteorology in some depth at College to degree level. Ergo I am an ‘amateur’, the paranoia with which this site is vilified is interesting, can we not have serious debate? What are the pro man-made GW warming scientists worried about??
If you do not have significant number of letters after your name, then your opinion does not count! Why is this? – can it be that if you do not believe, and are uneducated then it follows that you are not worthy of joining the debate.
Some of us are just saying, “hang on a minute let us test the theory before we commit to these ideas” That surely is the essence of Scientific debate and whether or not you are qualified, this is not relevant. The jury is still out and because a lot of people think one thing, they are not always necessarily correct, just ask Gallileo.
Tom.
David L. Hagen
December 21, 2008 12:54 pm
Hansen cites CO2 in some 16 pages, but only mentions water relating to melting glaciers or ocean level rise.
Hansen fails to clearly show that H2O is 80% of greenhouse gas while CO2 only 20%. Furthermore, we know the least about H2O, especially the precipitation and the water heat conduction mechanisms, especially below the troposphere.
Bobby Lane
December 21, 2008 12:59 pm
Anthony,
Could we then call Steve McIntyre the “Sauron of the Skeptics”? A little Lord of the Rings humor there, but fittingly appropriate. Characters in LOTR often use “the Enemy” or “the Unnamed One” when referring to Sauron. Steve “Sauron” McIntyre? Not a bad monicker. REPLY: I don’t think he’d appreciate the title, but I could be wrong. – Anthony
George E. Smith
December 21, 2008 1:00 pm
Ben,
When you refer to ice core data; just what “data” do you mean ? I would suggest that there is NO ice core data that is more famous world wide, tha the two graphs in Al gore’s “an Inconvenient Truth (p 66/67), and that is simply purported Temperature Data, and purported CO2 data. My understanding is that the CO2 data is actual measured CO2 composition in the samples, and that the “Temperature Data” relies on an O16/O18 proxy; which I don’t claim to understand. how O16 and O18 can simply transmute into each other (or from something else solely as a function of atmospheric temperature is beyond my understanding of atomic Physics (which I once taught0, but that was way back at the start of the space age.
But I am constantly amazed at the ingenuity of scientists at sensing things remotely. My hat is off to Astronomers, who pretty much derive their entire science from the Electromagnetic spectrum for DC to Cosmetic Rays and beyond to unobservable parallel univerese, where any imaginable lwas of Physics can be found.
Now I know those “ice cores” yield a whole lot more substance that just temperature proxies, and CO2 concentrations, and I also know there is a whole lot of skepticism/ debate about just how reliabl;e that stuff is.
But regardless of doubts about the validity of these proxies; it seems to me, that the one thing you can probably count on with some level of credibility, is THE TIMING of whatever happens in those ice cores. They are very tree ring like in their Timing, although I never heard of one tree ring diffusing into otheres to scramble the data. But I generally believe the event timing; unless the lab technicians sometimes screw up.
And therein lies the crux in my mind. In Al gore’s book he deliberately separated those two graphs vertically for the purpose of hiding the true relative timing of CO2 events, and Temperature events.
Well OK he hasn’t had his day in court so maybe I shouldn’t accuse him of outright fraud; I mean it is also possible that he is just as dumb as a box of rocks, and didn’t realize that if he overlapped the curves, one could really see the relative timing of events; sort of what an 8th grade high school science student would do.
Well I have to admit that I have seen the same data printed in peer reviewed journals and other so-called Scientific publications; and actually I have NEVER ever see them overlapped by any author; but I don’t deny that some author/s may exist who have done that.
Bottom line is it is evidently irrefutable that the temperature changes precede the CO2 changes (that caused them) by intervals of from 500 -1500 years, with 800 years appaerntly yielding the highest correlation coefficient.
So regardless of how hokey other ice core evidence may or may not be (I’m not competent to judge that); I don’t se how you get past the usually fatal conclusion that we don’t like our causes happening 800 years after the effect that they cause.
I actually queried Spenser Weart on that point, in Physics Today for Jan 2005 (letters), and he basically changed the subject in his reply, and by e-mail declined to comment further.
Explain the relative timing “anomaly” to me and I’ll die happy.
crosspatch
December 21, 2008 1:02 pm
There are some significant problems with ice cores that aren’t obvious. First of all, Southern Hemisphere ice going to present with a few problems. Antarctica is so huge (twice the size of Australia) and so cold and centered on the pole so it basically makes its own weather. The ice there has survived since long before we had the current cycles of glaciation in the Northern Hemisphere. Also, since it is already so cold there in winter, variations in global temperatures or Northern Hemisphere temperatures might not make that much difference at the South pole.
There really isn’t any analog to Greenland in the Southern Hemisphere where you would have a relatively large land mass with long standing ice. Tropical ice cores would be ideal but there is a major problem with them in that when we go into a Northern Hemisphere ice age, the climate becomes so dry in places like the Andes that the ice disappears for lack of precipitation. The oldest ice core I have been able to learn about from the Andes goes back only 20,000 years and then you hit bedrock. So when we were at glacial maximum in the Northern Hemisphere, the Andes were likely free of snow because of a lack of moisture to produce adequate snow to survive through sunny periods.
New Zealand Southern Alps would seem to be a good candidate but again, the ice doesn’t seem to go very far back in time, nothing found that I know of that goes back before the Holocene. So our ice core records are limited by the looking only at the local climate in Greenland and Antarctica which seem to have had very different local responses to global conditions. We can’t look at Antarctica cores and figure out what things are going to do in the Northern Hemisphere and we don’t have any Northern Hemisphere locations other than Greenland.
That leaves the Himalayas but so far cores seem to give conflicting results in some cases. We just don’t have enough samples from that region to be able to say much. I did find this interesting though:
First, major climatic events from deep sea cores were well recorded in the Guliya ice core. Secondly, the transition from warm to cold periods was abrupt. Third, the temperature fluctuations indicated by the Guliya record are closely related to insolation. It is, therefore, speculated that insolation might be a major driving force of the major climatic events recorded in this ice core.
So here we again show insolation (amount of sunshine) a major driving factor but also we see “the transition from warm to cold periods was abrupt”. Which again would argue against gradual orbital changes being the cause of these abrupt changes. Something else needs to “kick” the system into the other state and the orbital mechanics might be a hysteresis mechanism that keeps it in that state.
The hypothesis I am coming around to is that orbital changes cause a slow change in insolation. Our sun is a variable star. We sometimes have periods of low activity (Maunder, Dalton, etc) which seem to correspond to additional cooling. We also have ocean cycles that seem to be unrelated to these events but also cause some climate impact. When we get into a period of decreasing insolation due to gradual changes in orbit, it might be likely that a period of decreased solar activity might be enough to “kick” the system into a colder stable state. If the solar minimum happens while we are also in a “cold” ocean cycle, it might be even more likely to be a trigger that could switch the state of the system in an abrupt fashion.
Things would then go along until we get into a cycle of increasing solar insolation and have a period of increased solar output, maybe combined with a cycle of warmer ocean climate at the same time and it “kicks” the system into the other state.
This would also explain why we seem to “miss” some 40,000 year periods of opportunity when orbital conditions seem right to come out of the glaciation but don’t. Maybe you need all three conditions to be right. You need the right about of sunlight, the right general trend in sunlight, and be in the right cycle of things in ocean cycle. If we have increasing insolation, and an active sun but the Pacific is in a “cold” phase, it isn’t enough and things stay in the cold state until all three conditions line up again.
The abruptness of the change suggests that something or some combination of things act to trigger a phase change between two stable states. It also seems that the cold phase is the more stable of the two states as the climate seems to stay in that phase 90% of the time and is in the warm state only 10% of the time. Also, overall the glaciation periods have been getting longer meaning it seems to be getting even more stable in the cold state and that might be caused by gradual changes in ocean currents caused by tectonics. As the positions of things change, ocean currents change. We could well at some point get to a situation where the isthmus of Panama opens back up again, we get more equatorial mixing, and the system goes more stable in the warm state as it apparently was some 3-5 million years ago.
But I am just guessing.
PeteM
December 21, 2008 1:02 pm
@Smokey (11:24:08) : On your point
“After reading Hansen’s comparison of the Earth and Venus, I notice that he made no mention of the fact that Venus is much closer to the Sun than the Earth is. Or that Mars’ atmosphere is mostly CO2, and Mars is freezing cold.
….. ”
(a) I’m not sure if you are suggesting that position from the sun is the dominant reason for the the temperature difference between Venus , Earth and Mars .
Mercury is much closer to the Sun (58 million Km) than Venus (108 million km)
Mercury has a temperature of that varies between about 430 C and -180 C. Venus has a temperature of about 450 C with not much difference between night side and sun side.
This can be explained by a run away greenhouse effect on Venus
(http://en.wikipedia.org/wiki/Venus)
(b) Since atmosphere is important ( comparing Venus and Mercury) …why is Mars cooler . Its atmosphere is so thin (about 100th that of the Earth) that even though the CO2 content is hight ( 95%) there isn’t enough to cause a runaway greenhouse effect or mask the effect of its distance from the Sun .
(http://www-k12.atmos.washington.edu/k12/resources/mars_data-information/temperature_overview.html) . Although the CO2 content does appear to have some effect on Mars.
Edward T
December 21, 2008 1:09 pm
I can still access that image here: http://earthobservatory.nasa.gov/IOTD/view.php?id=6502
It was NASA’s “Image of the Day”, pPosted April 27, 2006. REPLY: Thanks for finding that, interesting to note the before and after images they cite. Big difference.
Anthony
It’s also curious when making the comparison to Venus, shouldn’t he mention Venus has no no planetary magnetic field? Because of that, the sun has stripped Venus’ atmosphere of most of the lighter gases, leaving an atmosphere of mostly the heavier CO2 and Nitrogen molecules.
If you are going to do science why not do it completely, why not do it in the open?
It’s as if he thinks no one knows what photosynthesis is. Come to think of it, I asked that very same question to a group of people (I won’t say who they really were) and not one in the crowd knew what it was. So obviously they didn’t have a clue what would happen if we were able and reduced the CO2 in the atmosphere to zero.
foinavon
December 21, 2008 1:27 pm
George Smith:
18O/16O in H2O in ice cores:
This pretty much represents the effect of distillation. It takes more thermal energy to vapourize 18O water than 16O water, and during glacial periods with colder seas, the water vapour is depeleted in 18O water as a result. And as the vapour travels to the polar regions there is anadditional tendency for any 18O water to condense our before 16O water. So when polar precipitation (snow!) occurs, the water is more depleted in 18O(H2O) relative to 16O(H2O), and this can be measured in the ice cores using mass spectrometry.
Timing of CO2 and temperature in ice cores:
Yes, the temperature variations precede the CO2 variations throughout much of the ice core depths. That rresults from the fact that the temperature variations during these events were initiated by insolation changes resulting from the cyclic variations in the earth’s orbital properties. According to the Illes graph that is shown in the introductory article of this thread, rising atmospheric CO2 levels result in warming, and this equates to around 3 oC of warming per doubling of atmospheric CO2. So during ice age cycles the raised atmospheric CO2 concentrations from around 180 ppm to 270 ppm during a glacial to interglacial transition contributed a bit under 2 oC of warming to the total warming transition.
Remember that during the ice age transitions these phenomena were slow, slow slow! So the last glacial to interglacial transition from around 15,000 to 10,000 years ago saw atmospheric CO2 levels rise by around 90 ppm over 5000 years. That’s less than 2 ppm per 100 years averaged ove rthe transition.
Atmospheric CO2 levels are rising over 100 times faster now (of the order of 2.5 ppm per year).
The essential point is that however atmospheric CO2 levels rise (a result of orbital-induced insolation changes during ice age cycles, or direct pumping into the atmosphere on a truly humungous scale now), the enhanced CO2 levels result in enhanced warming of the earth (near 3 oC of warming per dubling of atmospheric CO2 according to a whole load of analyses).
deadwood
December 21, 2008 1:33 pm
PeteM:
Did you even read Kasting’s 1988 paper where he uses the term “runaway greenhouse” occurs? Clearly not. He is specifically linking this term to solar activity during the early stages of planetary evolution causing all the water vapor to blow away into space.
The water it seems, in his one-dimensional atmospheric model, acted as a negative feedback untill it dissipated into space.
Try again Pete, but this time follow-up on your “proof”. Don’t just read the buzz words.
John Galt
December 21, 2008 1:33 pm
Is it possible that Hansen believes nobody will bother to check on his work? Perhaps he believes people will blindly accept everything he says as fact, instead of wishful-thinking-based opinion?
crosspatch
December 21, 2008 1:37 pm
“the enhanced CO2 levels result in enhanced warming of the earth”
And that is the point nobody has proved to my satisfaction. All we have are “models” created by people who already wanted to show this fact.
We have no indication that CO2 has added any appreciable amount of warming to Earth. And you have the problem of diminishing return. If you get a certain amount of warming when you add 100ppm of CO2, you get significantly LESS warming when you add the next 100ppm. The response is not linear.
Also I believe the models are completely bogus because they predict a hot spot in the middle of the atmosphere. You can’t do that in real life because they minute you warm air in a given location, it wants to rise and it rises above more of the CO2 in so doing and radiates any heat it gained into space. So an increase in CO2 would maybe increase convection but none of the models take convection into account. They seem to depend on a static and infinitely “deep” atmosphere.
The models aren’t based on reality.
crosspatch
December 21, 2008 1:50 pm
Overall, I agree with the elder Pielke. We *are* causing warming but not in the way that Hansen would have you believe. Most measured warming is due to local land use changes. And I don’t mean to imply I think it can be ignored but I believe we are focusing on the wrong thing.
When we cut down forest to build housing developments, turn the landscape from a shady green to a barren black (roofs, roads, parking lots) and fill it with a gazillion radiant heaters (cars sitting in the sun, etc) we do change the local temperature and precipitation patterns. Taken together in large urban regions such as the area between Washington and Boston, it can have a large regional impact.
Replacing millions of acres of natural grassland with plowed fields changes things too, as does irrigating millions more acres out west. Climate can very well change due to human activities but I believe it is less about the cars we drive and the electricity we generate than it is the forests we cut and the land we irrigate and the pavement we lay. Increasing albedo by simply changing the color of roofs and pavements, shading areas with trees, can go a lot further in reducing local climate changes due to human activity. Changing the amount of CO2 isn’t going to amount to any change, really, because even if every single human being on the planet were to perish today, it would reduce global CO2 emissions by about 3%.
PeteM
December 21, 2008 1:54 pm
deadwood (13:33:02) :
You have missed the point – Smokey seemed to suggest that distance from Sun was a factor to explain differences in Earth Mars and Venus .
The information I provided shows that is not always a dominant factor .
Venus is suffering from a strong green house effect (http://en.wikipedia.org/wiki/Venus)
Mars doesn’t have a thick enough atmosphere to escape most of the implications of its distance from the sun .
JimB
December 21, 2008 1:59 pm
Anyone have the total world supply of coal numbers at their fingertips?
I thought I read somewhere that at present consumption rates, there was enough coal in the U.S. alone to last 1,000yrs. I’m sure that China and Russia have some deposits as well…
Doesn’t Hansen’s preso state that if we burn “ALL the coal”?
JimB
Pete M:
To answer your question: yes, the proximity to the Sun is the dominant cause of the temperature differences between planets. Atmosphere is a secondary cause. Note that Jupiter, Saturn, Uranus, and Neptune — all gas giants with extremely thick atmospheres — become progressively colder as their distance from the Sun increases.
Your Mercury example has unique problems because Mercury’s day and year are the same, and Mercury has essentially no atmosphere. Your implication that the day side and night side should be averaged is incorrect.
So is the comparison with Venus, which has an atmosphere that is about 93 times denser than Earth’s atmosphere. It is laden with sulfuric acid, and it is completely covered with clouds. The atmosphere of Venus retains heat, but that is where any similarity ends.
Mars has a thin atmosphere consisting of more than 95% CO2. Yet the average temperature is below -80 degrees F. If CO2 were the scary greenhouse gas that AGW proponents believe it is, then Mars, with 95%+ CO2 [compared with Earth’s tiny .038] would have an average temperature greater than eighty degrees below zero, despite its thin atmosphere. But as we now understand, the heat retention of CO2 begins to fall off logarithmically after the first 20 ppmv. So Mars remains a very cold place, and 95% CO2 does not make a difference.
I understand that you’re avoiding my original point, which is that Hansen never mentions the close proximity of Venus to the Sun, as compared with the Earth’s distance. He simply points to Venus and says, “Runaway global warming!!” Why do you think he neglected to mention the basic fact that Venus is much closer to the Sun? Is it because he doesn’t want people to see the gaping hole in his conjecture?
More to the point: why is Hansen so afraid to debate his beliefs?
Bill Illis
December 21, 2008 2:00 pm
To foinavon
“T = (3.0/log(2))*(log(C))-9.39
where C is the CO2 concentration.”
is not a correct representation of the theory.
On page 8 of this paper by Raymond Pierrehumbert (a RealClimate contributor) http://geosci.uchicago.edu/~rtp1/papers/CaltechWater.pdf
“Eliminating the 50W/m2 of tropical CO2 greenhouse effect would drop the tropical temperature by about 25 K, once amplified by water vapor feedback.”
Hi,
Forgive OT but I don’t know the protocol for posting stuff like this:
I still would like Anthony or somebody to discuss the week or so oddity on the AMSR-E Sea Ice Extent chart. Unlike the other 5-6 years on the chart,2008 is now going sideways for the last week or so. Anna noted that thereis vulcanism in the region. Is there anybody talking about this, since it would seem to be a pretty big phenomenon to totally stop ice formation for over a week in the Artic, especially given the temperatures in the region as we speak: -18 degrees F at the North Pole
Grant
DailyKos reports on: Dr. James Hansen: “How do we make them understand how serious this is?” and gives links to other similar 2008 presentations.
The Dark and Bright Sides of Global Warming James Hansen August 13, 2008 YouTube
The Threat to the Planet: Dark & Bright Sides of Global Warming PDF
Jim Hansen, 3 October 2007, presented at conference: Heating Up the Energy Debate, Gustavus Adolphus College, St. Peter, Minnesota
What Hansen critically fails to realize is that liquid fuel is critical to our civilization – and his job. The looking decline in global petroleum production (“Peak Oil”) will enforce rapid reductions in available liquid fuels to fuel importing countries like the US. See:
Robert L. Hirsch The Inevitable Peaking of World Oil Production
Peaking of world oil production: recent Forecasts
US Department of Energy/National Energy Technology Lab., NETL-2007/1263 |
year = 2007, February 5, (The “Hirsch report”), and
Mitigation of maximum world oil production: Shortage scenarios Vol 36 # 2, Feb. 2008, 881-889
Our critical issue is not whether the ocean will warm 1 or 1.5 feet, but whether we will have the fuel to run tractors, trucks and to drive to work.
Note especially the World Export Model. Khebab, Graphoilogy, especially slides 16 and 17.
We can convert oil sands and coal to fuel. Sasol of South Africa has successfully been producing oil from coal since 1955.
I would like to see how Hansen proposes to run cars or planes on sequestered CO2. It is our future and our children’s that Hansen is unwittingly destroying in his zeal. Obama’s buying into Hansen’s perspective means much worse economic times ahead in that the US will be even more unprepared for operating on 75% less fuel than we currently use!
Here’s one of my favorite Hansen charts.
http://pubs.giss.nasa.gov/abstracts/1974/Lacis_Hansen_1.html
pg 119 shows solar energy vs wavelength in w/m
it also shows dark bands corresponding to absorption by (O2, O3, CO2, H2O)
CO2 appears to only effect low energy wavelengths.
But water vapor on the other hand….
So what happend to “If it looks to good to be true than it probably is ?”
Does he really think that the debate will be over now that he has nailed it? This is pure politics, and he knows it, its all or nothing now.
Just reading the deep ocean response time section of the presentation (of interest to me) and I can’t believe all the “if, then” “on the other hand, if, then ..” over and over again.
It does say most of the models predict it will take well over 1,000 years before the oceans fully adjust to the surface temperature.
Then there is no answer to the question of if it take the oceans 1,000 years to adjust (or in other words, 1,000 years to absorb heat from the surface) what does that do to the surface temperature response time – does it also take over 1,000 years – no answer to that important question – just more “aerosols are masking the warming which has occurred.”
It’s worth pointing out the essential fallacies represented in the two graphs presented in Anthony’s introductory post:
(i) the Illis temp vs [CO2] graph of Bill Illes (who he?) is very misleading since it is dominated by the very large temperature changes occurring over the very low [CO2] ranges (0-50 ppm) never experienced on earth.
It’s easy for anyone with the most basic graphing program (e.g. Excel) to see this for themselves.
You can construct essentially the same graph presented by Anthony (Illes) using the equation:
T = (3.0/log(2))*(log(C))-9.39
where C is the CO2 concentration.
So set up a column of X values ranging from 2-3000 ppm. This is C the atmospheric CO2 concentration
In the above equation 3.0 is the climate sensitivity, the log(2) value refers to the fact that this is the temperature increase upon doubling, the log (C) indicates the logarithmic relationship between temperature rise and change in CO2 concentration, and the 9.39 “normalises” the earth’s temperature to 15 oC at at pre-industrial CO2 concentration (280 ppm).
If you then expand the data to observe the relevant bits; i.e. CO2 concentration between 280 ppm and 1000 ppm (to give the extreme value that might be realized in the next 150 years if we didn’t address this problem at all) or 3000 ppm that might be realized under the Hansen scenario of burning all of the coal and tar shale, you can see that very dramatic temperature rise will accrue (and that’s without factoring in other potentially large feedbacks like recruiting all of the methane clathrates in the deep oceans).
(ii) The “Scotese” “graph” is nonsense. Where has it come from? It bears no relation to our understanding of the earth’s temperature and atmospheric CO2 levels in the deep past. I think we all know, for example, that the earth’s temperature hasn’t drifted steadily downwards from ~22 oC 25 million years ago to 12 oC now! And are we really supposed to believe that the earth’s temperature “sat” at a rock-steady 22 oC for many 10’s of millions of years in the past? I think not, and that’s certainly not what the science shows.
..oh well….
Alternative views (From New Scientist)
http://www.newscientist.com/commenting/browse?id=dn16292&page=6
The Consensus Is Fake – Scientists Do Not Agree
Fri Dec 19 15:59:50 GMT 2008 by Benfranklin
I am a skeptic.Global warming has become a new religion. – Nobel Prize Winner for Physics, Ivar Giaever.
Since I am no longer affiliated with any organization nor receiving any funding, I can speak quite frankly.As a scientist I remain skeptical. – Atmospheric Scientist Dr. Joanne Simpson, the first woman in the world to receive a PhD in meteorology and formerly of NASA who has authored more than 190 studies and has been called among the most preeminent scientists of the last 100 years.
Warming fears are the worst scientific scandal in the history. When people come to know what the truth is, they will feel deceived by science and scientists. – UN IPCC Japanese Scientist Dr. Kiminori Itoh, an award-winning PhD environmental physical chemist.
The IPCC has actually become a closed circuit; it doesnt listen to others. It doesnt have open minds. I am really amazed that the Nobel Peace Prize has been given on scientifically incorrect conclusions by people who are not geologists,- Indian geologist Dr. Arun D. Ahluwalia at Punjab University and a board member of the UN-supported International Year of the Planet.
The models and forecasts of the UN IPCC “are incorrect because they only are based on mathematical models and presented results at scenarios that do not include, for example, solar activity. – Victor Manuel Velasco Herrera, a researcher at the Institute of Geophysics of the National Autonomous University of Mexico.
It is a blatant lie put forth in the media that makes it seem there is only a fringe of scientists who don buy into anthropogenic global warming. – U.S Government Atmospheric Scientist Stanley B. Goldenberg of the Hurricane Research Division of NOAA.
Even doubling or tripling the amount of carbon dioxide will virtually have little impact, as water vapour and water condensed on particles as clouds dominate the worldwide scene and always will. – Geoffrey G. Duffy a professor in the Department of Chemical and Materials Engineering of the University of Auckland, NZ.
After reading [UN IPCC chairman] Pachauri’s asinine comment [comparing skeptics to] Flat Earthers, it’s hard to remain quiet. – Climate statistician Dr. William M. Briggs, who specializes in the statistics of forecast evaluation, serves on the American Meteorological Society’s Probability and Statistics Committee and is an Associate Editor of Monthly Weather Review.
For how many years must the planet cool before we begin to understand that the planet is not warming? For how many years must cooling go on?” – Geologist Dr. David Gee the chairman of the science committee of the 2008 International Geological Congress who has authored 130 plus peer reviewed papers, and is currently at Uppsala University in Sweden.
Gore prompted me to start delving into the science again and I quickly found myself solidly in the skeptic camp Climate models can at best be useful for explaining climate changes after the fact. – Meteorologist Hajo Smit of Holland, who reversed his belief in man-made warming to become a skeptic, is a former member of the Dutch UN IPCC committee.
Many [scientists] are now searching for a way to back out quietly (from promoting warming fears), without having their professional careers ruined. – Atmospheric physicist James A. Peden, formerly of the Space Research and Coordination Center in Pittsburgh.
Creating an ideology pegged to carbon dioxide is a dangerous nonsense The present alarm on climate change is an instrument of social control, a pretext for major businesses and political battle. It became an ideology, which is concerning.- Environmental Scientist Professor Delgado Domingos of Portugal, the founder of the Numerical Weather Forecast group, has more than 150 published articles.
CO2 emissions make absolutely no difference one way or another. Every scientist knows this, but it doesn pay to say so Global warming, as a political vehicle, keeps Europeans in the driver seat and developing nations walking barefoot. – Dr. Takeda Kunihiko, vice-chancellor of the Institute of Science and Technology Research at Chubu University in Japan.
The [global warming] scaremongering has its justification in the fact that it is something that generates funds. – Award-winning Paleontologist Dr. Eduardo Tonni, of the Committee for Scientific Research in Buenos Aires and head of the Paleontology Department at the University of La Plata.
Slightly off topic…having a little but uncertain hope is worse than having no hope at all. Yet New Scientist, in an article on-line, first says we have reached a tipping point of no return and then says, well, there may yet be a little hope for the Arctic (summer) ice after all. It’s a very confusing article, all based on those infamous oh-so-reliable computerized models.
As you can see from the link, the headline is: Arctic melt 20 years ahead of models. The question nobody seems to be asking, however, is: if this is so, why are the models so incorrect? Could it be that, one way or the other, we really still don’t understand how our complicated planetary climate system works? Like the ending of that tootsie pop commercial says, “the world may never know.”
http://www.newscientist.com/article/dn16307-arctic-melt-20-years-ahead-of-climate-models.html
Ed Scott quotes Holdren:
“THE FEW climate-change “skeptics” with any sort of scientific credentials continue to receive attention in the media out of all proportion to their numbers, their qualifications, or the merit of their arguments. And this muddying of the waters of public discourse is being magnified by the parroting of these arguments by a larger population of amateur skeptics with no scientific credentials at all.”
I do not profess to have any grounding in specialist subjects related to AGW but I studied Geography and Geology and Meteorology in some depth at College to degree level. Ergo I am an ‘amateur’, the paranoia with which this site is vilified is interesting, can we not have serious debate? What are the pro man-made GW warming scientists worried about??
If you do not have significant number of letters after your name, then your opinion does not count! Why is this? – can it be that if you do not believe, and are uneducated then it follows that you are not worthy of joining the debate.
Some of us are just saying, “hang on a minute let us test the theory before we commit to these ideas” That surely is the essence of Scientific debate and whether or not you are qualified, this is not relevant. The jury is still out and because a lot of people think one thing, they are not always necessarily correct, just ask Gallileo.
Tom.
Hansen cites CO2 in some 16 pages, but only mentions water relating to melting glaciers or ocean level rise.
Hansen fails to clearly show that H2O is 80% of greenhouse gas while CO2 only 20%. Furthermore, we know the least about H2O, especially the precipitation and the water heat conduction mechanisms, especially below the troposphere.
Anthony,
Could we then call Steve McIntyre the “Sauron of the Skeptics”? A little Lord of the Rings humor there, but fittingly appropriate. Characters in LOTR often use “the Enemy” or “the Unnamed One” when referring to Sauron. Steve “Sauron” McIntyre? Not a bad monicker.
REPLY: I don’t think he’d appreciate the title, but I could be wrong. – Anthony
Ben,
When you refer to ice core data; just what “data” do you mean ? I would suggest that there is NO ice core data that is more famous world wide, tha the two graphs in Al gore’s “an Inconvenient Truth (p 66/67), and that is simply purported Temperature Data, and purported CO2 data. My understanding is that the CO2 data is actual measured CO2 composition in the samples, and that the “Temperature Data” relies on an O16/O18 proxy; which I don’t claim to understand. how O16 and O18 can simply transmute into each other (or from something else solely as a function of atmospheric temperature is beyond my understanding of atomic Physics (which I once taught0, but that was way back at the start of the space age.
But I am constantly amazed at the ingenuity of scientists at sensing things remotely. My hat is off to Astronomers, who pretty much derive their entire science from the Electromagnetic spectrum for DC to Cosmetic Rays and beyond to unobservable parallel univerese, where any imaginable lwas of Physics can be found.
Now I know those “ice cores” yield a whole lot more substance that just temperature proxies, and CO2 concentrations, and I also know there is a whole lot of skepticism/ debate about just how reliabl;e that stuff is.
But regardless of doubts about the validity of these proxies; it seems to me, that the one thing you can probably count on with some level of credibility, is THE TIMING of whatever happens in those ice cores. They are very tree ring like in their Timing, although I never heard of one tree ring diffusing into otheres to scramble the data. But I generally believe the event timing; unless the lab technicians sometimes screw up.
And therein lies the crux in my mind. In Al gore’s book he deliberately separated those two graphs vertically for the purpose of hiding the true relative timing of CO2 events, and Temperature events.
Well OK he hasn’t had his day in court so maybe I shouldn’t accuse him of outright fraud; I mean it is also possible that he is just as dumb as a box of rocks, and didn’t realize that if he overlapped the curves, one could really see the relative timing of events; sort of what an 8th grade high school science student would do.
Well I have to admit that I have seen the same data printed in peer reviewed journals and other so-called Scientific publications; and actually I have NEVER ever see them overlapped by any author; but I don’t deny that some author/s may exist who have done that.
Bottom line is it is evidently irrefutable that the temperature changes precede the CO2 changes (that caused them) by intervals of from 500 -1500 years, with 800 years appaerntly yielding the highest correlation coefficient.
So regardless of how hokey other ice core evidence may or may not be (I’m not competent to judge that); I don’t se how you get past the usually fatal conclusion that we don’t like our causes happening 800 years after the effect that they cause.
I actually queried Spenser Weart on that point, in Physics Today for Jan 2005 (letters), and he basically changed the subject in his reply, and by e-mail declined to comment further.
Explain the relative timing “anomaly” to me and I’ll die happy.
There are some significant problems with ice cores that aren’t obvious. First of all, Southern Hemisphere ice going to present with a few problems. Antarctica is so huge (twice the size of Australia) and so cold and centered on the pole so it basically makes its own weather. The ice there has survived since long before we had the current cycles of glaciation in the Northern Hemisphere. Also, since it is already so cold there in winter, variations in global temperatures or Northern Hemisphere temperatures might not make that much difference at the South pole.
There really isn’t any analog to Greenland in the Southern Hemisphere where you would have a relatively large land mass with long standing ice. Tropical ice cores would be ideal but there is a major problem with them in that when we go into a Northern Hemisphere ice age, the climate becomes so dry in places like the Andes that the ice disappears for lack of precipitation. The oldest ice core I have been able to learn about from the Andes goes back only 20,000 years and then you hit bedrock. So when we were at glacial maximum in the Northern Hemisphere, the Andes were likely free of snow because of a lack of moisture to produce adequate snow to survive through sunny periods.
New Zealand Southern Alps would seem to be a good candidate but again, the ice doesn’t seem to go very far back in time, nothing found that I know of that goes back before the Holocene. So our ice core records are limited by the looking only at the local climate in Greenland and Antarctica which seem to have had very different local responses to global conditions. We can’t look at Antarctica cores and figure out what things are going to do in the Northern Hemisphere and we don’t have any Northern Hemisphere locations other than Greenland.
That leaves the Himalayas but so far cores seem to give conflicting results in some cases. We just don’t have enough samples from that region to be able to say much. I did find this interesting though:
So here we again show insolation (amount of sunshine) a major driving factor but also we see “the transition from warm to cold periods was abrupt”. Which again would argue against gradual orbital changes being the cause of these abrupt changes. Something else needs to “kick” the system into the other state and the orbital mechanics might be a hysteresis mechanism that keeps it in that state.
The hypothesis I am coming around to is that orbital changes cause a slow change in insolation. Our sun is a variable star. We sometimes have periods of low activity (Maunder, Dalton, etc) which seem to correspond to additional cooling. We also have ocean cycles that seem to be unrelated to these events but also cause some climate impact. When we get into a period of decreasing insolation due to gradual changes in orbit, it might be likely that a period of decreased solar activity might be enough to “kick” the system into a colder stable state. If the solar minimum happens while we are also in a “cold” ocean cycle, it might be even more likely to be a trigger that could switch the state of the system in an abrupt fashion.
Things would then go along until we get into a cycle of increasing solar insolation and have a period of increased solar output, maybe combined with a cycle of warmer ocean climate at the same time and it “kicks” the system into the other state.
This would also explain why we seem to “miss” some 40,000 year periods of opportunity when orbital conditions seem right to come out of the glaciation but don’t. Maybe you need all three conditions to be right. You need the right about of sunlight, the right general trend in sunlight, and be in the right cycle of things in ocean cycle. If we have increasing insolation, and an active sun but the Pacific is in a “cold” phase, it isn’t enough and things stay in the cold state until all three conditions line up again.
The abruptness of the change suggests that something or some combination of things act to trigger a phase change between two stable states. It also seems that the cold phase is the more stable of the two states as the climate seems to stay in that phase 90% of the time and is in the warm state only 10% of the time. Also, overall the glaciation periods have been getting longer meaning it seems to be getting even more stable in the cold state and that might be caused by gradual changes in ocean currents caused by tectonics. As the positions of things change, ocean currents change. We could well at some point get to a situation where the isthmus of Panama opens back up again, we get more equatorial mixing, and the system goes more stable in the warm state as it apparently was some 3-5 million years ago.
But I am just guessing.
@Smokey (11:24:08) : On your point
“After reading Hansen’s comparison of the Earth and Venus, I notice that he made no mention of the fact that Venus is much closer to the Sun than the Earth is. Or that Mars’ atmosphere is mostly CO2, and Mars is freezing cold.
….. ”
(a) I’m not sure if you are suggesting that position from the sun is the dominant reason for the the temperature difference between Venus , Earth and Mars .
Mercury is much closer to the Sun (58 million Km) than Venus (108 million km)
Mercury has a temperature of that varies between about 430 C and -180 C. Venus has a temperature of about 450 C with not much difference between night side and sun side.
This can be explained by a run away greenhouse effect on Venus
(http://en.wikipedia.org/wiki/Venus)
(b) Since atmosphere is important ( comparing Venus and Mercury) …why is Mars cooler . Its atmosphere is so thin (about 100th that of the Earth) that even though the CO2 content is hight ( 95%) there isn’t enough to cause a runaway greenhouse effect or mask the effect of its distance from the Sun .
(http://www-k12.atmos.washington.edu/k12/resources/mars_data-information/temperature_overview.html) . Although the CO2 content does appear to have some effect on Mars.
I can still access that image here:
http://earthobservatory.nasa.gov/IOTD/view.php?id=6502
It was NASA’s “Image of the Day”, pPosted April 27, 2006.
REPLY: Thanks for finding that, interesting to note the before and after images they cite. Big difference.
Anthony
It’s also curious when making the comparison to Venus, shouldn’t he mention Venus has no no planetary magnetic field? Because of that, the sun has stripped Venus’ atmosphere of most of the lighter gases, leaving an atmosphere of mostly the heavier CO2 and Nitrogen molecules.
If you are going to do science why not do it completely, why not do it in the open?
It’s as if he thinks no one knows what photosynthesis is. Come to think of it, I asked that very same question to a group of people (I won’t say who they really were) and not one in the crowd knew what it was. So obviously they didn’t have a clue what would happen if we were able and reduced the CO2 in the atmosphere to zero.
George Smith:
18O/16O in H2O in ice cores:
This pretty much represents the effect of distillation. It takes more thermal energy to vapourize 18O water than 16O water, and during glacial periods with colder seas, the water vapour is depeleted in 18O water as a result. And as the vapour travels to the polar regions there is anadditional tendency for any 18O water to condense our before 16O water. So when polar precipitation (snow!) occurs, the water is more depleted in 18O(H2O) relative to 16O(H2O), and this can be measured in the ice cores using mass spectrometry.
Timing of CO2 and temperature in ice cores:
Yes, the temperature variations precede the CO2 variations throughout much of the ice core depths. That rresults from the fact that the temperature variations during these events were initiated by insolation changes resulting from the cyclic variations in the earth’s orbital properties. According to the Illes graph that is shown in the introductory article of this thread, rising atmospheric CO2 levels result in warming, and this equates to around 3 oC of warming per doubling of atmospheric CO2. So during ice age cycles the raised atmospheric CO2 concentrations from around 180 ppm to 270 ppm during a glacial to interglacial transition contributed a bit under 2 oC of warming to the total warming transition.
Remember that during the ice age transitions these phenomena were slow, slow slow! So the last glacial to interglacial transition from around 15,000 to 10,000 years ago saw atmospheric CO2 levels rise by around 90 ppm over 5000 years. That’s less than 2 ppm per 100 years averaged ove rthe transition.
Atmospheric CO2 levels are rising over 100 times faster now (of the order of 2.5 ppm per year).
The essential point is that however atmospheric CO2 levels rise (a result of orbital-induced insolation changes during ice age cycles, or direct pumping into the atmosphere on a truly humungous scale now), the enhanced CO2 levels result in enhanced warming of the earth (near 3 oC of warming per dubling of atmospheric CO2 according to a whole load of analyses).
PeteM:
Did you even read Kasting’s 1988 paper where he uses the term “runaway greenhouse” occurs? Clearly not. He is specifically linking this term to solar activity during the early stages of planetary evolution causing all the water vapor to blow away into space.
The water it seems, in his one-dimensional atmospheric model, acted as a negative feedback untill it dissipated into space.
Try again Pete, but this time follow-up on your “proof”. Don’t just read the buzz words.
Is it possible that Hansen believes nobody will bother to check on his work? Perhaps he believes people will blindly accept everything he says as fact, instead of wishful-thinking-based opinion?
“the enhanced CO2 levels result in enhanced warming of the earth”
And that is the point nobody has proved to my satisfaction. All we have are “models” created by people who already wanted to show this fact.
We have no indication that CO2 has added any appreciable amount of warming to Earth. And you have the problem of diminishing return. If you get a certain amount of warming when you add 100ppm of CO2, you get significantly LESS warming when you add the next 100ppm. The response is not linear.
Also I believe the models are completely bogus because they predict a hot spot in the middle of the atmosphere. You can’t do that in real life because they minute you warm air in a given location, it wants to rise and it rises above more of the CO2 in so doing and radiates any heat it gained into space. So an increase in CO2 would maybe increase convection but none of the models take convection into account. They seem to depend on a static and infinitely “deep” atmosphere.
The models aren’t based on reality.
Overall, I agree with the elder Pielke. We *are* causing warming but not in the way that Hansen would have you believe. Most measured warming is due to local land use changes. And I don’t mean to imply I think it can be ignored but I believe we are focusing on the wrong thing.
When we cut down forest to build housing developments, turn the landscape from a shady green to a barren black (roofs, roads, parking lots) and fill it with a gazillion radiant heaters (cars sitting in the sun, etc) we do change the local temperature and precipitation patterns. Taken together in large urban regions such as the area between Washington and Boston, it can have a large regional impact.
Replacing millions of acres of natural grassland with plowed fields changes things too, as does irrigating millions more acres out west. Climate can very well change due to human activities but I believe it is less about the cars we drive and the electricity we generate than it is the forests we cut and the land we irrigate and the pavement we lay. Increasing albedo by simply changing the color of roofs and pavements, shading areas with trees, can go a lot further in reducing local climate changes due to human activity. Changing the amount of CO2 isn’t going to amount to any change, really, because even if every single human being on the planet were to perish today, it would reduce global CO2 emissions by about 3%.
deadwood (13:33:02) :
You have missed the point – Smokey seemed to suggest that distance from Sun was a factor to explain differences in Earth Mars and Venus .
The information I provided shows that is not always a dominant factor .
Venus is suffering from a strong green house effect (http://en.wikipedia.org/wiki/Venus)
Mars doesn’t have a thick enough atmosphere to escape most of the implications of its distance from the sun .
Anyone have the total world supply of coal numbers at their fingertips?
I thought I read somewhere that at present consumption rates, there was enough coal in the U.S. alone to last 1,000yrs. I’m sure that China and Russia have some deposits as well…
Doesn’t Hansen’s preso state that if we burn “ALL the coal”?
JimB
Pete M:
To answer your question: yes, the proximity to the Sun is the dominant cause of the temperature differences between planets. Atmosphere is a secondary cause. Note that Jupiter, Saturn, Uranus, and Neptune — all gas giants with extremely thick atmospheres — become progressively colder as their distance from the Sun increases.
Your Mercury example has unique problems because Mercury’s day and year are the same, and Mercury has essentially no atmosphere. Your implication that the day side and night side should be averaged is incorrect.
So is the comparison with Venus, which has an atmosphere that is about 93 times denser than Earth’s atmosphere. It is laden with sulfuric acid, and it is completely covered with clouds. The atmosphere of Venus retains heat, but that is where any similarity ends.
Mars has a thin atmosphere consisting of more than 95% CO2. Yet the average temperature is below -80 degrees F. If CO2 were the scary greenhouse gas that AGW proponents believe it is, then Mars, with 95%+ CO2 [compared with Earth’s tiny .038] would have an average temperature greater than eighty degrees below zero, despite its thin atmosphere. But as we now understand, the heat retention of CO2 begins to fall off logarithmically after the first 20 ppmv. So Mars remains a very cold place, and 95% CO2 does not make a difference.
I understand that you’re avoiding my original point, which is that Hansen never mentions the close proximity of Venus to the Sun, as compared with the Earth’s distance. He simply points to Venus and says, “Runaway global warming!!” Why do you think he neglected to mention the basic fact that Venus is much closer to the Sun? Is it because he doesn’t want people to see the gaping hole in his conjecture?
More to the point: why is Hansen so afraid to debate his beliefs?
To foinavon
“T = (3.0/log(2))*(log(C))-9.39
where C is the CO2 concentration.”
is not a correct representation of the theory.
On page 8 of this paper by Raymond Pierrehumbert (a RealClimate contributor)
http://geosci.uchicago.edu/~rtp1/papers/CaltechWater.pdf
“Eliminating the 50W/m2 of tropical CO2 greenhouse effect would drop the tropical temperature by about 25 K, once amplified by water vapor feedback.”