Well, someone finds a well proven 2000 year cooling trend with MWP and RWP

http://www.sciencedaily.com/releases/2012/07/120709092606.htm

Climate in northern Europe reconstructed for the past 2,000 years: Cooling trend calculated precisely for the first time
Date: July 9, 2012

Source:
Universität Mainz

Summary:

Scientists have published a reconstruction of the climate in northern Europe over the last 2,000 years based on the information provided by tree-rings. Researchers used tree-ring density measurements from sub-fossil pine trees originating from Finnish Lapland to produce a reconstruction reaching back to 138 BC. In so doing, the researchers have been able for the first time to precisely demonstrate that the long-term trend over the past two millennia has been towards climatic cooling.

Yes, from 2012, so a couple of years back. But somehow I’d missed it. Uses tree rings, but does it in a smart way with well preserved trees from under sediments / fossils.

What did they find?

A long term down trend. Fairly warm MWP and Roman WP, with cold half cycles following each. Present warming not at all unusual.

An international team that includes scientists from Johannes Gutenberg University Mainz (JGU) has published a reconstruction of the climate in northern Europe over the last 2,000 years based on the information provided by tree-rings. Professor Dr. Jan Esper’s group at the Institute of Geography at JGU used tree-ring density measurements from sub-fossil pine trees originating from Finnish Lapland to produce a reconstruction reaching back to 138 BC. In so doing, the researchers have been able for the first time to precisely demonstrate that the long-term trend over the past two millennia has been towards climatic cooling.

“We found that previous estimates of historical temperatures during the Roman era and the Middle Ages were too low,” says Esper. “Such findings are also significant with regard to climate policy, as they will influence the way today’s climate changes are seen in context of historical warm periods.” The new study has been published in the journal Nature Climate Change.

Well Golly! It actually got published, and without a hokey hockey stick…

Then they actually give a (polite) small slap to the IPCC:

In addition to the cold and warm phases, the new climate curve also exhibits a phenomenon that was not expected in this form. For the first time, researchers have now been able to use the data derived from tree-rings to precisely calculate a much longer-term cooling trend that has been playing out over the past 2,000 years. Their findings demonstrate that this trend involves a cooling of -0.3°C per millennium due to gradual changes to the position of the sun and an increase in the distance between the Earth and the sun.

“This figure we calculated may not seem particularly significant,” says Esper, “however, it is also not negligible when compared to global warming, which up to now has been less than 1°C. Our results suggest that the large-scale climate reconstruction shown by the Intergovernmental Panel on Climate Change (IPCC) likely underestimate this long-term cooling trend over the past few millennia.”

Looks to me like some small snippets of truth are finally being published, now that the attempted influence of editors has been exposed via the ClimateGate emails.

So the “net net” of it all is that we are continuing the very long slow slide into the next glacial (that takes a while to get rolling); and we have a roughly 1000 year ‘peak to peak’ warm excursion with peaks at about 0 A.D., about 1000 A.D. and about now. Guess what comes next…

Our present ‘warming’ on that graph is absolutely normal, and the next down turn will be to a lower low than the Little Ice Age. Though even the ‘fast onset’ wiggles like the one near 400 A.D. take a couple of hundred years to get from top to bottom, so “we” are unlikely to see the full drop in any one lifetime, and what things are like in 2400 A.D. will likely be a lot colder, but in a world far different from this one anyway. (Do you really think that 400 more years of Islamic Militancy, Nuclear Proliferation, and technological change will leave the world recognizable as being ‘just like now’? Think what the world of 1600 A.D. was like, and we are changing faster now, than then.)

We’ve also got a good 1/2 C of upside to maybe even 1.5 C of upside range (the Holocene Optimum was even warmer and is not on this graph) from present temperatures before we are ‘warmer than in the past’, and the past was pretty good, so in my book that means “No Worries”.

Overall, this trend says to me that IF we are very very lucky, burning all the carbon based fossil fuels we can might just slow our decent into the next Ice Age Glacial. Maybe. For a little while. If not, we get frozen, but that’s going to happen in any case, just a question of when. In no case can we keep making things warmer at a rate sufficient to permanently overcome the long term down trend AND the next cyclical dip of a couple of degrees C, and stay “like things are now”. At best, we drop to about -1.5 C instead of the deeper dip to -1.8 C otherwise expected compared to the Little Ice Age (i.e. to ‘about the same’ instead of ‘deeper due to downtrend’). But that would at least be not yet into the glacial. One hopes.

Then again, I’m pretty sure that CO2 does nothing in the troposphere and is a trivial addition to the radiative loss from the stratosphere, with water being by far dominant, so it’s most likely we just keep on ‘wobbling downward’ on that long term slope until we hit a water / ice knee and the Arctic stays frozen one summer. After that comes the much more rapid plunge into the Glacial. Hopefully not for another couple of hundred years. Maybe…

Subscribe to feed

About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in AGW Science and Background and tagged , , . Bookmark the permalink.

14 Responses to Well, someone finds a well proven 2000 year cooling trend with MWP and RWP

  1. p.g.sharrow says:

    Only need another hundred years or so and we will be able to bring comets into orbit around the earth, they will sublimate and add to the Earth’s atmosphere. A change of a couple hundred feet in density altitude should add enough insulation, (real greenhouse effect) to add to the surface warmth.
    My son thinks I should spend more effort on the experiment. :-) pg

  2. Petrossa says:

    Whilst i do believe the overall conclusion the only thing bothering me using tree rings… for obvious reasons, Mann has so thoroughly discredited this proxy method it rankles a bit to see it being used to prove the opposite.

  3. Slywolfe says:

    Published in 2012, so M.Mann was probably aware of this paper and has had nothing to say about it? Or does he just not keep up with developments in his specialty?

  4. Svend Ferdinandsen says:

    To believe tree rings i still need a proof that show how they can tell of temperature and not precipitation and all other influences. They could have used other methods than size, f. inst. isotopes. Does anyone knows?

  5. omanuel says:

    Thanks for information I overlooked too.

    Gradual cooling over 2,000 years is much longer than seventy years (70 yrs) of common misunderstanding of the source of energy in, and physical structure of, neutron-rich cores of

    1. Heavy atoms like Uranium,
    2. Gaseous planets like Jupiter,
    3. Ordinary stars like the Sun,
    4. Galaxies like the Milky Way.

    https://dl.dropboxusercontent.com/u/10640850/Solar_Energy_For_Review.pdf

    If the 1945 decision to Unite Nations to achieve “UN’s Agenda 21:”

    http://habitat.igc.org/agenda21/index.htm

    also explains worldwide collusion to obscure the force of creation with a:

    1. Standard Nuclear Model
    2. Standard Climate Model
    3. Standard Solar Model &
    4. Big Bang Cosmology . . .

    If so, world leaders may be tempted to take drastic action, like a “false flag” nuclear war, to stay in power.

    America is lost if we accept as true the post-1945 “science” designed to destroy faith in a “Higher Power.”

  6. Svend Ferdinandsen says:

    Seems they have used density of the rings. I still dont trust the findings.

  7. Pingback: Paper Shows Todays Climate Par For Course Hockey Stick Absent | Power To The People

  8. Ian W says:

    I can’t say that I trust treemometers either. However, it may also be unsafe to trust the idea that temperatures will only drop in the same pattern as they have been. Chaotic systems do not necessarily repeat the same pattern and a change to a new attractor can be quite rapid if the system gets close to it while in the wrong state. The frozen Mammoths that have been found for example were still chewing fresh vegetation and had chewed vegetation in their stomachs – they were not hungrily roaming a frozen tundra and dying of starvation. There have been cases of finding blooming flowers buried under layers of ice. This seems to show that cold can come very rapidly.

  9. E.M.Smith says:

    @Svend:

    Tree rings respond to all growing condition inputs. Temperature, sun, cold, water, even fertilizer (a bear and his favorite tree ;-)

    However, with enough samples ( i.e. a lot of wood from below sediments) you can eliminate the idiosyncratic things (like one tree being shaded or another having a ‘pet bear’…) and get the broad effects. Yes, it is important to look for broad environmental changes (like water levels) so that you know the residual is largely temperature. In this case, the are assuring it is wood from places that are consistently wet ( under water in sediments – wood is preserved when wet, so the wood existing at all says it didn’t dry out there…) and that tends to come with consistent general fertilizer levels ( i.e. the same environment of living and dying things).

    So while your skepticism is well justified, it’s a heck of a lot better job than was done by Mr. Mann and his too few trees with too many idiosyncrasies and too few controls on environment change.

    Also note that nearer the Arctic Circle, tree growth is much more temperature sensitive (even have a ‘limit of trees’ when too cold, so simply finding historical tree lines tells temps – like the ancient tree bits found above the Arctic Circle today tell us that the Holocene Optimum was significantly warmer than now – since no trees can grow there at all now.) This means that the temperature effects dominate the ‘other effects’ on growth in that type of forest (very cold wet lands).

    @Petrossa:

    Yes; but it would be really fun to watch the Warmistas trying to discredit tree rings as thermometers ;-) This goes “toe to toe” with M. Mann and forces folks to look at just HOW the two series were done, which has the better samples and methods, and does much to make the Hockey Stick a provable farce.

  10. E.M.Smith says:

    @Ian W:

    I have my own ‘pet theory’ on the mammoth and similar. A slush wall being thrown, tsunami like, over the pole from an impact event into the glacial shield. The ‘layers’ where those animals are found are all ‘jumbled’, with the look of things being mixed and shaken. Now a large rock fall into the Canadian Glacier would cause an explosive melt / hole in the ice (but not a crater in the rock). At some distance from that event, the pressure waves in the ice would turn into a slush wall pushed along by air blast. Nothing like being suddenly encased in a few million tons of slush ice to rapidly cool you and mess up the grazing…

    I’ve done enough canning to know that to stop decay rapidly (after a ‘blanch’ for example) takes a plunge into ice water. No amount of air cooling will stop enzyme activity fast enough, especially inside of a few hundred pounds of meat instead of one little fruit…

    Though your major point remains:

    Even if the “punctuated equilibrium” impact argument can set the mammoths aside, the fact is that the temperature proxy series show repeated rapid events, not related to impacts. The Bond Event cycle, for example. Every 1500 years, on average, a sudden swing. While, IMHO, that is lunar / tidal caused; the fact is we don’t know. It’s an “attractor” of some kind, but in this case a quasi-periodic one. And that indicates that a non-periodic one can also cause the same thing.

    (It is quasi-periodic in that the average is 1470 years, but there are divergences to each side, with a decent argument for a 1200 / 1800 year pair that only averages to 1470 with the difference being that one lunar ‘cycle’ can be ‘short one’ or ‘long one’ depending on just how all the other orbital forces line up… so the ‘cycle’ can be attracted one way or the other a chunk…)

    Some things happen catastrophically fast and are likely, but not guaranteed, to be event driven by external things like impacts.

    Some things are periodic, and clearly traced to orbital mechanics. They tend to be slower and more sine wave in shape.

    Some things are quasi-periodic and seem to have more variable (sometimes rapid) onset, but sometimes with a semi-sine wave underlayment.

    Now mix, stir, and set in motion. Yeah, you could have something fast happen all by itself as oceans, moon and sun, planets, ice and albedo and who knows what all else fight over who wins the attraction contest…

    Then toss in a periodic / resonant meteor storm and impacts just for spice…

    https://chiefio.wordpress.com/2011/11/03/lunar-resonance-and-taurid-storms/

  11. Svend Ferdinandsen says:

    @E.M. Smidth
    Thanks for the response, and they could have a point. I would just like some references to papers that prove that you can extract temperature (how to do it) and not all the other parameters.
    I think McIntyre has some investigation on his agenda, and i look forward to that.

  12. Ian W says:

    Do a validation.
    Run a set of treemometers from say 1800 through to 10 years ago using the methodology that is claimed to work. The treemometers should have no decline to hide. They should all show the same variations as the local thermometer observations. If the validation works then great if it doesn’t there are a lot of papers that will need to be withdrawn.

  13. Svend Ferdinandsen says:

    A crucial point is how they converted density to temperature. Normally a sort of calibration versus known temperature is done, but that leaves a lot of questions open.

  14. Jason Calley says:

    “2400 A.D. will likely be a lot colder, but in a world far different from this one anyway. (Do you really think that 400 more years of Islamic Militancy, Nuclear Proliferation, and technological change will leave the world recognizable as being ‘just like now’?”

    I am reminded of a Sufi story… A wise man once learned the language of ants. Talking with an ant one day, he asked, “Do ants believe that God is like a Great Ant?” The ant replied, “Oh, no! God is not like an ant at all! We have only one stinger, but God has TWO!”

    Well, the world of 2400 A.D. will obviously be VERY different from today. Our digital watches will have much stronger wristbands, and the hubcaps on the automobiles will be MUCH larger!

    :)

Comments are closed.