Guest post by J Storrs Hall
There are several ways to predict what the temperature trends of the next century will be like. The standard method of prediction in science is to create a theory which embodies a model, test the model experimentally, and then run it into the future for the prediction. There is another way, however, which is simpler in some ways although more complex in others. That’s simply to remember what’s happened before, and assume it will happen again.
Here’s a record of what’s happened before, which most WUWT readers will be familiar with. It’s the GISP2 Greenland ice core record, shown for the Holocene:
I have shamelessly spliced on the instrumental record in red (by setting the temps in 1850 equal); it is the HadSST record.
When I first started looking at GISP2 it seemed to me that there were several places in the record that looked very much like the sharp spike in temperature we’re experiencing now. The obvious thing thing to do seems to be to overlay them for an easy comparison:
Here I’ve plotted the 400 years following each minimum in the record that leads to a sustained sharp rise. There were 10 of them; the first five are plotted in cyan and the more recent 5 in blue. You can see that in the latter part of the Holocene the traces settle down from the wilder swings of the earlier period. Even so, every curve, even the early ones, seems to have an inflection — at least a change in slope — somewhere between 200 and 250 years after the minimum.
The hatched black line is the average of the 5 recent (blue) spikes. The red dots are the uptick at the end of GISP2 and HadSST, spliced at 1850. Note that ALL the minima dates are from GISP2.
Prediction of the 21st century is left to the reader as an exercise.
Read ’em and weep.
Theo: “Looking at past graphs for patterns that resemble existing patterns is harmless enough and might give people some good ideas. However, it is not different in principle from reading chicken bones.”
There are cycles. There are previous interglacials. Ignoring them because someone else has a wacked out CO2 theory — when CO2 has always followed warming — is kind of silly.
Comparing sun cycles from the past to sun cycles in the present is more than “reading chicken bones”. Sure, its nice to have an elegant theory and big pocketful of grant money, or even NASA behind you … but it doesn’t make you any good at predicting the suns next move.
Stephen Pruett says:
July 1, 2011 at 6:56 pm
Look up Kepler’s Three Laws. They are all over the internet, and that is for a reason. Kepler was the first to use hypotheses to explain a phenomena, the orbits of the planets as observed from Earth, and to predict some very interesting observable facts from those hypotheses. Galileo took Kepler’s work and explicated scientific method for anyone who has an open mind. Newton created the math that enabled rigorous formulation of Kepler’s hypotheses. Kepler’s Laws are derivable from Newton’s Theory of Gravitation. If you ride a roller coaster today, no matter how wild, you are riding a machine designed from Kepler’s Laws.
The system of epicycles that came from Ptolemy (100 AD) and was preserved by Copernicus is something like a computer model; however, planetary orbits are not circles and they are not circles upon circles. Kepler had the synthetic genius to create new hypotheses that organized the data in a new way, that explained the phenomena, and that enabled prediction of the phenomena. Galileo drove people mad by using a telescope to show that Kepler’s Three Laws were correct. For that he was placed under house arrest without medical attention for the remainder of his life. He wrote a new book and smuggled it out to a Protestant country.
AGW is based on a misapplication of the scientific method. By counting all the times AGW can be shown to be right, this is taken as proof that it is right. This is not the scientific method. It is propaganda, it is marketing, is is politics, it is cultism, it is religion, but it is not science. Otherwise, the fact that a stopped clock is right 700+ times a year would be evidence that a stopped clock keep perfect time, while the fact that a working clock is rarely if every right is proof that working clocks do not keep time.
NikFromNYC: Actually, I don’t really care much about what the warmists think. I’m just trying to figure out what *I* think about what’s likely in the next century. I was a bit surprised to see all the spikes peaking at roughly the same timeframe, even though their heights varied by a factor of six.
BTW, “skepticalscience” is so obviously political that it’s not worth the time it takes to read it.
Think of it this way: suppose you were forced to wager you house on what the temp would be in 2050. Who would you read, what calcs would you do? I frankly don’t know of any model I’d trust the output of better than simple comparison with the record. Of course, splicing the instrumental record is totally cheesy and I wouldn’t trust it for good relative temp values — but the key parameter in this set of traces turns out — surprisingly — not to be temps at all, but times. So we can be more confident than if we were judging something by the height of the dotted line. That said, this remains no more than a back-of-the-envelope ansatz. But one it might be worth following up.
John A says:
July 1, 2011 at 4:01 pm
Am I the only one hoping for more global warming?
and several here reveal he is not. But there is a catch: actual warming causes the Environazis to ponder drastic action which gravely endangers us all.
They do not care that more people die of winter chill than summer heat. They have never noticed at what temperatures grass grows best.
And anyhow, many of them are perfectly willing to kill anything else alive as long as they damage people.
Bruce says:
July 1, 2011 at 8:13 pm
“There are cycles. There are previous interglacials. Ignoring them because someone else has a wacked out CO2 theory — when CO2 has always followed warming — is kind of silly.”
I did not say that you should ignore them. They can be used in many ways. However, looking at graphs of older times and recognizing that they resemble graphs of present times is only a beginning. You may choose to take that beginning and create some science upon it. But scientific hypotheses are far more sophisticated than that. Take Kepler’s First Law as an example. It states that all planetary orbits are ellipses that have the sun at one of the foci. It organizes the data. All observations of planetary orbits from Earth should confirm that the planet in question is travelling in an ellipse with the sun at one foci. How can you get something like that from the fact that there were patterns in previous inter-glacials? Ancient astronomers knew of many patterns in the movements of planets, but they could explain diddly and predict diddly.
John Q. Galt says:
July 1, 2011 at 5:57 pm
Nightly lows in upstate New York are getting ridiculous. I had to close the windows last night as it was absolutely frigid.
Summer hasn’t started in Vancouver. Rainy and cold with a couple of nice days thrown in along the way. Still lots of snow on the local mountains. The calendar says July but outside it is more like April.
kadaka (KD Knoebel) says:
July 1, 2011 at 7:05 pm
From Mike on July 1, 2011 at 5:24 pm:
“Follow the science. Hint: science is done by scientists not blogggers.”
kadaka, thank you for emphasizing this point. Science is the critical enterprise par excellence. Some scientists are fortunate enough to create hypotheses that organize the data in new ways, that explain the data, and that enable prediction of future data. All scientists then criticize the proposed hypothesis, including the scientist who proposed it. That is the way science advances. Any person who is adverse to criticism of what he proposes is not a scientist.
Bruce says:
July 1, 2011 at 8:13 pm
Theo: …………….
There are cycles. There are previous interglacials. Ignoring them because someone else has a wacked out CO2 theory — when CO2 has always followed warming — is kind of silly.
====================================================================
Bruce, I’m not Theo, and I can’t speak for him, but I don’t believe that’s what he was stating.
Theo is a sharp guy, and you can’t always discern what he’s stating by one comment. You may benefit by going back a bit to see where he’s coming from. My experience is that Theo doesn’t put much cotton in the current CO2 theory, either.
ferd berple says:
July 1, 2011 at 6:53 pm
Actually, the AGW mantra is now “Climate Change” and in that one thing they’re right since a changing climate is definitely the status quo. So they go off half cocked claiming that the discipline is entirely theirs while ignoring the most basic tenants and methodologies involved, but I say: “Go for it, ye unwashed, politically imbued traitors of science and citizenship”. Their whole thesis is based on CO2 and when that’s proven to be even more untenable than it is now, they’ll become expert navel gazers instead.
Theo Goodwin says:
July 1, 2011 at 8:33 pm
Actually, a heck of a lot of science is done by blogging scientists. And engineers. And statiticians. And pissed off tax payers. You don’t have to have a degree in science to apply and understand the scientific method–hence the reason the more the AGW crowd throws their “science” at the public, the less it’s accepted.
It’s not hard or difficult, by any measure, to follow the next roll in the waves. Most models today are only good for extrapolating straight lines. Such endless slopes nature smirks at while it prepares its next big surprise. We see the big cycles and the small cycles endlessly in the Ice Ages, Ice Core records, ocean cycles, yearly cycles, etc. Anthropogenic burning of fossil fuels may be holding up the tent for now (or wemight be fooling ourself), but when the fuel runs out…. It will scacely be any different given the large swings in the big scales.
History will vindicate us.
We’re doomed!
(And, what is worse, if Brisbane keeps cooling down I’m going to have to move to – shudder- Cairns.)
From GISP2 site linked earlier in the article:
“ABSTRACT:
Greenland ice-core records provide an exceptionally clear picture of
many aspects of abrupt climate changes, and particularly of those
associated with the Younger Dryas event, as reviewed here.
Well-preserved annual layers can be counted confidently, with only 1%
errors for the age of the end of the Younger Dryas 11,500 years before
present. Ice-flow corrections allow reconstruction of snow accumulation
rates over tens of thousands of years with little additional uncertainty.
Glaciochemical and particulate data record atmospheric-loading changes
with little uncertainty introduced by changes in snow accumulation.
Confident paleothermometry is provided by site-specific calibrations
using ice-isotopic ratios, borehole temperatures, and gas-isotopic ratios.
Near-simultaneous changes in ice-core paleoclimatic indicators of local,
regional, and more-widespread climate conditions demonstrate that much
of the Earth experienced abrupt climate changes synchronous with
Greenland within thirty years or less. Post-Younger Dryas changes
have not duplicated the size, extent and rapidity of these
paleoclimatic changes.”
Indeed, 10-15C temperature swings over 500 yr periods are common before the settling in of the Interglacial.
Look at the GISP2 data.
Climate change is in written and geological history, so in ice cores also. Models are GIGO!
Theo Goodwin says:
July 1, 2011 at 8:28 pm
However, looking at graphs of older times and recognizing that they resemble graphs of present times is only a beginning. You may choose to take that beginning and create some science upon it. But scientific hypotheses are far more sophisticated than that. Take Kepler’s First Law as an example. It states that all planetary orbits are ellipses that have the sun at one of the foci. It organizes the data. All observations of planetary orbits from Earth should confirm that the planet in question is travelling in an ellipse with the sun at one foci. How can you get something like that from the fact that there were patterns in previous inter-glacials? Ancient astronomers knew of many patterns in the movements of planets, but they could explain diddly and predict diddly.
The first step in any science is observation. One of the simplest observations is that something is happening repeatedly, that observation is made by noting that repetition and reporting that you would expect a further repetition. Then observing the repetition. You can use any synonyms you want for that reporting – extrapolation, forecasting, prediction, experience….. but that first observation of a cycle is the foundation of the science of why that repetition takes place. However, although knowing ‘why’ may make you feel superior but it doesn’t change the forecast. The old fisherman knows when the tide will rise and how high its likely to be today this season with the wind, but knows not a lot about gravitation, fluid flows and Coriolis forces. Does that make a scientist better at forecasting the next tide?
This post is highlighting the type of response that an old fisherman would make to a youngster seeing the sea and the tide coming in for the first time and running about saying that the world is going to flood. And your response is like the youngster saying to the fisherman “what do you know? You are not modeling and really forecasting tides using science; you are just extrapolating from the past – this time it will be different! The world is going to be flooded!!”
James Sexton says:
July 1, 2011 at 8:36 pm
Same to ya’. 🙂
As a total neophyte in these matters, I dare to ask why the Greenland Positive Degree Day Trends (Jason E. Box’s web pages at http://www.meltfactor.org/blog/) seem to have had an spectacular increase only since around 1998, the Super El Nino year, while increasing only modestly from 1840 to around 1930 and descending from around 1930 to around 1998, as well as how this relates to anthropogenical warming. I have also put these questions at Jason Box’s blog).
Thanks for whatever answer.
(In the wake of NikFromNYC’s post of July 1, 2011 at 4:52 pm, and http://www.skepticalscience.com/10000-years-warmer.htm article)
Tend to think of this “reconstruction” (based on O18/O16 I presume as “horse pucky”.
Having done an MS Thesis on “Heat Transfer in a Packed Bed” and being familiar with “thermal waves” through solids, I find this to be interesting…
Compare 1:44 in the vimeo with GISP2. It’s obvious there IS no comparison.
Excuse me for being a bit “simplistic”. But the “purely mechanical” way of determining surface temperature based on the “thermal wave” seems PDG (pretty darn good).
You decide..
Two sets of “scientists”. Two results. Which is true? Which passes the “quality assurance” muster.
I personally like this one, the blue line that is. Historically it looks like there is no place to go but down and 8 deg C is quite a drop:
http://www.brighton73.freeserve.co.uk/gw/paleo/400000yearslarge.gif
There is a famous quote from Einstein …
“Insanity: doing the same thing over and over again and expecting different results.”
The converse should also be true ..
“Insanity: doing different things but expecting the same results.”
There are any number of causes for the previous changes. Rather surprisingly, as shown above, many of the past spikes had a similar time before they reached the peak. However, we know that there is at least one factor that is clearly different not than for any of the previous spikes – a very significant spike in CO2. This makes it questionable to expect this spike to be like the previous spikes.
Furthermore, this statement is telling:
“… there were several places in the record that looked very much like the sharp spike in temperature we’re experiencing now…”
There are many little spike; many large spikes. There are slowly rising spikes and rapidly rising spikes. Any time data is selected by “looks”, there is a strong possibility of introducing bias. There should be some clear criteria for selecting data, and for determining the length and rise of the spike. To me, even the spikes that were selected do not show any particular time to maximum.
Anyone who wants to bet on “what’s next” regarding the global temperature can find 14 bets available on Intrade at https://www.intrade.com/v4/markets/?eventClassId=20
BFL says:
July 1, 2011 at 9:40 pm
Yes, that was interesting. “We made ourselves a very bad experiment: We started meteorology at the coldest point in 10,000 years”.
Max Hugoson says:
July 1, 2011 at 9:37 pm
Oops, 4th of July pre-LIA fever. That was your vimeo video link for my above post.