First open thread of 2012, so perhaps some discussion of the highlights and lowlights of 2011 are in order? Top 5 lists welcome…
Reader Interactions
361 Responses to "Unforced variations: Jan 2012"
Steve Metzlersays
Thanks for the play-by-play, MARodger. But I re-read the whole thread from the start before reading your last post, and found out where my brain had picked up on the Dan H./co2science connection:
#45 Hank Roberts:
We don’t know if Dan is misreading after finding his own sources or if he’s copypasting from some place like CO2Science that supplies cherries pre-spun.
So it was a mistaken connection, and I was about to apologise… but now it looks like #97 Craig Nazor has caught Dan out. His true colours are shining through in that change.org thread. Thanks for that, Craig. Explains a lot.
For those who’ve paid the minimal AGU annual dues, the AGU member newspaper EOS has a couple of excellent articles on misconceptions and how to teach science by correcting them.
These articles address basic misunderstandings, including denial PR — the same notions often rebunked here — as misconceptions, fundamentally wrong ideas about how the world works; teachers need to understand and address those directly.
@ Pete D #11 Thanks for the Hansen link – good stuff! Hansen said (http://www.columbia.edu/~jeh1/mailings/2011/20111110_NewClimateDice.pdf):
“The climate dice are now loaded to a degree that the perceptive person (old enough to remember the climate of 1951-1980) should be able to recognize the existence of climate change.”
I happen to have been thinking about the membership of that group of people for a while and it is smaller than we might at first think. A quick estimate goes like this:
Age group has to be 40+, since anyone under ten in the early 1980s won’t remember the old norms, and that rules out more than 50% of the world’s population and perhaps even more than 50% of the world’s voters.
But also, those people have to have been living in the same general area for 40+ years, or have returned to it after some time away, because no-one in California will say, “It wasn’t like this when I was a kid,” if they grew up in Normandy, Quebec or even Virginia. How many of us are that stable? 50%?
But also, the closer we live to nature, the more likely we are to notice its changes – but more and more of us are urbanised. How many of the 50% of 50% are therefore likely to qualify as “perceptive”? Less than 50% in the West, certainly; perhaps more than 50% in less urbanised countries.
That leaves less than 10% of the world’s population in a position to recognise, from personal observation, climate change. And (unfortunately for the debate) most of those 10% are the rural poor of developing nations, the most frequent victims of climate change not the opinion-makers of industrialised nations.
“Canada’s message: The world and its climate be damned”. That headline on Jeffrey Simpson’s scathing commentary on Canada’s pending formal withdrawal from the Kyoto Protocol said it all. …
But I want to turn today to an analysis of the Conservative government’s putative alternative to Kyoto, namely the 2009 Copenhagen agreement, as well as the GHG reduction plans put forth in 2008 by Canada and the province Alberta (home to the oil sands and Conservative Prime Minister Stephen Harper). That analysis confirms the contention of Jeffrey Simpson and others that the government of Canada is “mocking” the 2020 target agreed to only two years ago; the promised 17% reduction in annual GHG emissions (relative to 2005) is already out of reach. A big reason for this is an Alberta target (itself very unlikely to be met) that calls for a rise in GHG emissions until 2020. Not only that, but Alberta’s 2050 target, predicated on massive expansion of oil sands operations, is only 14% below 2005 levels, and sets Canada on a path that can not possibly be reconciled with the Harper government’s own stated long-term target, let alone any reasonable goal compatible with Canada’s responsibilities.
Humanity’s epitaph:
1. Not Dead. Resting. (with apologies to Monty Python)
2. I told you we should have evolved faster.
3. We’ve all gone to Hell – it’s cooler there.
4. The meek inherited the Earth they deserved.
5. I hear Venus is pleasant at this time of year.
6. So long, and thanks for all the fossils.
7. So much plant food, so few plants …
8. Look on our works, Ye mighty, and despair.
@Hank Roberts#89
Thanks for the link to scholar.google.com. Not being a scientist, I have never stumbled on it before. Looks like a good way for an amateur to ‘get to the source’ and I will be glad to use it.
#106–Sadly, not a surprise. IMO, it’s been pretty clear for quite a while that the Harper government has a “good-faith” quotient on this issue that is indistinguishable from zero. They pay lip service to the importance of fighting climate change–‘lip service’ includes a few millions for arguably related measures–but play a role that is functionally highly obstructive. Just as sad, they are in this not that different from the preceding Liberal governments.
And this despite a public that regularly reports itself to be relatively convinced of the seriousness of the problem.
Ron R.says
Ok, so just to ask the obvious question (someone has to): building on the FACE experiments and Hank’s comments about the fertilizer addition of nitrogen to the biosphere, if we were to, in a massive geoengineering experiment, artificially add N to the world’s forests (and possibly P & K), hopefully in an easy to breakdown, organic form, being careful to keep it away from waterways, might that allow those plant species within to increase their carbon intake and thus lower atmospheric CO2?
I really hesitate to mention something like this as there always seems to be serious and unacceptable side effects to our grandiose tinkering. Maybe it’s already been thought of and dismissed (like the ocean fertilization plan was) and I just missed the boat. Again.
JCHsays
Surely in urban areas trees are exposed to higher levels of atmospheric CO2, and to nitrogen, etc. from lawn fertilizers. Are urban trees significantly larger?
As Eli pointed out recently, Su et al. suggest that our nitrogen oxide pollution has so far had the collateral benefit that “the oxidative capacity of the atmosphere has remained constant ….”
” …. water aerosols where nitrogen dioxide has dissolved
H2O(aq) + 2 NO2(aq)= HNO3(aq) + HONO (g)
HONO is THE source of HO in the atmosphere ….”
…
“… and we know that agriculture is increasingly acidifying and fertilizing soils which is degrading water quality and increasing eutrophication. It may also have maintained the oxidative capacity of the atmosphere, leaving us lagomorphs with the choice of dirty air or dirty water ….”
——-
As you said, geoengineering. It’s the sort of thing only a sociopath would have funded, fifty years ago.
Well worth $20.
Membership is by calendar year.
This is the time to join, to get all the 2010 info.
That gets you abstracts and news (science journals cost more, but public libraries get them — if you know what to ask for. Basic membership info helps know what to ask).
Interesting question. Problem is that urban areas tend to want to keep trees to and of a certain height. And nitrogen fertilizers are not evenly spread, just usually on grass and crops (though trees could probably pick some up in the water table).
Ron R.says
Hmmm.
“There are also implications for global change models, which are beginning to include nitrogen availability as a factor affecting the response of plants to increasing atmospheric carbon dioxide concentrations,” said Turner. “Most models assume that higher nitrogen equals more plant growth, which would remove carbon from the atmosphere and offset future warming. However a challenge for the models is that there is no evidence that trees are growing faster in Panama, despite the long-term increases in nitrogen deposition and atmospheric carbon dioxide.”
Houlton noted that nitrogen is becoming increasingly important in climate-change studies and researchers have begun to incorporate nitrogen in their climate-change models. Some models indicate that the nutrient could cause an additional increase in global temperatures of up to one degree Celsius (1.8 degrees Fahrenheit) by 2010, as it limits the amount of carbon dioxide that plants around the world can extract from the atmosphere. If more nitrogen is available than predicted from the traditional nitrogen-cycling pathways, as the UC Davis study suggests, it could lead to more carbon storage on land and less carbon remaining in the atmosphere.
Jumping back, I quoted from
Journal and Proceedings of the Royal Society of New South Wales, vol. 144, nos. 3&4, pp. 50-57.Page 4, ISSN 0035-9173/11/020050-8
Science advice and policy making
Robert M. May OM AC FRS FRSN
Lord May of Oxford
Zoology Department, Oxford University, Oxford OX1 3PS, UK
some of this bit:
“more than half of all the atoms of nitrogen and of
phosphorus in green plant material that grew
last year came from artificial fertilisers, rather
than the natural biogeochemical cycles”
The paper attributes that to
Conway, G.(1997) The Doubly Green Revolution;
Penguin Books, London, UK
I’m curious whether the “green plant material” is terrestrial or includes eutrophication; looking for more info on this rather astonishing number for nitrogen — though we’ve been making nitrogen fertilizer out of air for a long while; there’s no artificial source for phosphorous fertilizer, which is expected to be scarce rather soon.
Rick Brownsays
Ron R. @many. You might want to read
Chmura et al. 2011. Forest responses to climate change in the northwestern United States: Ecophysiological foundations for adaptive management. Forest Ecology and Management 261:1121-1142. http://www.fs.fed.us/pnw/pubs/journals/pnw_2011chmura001.pdf
Conclusion of section on increased CO2:
To summarize, increases in atmospheric [CO2] should be somewhat favorable for trees and forests, resulting in increased growth, vigor, regeneration, and survival. However, increases in [CO2] will
not occur in isolation, but are expected to occur in combination with warmer temperatures and increased drought stress. Elevated [CO2] enhances WUE at the leaf level, but this is unlikely to translate into large increases at the tree or stand levels, or substantially increase drought hardiness. Consequently, the adverse effects of these other climatic changes will probably be much larger than the positive effects of higher [CO2]. Therefore, rather than focusing on the direct effects of CO2 alone, it is important to understand whether elevated [CO2] will mitigate the adverse effects of other climatic stressors. Unfortunately, we have only limited information on these interactions, and how they might differ by developmental stage or among species or functional groups. Ultimately, these interactions must be realistically integrated into physiological process models to confidently predict ecosystem responses to climate change.
Craig Nazorsays
Ron R.,
I am no scientist, but I have a bit of experience with horticulture, and here is my opinion concerning the FACE experiment.
It was an experiment done on ONE species of angiosperm tree – the American sweet gum, Liquidambar styraciflua. This tree is a primitive angiosperm. To think that ALL other species of trees will behave the same as this one, and then plan a fix for anthropogenic global climate change (AGCC) based on the reaction of one species of tree is not advisable, to say the least.
Also, as other posters have pointed out, CO2 levels are not the only limiting factor affecting plant growth. There are numerous experiments that show that, even if CO2 levels are high, plants cannot always take advantage of this because of limitations of water, nitrogen, and/or the availability of many trace elements. Nitrogen, in particular, is complicated when it comes to plants. Some species (with the aid of cyanobacteria) can essentially suck nitrogen out of the air. Most are not so lucky, and have to rely on all kinds of symbiotic relationships in the nitrogen cycle, which can be sensitive to all kinds of factors, including human tampering. AGCC could wreck havoc with any one of, or even all, of these plant needs. And different species out-competing each other for CO2 uptake and increased growth will drastically change whole ecosystems, with unknown consequences to carbon sequestration.
I would not rely on some kind of geo-engineering with the ability of a species of plant to sequester CO2 to save us from the worst effects of AGCC.
Dan H.says
I would like to take this time to apologize to Hank for my statement about not linking to co2science. It appears that I did copy a link from co2science that was posted here last year (response #43).
I was unaware that the link was to co2science as opening the link only reveals the letter, and does not lead on to the website. However, the evidence shows that I did post a link to co2science, so I will recant my statement. Sorry, Hank.
GSWsays
Question for Gavin: As it is January, will there be another “How are the models doing” post this year?
[Response: Yes. I’m waiting for some last minute updates (though the basic picture will not be different from last year, but I may have some new CMIP5 results to throw in the mix). – gavin]
Johnsays
Mr. Nazor @ 123
Summarized by Liebig’s Law of the Minimum
GSWsays
@Gavin
Cheers!
Dan H.says
Craig,
The FACE experiments included aspens, birch, pine, poplars, and other hardwood trees also. The sweetgums were from the Oak Ridge tests (ORNL), which were the only species which showed a N-limitation.
Yes, CO2 is but one limiter of plant growth. In areas where species are water-limited, temperature-limited, N-limited (such as the sweetgums mentioned previously), or other nutrient-limited, increases in atmospheric CO2 will have minimal effects.
Ray Ladburysays
Dan H.
And of course we know climate change will also increase drought–implying by your own admission that atmospheric CO2 will have minimal fertilizing effects.
Dan H. misrepresents the paper _again_. They say they don’t know and suggest several possible explanations; Dan phrases his comment as though he knows the answer and it’s the one convenient for his talking point.
He’s using debate tactics to mislead, over and over.
“An unanswered question has been why the negative feedback through the N cycle developed in ORNL-FACE and not in other forested FACE experiments. There may be a fundamental difference in the biology of the various systems, such as a reliance on ectomycorrhizae as opposed to arbuscular mycorrhizae (Drake et al. 2011). Another possibility is that downregulation of forest growth response would have occurred across all experiments given enough time. Tissue turnover times are faster in the ORNL sweetgum stand than in the Duke-FACE pine stand, which may have accelerated the development of N limitation….”
Ron R.says
Hank Roberts — 8 Jan 2012 @ 3:09 PM
Thanks for that Hank.
Craig Nazor — 9 Jan 2012 @ 3:45 AM
Also, as other posters have pointed out, CO2 levels are not the only limiting factor affecting plant growth. There are numerous experiments that show that, even if CO2 levels are high, plants cannot always take advantage of this because of limitations of water, nitrogen, and/or the availability of many trace elements. Nitrogen, in particular, is complicated when it comes to plants.
Hi Craig. Read my posts and you’ll find that I agree with you.
Somebody else take on chasing down stuff for a while, eh?
I’m just tired of it.
I want to learn about climate here from the scientists.
Checking every damn thing from consistently unreliable sources does lead to good information, but only on the parts of the science they misstate. That’s a poor sample of the breadth of the science I want to learn.
I’m increasingly fond of Deltoid’s approach to keeping conversations alive:
Jonas Thread : Deltoid
By popular request, here is the Jonas thread. All comments by Jonas and replies to his comments …
Tim Curtin thread : Deltoid
By request here is a new thread for folks to argue with Tim Curtin. Tim, this is the only thread you are allowed to post on….
scienceblogs.com/deltoid/2009/03/tim_curtin_thread.php
Dan H.says
Hank,
I believe you just confirmed my statement that only the ORNL-FACE experiments showed N-limitations.
“In this document, I have bundled, updated, and expanded my series of essays debunking the congressional testimony of Dr. John Everett regarding the environmental chemistry of carbon dioxide.
… A part of my John Everett series – read more: 0/I – II.0 – II.5 – II.75 – III.0 – III.3 – IV.0 – IV.4 – IV.8 – V – VII – VIII – Full Report
Dan, they tried to falsify a number of ideas. You point to one such result without context, and claim literal truth, making it sound like a generally applicable statement.
You’re debating. I’m not.
Read context, footnotes, citing papers.
Plonk.
Dan H.says
Hank,
Who tried to falsify a number of ideas? Are you claiming entire FACE or just ORNL? Please elaborate, otherwise the remainder of your post is lost.
Dan, you know what a hypothesis is?
You know what a scientist does with a hypothesis?
You know where in the FACE paper you’ve been citing the authors list a number of hypotheses, and discuss each one, saying it was accepted, or rejected, or something more complex?
Stirring the methane pot has gotten boring, how about something more intriguing – like the magnetosphere. David Suzuki’s Nature of Things had a program on the overdue flip that made passing reference to it’s possible influence on [or correlation with] climate, even had a cameo appearance by Svensmark. Has there been any work with the ACE data relating the earths magnetic field [moving/weakening] to climate?
[how the heck does CAPTCHA expect us to reproduce upside down words and arcane symbols??]
[Response: If the Earth’s magnetic field had a significant impact on climate (via any mechanism), you’d see something associated with the Laschamp event (40,000 years ago), or any of the magnetic reversal boundaries (e.g. the Brunes Matayama – 700,000 years ago). You don’t. – gavin]
t_p_hamiltonsays
[Response: If the Earth’s magnetic field had a significant impact on climate (via any mechanism), you’d see something associated with the Laschamp event (40,000 years ago), or any of the magnetic reversal boundaries (e.g. the Brunes Matayama – 700,000 years ago). You don’t. – gavin]
This also argues against cosmic ray intensity significantly affecting climate, doesn’t it, since cosmic rays intensity depends on the earth’s magnetic field. Maybe useful for an article if there is another denialist push of a “cosmic rays cause climate change” article.
[Response: This is already well known, see Wagner et al (2001) for instance. – gavin]
vukcevicsays
[Response: If the Earth’s magnetic field had a significant impact on climate (via any mechanism), you’d see something associated with the Laschamp event (40,000 years ago), or any of the magnetic reversal boundaries (e.g. the Brunes Matayama – 700,000 years ago). You don’t. – gavin]
There are number of misconceptions about possible Earth’s magnetic field – temperature relationship. As far as I understand it, the Earth’s MF is neither a cause or the consequence of the climate change, but happen to be a passenger on the same train, so on occasions may be a good proxy.
The Earth’s dipole is the arithmetic sum of two poles intensity, currently both decay at similar rate, but the dipole changes are of no great consequence. For the MF-temps relationship the Antarctica hardly matters, but the Arctic’s pole (or to be more accurate the poles) location-time intensity distribution does.
For those inclined to a more speculative excursion into the subject, here I show some of my own personal findings. http://www.vukcevic.talktalk.net/NFC.htm http://www.vukcevic.talktalk.net/HmL.htm
Not everyone accepts Loehle or Ljungqvist temperature reconstructions as good, however there is an intriguing resemblance to the MF intensity sweep trough the Arctic Ocean. http://www.vukcevic.talktalk.net/LL1.htm
(delta t at 20, 30 or 40 years makes very little difference, see the inset)
[Response: How is this responsive? If the climate is not impacted by the dipole going almost to zero, it is isn’t responsive to tiny meanders of the North Pole. Or do you have some magical mechanism that only works for tiny changes but not large ones – climate homeopathy perhaps? – gavin]
63 Dan H. “If the Koch brothers knowingly distributed false information that resulted in harm to either people or the environment, then that is direct cause for legal action.”
Not only that, they and the rest of the fossil fuel industry spent $2 billion doing it. Documentation:
“Climate Cover-Up” by James Hoggan.
“Merchants of Doubt” by Oreskes and Conway
“Denying Science” by John Grant
And you can find a lot of damage reported in climateprogress. So why isn’t there a lawsuit already?
Oh, yes, they can argue that in this or that one case, it could be weather. Wasn’t a connection proven in 1 or 2 cases? But the fossil fuel industry could litigate for ever? But the publicity? Make it a law school project?
Would a small island nation that has been evacuated due to rising water have standing in some court? How about a country that has had a famine?
vukcevicsays
Gavin: climate homeopathy
Hank R: phrenology
Nothing as clever as the above. Higher order equations have more than solution, positive, negative, real or imaginary (i), all common in engineering, the imaginary solutions are bread and butter of the electrical and electronics world.
Since this happens to be the ‘RealClimate’, no imaginary parts in the above, just simply a cause with more than one consequence.
p.s.
had to google both expressions, the ‘climate homeopathy’ is the absolute classic, sorry Frank phrenology doesn’t ‘cut the mustard’.
The Laschamp and other ‘event’ signals are detectable but just blips in the sedimentary record, right?
Just looking at the bumps in the chart, there’s no way to say what should be read as a real distinct event — the variations are lost in the noise so far as analysis has gone, that I can see.
Just for example https://journals.uair.arizona.edu/index.php/radiocarbon/article/view/3834 (cited by many), which mentions “three intervals of highly increased (super 14) C concentrations coincident with low values of paleomagnetic field intensity, two of which are attributed to the geomagnetic Mono Lake and Laschamp excursions …. however, our Delta (super 14) C values seem to underestimate the atmospheric level, if compared to the (super 36) Cl flux measured in the GRIP ice core (Wagner et al. 2000) and other records. As this excursion coincides with a meltwater event in core PS2644, the underestimation is probably caused by an increased planktonic reservoir age. The same effect also occurs from 38.5 to 40 ka cal BP when the meltwater lid of Heinrich Event 4 affected the planktonic record.”
“… This requires careful assessment of the fundamental issues of magnitude and phasing of global ice volume fluctuations within marine isotope stage 3 (MIS 3), which to date remain enigmatic …”
You have to know there’s something under the bumps in the charts before declaring they represent something real.
It’s worth remembering just what was living on Earth and where at the particular times involved, and what traces we can find.
But I recall Gavin saying a few years back after a China meeting that most such work looks at its own core in detail but there needs to be a better worldwide collaboration to pull together more of a global picture from the relatively few scattered deep sediment/ice cores that have been drilled.
The paleo folks are making rapid progress — as are the folks working with live plankton.
Shotgun DNA PCR probes are turning up contemporary life forms we didn’t know existed because they wouldn’t grow in laboratories, all the time (that’s where you take a sample from an area, run it through a blender, then ‘probe’ with little segments of known DNA using the polymerase chain reaction (PCR). Whatever DNA in the mystery soup happens to correspond with the probe samples gets replicated (‘chain reaction’) approximately a zillion times, so there’s enough of it created to be actually identified. Piece _that_ information together and they can conclude from it that a particular kind of organism exists in the original site — then go look for the beastie knowing it has to be there somewhere.
Ron R.says
A bit of a lesson. Last month I mentioned that the Middle Miocene, with temperatures similar to that predicted for present day climate change, was a paradise for those animals evolved to it. That is undoubtedly true as evidenced by the Clarendonian Chronofauna.
What is a chronofauna?:
“Vertebrate paleontologists refer to persistent faunas of essentially uniform taxonomic composition and stable diversity as chronofaunas following Olsen (1952). In ecological terms, chronofaunas are thought to represent stable coadapted sets of species, and their detailed histories (under various perturbations) shed light on the theory of how communities or community complexes are structured (Olsen, 1983; Webb, 1987). – Effects of past global change on life http://tinyurl.com/7bove58
The Clarendonian Chronofauna ran somewhat parallel to others in the world ). “They are recorded from localities all over Eurasia, including the famous bone beds in Spain, France, Germany, and Italy, in Pikermi and Samos in Greece, in Maragheh in Iran, in the Siwalik Hills of northern Pakistan (fig. 6.26A}, in the Tunggur beds in Mongolia (fig. 6.26B), and in many deposits in China”. – After the dinosaurs: the age of mammals by Donald Prothero http://tinyurl.com/7cjd3yd
What created the Clarendonian Chronofauna?
“The most likely explanation for the observed species-rich browser palaeocommunities is an elevated level of primary productivity, relative to the present day, within (at least some) mid Miocene grassland habitats. Such an increase in productivity could possibly have been the result of higher-than-present levels of atmospheric carbon dioxide in the mid Miocene” – The species richness of Miocene browsers, and implications for habitat type and primary productivity in the North American grassland biome. http://tinyurl.com/74mhzze
“A moderate climate, sufficient precipitation, periodic deposits of volcanic ash, and the basaltic parent material combined to produce highly fertile soils, and from these soils arose lush, nutritious grasses and mixed hardwood forests, much like those found today in the eastern United States.” http://www.nature.nps.gov/geology/parks/joda/index.cfm
“Clarendonian Chronofauna: Grassland Savanna Land mammal diversity in North America reached its zenith during the Barstovian mammal age (Webb, 1989). Savage and Russell (1983) recognized 16 families with 60 genera and 141 nominal species of land mammals in the Barstovian. The next highest numbers occurred in the Clarendonian (the next mammal age), with 55 genera and 117 species. These mammal ages are thought to indicate a savanna optimum in North America, with a rich mosaic of trees, shrubs, and grasses supporting an extraordinary variety of large and small, grazing and browsing, ungulates. It is not uncommon during this savanna acme to collect in a single site 20 genera of ungulates of which half are Equidae (Webb, 1983a; Voorhies, 1990).” – Global Climatic Influence on Cenozoic Land Mammal Faunas
“Further major shifts are evident in the Middle Miocene, but in North America, these do not include significant numbers of immigrants. Instead, the acme of land mammal diversity, dominated by horses and other savanna herbivores, is attained in the Barstovian…. the land mammal faunas experienced high diversity and long stable community development (chronofaunal evolution). This lends credence to the view that the ecosystem was near capacity during the Barstovian acme and perhaps during other chronofaunal intervals.” – Effects of Past Global Change on Life
“The later Tertiary mammalian fauna of the World Continent was perhaps the richest that has ever existed on the face of the earth. It is as if mammalian life had been proliferating in ever increasing numbers, exploring every ecological nook and cranny that could be populated, testing how large or small you could get, how best to adorn yourself with tusks or horns, how to fly, swim, climb, run, dig, jump, hunt, eat, kill and defend yourself, better than ever before. All the manifestations have a single keyword:adaptation. Most of the evolutionary lines of the later Tertiary had a fairly long history behind them: they had got far enough to attain basic adaptation for a given way of life. What remained now was to perfect it. And so, in the late Tertiary, the mammals were increasing in efficiency, under the constant supervision of natural selection – a perfectionist potentate. And in general this would also involve an increase in beauty, in gracefulness, in elegance.” – The Age of Mammals, (chapter) The Miocene: Epoch of Revolutions by Björn Kurtén. Columbia University Press, 1971
“Looking back the Pliocene [or a timeframe within the Pliocene now called the Miocene] is something of a paradise lost, a climax of the Age of Mammals before the coming of the cold; a time when life was richer, more exuberant than ever before or after.” – The Age of Mammals, (chapter) The Pliocene: Epoch of Climax. Björn Kurtén
But then something changed. The climate, beginning around 14.5 ma. due to the opening of the Drake Passage, the creation of the Antarctic circumpolar current and the subsequent build up of the Antarctic ice sheet. It picked up speed at 13 ma. By the end of the Hemphillian around sixty two mammal genera had become extinct (corresponding to the Messinian Salinity Crisis around 6 Ma which created a drought-like condition worldwide ending in the Great Zanclean Flood).
“At the end of the Early Hemphillian (about 6.0 mya) North America experienced both an abrupt increase in aridity and a sharp increase in seasonal temperature extremes…. By then these events evidently triggered the most extensive land-mammal extinction episode in the entire Neogene record, eliminating most of the prominent elements of the Clarendonian Chronofauna…. The mass land mammal extinctions of the Mid-Hemphillian were even larger than the mass extinctions of the latest Pleistocene. The major differences are that during the Miocene mammals of all sizes were eliminated and that the hand of human hunting could not be blamed”. “The mid-Hemphillian mass extinction was the most severe in the record of North American land-mammal genera (Webb, 1984a). Most browsing taxa went extinct, presumably because climatic conditions became cooler and drier. The diversity of grazing and mixed feeding was also decimated”. – Paleoclimate and evolution, with emphasis on human origins
That tells us something about the sensitivity of animals to climate change. Long term they can adapt, but do we have that kind of time? Let’s not forget that we are all connected. What happens to them will impact us. I suspect that people can handle the temperature change itself (though all of the other attendant issues such as flooding, droughts etc. will be devastating) but will the majority of other species?
Make no mistake, their loss will be particularly impactful to us down the road.
—
Where do we stand in our efforts to achieve a sustainable world? Clearly, the past half century has been a traumatic one, as the collective impact of human numbers, affluence (consumption per individual) and our choices of technology continue to exploit rapidly an increasing proportion of the world’s resources at an unsustainable rate… during a remarkably short period of time, we have lost a quarter of the world’s topsoil and a fifth of its agricultural land, altered the composition of the atmosphere profoundly, and destroyed a major proportion of our forests and other natural habitats without replacing them. Worst of all, we have driven the rate of biological extinction, the permanent loss of species, up several hundred times beyond its historical levels, and are threatened with the loss of a majority of all species by the end of the 21st century.” – Peter Raven, then president of the American Association for the Advancement of Science in AAAS Atlas of Population & Environment
Posting links to papers on the intertubes is often meaningless, unless those papers have survived both peer review and better yet peer response.
Some guy wrote in a paper without having survived the aforementioned process is merely showing that you are willing to presenting unsubstantiated points as if they have substance, which has yet to be proven.
Does that make sense to you?
vukcevicsays
Addressed to # 47 John P. Reisman (OSS Foundation):
I wrote in my post:
“As far as I understand it, the Earth’s MF is neither a cause or the consequence of the climate change, but happen to be a passenger on the same train, so on occasions may be a good proxy.”
Perhaps the above escaped your attention in the haste to attribute or imply what is not stated in my post.
Ray Ladburysays
Vukcevic,
We understand the geomagnetic field–it is generated by convection of molten iron in the outer core and staibilized by the solid inner core, which acts as an inductor. It interacts with the heliomagnetic field, but those interactions are quite weak.
Thanks for the play-by-play, MARodger. But I re-read the whole thread from the start before reading your last post, and found out where my brain had picked up on the Dan H./co2science connection:
#45 Hank Roberts:
So it was a mistaken connection, and I was about to apologise… but now it looks like #97 Craig Nazor has caught Dan out. His true colours are shining through in that change.org thread. Thanks for that, Craig. Explains a lot.
For those who’ve paid the minimal AGU annual dues, the AGU member newspaper EOS has a couple of excellent articles on misconceptions and how to teach science by correcting them.
EOS, TRANSACTIONS, AMERICAN GEOPHYSICAL UNION
Improving Student Learning by Addressing Misconceptions
Volume 92 number 50. 13 December 2011 pages 465–476. Students—and often those who teach …
http://www.agu.org/journals/eo/v092/i050/…/2011EO500001_brr.pdf
What Do U.S. Students Know About Climate Change?
Dec 20, 2011 … significant misconceptions about the fundamental science behind it.
http://www.agu.org/journals/eo/v092/i051/…/2011EO510001_brr.pdf
These articles address basic misunderstandings, including denial PR — the same notions often rebunked here — as misconceptions, fundamentally wrong ideas about how the world works; teachers need to understand and address those directly.
AGU links, these are to abstracts everyone can look at:
Improving student learning by addressing misconceptions – AGU
http://www.agu.org/pubs/crossref/2011/2011EO500001.shtml
What do U.S. students know about climate change? – AGU
http://www.agu.org/pubs/crossref/2011/2011EO510001.shtml
(searching on the names reveals that a Pielke has already attacked the AGU’s position on teaching the science. I didn’t check to see which Pielke)
Further on misconceptions, the AGU piece reminded me I liked Michael Doliner’s post at https://www.realclimate.org/index.php/archives/2011/12/climate-cynicism-at-the-santa-fe-conference/comment-page-1/#comment-222494 where he writes about the steps toward understanding as a nonscientist. Worth another look, I suggest — each of the items he lists could have a stack of footnotes supporting/correcting/explaining it, but getting down to a simple set of steps toward understanding is a contribution.
@ Pete D #11 Thanks for the Hansen link – good stuff! Hansen said (http://www.columbia.edu/~jeh1/mailings/2011/20111110_NewClimateDice.pdf):
“The climate dice are now loaded to a degree that the perceptive person (old enough to remember the climate of 1951-1980) should be able to recognize the existence of climate change.”
I happen to have been thinking about the membership of that group of people for a while and it is smaller than we might at first think. A quick estimate goes like this:
Age group has to be 40+, since anyone under ten in the early 1980s won’t remember the old norms, and that rules out more than 50% of the world’s population and perhaps even more than 50% of the world’s voters.
But also, those people have to have been living in the same general area for 40+ years, or have returned to it after some time away, because no-one in California will say, “It wasn’t like this when I was a kid,” if they grew up in Normandy, Quebec or even Virginia. How many of us are that stable? 50%?
But also, the closer we live to nature, the more likely we are to notice its changes – but more and more of us are urbanised. How many of the 50% of 50% are therefore likely to qualify as “perceptive”? Less than 50% in the West, certainly; perhaps more than 50% in less urbanised countries.
That leaves less than 10% of the world’s population in a position to recognise, from personal observation, climate change. And (unfortunately for the debate) most of those 10% are the rural poor of developing nations, the most frequent victims of climate change not the opinion-makers of industrialised nations.
Canada after Kyoto
http://deepclimate.org/2012/01/06/canada-after-kyoto/
“Canada’s message: The world and its climate be damned”. That headline on Jeffrey Simpson’s scathing commentary on Canada’s pending formal withdrawal from the Kyoto Protocol said it all. …
But I want to turn today to an analysis of the Conservative government’s putative alternative to Kyoto, namely the 2009 Copenhagen agreement, as well as the GHG reduction plans put forth in 2008 by Canada and the province Alberta (home to the oil sands and Conservative Prime Minister Stephen Harper). That analysis confirms the contention of Jeffrey Simpson and others that the government of Canada is “mocking” the 2020 target agreed to only two years ago; the promised 17% reduction in annual GHG emissions (relative to 2005) is already out of reach. A big reason for this is an Alberta target (itself very unlikely to be met) that calls for a rise in GHG emissions until 2020. Not only that, but Alberta’s 2050 target, predicated on massive expansion of oil sands operations, is only 14% below 2005 levels, and sets Canada on a path that can not possibly be reconciled with the Harper government’s own stated long-term target, let alone any reasonable goal compatible with Canada’s responsibilities.
Einstein probably didn’t say that
Humanity’s epitaph:
1. Not Dead. Resting. (with apologies to Monty Python)
2. I told you we should have evolved faster.
3. We’ve all gone to Hell – it’s cooler there.
4. The meek inherited the Earth they deserved.
5. I hear Venus is pleasant at this time of year.
6. So long, and thanks for all the fossils.
7. So much plant food, so few plants …
8. Look on our works, Ye mighty, and despair.
@Hank Roberts#89
Thanks for the link to scholar.google.com. Not being a scientist, I have never stumbled on it before. Looks like a good way for an amateur to ‘get to the source’ and I will be glad to use it.
#106–Sadly, not a surprise. IMO, it’s been pretty clear for quite a while that the Harper government has a “good-faith” quotient on this issue that is indistinguishable from zero. They pay lip service to the importance of fighting climate change–‘lip service’ includes a few millions for arguably related measures–but play a role that is functionally highly obstructive. Just as sad, they are in this not that different from the preceding Liberal governments.
And this despite a public that regularly reports itself to be relatively convinced of the seriousness of the problem.
Ok, so just to ask the obvious question (someone has to): building on the FACE experiments and Hank’s comments about the fertilizer addition of nitrogen to the biosphere, if we were to, in a massive geoengineering experiment, artificially add N to the world’s forests (and possibly P & K), hopefully in an easy to breakdown, organic form, being careful to keep it away from waterways, might that allow those plant species within to increase their carbon intake and thus lower atmospheric CO2?
I really hesitate to mention something like this as there always seems to be serious and unacceptable side effects to our grandiose tinkering. Maybe it’s already been thought of and dismissed (like the ocean fertilization plan was) and I just missed the boat. Again.
Surely in urban areas trees are exposed to higher levels of atmospheric CO2, and to nitrogen, etc. from lawn fertilizers. Are urban trees significantly larger?
> if we were to, in a massive geoengineering experiment,
> artificially add N to the world’s forests (and possibly P & K)
We did that!
https://www.google.com/search?q=nitrogen+pollution+forest
http://scholar.google.com/scholar?q=nitrogen+pollution+forest+
As Eli pointed out recently, Su et al. suggest that our nitrogen oxide pollution has so far had the collateral benefit that “the oxidative capacity of the atmosphere has remained constant ….”
http://rabett.blogspot.com/2011/10/from-ground-up.html
” …. water aerosols where nitrogen dioxide has dissolved
H2O(aq) + 2 NO2(aq)= HNO3(aq) + HONO (g)
HONO is THE source of HO in the atmosphere ….”
…
“… and we know that agriculture is increasingly acidifying and fertilizing soils which is degrading water quality and increasing eutrophication. It may also have maintained the oxidative capacity of the atmosphere, leaving us lagomorphs with the choice of dirty air or dirty water ….”
——-
As you said, geoengineering. It’s the sort of thing only a sociopath would have funded, fifty years ago.
Oh, wait: http://mikethemadbiologist.com/2012/01/05/meet-the-new-boss-the-sociopath-as-banker/
AGU Membership: $20/year
http://www.agu.org/membership/
Well worth $20.
Membership is by calendar year.
This is the time to join, to get all the 2010 info.
That gets you abstracts and news (science journals cost more, but public libraries get them — if you know what to ask for. Basic membership info helps know what to ask).
http://www.swissre.com/rethinking/Shaping_the_global_climate_agenda.html
For Dan H.
Dr. Susan Prichard discusses the impact of bark beetles on western forests.
Also:
* Carbon Dioxide Enrichment Inhibits Nitrate Assimilation in Wheat and Arabidopsis. Bloom et al (2010).
* Sharply increased insect herbivory during the Paleocene–Eocene Thermal Maximum. (Currano 2007)
* Insects Will Feast, Plants Will Suffer: Ancient Leaves Show Affect Of Global Warming.
* Grassland Responses to Global Environmental Changes Suppressed by Elevated CO2. (Shaw 2007)
* Photosynthetic inhibition after long-term exposure to elevated levels of carbon dioxide. (DeLucia 1985)
* Insects Take A Bigger Bite Out Of Plants In A Higher Carbon Dioxide World.
* Crock of the Week – Don’t it make my Green World Brown
JCH @ 11:29 AM
Are urban trees significantly larger?
Interesting question. Problem is that urban areas tend to want to keep trees to and of a certain height. And nitrogen fertilizers are not evenly spread, just usually on grass and crops (though trees could probably pick some up in the water table).
Hmmm.
“There are also implications for global change models, which are beginning to include nitrogen availability as a factor affecting the response of plants to increasing atmospheric carbon dioxide concentrations,” said Turner. “Most models assume that higher nitrogen equals more plant growth, which would remove carbon from the atmosphere and offset future warming. However a challenge for the models is that there is no evidence that trees are growing faster in Panama, despite the long-term increases in nitrogen deposition and atmospheric carbon dioxide.”
http://www.sciencedaily.com/releases/2011/11/111103143243.htm
On the other hand
Houlton noted that nitrogen is becoming increasingly important in climate-change studies and researchers have begun to incorporate nitrogen in their climate-change models. Some models indicate that the nutrient could cause an additional increase in global temperatures of up to one degree Celsius (1.8 degrees Fahrenheit) by 2010, as it limits the amount of carbon dioxide that plants around the world can extract from the atmosphere. If more nitrogen is available than predicted from the traditional nitrogen-cycling pathways, as the UC Davis study suggests, it could lead to more carbon storage on land and less carbon remaining in the atmosphere.
http://www.sciencenewsline.com/nature/2011083122420020.html
Just out of curiosity, does anyone know the nitrogen content of volcanic rock?
> volcanic rock
Scholar finds many studies; here’s one review:
http://geology.geoscienceworld.org/content/27/6/567.abstract
Jumping back, I quoted from
Journal and Proceedings of the Royal Society of New South Wales, vol. 144, nos. 3&4, pp. 50-57.Page 4, ISSN 0035-9173/11/020050-8
Science advice and policy making
Robert M. May OM AC FRS FRSN
Lord May of Oxford
Zoology Department, Oxford University, Oxford OX1 3PS, UK
some of this bit:
“more than half of all the atoms of nitrogen and of
phosphorus in green plant material that grew
last year came from artificial fertilisers, rather
than the natural biogeochemical cycles”
The paper attributes that to
Conway, G.(1997) The Doubly Green Revolution;
Penguin Books, London, UK
*The original PDF seems unavailable; I read the Google cache, here:
from http://scholar.googleusercontent.com/scholar?q=cache:ej1lt2gNrB0J:scholar.google.com/+ISSN+0035-9173/11/020050-8&hl=en&as_sdt=0,5
I’m curious whether the “green plant material” is terrestrial or includes eutrophication; looking for more info on this rather astonishing number for nitrogen — though we’ve been making nitrogen fertilizer out of air for a long while; there’s no artificial source for phosphorous fertilizer, which is expected to be scarce rather soon.
Ron R. @many. You might want to read
Chmura et al. 2011. Forest responses to climate change in the northwestern United States: Ecophysiological foundations for adaptive management. Forest Ecology and Management 261:1121-1142. http://www.fs.fed.us/pnw/pubs/journals/pnw_2011chmura001.pdf
Conclusion of section on increased CO2:
Ron R.,
I am no scientist, but I have a bit of experience with horticulture, and here is my opinion concerning the FACE experiment.
It was an experiment done on ONE species of angiosperm tree – the American sweet gum, Liquidambar styraciflua. This tree is a primitive angiosperm. To think that ALL other species of trees will behave the same as this one, and then plan a fix for anthropogenic global climate change (AGCC) based on the reaction of one species of tree is not advisable, to say the least.
Also, as other posters have pointed out, CO2 levels are not the only limiting factor affecting plant growth. There are numerous experiments that show that, even if CO2 levels are high, plants cannot always take advantage of this because of limitations of water, nitrogen, and/or the availability of many trace elements. Nitrogen, in particular, is complicated when it comes to plants. Some species (with the aid of cyanobacteria) can essentially suck nitrogen out of the air. Most are not so lucky, and have to rely on all kinds of symbiotic relationships in the nitrogen cycle, which can be sensitive to all kinds of factors, including human tampering. AGCC could wreck havoc with any one of, or even all, of these plant needs. And different species out-competing each other for CO2 uptake and increased growth will drastically change whole ecosystems, with unknown consequences to carbon sequestration.
I would not rely on some kind of geo-engineering with the ability of a species of plant to sequester CO2 to save us from the worst effects of AGCC.
I would like to take this time to apologize to Hank for my statement about not linking to co2science. It appears that I did copy a link from co2science that was posted here last year (response #43).
https://www.realclimate.org/index.php/archives/2011/03/unforced-variations-mar-2011/
I was unaware that the link was to co2science as opening the link only reveals the letter, and does not lead on to the website. However, the evidence shows that I did post a link to co2science, so I will recant my statement. Sorry, Hank.
Question for Gavin: As it is January, will there be another “How are the models doing” post this year?
[Response: Yes. I’m waiting for some last minute updates (though the basic picture will not be different from last year, but I may have some new CMIP5 results to throw in the mix). – gavin]
Mr. Nazor @ 123
Summarized by Liebig’s Law of the Minimum
@Gavin
Cheers!
Craig,
The FACE experiments included aspens, birch, pine, poplars, and other hardwood trees also. The sweetgums were from the Oak Ridge tests (ORNL), which were the only species which showed a N-limitation.
Yes, CO2 is but one limiter of plant growth. In areas where species are water-limited, temperature-limited, N-limited (such as the sweetgums mentioned previously), or other nutrient-limited, increases in atmospheric CO2 will have minimal effects.
Dan H.
And of course we know climate change will also increase drought–implying by your own admission that atmospheric CO2 will have minimal fertilizing effects.
Dan H. misrepresents the paper _again_. They say they don’t know and suggest several possible explanations; Dan phrases his comment as though he knows the answer and it’s the one convenient for his talking point.
He’s using debate tactics to mislead, over and over.
“An unanswered question has been why the negative feedback through the N cycle developed in ORNL-FACE and not in other forested FACE experiments. There may be a fundamental difference in the biology of the various systems, such as a reliance on ectomycorrhizae as opposed to arbuscular mycorrhizae (Drake et al. 2011). Another possibility is that downregulation of forest growth response would have occurred across all experiments given enough time. Tissue turnover times are faster in the ORNL sweetgum stand than in the Duke-FACE pine stand, which may have accelerated the development of N limitation….”
Hank Roberts — 8 Jan 2012 @ 3:09 PM
Thanks for that Hank.
Craig Nazor — 9 Jan 2012 @ 3:45 AM
Also, as other posters have pointed out, CO2 levels are not the only limiting factor affecting plant growth. There are numerous experiments that show that, even if CO2 levels are high, plants cannot always take advantage of this because of limitations of water, nitrogen, and/or the availability of many trace elements. Nitrogen, in particular, is complicated when it comes to plants.
Hi Craig. Read my posts and you’ll find that I agree with you.
Somebody else take on chasing down stuff for a while, eh?
I’m just tired of it.
I want to learn about climate here from the scientists.
Checking every damn thing from consistently unreliable sources does lead to good information, but only on the parts of the science they misstate. That’s a poor sample of the breadth of the science I want to learn.
I’m increasingly fond of Deltoid’s approach to keeping conversations alive:
Jonas Thread : Deltoid
By popular request, here is the Jonas thread. All comments by Jonas and replies to his comments …
Tim Curtin thread : Deltoid
By request here is a new thread for folks to argue with Tim Curtin. Tim, this is the only thread you are allowed to post on….
scienceblogs.com/deltoid/2009/03/tim_curtin_thread.php
Hank,
I believe you just confirmed my statement that only the ORNL-FACE experiments showed N-limitations.
I continue to be most grateful to others who chase down bunk and debunk.
Belatedly, here’s one I recommend highly:
http://topologicoceans.wordpress.com/2011/09/16/co2-trouble/
“In this document, I have bundled, updated, and expanded my series of essays debunking the congressional testimony of Dr. John Everett regarding the environmental chemistry of carbon dioxide.
… A part of my John Everett series – read more: 0/I – II.0 – II.5 – II.75 – III.0 – III.3 – IV.0 – IV.4 – IV.8 – V – VII – VIII – Full Report
Dan, they tried to falsify a number of ideas. You point to one such result without context, and claim literal truth, making it sound like a generally applicable statement.
You’re debating. I’m not.
Read context, footnotes, citing papers.
Plonk.
Hank,
Who tried to falsify a number of ideas? Are you claiming entire FACE or just ORNL? Please elaborate, otherwise the remainder of your post is lost.
Dan, you know what a hypothesis is?
You know what a scientist does with a hypothesis?
You know where in the FACE paper you’ve been citing the authors list a number of hypotheses, and discuss each one, saying it was accepted, or rejected, or something more complex?
That.
For Dan.
http://undsci.berkeley.edu/teaching/misconceptions.php#b11
and
Doing Biology
http://www.mansfield.ohio-state.edu/~sabedon/biol1000.htm
(a) “In science seldom does a single test provide results that clearly support or falsify an hypothesis. In most cases the evidence serves to modify the hypothesis …
Good night.
Stirring the methane pot has gotten boring, how about something more intriguing – like the magnetosphere. David Suzuki’s Nature of Things had a program on the overdue flip that made passing reference to it’s possible influence on [or correlation with] climate, even had a cameo appearance by Svensmark. Has there been any work with the ACE data relating the earths magnetic field [moving/weakening] to climate?
[how the heck does CAPTCHA expect us to reproduce upside down words and arcane symbols??]
[Response: If the Earth’s magnetic field had a significant impact on climate (via any mechanism), you’d see something associated with the Laschamp event (40,000 years ago), or any of the magnetic reversal boundaries (e.g. the Brunes Matayama – 700,000 years ago). You don’t. – gavin]
[Response: If the Earth’s magnetic field had a significant impact on climate (via any mechanism), you’d see something associated with the Laschamp event (40,000 years ago), or any of the magnetic reversal boundaries (e.g. the Brunes Matayama – 700,000 years ago). You don’t. – gavin]
This also argues against cosmic ray intensity significantly affecting climate, doesn’t it, since cosmic rays intensity depends on the earth’s magnetic field. Maybe useful for an article if there is another denialist push of a “cosmic rays cause climate change” article.
[Response: This is already well known, see Wagner et al (2001) for instance. – gavin]
[Response: If the Earth’s magnetic field had a significant impact on climate (via any mechanism), you’d see something associated with the Laschamp event (40,000 years ago), or any of the magnetic reversal boundaries (e.g. the Brunes Matayama – 700,000 years ago). You don’t. – gavin]
There are number of misconceptions about possible Earth’s magnetic field – temperature relationship. As far as I understand it, the Earth’s MF is neither a cause or the consequence of the climate change, but happen to be a passenger on the same train, so on occasions may be a good proxy.
The Earth’s dipole is the arithmetic sum of two poles intensity, currently both decay at similar rate, but the dipole changes are of no great consequence. For the MF-temps relationship the Antarctica hardly matters, but the Arctic’s pole (or to be more accurate the poles) location-time intensity distribution does.
For those inclined to a more speculative excursion into the subject, here I show some of my own personal findings.
http://www.vukcevic.talktalk.net/NFC.htm
http://www.vukcevic.talktalk.net/HmL.htm
Not everyone accepts Loehle or Ljungqvist temperature reconstructions as good, however there is an intriguing resemblance to the MF intensity sweep trough the Arctic Ocean.
http://www.vukcevic.talktalk.net/LL1.htm
(delta t at 20, 30 or 40 years makes very little difference, see the inset)
[Response: How is this responsive? If the climate is not impacted by the dipole going almost to zero, it is isn’t responsive to tiny meanders of the North Pole. Or do you have some magical mechanism that only works for tiny changes but not large ones – climate homeopathy perhaps? – gavin]
> intriguing resemblance
phrenology, seems like
63 Dan H. “If the Koch brothers knowingly distributed false information that resulted in harm to either people or the environment, then that is direct cause for legal action.”
Not only that, they and the rest of the fossil fuel industry spent $2 billion doing it. Documentation:
“Climate Cover-Up” by James Hoggan.
“Merchants of Doubt” by Oreskes and Conway
“Denying Science” by John Grant
And you can find a lot of damage reported in climateprogress. So why isn’t there a lawsuit already?
Oh, yes, they can argue that in this or that one case, it could be weather. Wasn’t a connection proven in 1 or 2 cases? But the fossil fuel industry could litigate for ever? But the publicity? Make it a law school project?
Would a small island nation that has been evacuated due to rising water have standing in some court? How about a country that has had a famine?
Gavin: climate homeopathy
Hank R: phrenology
Nothing as clever as the above. Higher order equations have more than solution, positive, negative, real or imaginary (i), all common in engineering, the imaginary solutions are bread and butter of the electrical and electronics world.
Since this happens to be the ‘RealClimate’, no imaginary parts in the above, just simply a cause with more than one consequence.
p.s.
had to google both expressions, the ‘climate homeopathy’ is the absolute classic, sorry Frank phrenology doesn’t ‘cut the mustard’.
The Laschamp and other ‘event’ signals are detectable but just blips in the sedimentary record, right?
Just looking at the bumps in the chart, there’s no way to say what should be read as a real distinct event — the variations are lost in the noise so far as analysis has gone, that I can see.
Just for example https://journals.uair.arizona.edu/index.php/radiocarbon/article/view/3834 (cited by many), which mentions “three intervals of highly increased (super 14) C concentrations coincident with low values of paleomagnetic field intensity, two of which are attributed to the geomagnetic Mono Lake and Laschamp excursions …. however, our Delta (super 14) C values seem to underestimate the atmospheric level, if compared to the (super 36) Cl flux measured in the GRIP ice core (Wagner et al. 2000) and other records. As this excursion coincides with a meltwater event in core PS2644, the underestimation is probably caused by an increased planktonic reservoir age. The same effect also occurs from 38.5 to 40 ka cal BP when the meltwater lid of Heinrich Event 4 affected the planktonic record.”
Or this http://www.agu.org/pubs/crossref/2008/2007RG000226.shtml review as of 2008, which says
“… This requires careful assessment of the fundamental issues of magnitude and phasing of global ice volume fluctuations within marine isotope stage 3 (MIS 3), which to date remain enigmatic …”
You have to know there’s something under the bumps in the charts before declaring they represent something real.
It’s worth remembering just what was living on Earth and where at the particular times involved, and what traces we can find.
But I recall Gavin saying a few years back after a China meeting that most such work looks at its own core in detail but there needs to be a better worldwide collaboration to pull together more of a global picture from the relatively few scattered deep sediment/ice cores that have been drilled.
The paleo folks are making rapid progress — as are the folks working with live plankton.
Shotgun DNA PCR probes are turning up contemporary life forms we didn’t know existed because they wouldn’t grow in laboratories, all the time (that’s where you take a sample from an area, run it through a blender, then ‘probe’ with little segments of known DNA using the polymerase chain reaction (PCR). Whatever DNA in the mystery soup happens to correspond with the probe samples gets replicated (‘chain reaction’) approximately a zillion times, so there’s enough of it created to be actually identified. Piece _that_ information together and they can conclude from it that a particular kind of organism exists in the original site — then go look for the beastie knowing it has to be there somewhere.
A bit of a lesson. Last month I mentioned that the Middle Miocene, with temperatures similar to that predicted for present day climate change, was a paradise for those animals evolved to it. That is undoubtedly true as evidenced by the Clarendonian Chronofauna.
What is a chronofauna?:
“Vertebrate paleontologists refer to persistent faunas of essentially uniform taxonomic composition and stable diversity as chronofaunas following Olsen (1952). In ecological terms, chronofaunas are thought to represent stable coadapted sets of species, and their detailed histories (under various perturbations) shed light on the theory of how communities or community complexes are structured (Olsen, 1983; Webb, 1987). – Effects of past global change on life
http://tinyurl.com/7bove58
The Clarendonian Chronofauna ran somewhat parallel to others in the world ). “They are recorded from localities all over Eurasia, including the famous bone beds in Spain, France, Germany, and Italy, in Pikermi and Samos in Greece, in Maragheh in Iran, in the Siwalik Hills of northern Pakistan (fig. 6.26A}, in the Tunggur beds in Mongolia (fig. 6.26B), and in many deposits in China”. – After the dinosaurs: the age of mammals by Donald Prothero
http://tinyurl.com/7cjd3yd
What created the Clarendonian Chronofauna?
“The most likely explanation for the observed species-rich browser palaeocommunities is an elevated level of primary productivity, relative to the present day, within (at least some) mid Miocene grassland habitats. Such an increase in productivity could possibly have been the result of higher-than-present levels of atmospheric carbon dioxide in the mid Miocene” – The species richness of Miocene browsers, and implications for habitat type and primary productivity in the North American grassland biome.
http://tinyurl.com/74mhzze
“A moderate climate, sufficient precipitation, periodic deposits of volcanic ash, and the basaltic parent material combined to produce highly fertile soils, and from these soils arose lush, nutritious grasses and mixed hardwood forests, much like those found today in the eastern United States.”
http://www.nature.nps.gov/geology/parks/joda/index.cfm
“Clarendonian Chronofauna: Grassland Savanna Land mammal diversity in North America reached its zenith during the Barstovian mammal age (Webb, 1989). Savage and Russell (1983) recognized 16 families with 60 genera and 141 nominal species of land mammals in the Barstovian. The next highest numbers occurred in the Clarendonian (the next mammal age), with 55 genera and 117 species. These mammal ages are thought to indicate a savanna optimum in North America, with a rich mosaic of trees, shrubs, and grasses supporting an extraordinary variety of large and small, grazing and browsing, ungulates. It is not uncommon during this savanna acme to collect in a single site 20 genera of ungulates of which half are Equidae (Webb, 1983a; Voorhies, 1990).” – Global Climatic Influence on Cenozoic Land Mammal Faunas
http://www.nap.edu/books/0309051274/html/184.html
“Further major shifts are evident in the Middle Miocene, but in North America, these do not include significant numbers of immigrants. Instead, the acme of land mammal diversity, dominated by horses and other savanna herbivores, is attained in the Barstovian…. the land mammal faunas experienced high diversity and long stable community development (chronofaunal evolution). This lends credence to the view that the ecosystem was near capacity during the Barstovian acme and perhaps during other chronofaunal intervals.” – Effects of Past Global Change on Life
http://www.nap.edu/openbook.php?record_id=4762&page=203
“The later Tertiary mammalian fauna of the World Continent was perhaps the richest that has ever existed on the face of the earth. It is as if mammalian life had been proliferating in ever increasing numbers, exploring every ecological nook and cranny that could be populated, testing how large or small you could get, how best to adorn yourself with tusks or horns, how to fly, swim, climb, run, dig, jump, hunt, eat, kill and defend yourself, better than ever before. All the manifestations have a single keyword:adaptation. Most of the evolutionary lines of the later Tertiary had a fairly long history behind them: they had got far enough to attain basic adaptation for a given way of life. What remained now was to perfect it. And so, in the late Tertiary, the mammals were increasing in efficiency, under the constant supervision of natural selection – a perfectionist potentate. And in general this would also involve an increase in beauty, in gracefulness, in elegance.” – The Age of Mammals, (chapter) The Miocene: Epoch of Revolutions by Björn Kurtén. Columbia University Press, 1971
“Looking back the Pliocene [or a timeframe within the Pliocene now called the Miocene] is something of a paradise lost, a climax of the Age of Mammals before the coming of the cold; a time when life was richer, more exuberant than ever before or after.” – The Age of Mammals, (chapter) The Pliocene: Epoch of Climax. Björn Kurtén
http://books.google.com/books/about/The_age_of_mammals.html?id=ksZLAQAAIAAJ
But then something changed. The climate, beginning around 14.5 ma. due to the opening of the Drake Passage, the creation of the Antarctic circumpolar current and the subsequent build up of the Antarctic ice sheet. It picked up speed at 13 ma. By the end of the Hemphillian around sixty two mammal genera had become extinct (corresponding to the Messinian Salinity Crisis around 6 Ma which created a drought-like condition worldwide ending in the Great Zanclean Flood).
“At the end of the Early Hemphillian (about 6.0 mya) North America experienced both an abrupt increase in aridity and a sharp increase in seasonal temperature extremes…. By then these events evidently triggered the most extensive land-mammal extinction episode in the entire Neogene record, eliminating most of the prominent elements of the Clarendonian Chronofauna…. The mass land mammal extinctions of the Mid-Hemphillian were even larger than the mass extinctions of the latest Pleistocene. The major differences are that during the Miocene mammals of all sizes were eliminated and that the hand of human hunting could not be blamed”. “The mid-Hemphillian mass extinction was the most severe in the record of North American land-mammal genera (Webb, 1984a). Most browsing taxa went extinct, presumably because climatic conditions became cooler and drier. The diversity of grazing and mixed feeding was also decimated”. – Paleoclimate and evolution, with emphasis on human origins
http://tinyurl.com/6vkmclk
You can see a supporting graph here (Fig. 11.4): http://www.nap.edu/openbook.php?record_id=4762&page=203
That tells us something about the sensitivity of animals to climate change. Long term they can adapt, but do we have that kind of time? Let’s not forget that we are all connected. What happens to them will impact us. I suspect that people can handle the temperature change itself (though all of the other attendant issues such as flooding, droughts etc. will be devastating) but will the majority of other species?
Climate change models flawed, extinction rate likely higher than predicted http://tinyurl.com/6w5wog5
Make no mistake, their loss will be particularly impactful to us down the road.
—
Where do we stand in our efforts to achieve a sustainable world? Clearly, the past half century has been a traumatic one, as the collective impact of human numbers, affluence (consumption per individual) and our choices of technology continue to exploit rapidly an increasing proportion of the world’s resources at an unsustainable rate… during a remarkably short period of time, we have lost a quarter of the world’s topsoil and a fifth of its agricultural land, altered the composition of the atmosphere profoundly, and destroyed a major proportion of our forests and other natural habitats without replacing them. Worst of all, we have driven the rate of biological extinction, the permanent loss of species, up several hundred times beyond its historical levels, and are threatened with the loss of a majority of all species by the end of the 21st century.” – Peter Raven, then president of the American Association for the Advancement of Science in AAAS Atlas of Population & Environment
http://atlas.aaas.org/index.php?sub=foreword
#139 flxible
# 141 vukcevic
Interesting possible new line of silliness on the magnetic flip.
Hint number one for me of relatively high levels of silliness is anything that has Svensmark in it. Yes, I am prejudiced by his past work.
http://ossfoundation.us/projects/environment/global-warming/galactic-cosmic-rays
http://ossfoundation.us/projects/environment/global-warming/myths/henrik-svensmark
Dan H.
Posting links to papers on the intertubes is often meaningless, unless those papers have survived both peer review and better yet peer response.
Some guy wrote in a paper without having survived the aforementioned process is merely showing that you are willing to presenting unsubstantiated points as if they have substance, which has yet to be proven.
Does that make sense to you?
Addressed to # 47 John P. Reisman (OSS Foundation):
I wrote in my post:
“As far as I understand it, the Earth’s MF is neither a cause or the consequence of the climate change, but happen to be a passenger on the same train, so on occasions may be a good proxy.”
Perhaps the above escaped your attention in the haste to attribute or imply what is not stated in my post.
Vukcevic,
We understand the geomagnetic field–it is generated by convection of molten iron in the outer core and staibilized by the solid inner core, which acts as an inductor. It interacts with the heliomagnetic field, but those interactions are quite weak.