In Which I Go Spelunking …

Guest Post by Willis Eschenbach

In my usual peripatetic wandering around the web, I came across an interesting paper called “Millennial- and orbital-scale changes in the East Asian monsoon over the past 224,000 years”, in Nature Magazine (subscription required), 28 Feb. 2008 , with Supplementary Online Information.

The paper uses “speleothems” to estimate past climate conditions. Speleothems are  secondary mineral deposits formed in caves. Stalactites and stalgmites are speleothems, and they come in a wide variety of sizes and shapes. Here’s a photo of some speleothems:

Figure 1. Speleothems in a New Zealand Cave.

What can we learn from the speleothems?

The authors used the speleothem data from two caves in China to investigate the climate changes over the last two glacial periods, a quarter million years or so. Being more interested in the recent past, and noticing that one of the datasets extended up to the year 1490, I decided to see what speleothems could tell us about the temperature changes in more recent times. So I got a large group of speleothem records from the NOAA Paleoclimatology web site.

I wasn’t interested in what happened thousands and thousands of years ago, so I got all of the long records that covered all or part of the period from the end of the last ice age to the present. This gave me 20 records.

The speleothems give us a record of what is called the “delta oxygen 18” (∂18O) value. This value is related to the temperature. The paper does not give the associated temperature values, so I converted them using the relationship described here as:

This is based on the average d[delta]18O/dT relation in modern precipitation (~0.6‰ °C-1), and the water-calcite fractionation that accompanies speleothem deposition (~-0.24‰ °C-1).

Decoded, this means that the change in temperature is equal to the change in ∂18O divided by (0.6 – 0.24), or ∂18O/0.36. Using that relationship, I calculated the temperatures from the various speleothems, and graphed them all with no further adjustment.

Figure 2. Raw data from 20 speleothem records. All of them have been converted from ∂18O using the relationship Temperature = ∂18O/-0.36. Black line is a 200-point Gaussian average. Different records are different colors.

While this was interesting, it appeared to me that the various records were likely not vertically aligned quite properly. After all, there is no a priori reason to think that they would all fit together, since they were simple anomalies (data minus average of that data) over different time periods.

So how to adjust them? There are several methods that are used to make this kind of adjustment to temperature anomalies for the global temperature records. GISS takes an average of two records in the area where they overlap, and adjusts on that basis. That was possible here, but seemed inaccurate. GHCN, on the other hand, uses one type of “first difference” method. However, their method requires that all of the datasets be on the same basis (annual, monthly, etc.), where in this case the measurements are at various random times that differ between datasets.

After some thought, I realized that I could use “first differences” in another way. The “first difference” is a new dataset that is made by calculating the difference between successive datasets. For example, if the dataset is {1, 2, 4, 8, 10}, then the first difference of that dataset is {(2-1), (4-2), (8-4), (10-8)}, or {1, 2, 4, 2}. This represents the differences between the points in the original dataset.

I realized that the standard deviation of the first difference is a measure of how well the various datasets fit together. (Standard deviation, “SD”, is a measure of how scattered the data is.)

So to adjust them, I first combined all of the 20 speleothem datasets into one single large dataset. Then I took the first difference of that single dataset. I measured the SD of the first difference data.

Then I adjusted each of the individual speleothem records by moving it slightly upwards and downwards, and used the increase or decrease of the SD to indicate which way it should be moved. I repeated this until the match was not improved by further testing and moving of the individual datasets. The result is shown in Figure 3.

Figure 3. Adjusted data from the same 20 speleothem records. All of them have been adjusted vertically to give the best fit. Black line is a 200-point Gaussian average.

This has improved the accuracy of the reconstruction. This is shown by the greater vertical range of the Gaussian average line.

So, what does all this mean? Heck, I don’t know, I’m investigating, not drawing conclusions. A few comments, in no particular order:

•  As is shown in the Greenland ice core records, we are currently at the cold end of the Holocene (the current interglacial).

•  Recent phenomena (Roman Warm Period, Medieval Warm Period, Current Warm Period) are scarcely visible at this scale. So much for the “uprecedented” nature of the recent rise.

•  The polar bears are not in any danger from the recent rise.

•  What’s up with the big jump and drop about 12000 years ago? I have not seen that in the ice core records, but it is present in these speleothem records from around the planet. [Update] A number of people have pointed out that this is almost certainly the “Younger Dryas” event. I hadn’t noticed it in the Vostok record, but a closeup of that record shows it.

•  The amount of the temperature change depends on the coefficient used to translate from d18O to temperature. So the numbers are likely in the right range, but may be somewhat too large or too small.

Anyhow, that’s my thoughts about what I’ve found out, I welcome yours. I continue with the investigation. It strikes me that I may be able to adjust the conversion factor (d18O/T) to see if that improves the fit of the data … should be interesting. Onwards …

DATA:

The caves used in this study were:

Cave, Location

Borneo_sch01, Borneo

Borneo_sch02, Borneo

Buckeye, Central US

Chilibrillo, Panama

Cold_Air, South Africa

Crystal, Midwest USA

Dayu, Central China

Dongge, Eastern China

Dongge04, Eastern China

Dongge05a, Eastern China

Heshang, Central China

Liang_Luar, Indonesia

Lianhua, Southern China

Lynds, Tasmania

Mystery, Midwest USA

Sanbao08, Central China

Sanbao10, Central China

Soreq_Bar, Israel

Spannagel, Austria

Venado, Costa Rica

In two cases, where there were several speleothem records from the same cave analysed by the same investigators, I have combined them into a single longer record. Data from different studies of the same cave have a year (e.g. “08”,”10″) appended to the name.

I have posted the data I used, along with the R file that I wrote to analyze the data, as a zip file here. Enjoy!

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Ray
May 26, 2010 3:56 pm

Simple questions…
Is the Oxygen 18 deposited at the same rate and manner in all those caves? Are all the caves have the same temperature, humidity, etc characteristics? Can we really put them all in the same pot (or plot!)?

May 26, 2010 4:02 pm

The Younger Dryas stadial, also referred to as the Big Freeze,[1] was a geologically brief (1,300 ± 70 years) cold climate period between approximately 12,800 and 11,500 years ago (between 10,800 and 9,500 BCE).[2]
http://en.wikipedia.org/wiki/Younger_Dryas

Al Gore's Holy Hologram
May 26, 2010 4:05 pm

THIS is open source science! Congrats!

Mike Davis
May 26, 2010 4:15 pm

Your “Bounce” could be reated to the “Younger Dryas”. The actual numbers wil in the end be guesses like in the rest of the Paleo research. Just knowing the Cyclic pattern is obvious in the historic record from all those location shows the Polar Bears are probably better able to adapt than we are to the coming cold!
The long term trend is still down!

Pat Moffitt
May 26, 2010 4:18 pm

.
• What’s up with the big jump and drop about 12000 years ago? I have not seen that in the ice core records, but it is present in these speleothem records from around the planet
The Younger Dryas?

Michael D Smith
May 26, 2010 4:19 pm

What do numbers to the right of zero on the X axis mean?

Dr A Burns
May 26, 2010 4:19 pm

Willis,
The NOAA link includes this:
“Smith et al. 2006 500-year Northern Hemisphere Speleothem Temperature Reconstruction in Text or Microsoft Excel format. ”
When plotted, this shows what looks like an average of about 6 degrees warming over the past 400 years, with a slight fall in recent years. Any comments ?

thingadonta
May 26, 2010 4:25 pm

I think the big T difference 12,000 years ago is the Younger Dryas event isnt it? Nbodoy knows for sure why it occurred, other than the polar bears didnt seem to mind.

Ralph Woods
May 26, 2010 4:29 pm

Just an armchair observer – it seems like temperature over very long periods seeks some stability point. Sort of like a pendulum swinging back and forth and then finding its zero point.

Martin Elphinstone
May 26, 2010 4:30 pm

Thanks for the analysis Willis,
You ask
“What’s up with the big jump and drop about 12000 years ago? I have not seen that in the ice core records, but it is present in these speleothem records from around the planet”
Check out (also at the NOAA site):
http://www.ncdc.noaa.gov/paleo/abrupt/data4.html
Looks like the Younger Dryas to me …
Have you split your data set into northern and southern hemisphere sites and analysed separately? May be too few of southern hemispehere sites to be meaningful though.

MikeC
May 26, 2010 4:52 pm

Willis says
“Indeed, that is the question … however, I don’t know the answer. But the general coherence of the various sites indicates that we are measuring something in common.”
Shame on you Willis, you should know the answer to this… the answer is that none of the questions are relevant because the oxygen isotopes did not form in the cave

May 26, 2010 4:54 pm

What’s up with the big jump and drop about 12000 years ago? I have not seen that in the ice core records, but it is present in these speleothem records from around the planet.

Maybe not exactly at 12k, but coming out of the last glacial I recall some proxies show such a pre-optimum bump or spike.
In the IPCC first assessment WGI, fig 7.2.1 (b) there is a bum between -9k and -10k. I thought it was elsewhere also. Not in ice core? Perhap sediment?

Drew Latta
May 26, 2010 4:54 pm

If I learned anything from my Glacial and Pleistocene Geology class is was that del-18O is also dependent on ice volume. Therefore one has to assume a volume of ice locked up in the polar regions to make an estimate of temperature. This is because 18O is preferentially left behind in the ocean when water evaporates. The del-18O value increases for time periods with lots of ice and decreases when ice melts. There is probably a bunch of error involved with estimating ice volume.

Gary Pearse
May 26, 2010 4:57 pm

The depth below surface of the caves must give differing temps, certainly of the range shown in the graphs. Is there any adjustment for this?

Wayne Delbeke
May 26, 2010 5:10 pm

Off topic but the Brits who visit this site might like to read this reference on Tony Blair and his income from consulting on Global Warming.
http://www.thisislondon.co.uk/standard/article-23838369-tony-blair-to-earn-millions-as-climate-change-adviser.do
Thank you for the information, another page to bookmark.

Gary Pearse
May 26, 2010 5:13 pm

Willis – the nanodiamonds from impact seem “rich”. Profitable kimberlite diamond deposits vary from as low as 0.15 carats/ton to rich deposits with 1 to 2 carats/ton. Now a carat is 1/5th of a gram and a gram per tonne is 1 ppm or 1000ppb, so a very rich diamond deposit at, say 2 carats/ton is 400ppb. The 1370ppb you report is a large concentration – were it not nanodiamonds, this would cause a worldwide staking rush to rival the klondike. Actually that “grade” of nanodiamonds could even be of interest as a polishing medium.

Gail Combs
May 26, 2010 5:14 pm

1.
Ray says:
May 26, 2010 at 3:56 pm
Simple questions…
Is the Oxygen 18 deposited at the same rate and manner in all those caves? Are all the caves have the same temperature, humidity, etc characteristics? Can we really put them all in the same pot (or plot!)?
__________________________________________________________________________
Are all the caves have the same temperature, humidity, etc characteristics?
In a word no. The caves in Southern Indiana are at 54.5F, caves in Texas, like Sonora are around 70F and dry. The caves in England, like Wookey Hole are a “bit damp” (better bring the scuba gear or practice holding your breath)
The cave temperature is generally the average temperature for the location unless you run into something strange like Crystal Cave of Giants in Mexico where the heat is “like a blast furnace”

May 26, 2010 5:22 pm

Other sources like the Greenland and Vostok ice cores show the same gradual cooling over the past 10K years:
click1 [Keohane]
click2
click3
click4
click5
During the recent geologic past the planet was cold much more often than it was warm.

May 26, 2010 5:26 pm

Apparently lack of Mammoth poop, due to over hunting by early Americans is another reason for the Younger Dryas. (SEE http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo877.html)
Of course based on the quality of this report i wouldn’t rule out ET as another probable factor.

Dena
May 26, 2010 5:29 pm

It has always troubled me that all of the warming periods except the one we are currently in have a very pointed peak when it comes to temperature. The current one has a flat top instead of a peak. Either something is very special about this warming period and past history is not useful or we have a problem in our current measurements. The data you present indicates we may have a problem with current measurements. This could be ground breaking.

May 26, 2010 5:33 pm

Dena, the flat top on the charts may be a function of the number of data points [including proxies], which are much more numerous in the Holocene.

DesertYote
May 26, 2010 5:35 pm

To me, the graph looks a lot like the ringing of an ECL circuit going from a low to a high. That would indicate some negative feedback mechanisms.

John F. Hultquist
May 26, 2010 5:36 pm

Ralph Woods says:
May 26, 2010 at 4:29 pm
Just an armchair observer – it seems like temperature over very long periods seeks some stability point. Sort of like a pendulum swinging back and forth and then finding its zero point.
Neither stable nor zero. The first does not seem to happen and the second better not. Other than that . . .

DesertYote
May 26, 2010 5:43 pm

Willis Eschenbach
May 26, 2010 at 4:38 pm
“Indeed, that is the question … however, I don’t know the answer. ”
Are you still using that dated “Scientific Method” thing? Get with the program. The correct answer is, “Its man’s fault, and its worse then we thought!”

Dr A Burns
May 26, 2010 6:01 pm

Willis,
Sorry, .6 not 6.

John F. Hultquist
May 26, 2010 6:21 pm

The following NOAA link has a chart of temperatures from several sources back to -20,000 years. It also has this statement:
In addition, there was probably a short-lived period of particularly high freshwater flux about 13,000 years ago that is not shown in this figure, resulting from a large discharge of freshwater from a glacial lake in North America.
http://www.ncdc.noaa.gov/paleo/abrupt/data4.html
Above that it mentions the flow of water to the North Atlantic via the St. Lawrence River.
I do not see mentioned the flow out the Mohawk River drainage of NY State, nor that down the Mississippi R., nor of the Missoula Floods. I suspect there are many other sources world wide during those same times that brought cold fresh water and ice to the rising oceans. I’ve not found a summary source nor good dates.
I think it odd that the quoted source used the singular ‘lake’ and not the plural ‘lakes’.

MattN
May 26, 2010 6:38 pm

So, what exactly does “we are currently at the cold end of the Holocene” mean?
Historically, what’s next? Up or down? The word “end” in that sentence indicates to me the Holocene is about to end. Correct?

Rick K
May 26, 2010 6:40 pm

Willis,
Thanks! Just… Thanks.
This is the kind of information that makes Watts Up With That such a great site! It’s such a great place to learn all sorts of things. Like the word “speleothems”! That was a new one on me.
Many thanks for your efforts, and of course, to Anthony and the mods.

LiamW
May 26, 2010 6:44 pm

Always use Google Scholar to check for pdf files.
http://dky.njnu.edu.cn/geoguanli/edit/UploadFile/200822914847689.pdf

Jimbo
May 26, 2010 6:47 pm

Some speculate that the cooling of the Younger Dryas was caused by melt-water from the abrupt earlier warming. I don’t know so I will remain sceptical.
http://www.ldeo.columbia.edu/res/pi/arch/examples.shtml
http://www.ace.mmu.ac.uk/resources/gcc/5-3-2-1.html
http://www.bbc.co.uk/dna/h2g2/A760240

DB
May 26, 2010 6:54 pm

John Hultquist wrote: “I think it odd that the quoted source used the singular ‘lake’ and not the plural ‘lakes’.”
The lake they were referring to is Lake Agassiz.
http://en.wikipedia.org/wiki/Lake_Agassiz
“Lake Agassiz was an immense glacial lake located in the center of North America. Fed by glacial runoff at the end of the last glacial period, its area was larger than all of the modern Great Lakes combined, and it held more water than contained by all lakes in the world today.”

May 26, 2010 6:58 pm

MattN,
I think Willis meant this. The start of the Holocene had higher average temps. We’re at the colder end of the chart.
I don’t think Willis meant the Holocene is about to end. We don’t know that. But it’s possible.

John F. Hultquist
May 26, 2010 7:10 pm

DB, I agree they likely meant Lake Agassiz but still it didn’t just drain out the St. Lawrence River nor all at once.
http://www.eeescience.utoledo.edu/faculty/Fisher/Fisher-%20Chronology%20of%20glacial%20Lake%20Agassiz%20meltwater%20routed%20to%20the%20Gulf%20of%20Mexico.pdf
And it was not the only lake contributing to the northern oceans.

rbateman
May 26, 2010 7:19 pm

The end of the Holocene is inevitable if one draws on full geologic history as a guide, Smokey.
I just don’t want to witness it.
I’m guessing the 2nd low in the graph is the time of the grassland Sahara.
Extend the graph back another 5-10,000 years should take it to the end of the Laurnetide.

Richard Hill
May 26, 2010 7:30 pm

Seems a shame so few southern hemisphere records. WRT Australia, would it be possible for the CSIRO to put more effort into collecting this type of raw data? Perhaps the resources they put into computer modelling could be diverted. The CSIRO might get more original multi-cited papers out of SH data collection, since they have better access to the study areas. In the computer modelling side the CSIRO is competing with huge resources from other countries. Much less chance of ground breaking multi-cited papers. Can anyone suggest a person with influence who could be contacted with these thoughts?

David Davidovics
May 26, 2010 7:40 pm

“This is open source Science”
ALL SCIENCE IS OPEN SOURCE.
Anything that is not open source is not science, don’t let any PhD tell you otherwise.

Michael
May 26, 2010 7:45 pm

Complacent Liberal Media Coverage of the Gulf Oil Spill

agimarc
May 26, 2010 7:50 pm

The Younger Dryas event as discussed earlier may have something to do with a large impact on the North American ice sheet. As it turned things cooler for a millennia, perhaps it was the event that truncated the expected post-glacial spike. That cooling and the death of the mega-fauna in North America is consistent with the after effects of a large impact.
There was also a large post-glacial lake that spilled in the Western US – glacial Lake Missoula – that formed and broke many times, scouring the land down to the bedrock.
The 18O shows up in the rocks courtesy of the water that preciptates and deposits the rock that forms the stalagmites / stalactites in the caves. All the cave rock is water-based; either cut or depositied via the action of water over an extended period of time.
The most interesting thing about the analysis is the right side of the graph showing our slow (perhaps not so slow) and accelerating move toward the next glacial cycle. At some (perhaps all) levels, that tends to bum me out.

dp
May 26, 2010 8:07 pm

That bump would have been around the time Lake Missoula drained across Idaho, Washington, and Oregon, leaving us the Channeled Scablands among other things. It left an incredible place to marvel at and to imagine about the scale of it. It’s not often you see erratics the size of houses out in the middle of a high prairie.
http://wapedia.mobi/en/Glacial_erratic

Al Gored
May 26, 2010 8:16 pm

Another great analysis, and another piece of the puzzle from an unexpected place.
And this is very interesting:
“These diamonds provide strong evidence for Earth’s collision with a rare swarm of carbonaceous chondrites or comets at the onset of the Younger Dryas cool interval, producing multiple airbursts and possible surface impacts, with severe repercussions for plants, animals, and humans in North America.”
Always wondered why the Younger Dryas was such a sudden event and something like this could theoretically explain it.

anna v
May 26, 2010 8:27 pm

Willis Eschenbach says:
May 26, 2010 at 7:44 pm
rbateman says:
May 26, 2010 at 7:19 pm
The end of the Holocene is inevitable if one draws on full geologic history as a guide, Smokey.
Well, there was a time when there were no regular ice ages. Then regular ice ages started. Someday, I assume that regular ice ages will end … so I would hardly call another ice age “inevitable”. “Very probable”, sure, but inevitable, no.

Well, as the energy environment of our planet has not changed since the ice ages started , no new planets, no great sun energy variation, … I would vote for inevitable.
Sitting by the shore and watching waves coming in, after one recedes it is inevitable that the next one will come in. Not that the sea has not been calm or will not be becalmed again, but in the time frame watched the boundary conditions are such that the next wave is inevitable.

MikeC
May 26, 2010 8:29 pm

Willis says
“Well, yeah, but since the isotopes presumably formed in very different parts of the planet, and different parts have different temperatures, I would assume that the relationship d18O/T would not necessarily be the same around the world.”
Let us all remember that you used… ahem… anomaly

bruce
May 26, 2010 8:30 pm

how do they determine date in this study?

Gail Combs
May 26, 2010 8:33 pm

MattN says:
May 26, 2010 at 6:38 pm
So, what exactly does “we are currently at the cold end of the Holocene” mean?
Historically, what’s next? Up or down? The word “end” in that sentence indicates to me the Holocene is about to end. Correct?
___________________________________________________________________________
That is a question open to a lot of debate.
1974 CIA Document on the Global Cooling Scare
Ice Ages are cyclical in nature and consist of approximately a 90,000-year glacial period followed by a relatively brief warming peak for 10,000 to12,500 years, called interglacials… Investigations indicate interglacials never extend beyond 12,500 years nor has the period ever been less than 10,000 years…. That this will occur within the next 2,500 years they are quite positive; that it may occur sooner is open to speculation….”
Ice Ages Confirmed: The Milankovitch theory
NASA: Intervals fell exactly where Milankovitch said they would
Past Climate Cycles: Ice Age Speculations
Sorry to ruin the fun, but an ice age cometh
In the middle of this presentation
is a graph with the current and other interglacials overlaid that is interesting to look at.
From Woods Hole Oceanographic Institution:
Abrupt Climate Change: Should We Be Worried?
Milankovitch Hypothesis Supported by Precise Dating of Coral Reefs and Deep-Sea Sediments
Extremist view:
Physicist Vladimir Paar: mankind needs to start preparing for the ice age
“The reality is that mankind needs to start preparing for the ice age. We are at the end of the global warming period. The ice age is to follow. … [W]e do not know precisely when it could start – but soon.”
The argument is over exactly what is meant by “soon” 10, 100, 1000 years or the 2,500 years max stated in the CIA report. Some reports even suggest we missed the change to an Ice age this time around and the earth will stay warm for another entire cycle.

Gail Combs
May 26, 2010 8:42 pm

Richard Hill says:
May 26, 2010 at 7:30 pm
Seems a shame so few southern hemisphere records. WRT Australia, would it be possible for the CSIRO to put more effort into collecting this type of raw data? Perhaps the resources they put into computer modelling could be diverted. The CSIRO might get more original multi-cited papers out of SH data collection, since they have better access to the study areas. In the computer modelling side the CSIRO is competing with huge resources from other countries. Much less chance of ground breaking multi-cited papers. Can anyone suggest a person with influence who could be contacted with these thoughts?
_________________________________________________________________________
I do know that Australia and South Africa have caves since I have been caving with people from both countries. I wonder if speleothem studies could be under taken if suitable caves can be found. Ships logs are another source of information for that area.

Pete Hayes
May 26, 2010 9:04 pm

“I have posted the data I used, along with the R file that I wrote to analyze the data,”
Willis!!!! That is not the correct method! Someone may try to “Prove your work is incorrect”. Off to the CRU for some lessons in Methodology! 😉

Flask
May 26, 2010 9:09 pm

“Well, there was a time when there were no regular ice ages. Then regular ice ages started. Someday, I assume that regular ice ages will end … so I would hardly call another ice age “inevitable”. “Very probable”, sure, but inevitable, no.”
Just guessing, but the earth might be susceptible to regular ice ages until Antarctica moves away from the South Pole, millions of years from now. That’s when sea level will rise to higher than it is now. It will drop during the glacial periods, and come back up to about present levels in the interglacials.

pat
May 26, 2010 9:26 pm

O/T apologies but we have missed another bullet:
Kansas City Star: EU Commission backs off on higher CO2 emission goals
Hedegaard was presenting a report indicating that conditions for a 30 percent move “are clearly not met,” a point not included in a draft which was seen by the German news agency dpa on Tuesday…
http://www.kansascity.com/2010/05/26/1972982/eu-commission-backs-off-on-higher.html
yesterday Ben Webster from UK Times jumped the gun:
Australian (from UK Times): Ben Webster: Europe’s bold move on climate
EUROPE was tipped to introduce a new plan overnight to combat global warming, committing it to the world’s most ambitious targets.
The surprise plan proposes a massive increase in the target for cutting greenhouse gas emissions in this decade…
http://www.theaustralian.com.au/news/world/europes-bold-move-on-climate/story-e6frg6so-1225871740545
as did Bloomberg:
Carbon Rises as EU Outlines Steps Toward Tougher Climate Goal by Ewa Krukowska and Mathew Carr
“The EU carbon price may double under a 30 percent target, according to the statement citing Michael Wilkins, S&P’s global head of carbon markets”
http://www.businessweek.com/news/2010-05-26/carbon-rises-as-eu-outlines-steps-toward-tougher-climate-goal.html
phew!

rbateman
May 26, 2010 9:38 pm

anna v says:
May 26, 2010 at 8:27 pm
Extending the geologic time-frame out another 3 billion years should follow the last 3.5 billion years.
Simple decay of higher order to lower. Another snowball Earth or two in between.
Until the Sun expands and cooks the planet prior to itself conking out some few billion years further.
Nothing to do to prevent geologic-scale climate change…except invent Warp Drive and get outta here.

Bill Illis
May 26, 2010 9:39 pm

I have a couple of charts showing the transition out of the ice age from the Greenland and Antarctic ice cores which might help this a little.
http://img38.imageshack.us/img38/9509/transitioniceagegrlndan.png
http://img260.imageshack.us/img260/8371/transitioniceageco2.png
One thing is that the Northern Hemisphere has more up and down variability in the ice ages (the Younger Dryas was only one of about 16 different significant up and/or down events, (the Younger Dryas was not as important as the Older Dryas for example and the Younger Dryas is really being used for its “scare factor” by richard Alley and the like).
The bigger drop in the following chart is actually the Older Dryas at 14,500 years ago, not the Younger at 12,800 (also note that the temperatures are not calibrated properly in this chart, the temp change – from Richard Alley – should only be half as much).
http://www.wunderground.com/education/GISPIItemp.gif
Third, on the dO18 isotopes from the speleotherms, Paul Dennis would note that regional precipitation changes can have a big affect on the isotope measures so that has to be taken into account. I would say we should just use them as they are and say they give us a pretty good measure of temperature changes in this region. The formula used by Willis here of Temp = do18/0.36 is probably off a little and should be more like Temp = do18 / 0.45 for this latitude and the fact that it is not really close to the ocean. For high latitudes like Greenland and Antarctica, one can use 0.90 or so ie, each 1.0%% is close to 1.0C.

rbateman
May 26, 2010 9:44 pm

Flask says:
May 26, 2010 at 9:09 pm
Thought about the onset of the next glacial and the attendant sea-level drop.
The Alarmists have not even stopped to consider the effects of that one.
How much of a global temp drop would it take to sufficiently lower the sea level to incapacitate the Suez & Panama Canals?
The blues will be sung on 6 Continents as Global Trade takes it on the chin.

May 26, 2010 10:03 pm


Hm. Contemplating speleothems and the warm-and-fuzzy Ursus maritimus supposedly drowning in the unforgiving Arctic Ocean as the ice vanishes between his insulated feet, just what the hell happened to despatch the cave bear (Ursus spelaeus) some twenty-seven millennia ago?
No, don’t tell me. It was anthropogenic global real estate development.
Humans competing with them poor, furry, innocent children of Mother Nature for space in those caves.
Doubtless we’ll find evidence of that in analyses of the stalactites and stalagmites. The residua of early, primitive realtors “blockbusting” the poor critters out of their homes….

LightRain
May 26, 2010 10:32 pm

stevengoddard says:
May 26, 2010 at 4:02 pm
The Younger Dryas stadial, also referred to as the Big Freeze,[1] was a geologically brief (1,300 ± 70 years) cold climate period between approximately 12,800 and 11,500 years ago (between 10,800 and 9,500 BCE)
That coincides nicely with the dip at 10,000 BCE (12,000 YA); but what about the bigger dip at 13,000 BCE (15,000 YA)?

stan stendera
May 26, 2010 10:33 pm

Echenbach’s Hawk is apparently part bat since it flys around in caves.
ps. I like bats, most don’t.

Duster
May 26, 2010 10:42 pm

Willis,
The “dip” following the “hump” actually marks the Younger Dryas. What your chart shows is that the onset of the Holocene was interrupted by the YD and actually delayed by about two thousand years. That period is problematic to paleontologists and archaeologists for several reasons. Massive extinctions are taking place. As Firestone and some others have observed there is a “nanodiamond” horizon marking the beginning of the event, but what is less commonly discussed is that the YD is also marked by an enormous C-14 anomaly which collapses near 2,000 years into an apparent 500 or so. So, in addition to Firestone’s possible extraterrestrial strike there is also a phenomenal radiation event with a large increase in cosmic rays to trigger the formation of excess C-14. The event was apparently very short in duration as well. I have yet to see any convincing hypothesis for the cause.

May 26, 2010 11:07 pm


Duster writes of “…in addition to Firestone’s possible extraterrestrial strike there is also a phenomenal radiation event with a large increase in cosmic rays to trigger the formation of excess C-14. The event was apparently very short in duration as well. I have yet to see any convincing hypothesis for the cause.
Okay, so we may be looking at an event occurring outside our residential star system. Any residua of something cosmically catastrophic in the stellar neighborhood at that time?
Roger MacBride Allen and astrophysicist Eric Kotani (Yoji Kondo) published the novel Supernova in 1991 to explore the possible effects of a violent cosmic event within (astronomically) close range of Sol system. Major bad juju. Might something of a like nature have occurred to account for that “enormous C-14 anomaly” in the Younger Dryas?

May 26, 2010 11:09 pm

Hi WIllis,
one of the other useful conclusions which can be drawn from speleotherm data, (note spelling, I’m not a grammar nazi but it might save you some embarassment later) is that the MWP was a worldwide phenomenon. Speleotherm data from th southern hemisphere shows an upward blip around the MWP. There are some examples at co2sience.org of papers on New Zealand and South American speleotherms showing it.

Geoff Sherrington
May 26, 2010 11:12 pm

Willis, I wonder if these glow worm filaments have any involvement in making stalactites and if so, what effect their delta-O18 might have on the reconstruction?
I have not asked specific permission to use this URL, but do look at
http://www.glowworm.co.nz/photo-gallery.html

Al Gored
May 26, 2010 11:26 pm

Flask says:
May 26, 2010 at 9:09 pm
“Just guessing, but the earth might be susceptible to regular ice ages until Antarctica moves away from the South Pole, millions of years from now. That’s when sea level will rise to higher than it is now. It will drop during the glacial periods, and come back up to about present levels in the interglacials.”
Oh no. Can the UN do anything to stabilize the tectonic plates the way they are going to stabilize the global climate? No more than 2 C and 20 km should be the rallying call to save us. Perhaps a market for continental offsets and related derivatives could achieve this vital goal, with massive investments in research and monitoring by the IPCD. This will require sacrifices from the little people of course, whose sheer weight would clearly be the cause, and more global governance to address this coming global crisis.
But we must do it, for the children and the penguins.
I’m also deeply concerned about the sun. Its just a matter of time, and when it goes, the results could be catastrophic.

Al Gored
May 26, 2010 11:34 pm

Duster says:
May 26, 2010 at 10:42 pm
“Massive extinctions are taking place. As Firestone and some others have observed there is a “nanodiamond” horizon marking the beginning of the event, but what is less commonly discussed is that the YD is also marked by an enormous C-14 anomaly which collapses near 2,000 years into an apparent 500 or so. So, in addition to Firestone’s possible extraterrestrial strike there is also a phenomenal radiation event with a large increase in cosmic rays to trigger the formation of excess C-14.”
It just keeps getting more interesting. But since those massive extinctions were quite selective, I wonder how/if this radiation effect could play into that?

May 26, 2010 11:40 pm

Concerning the Younger Dryas, there was recently a pseudoscientific study from Univ. of New Mexico, linking its temporary fall back to ice age conditions with mammoth extinction, which stopped farting methane. They allegedly produced 10 billions kg CH4/year before. Comparing this tiny amount against the mass of the whole atmosphere with its 5×10^18t, it was clear it is pure nonsense, just to keep the idea of “greenhouse gases” as the main climate driver. Methane probably dropped, since the ice cover expanded and rotting organic matter like grass or plants – the main source of methane – were suddenly limited. Can the author make similar common sense rebuttal like with the Silver lining thing?
http://content.usatoday.com/communities/sciencefair/post/2010/05/mammoth-extinction-triggered-climate-cooling/1

May 27, 2010 12:25 am

Hi WIllis,
one of the other useful conclusions which can be drawn from speleotherm data, (note spelling, I’m not a grammar nazi but it might save you some embarassment later) is that the MWP was a worldwide phenomenon. Speleotherm data from the southern hemisphere shows an upward blip around the MWP. There are some examples at co2sience.org of papers on New Zealand and South American speleotherms showing it.

Bruce of Newcastle
May 27, 2010 1:13 am

Concerning the Younger Dryas dip, there’s a good article on ‘Clovis culture’ in Wikipedia. Has the nanodiamonds and even “high levels of metal and magnetic spherules found deep inside the tusks and skulls of mammoths”.
If you are a mammoth I suppose having a comet land on you would ruin your whole day.
PS. no sign of William ‘Mr 5428’ Connolley in the history page.

P Solar
May 27, 2010 1:26 am

What do you see wrong with Younger Dryas event showing up in this data?
The whole thing seems to match existing dO18 studies elsewhere, although Antarctic cores seems less sensitive than both this data and GRIP (Greenland).
http://en.wikipedia.org/wiki/File:Epica-vostok-grip-40kyr.png
(I don’t trust wikipedia, especially posts by Connelly who is a AGW crusader who got defrocked as wiki admin for abusing his admin right, but this does seem representative and is the first link I found.)
This is an interesting corroboration of GRIP data from a physically and geographically different medium.
E. R. Thomas et al 2009
doi:10.1029/2009GL040104, 2009
We are using a temporal gradient of 0.5 ± 0.1 ‰ per °C to convert δ18O to temperature, based on the calibration between the δ18O with site temperatures from the European Centre for Medium Range Weather Forecasts (ECMWF) (1980–2005).
Seems to match your convertion , where do you get your water-calcite fractionation figure?

J Midgley
May 27, 2010 1:39 am

I don’t understand the temperature projections into the future. Am I missing something?

May 27, 2010 1:42 am

Thanks WIllis. You’re right, it seems to get spelled both ways, but there are about 10 times as many google hits for your spelling and only around 13000 for mine. I’ll use speleothem in future.
Cheers

Ken Hall
May 27, 2010 2:01 am

“Thought about the onset of the next glacial and the attendant sea-level drop.
The Alarmists have not even stopped to consider the effects of that one.
How much of a global temp drop would it take to sufficiently lower the sea level to incapacitate the Suez & Panama Canals?”
If global trade were to be significantly effected by this, then they would dig a channel however deep as would be required to keep that shipping lane open.
They are already increasing the capacity of this canal by making it wider.

May 27, 2010 2:07 am

J Midgley says:
May 27, 2010 at 1:39 am

I don’t understand the temperature projections into the future. Am I missing something?

Minus is BC, above 0 is AD.
Technically incorrect, in fact, because there never was a zero year. The calendar (retrospectively) goes from -1 to +1. Innumerate popes, and all that.

TomVonk
May 27, 2010 2:52 am

In that case, since you understand it, perhaps you can tell us what the change was, about a million years ago, that started the current series of regular ice ages. That way, we’ll know what to look at for what might end the current series.
AnnaV has probably her own idea .
.
My take on it is that we don’t know that anything significant changed 1 million years ago .
It is just an artefact because more or less reliable “climatic” data are younger than 1 million years and most of those that are used are actually even shorter (100s thousands of years) .
1 million years is really nothing at the geological scales .
What happened between 79 millions and 78 millions years ago ?
Were there glaciation cycles ? How many and how strong ?
In some kind of vaguely defined average this randomly chosen short period looks like relatively warm but would a .04 or even .1 ky oscilating signal be visible at all at a 100 million year scale ? At a billion year scale ?
Would there be much of it left at all anyway ?
Certainly not .
If we talk temperature , the only way to maintain a parameter in a narrow band of variation (what is what we observe since the Earth exists and here I talk billions of years) is to make it oscillate or to make it constant .
As a chaotic system is never in equilibrium and can’t be constant , the system must oscillate .
The frequencies may vary with time and they surely do but there certainly were pseudo periodical Ice age oscillations since the day when temperatures at the poles allowed formation of ice and that happened billions of years ago .
So yes , the next Ice Age is a certainty unless one supposes that the climate system suddenly stopped to oscillate and went in a divergent , non chaotic , unbounded mode what would be unprecedented in 4 billions of years .
If one expects that the principal frequencies vary smoothly with time , the next occurence will happen with a similar frequency like the last one – that is the argument AnnaV used and I tend to think the same thing too .

Ryan
May 27, 2010 3:10 am

Hi Willis,
Good work, but I notice that if I look at the Vostok ice-core data which Joanne Nove has kindly expanded on her website:
http://joannenova.com.au/global-warming/ice-core-graph/
You get excellent correlation of the graph shape but your graph is shifted some 2000 years to the right. This means that if the two graphs are at all coincident, then your graphs actually stop 2000 years before the ice-core data (which in itself stops some 2500 years before the present day. This means that your most recent data is actually not showing todays climate, but is in fact showing the climate from 5000 years ago. I would presume that this is because the water percolating into these caves from the surface actually takes thousands of years to make the journey.
What is interesting about your grpahs is they show a 2Celsius decline in temperature since the end of the last glacial. This is much more in line with the ice-core data of previous inter-glacials which show a gradual decline in temperature to the start fo the next glacial.

Mike Hollinshead
May 27, 2010 4:27 am

RE:
Willis Eschenbach says:
May 26, 2010 at 7:44 pm
rbateman says:
May 26, 2010 at 7:19 pm
“The end of the Holocene is inevitable if one draws on full geologic history as a guide, Smokey.”
Well, there was a time when there were no regular ice ages. Then regular ice ages started. Someday, I assume that regular ice ages will end … so I would hardly call another ice age “inevitable”. “Very probable”, sure, but inevitable, no.
Willis,
The explanation usually given for the beginning of ice ages is the closing of the gap between North and South America, restricting interchange between the Atlantic and Pacific Oceans.
So, unless someone blows up the Isthmus of Panama, it would seem that Ice Ages will continue 🙂
Mike

Mike McMillan
May 27, 2010 4:29 am

tallbloke says:May 26, 2010 at 11:09 pm
. . . one of the other useful conclusions which can be drawn from speleotherm data. . .

We might christen the temperature curves derived from speleothems “speleotherms.”
Perhaps we should enter Willis’ chart into Wikipedia. It’s every bit as colorful (and therefore authoritative) as their current Holocene temperature chart.

Rob R
May 27, 2010 4:53 am

Willis,
Nice posting but I have one significant issue with it. This is that the Vostok Ice Core does not contain a Younger Dryas aged reversal. The reversal in d180, temperature, and trace elements found in various Antarctic cores (much more detaiol is available from the Taylor Dome, Byrd, Dronning Maud Land, Dome Conchordia, Siple Dome and Dome Fuji cores) during the glacial-Holocene transition has been dated accurately. The event is officially known as the “Antarctic Cold Reversal (ACR). There is a heap of detailed work on this and I can provide references if you are interested.
If you go back further into the isotopic records from Greenland and Antarctica you will find that millenial-scale climate events over the respective ice sheets are out of phase (by about 1500 yrs or so) through almost the entire glacial period from about 100,000 BP to 10,000 BP. Antarctic events appear to take the lead in terms of timing. This pattern is also found in sea surface temperatures when the Southern Ocean is compared to the North Atlantic. The causes of this general pattern are still being hotly debated. The effects stretch to the periodic penetration of Antarctic bottom water as far north as Portugal in the North Atlantic.
If you wish to follow up on this field of study I would suggest you start with:
Ahn, J.; Brook, E.J. 2008. Atmospheric CO2 and climate on millennial time scales during the last glacial period. Science 322: 83-85.
Schmittner, A.; Saenko, O.A.; Weaver, A.J. 2003. Coupling of the hemispheres in observations and simulations of glacial climate change. Quaternary Science Reviews 22: 659-671.
Blunier, T.; Brook, E.J. 2001. Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period. Science 291: 109-112.
*Monin, E. et al 2001. Atmospheric CO2 concentrations over the last glacial termination. Science 291: 112-114.
The last gives a very nice comparison of the relative timing of the Antarctic Cold Reversal and the Younger Dryas. NB there is a fairly large literature relevant to the relative timing and intenssity of millennial-scale climatic events for both hemispheres.
Note that in the last few years the presence of the Younger Dryas has largely been debunked as far as the climate record in New Zealand is concerned, whereas (unsurprisingly) there is clear evidence for a cold event associated with the ACR in NZ (from speleothem records).
By the way I seem to recall reading a paper (from the Journal Geology I think) on widespread charcoal in North America relating to a potential comet or asteroid strike at the initiation of the Younger Dryas.
Cheers
Rob R

BBk
May 27, 2010 5:24 am

“Okay, so we may be looking at an event occurring outside our residential star system. Any residua of something cosmically catastrophic in the stellar neighborhood at that time? ”
Unless the comet strike changed the atmospheric properties to become more transparent to cosmic rays until the world could get itself back together?

anna v
May 27, 2010 5:33 am

Willis Eschenbach says:
May 26, 2010 at 10:33 pm
In that case, since you understand it, perhaps you can tell us what the change was, about a million years ago, that started the current series of regular ice ages. That way, we’ll know what to look at for what might end the current series.
I will go back to my dynamical analogy of the waves on the shore.
In that analogy, as a physicist, could I answer “what would end the current series of wavefronts”?
The answer is : a change in the energy inputs. For the wave fronts this change could take many ways: change in wind, change in cloud cover , change in currents.
In the case of the planetary system and earth itself, a change in orbits due to energetic interactions: getting into the range of different gravitational fields, a rogue planet entering the system, an asteroid hitting the earth, the sun turning nova, tectonic effects from internal energy changes, etc.
Your question reminded me of a Hodja story.
Hodja is an anatolian judge/mufti ( sometimes a clown) common in the folklore of Turks and Greeks who have originated in Anatolia.
Hodja was walking by a forest when he saw a man sitting on a thick branch of a tree and sowing it off on the wrong side. He spoke up: “my good fellow, be careful, you will have a bad fall” .
Before he reached the village he heard running footfalls and the wood cutter ran up to him and said: “Hodja, you are a great prophet, can you tell me when I will die”?
My answer would be, inevitably in the next eighty years.

May 27, 2010 6:23 am

Very interesting data. It compares well with oxygen isotope data (for a much more accurate chronology, compare it with the GISP2 data (Stuiver and Grootes, 2000) rather than the Vostock data which is not well dated. You can view the isotope curve for the past 17,000 years developed by Cuffy and Clow (1997) in the paper posted on my website– http://myweb.wwu.edu/dbunny/research/global/index.htm.
For a detailed view of the isotope record at the GISP2 data for the past 500 years, look at Fig. 33 in the same paper.
The big warming at about 15,000 years is the sudden, intense climate shift that marked the beginning of the end of the last Ice Age, and the cooling at 12,800 is certainly the Younger Dryas (12,800 to 11,500 years ago). The curve also captures the sudden cooling and warming from about 8200 to 8500 years ago. Note the large differences in the magnitude of the warming/cooling episodes compared to recent warming/cooling. The ice cores show huge changes in very short time periods (largest noted by other authors is warming of about 15 degrees F in only 40 years at the end of the Younger Dryas as compared to modern warmnig of 0.8 degrees per century.
The GISP2 core shows that the first 7,000 years of the Holocene (last 10,000 years) were warmer than present (but the polar bears survived it quite well) with cooling over the past 3,000 years. The past 500 years are particularly interesting because the isotope records shows a persistent cyclic of warming and cooling with an average 27 years (the same as the periodicity of the Pacific Decadal Oscillation).
Cave isotope records in Oman show an interesting correlation between delta 14C (which is a measure of production of radiocarbon in the upper atmospheric by incoming radiation) and oxygen isotope ratios between about 6,000 and 9,000 years ago (see figure 38 in the web paper). Looks like a strong solar influence of climate.

May 27, 2010 6:30 am

About the southern Hemisphere climate record—the Vostok core is not well dated so detailed correlations are difficult at best. However, the land record in New Zealand is very clear. Glaciers there responded to the Younger Dryas and left moraines dated at Younger Dryas at Birch Hill, Prospect Hills, and several other valleys. The idea that the Southern Hemisphere was out of phase with the Northern Hemisphere is at odds with this very real data. A paper now in press will detail all of this data.

May 27, 2010 6:43 am

Sorry, this Oxygen 18/Temperature correlation is “The King’s New Clothes”.
There is absolutely NO proof that this correlates with either “global energy balance” nor temperature.
Tropical thunderstorms increase the amount of O18, particularily along costal outfall areas.
This is about the only known “fact”. Extending it to “global temperature” or even atmospheric energy (overall) is a “stretch” or a “jump” which has no good basis.
“Tell a lie..often enough, loud enough…long enough..” You know the rest.
Max

juanita
May 27, 2010 7:00 am

we made a cave with speleothems for science. We used the crystal growing recipe on the bottle of Mrs. Stewart’s bluing, and we made several and layered them. We made them on alum foil with holes pricked in it, and we could shape the aluminum foil to resemble layers of rock. Every now and then we added new solution, and sometimes we added food coloring. That kind of showed when the application was made. We got stalagtites and stalagmites, some as big as a half inch. We had so much fun with that project we kept it around the house for the better part of a year, messing with it. We followed up with a trip to California Caverns up near Sonora – WHOA! We found that we had made a pretty good model in the kitchen.
Have a nice day Anthony – ttfn Juanita

KJ
May 27, 2010 7:09 am

Here’s some amazing pictures of speleothems
http://www.crystalinks.com/mexicocrystals.html
Mod- Unsure of how to code my link, quick tip?please

Steve Fitzpatrick
May 27, 2010 8:18 am

Willis,
Thanks for this very interesting work.
One thing that surprised me was that even though the data from different sites tells the same basic story, there does seem to be quite a bit difference in the range of temperature variation for different sites. I have read that the glacial/interglacial difference in temperature is expected to be much larger at high latitudes than in the tropics. Since the cave sites cover a range of latitudes, might the differences in temperature be related to the differences in latitude (with high latitude sites showing greater temperature variations than tropical sites)?

Hu Duck Xing
May 27, 2010 8:49 am

“Okay, so we may be looking at an event occurring outside our residential star system. Any residua of something cosmically catastrophic in the stellar neighborhood at that time? ”
What about an unprecedented Solar event? Collision with a large object possibly creating a massive flare?

Ed Murphy
May 27, 2010 8:56 am

Its worse than we thought, man caused the Younger Dryas… bad man, bad, bad bad, you shmuck!
http://www.cosmosmagazine.com/news/3460/did-megafauna-extinction-cool-planet
I think its highly possible there was a planet size comet captured in our solar system that came apart 25,000 years ago and it could have been producing the glacials by gravitational pull. Now that it came apart we might not have any more. Research the Taurids complex and surviving comet P2Enki. Harvard has a lot…
http://articles.adsabs.harvard.edu/full/seri/MNRAS/0251/0000636.000.html
http://stevepace.intuitwebsites.com/

William Roberts
May 27, 2010 9:00 am

I see that people here are “quick” learners. Not about actual science, mind you. This is the same type of “trick” that Michael Mann uses. To blindly say that the d18O signal in a speleothem is purely temperature is WRONG. I’ll give you the benefit of the doubt and chalk it up to ignorance, as opposed to a devious ploy. Many [snip] were up in arms about the tree rings and precipitation changing tree ring width – not just temperature – and now you’re doing it here!!! Too funny.
Your observation that the early Holocene was much warmer than present is seriously flawed based on your transfer function.
Readers here should be aware of the terrible science being employed here. Don’t blindly accept it.

Editor
May 27, 2010 9:29 am

Surely we are looking at what happened x years ago? We need to find out how long it takes water to filter through the rock to know when x actually was and then everything before that can be related to dated ice cores.
tonyb

Gail Combs
May 27, 2010 9:38 am

#
#
stan stendera says:
May 26, 2010 at 10:33 pm
Echenbach’s Hawk is apparently part bat since it flys around in caves.
ps. I like bats, most don’t.
_________________________________________________________________________
Bats eat mosquitoes, so whats not to like?
Perhaps Dr Mann should be spending that 1.8 million building and distributing bat houses to malaria ridden areas. At least that way someone would get some good out of the money. It would provide Green ECO jobs too!

Gail Combs
May 27, 2010 10:49 am

William Roberts says:
May 27, 2010 at 9:00 am
I see that people here are “quick” learners. Not about actual science, mind you. This is the same type of “trick” that Michael Mann uses. To blindly say that the d18O signal in a speleothem is purely temperature is WRONG. I’ll give you the benefit of the doubt and chalk it up to ignorance, as opposed to a devious ploy. Many deniers were up in arms about the tree rings and precipitation changing tree ring width – not just temperature – and now you’re doing it here!!! Too funny.
Your observation that the early Holocene was much warmer than present is seriously flawed based on your transfer function.
Readers here should be aware of the terrible science being employed here. Don’t blindly accept it.
_______________________________________________________________________
Willis is not asking us to “blindly accept it” He has an inquiring mind, took some already published data and had a look at it, and played with it for a bit. He thought it looked interesting and put it up at this website for the rest of us to look at, comment and critique. Seems pretty close to what science is supposed to be like, an open discussion about the data and given, time, money, equipment and expertise, reproduction of the results.
Willis even said:
“…So, what does all this mean? Heck, I don’t know, I’m investigating, not drawing conclusions…..
The amount of the temperature change depends on the coefficient used to translate from d18O to temperature. So the numbers are likely in the right range, but may be somewhat too large or too small.
Anyhow, that’s my thoughts about what I’ve found out, I welcome yours. I continue with the investigation. It strikes me that I may be able to adjust the conversion factor (d18O/T) to see if that improves the fit of the data … should be interesting. Onwards …”

You say the O18 should not be used to estimate temp. How about giving us some studies/papers that show it is a poor proxy???
This shows O18 used for sea temp studies: http://www.physics.ohio-state.edu/~wilkins/energy/Companion/E16.3.pdf.xpdf
Yes I know that is based on living animals sequestering the O18. So here is a paper that
seems to be using O18 in climate studies using speleothems.
“…Abstract
‘Clumped isotope’ thermometry is based on analyzing mass 47 in CO2 extracted from carbonates and uses the tracer mass 47 anomaly (Δ47). Δ47 is defined as the deviation of R47 from that expected for a random distribution of isotopologues and reflects a temperature dependent preference of 13C and 18O to create a bond with each other in CO2 or in the carbonate lattice. Being an internal characteristic of the carbonate mineral, it is independent of the isotopic composition of the water in which equilibrium precipitation of the carbonate occurs and can therefore be used to independently determine carbonate growth temperatures. This work provides a first examination of the applicability of ‘clumped isotopes’ thermometry to reconstructing the growth temperatures of speleothems, by examining the glacial/interglacial variations of the Δ47 values of speleothem carbonates from Soreq cave, Israel. The results indicate that the last glacial maximum temperatures were 6–7 °C colder than modern day temperature and a sample at 56 Ky BP was 3 °C colder than the modern…”
Glacial/interglacial temperature variations in Soreq cave speleothems as recorded by ‘clumped isotope’ thermometry

speleo PhD student
May 27, 2010 11:24 am

Dear Willis, I am afraid William Roberts is right on this. I am doing a PhD on speleothems and climate. The interpretation of d18O depends on many factors, and primarily on cave location. For instance, in monsoon regions, d18O usually shows precipitation amount through the “amount effect”: when there is more rainfall, your d18O values will be more negative, because the heavier isotopes rain out first… If you plot, for instance, Dongge cave record individually, you will see that the most negative values of the record (which you interpret as lower temperatures) will coincide with the Early Holocene, when it was really wet and warm.
Please don’t get me wrong. I support scepticism and open science. However, doing a bit more research before you start your analysis will dramatically enhance your credibility. I hope you see my point.
And, check climategate e-mails. Michael Mann is condemned even by his allies because of doing such poor analysis – like the one you did above. He used monsoon records as temperature proxies, in a very similar fashion.

Gail Combs
May 27, 2010 12:40 pm

#
speleo PhD student says:
May 27, 2010 at 11:24 am
Dear Willis, I am afraid William Roberts is right on this. I am doing a PhD on speleothems and climate. The interpretation of d18O depends on many factors, and primarily on cave location. ….
Please don’t get me wrong. I support scepticism and open science. However, doing a bit more research before you start your analysis will dramatically enhance your credibility. I hope you see my point.
___________________________________________________________________________
I was wondering about the rain fall dependency. However from the caves I explored, the spelothems were always wet on the bottom so although the rate of growth is related to the amount of rainfall and the width of the growth bands can be used to determine wet vs dry years, wouldn’t the O18 be dependent on how long it took for the water to move into and out of the water table into the cave?
What I find interesting is, even though there is the confounding, you get a strong signature of “something” common to all 20 data sets. Temperature? Temperature plus precipitation? Precipitation only?
It may not be what Willis was initially looking for but it is still worth seeing.

harvey
May 27, 2010 1:56 pm

speleo PhD student:
don’t bother arguing with these writers here. While claiming to be skeptics, they are really “antis” rather than skeptics. “Anti” anything that interferes with their Objectivist and Libertarian viewpoints that an individual should be able to do whatever they wish to do free from government and societal restraints.
Step on the poor slob in the gutter “he deserves to be there and I am better” is their motto. Ayn Rand would be proud.
There actually is no “science” reported here, just fabricated articles cherry picking data and written from their “anti” slant.
One wonders who is funding them for all their time as they seem very prodigious in the volume of crap they post.

Rob R
May 27, 2010 2:38 pm

Don Easterbrook
Who is the paper written by and which Journal is it going to be published in?

speleo PhD student
May 27, 2010 2:51 pm

Willis, did you plot the Dongge cave record individually? What do you see? Even better, plot all the monsoon records and also the records that are INTERPRETED AS RAINFALL IN THE ORIGINAL ARTICLE altogether (for instance, Soreq cave record). You will see that, in the “wet and warm” early Holocene, d18O will turn sharply NEGATIVE, and you interpret negative d18O as cooler temperatures for the rest of the records, don’t you? So, does d18O work as a temp proxy for the rainfall-proxy regions? NO. “Wet-and-warm” argument is NOT reflected by d18O. Wet makes d18O more negative, but warm makes it more positive! Show us monsoon records and non-monsoon records seperately, and everyone will get the issue.
The first thing you should do is to skim through all the original papers associated with the data sets, eliminate all the data sets in which d18O is interpreted as a rainfall proxy. And and and.. d18O is influenced also by seasonality of rainfall, did you know? Imagine, if you have a shift to more summer rainfall with the same total annual precip amount, wouldn’t you get higher values of d18O? Even if the temperatures do not change? You should also eliminate data sets for which this effect can be important. And you CAN NOT decide before reading the original papers.
I believe that Early Holocene was warmer and wetter than present in the Northern Hemisphere. But this is no argument against the current warming, because the reason for the Early Holocene warmth is very well established. It is the increased summer-time solar irradiance due to the state of Milankovitch cycles. And: If you attempt doing paleoclimatology without any knowledge of the Younger Dryas… I don’t know what to say…
The “warmists” out there, especially the ones at realclimate, are so happy when they see posts like yours. Your analysis is invalid and your claims are easily refutable using well-known facts. I am sorry, but you give skeptic community a bad name, with “works” like this. I can’t imagine Steve McIntyre doing this.

Editor
May 27, 2010 2:52 pm

Harvey said
“While claiming to be skeptics, they are really “antis” rather than skeptics. “Anti” anything that interferes with their Objectivist and Libertarian viewpoints that an individual should be able to do whatever they wish to do free from government and societal restraints.”
Wow Harvey you are certainly coming late to the party whilst wearing a blindfold if you believe that the nonsense you regurgitate here is a fair representation of the many and varied viewpoints of those who post on WUWT.
Why don’t you stick around, write something sensible, and get to know us a bit better THEN make a judgement.
Tonyb

May 27, 2010 2:54 pm

speleo PhD student,
Observe harvey like one of your speleothems. He is a typical example of a closed-minded, fact-free troll. We get them here on occasion.
Rather than contribute something worthwhile to the conversation, he makes completely baseless, false accusations on the internet’s “Best Science” site.
No doubt Harvey is taking a time out from his RealClimate echo chamber home to make his hit ‘n’ run drive-by comment.
I would just like for Harvey to tell me one thing: who is supposed to be funding me, and when will my check be in the mail?

May 27, 2010 3:12 pm

speleo PhD student,
I gave you a strange subject to consider, a species of internet troll, but you insist on sticking to your specialty.
OK then, have it your way. But don’t criticize Willis for writing interesting articles. Anthony is always looking for new articles — why don’t you write one for WUWT? I would look forward to the genuine peer review you would receive here.
You could tie in your speleo article with the low correlation that tree proxies have to temperature [you know, the same proxies that Michael Mann and Caspar Amman used to try and get rid of the MWP and LIA].
So you see, even seasoned experts often get it wrong, whether deliberately or through ignorance. My advice is that you should write that article right now, while you still know it all.

speleo PhD student
May 27, 2010 3:28 pm

@ Smokey: I am well aware that proxies are distorted by paleoclimate scientists as well, but bad science cannot be debunked by bad science. I wonder why people like Willis are so impatient just to “write” and to “reconstruct” something, when they could do much better with a little bit more effort and attention. Fighting back with bad science only makes the “establishment” more powerful, and in turn my life more miserable. I cannot defend Willis and support skeptic community (which I would really like to), if the products are this quality.
About the article: I’ll publish some formal ones first (I must). After obtaining the PhD and getting more independent, everything will be easier. I promise to return.

Jim Barker
May 27, 2010 3:39 pm

Perhaps these trolls are resentful about any cave-based research.
I thought it was a very interesting article and discussion.

Sam'l B.
May 27, 2010 6:44 pm

Thanks, Willis, for being honest about your fudge factors and assumptions.
Refreshingly Open Source science! 🙂

speleo PhD student
May 27, 2010 7:05 pm

Dear Willis, it is not safe for me to use my real name. Apologies for that.
Yes, I tried to lecture you, which was much needed. I don’t see why lecturing should be wrong, this is my area.
You still seem not wanting to understand the basics of this science. The correlation between “temperature” and “d18O in modern precip” is POSITIVE. Accordingly, in your text, you correctly found a value of +0.36 per mil d18O change for every degree celcius, after subtracting the deposition effect… This means, if you assume all other effects (amount effect, seasonality, precip source effect etc.) to be non-existent, you will observe 0.36 per mil more positive d18O for every degree C. This positive relationship is what we observe in all the ice core records as well, and all researchers in the field know this. This has nothing to do with caves, this is basic isotopic fractination. Spannagel cave record is a rare example of the reversed relationship, where the source effect plays a role (read the paper). And, monsoon records have their own story, through their own mechanism, which I explained above.
So, 1) if you assume an inverse relationship between temp and d18O, maybe you made a mistake. This is plain wrong. This is contrary to your very first calculation. 2) You cannot take Spannagel or Monsoon records as references for this assumption… Spannagel’s reasoning is through the “variable source effect”, due to a special geographical location, and temperature is only INDIRECTLY related to this and authors make use of that fact (read the paper). Therefore you cannot use this reasoning for all of your collected data.
Thanks for the discussion by the way. What I say is: study more before publishing.

speleo PhD student
May 27, 2010 8:14 pm

By the way, Willis, why didn’t you include Sofular cave data (Fleitmann et al, also on the NOAA web page) in your analysis ? With your assumption, the d18O values of that record would indicate a warm glacial and a cold Holocene.. interesting.

speleo PhD student
May 28, 2010 2:33 am

Willis, I wish I could continue discussing in much more detail but I don’t have time. You raised good points, however at the end, you will refute your own very first assumption, if you go on investigating. First of all, your first calculation reveals a positive d18O-temp relation, but you seem to be ignoring your own assumption. Second, d18O-Temp relationship may be in both ways, this is true, but you cannot take the inverse relationship out of context and use it as you want. For instance, time scale matters. On the very long term (the time frame of your analysis), if there is a relationship between temp and d18O, it must be a positive one – that’s why Sofular cave record is the other way around. All the other data sets you include are either rainfall records, or have something special to interpret the opposite. Again: rainfall cannot be regarded going always hand in hand with temperature… this is, believe me, a very bad assumption. Please don’t be the Michael Mann of the skeptic community, he does similar things. About Spannagel: inverse temp-d18O relationship is NOT assumed for the longer record… It is just for a part of the Holocene. In fact, for another stalagmite record from the same cave, which spans longer times and includes glacial/interglacial shifts (as in your analysis), the interpretation is the opposite:
“Part of the stalagmite shows three prominent δ18O maxima which according to the age model represent the three interglacials”
http://www.uibk.ac.at/geologie/pdf/spoetl08a.pdf

Editor
May 28, 2010 2:35 am

Willis
All credit to you for producing this article. I can’t help wondering that if only Al Gore had invented the internet earlier, what the debate would have been like if young and inexperienced Dr Mann had put up his tree rings work for open discussion on a forum such as this.
To me his findings were always ‘work in progress’ that begged many questions and much debate. Instead it was fast tracked to glory.
tonyb

May 28, 2010 2:45 am


Writes Willis Eschenbach: “Not safe for you to post under your real name? What has science come to, when an man can’t freely express his scientific opinions?
Er, Willis…. Where the hell have you been for the past thirty years or so? speleo PhD student has every possible good and credible reason to fear for his professional life when posting honest opinion – whether he is in error or not – on a forum such as this one.
One of the great values of anonymity (or pseudonymity) is that it facilitates this kind of wrangle. A scientist who does not have to worry about “going on the record” is not only able to blue-sky stuff that is brutally suppressed by superiors and other lictors but must also make his arguments intrinsically lucid, logical, and supported.
The writer functioning under a pseudonym has no “clout.” What you see in his posts is what you get, and his credentials don’t matter.
Dunno about anybody else, but I think that’s a major good thing.
The ability to hang stuff out there without fear of any consequences other than getting your nose yanked is also a major good thing, no? For any speleo PhD student who is in the process of trying his professional muscles, participation under a false name in a venue like this one is golden.
What, you think he’s gonna get this kind of feedback – or opportunity to speak freely – among his careerist peers and preceptors?

BBk
May 28, 2010 5:38 am

” if there is a relationship between temp and d18O, it must be a positive one”
Why MUST it be positive, when other sources say that it can go either way depending on location? If you’re going to educate, lets get to the crux of the matter instead of simply stating something as fact, shall we?

speleo PhD student
May 28, 2010 6:45 am

@BBk: Why do you take my words out of their context? I said:
“ON THE VERY LONG TERM (the time frame of your analysis), if there is a relationship between temp and d18O, it must be a positive one – that’s why Sofular cave record is the other way around.”
This is so, because the temperature difference between glacial/interglacial is so high that the first-order temp-d18O relationship (temp+ -> d18O+, which Willis derived correctly at the very beginning, but strangely utilized in the opposite way) dominates, unless your record comes from an area where the d18O-precip amount relationship (precip + -> d18 -) dominates even the first-order temp effect. The inverse relationship is, on the long term, not with temp but with precip.
I did not say “if there is a relationship between temp and d18O, it must be a positive one”, alone.
@Rich Materese: Thanks for understanding my concerns. You are spot on.

Ryan
May 28, 2010 7:27 am

Willis, apologies for my earlier remark. I clearly didn’t have my brain engaged when I didn’t spot the difference in horizontal scales used!
I think it is key here to understand if this proxy is “bang-up-to-date” i.e. the last data is indicative of the state of present day temps rather than 1000 yrs ago. The ice-core data is not so0 up to date, because ice-cores take time to freeze in the record of the temp proxies.
However, I notice with interest that the orange dots appear to have the same pattern as the purple dots but displaced by about 1500 yrs. Could that be because they are caves in different hemispheres? – there was a comment earlier in this thread that climate patterns in the northern hemisphere follow the southern hemisphere by 1500yrs, according to the ice-core record. or maybe the cave is just deeper?
As I said before, the thing that interests me more is the fact that we seem to be about 1/3rd of the way through a linear decline from the peak temperatures immediately after the end of the last ice-age to the worst part of the next ice-age. This is what the ice-cores say should be happening, in which case the CO2 clearly isn’t doing nearly enough to stop the next ice-age happening!

May 28, 2010 8:32 am

Is there any correlation with the Milankovitch cycles?

William Roberts
May 28, 2010 8:37 am

Just to chime in some more logic to this incoherent post. Thanks phd student for trying to bring truth to this mess.
Independent evidence: marine sediment cores from the tropics measure an upper limit of 3 degrees C cooling for the tropics during the LGM compared to present. So why are stalagmites from Indonesia, Borneo, Panama, Oman etc showing more than a 10 degree C temperature change according to the “I’m just playing around” excel graph?
Because they are records of hydrologic changes. NOT temperature. This post is randomly using a transfer function based on thermodynamic equation of fractionation in the formation of calcium carbonate, which yields bogus conclusions in these records. Obvious ploy. NOT science. No clap-clap, backslap from me for this post.

William Roberts
May 28, 2010 12:41 pm

nice duck and dodge. here are two nice compilations of SST measurements from marine sediment cores. I’m surprised you didn’t know of them, being a mariner and all.
Leduc, G., R. Schneider, J. H. Kim and G. Lohmann (2010). “Holocene and Eemian sea surface temperature trends as revealed by alkenone and Mg/Ca paleothermometry.” Quaternary Science Reviews 29(7-8): 989-1004.
Waelbroeck, C., et al. (2009). “Constraints on the magnitude and patterns of ocean cooling at the Last Glacial Maximum.” Nature Geoscience 2(2): 127-132.
These are reviews of a whole lot of paleo SST reconstructions. NONE of them have a 10 degree cooling of the tropics during the LGM.
Did you not know about this entire branch of paleoclimate research???
So I say, AGAIN, that the tropical speleothem records you have plotted above (in whatever program you want to use) are NOT simply records of temperature. They are records of changes in hydrology. I’ll be glad to lose bonus points on incorrectly guessing the program you used as long as I get an “A” on the science. …you get an “F” on the science. Unfortunately, your bonus points don’t help you to pass.

BBk
May 28, 2010 4:31 pm

“This is so, because the temperature difference between glacial/interglacial is so high that the first-order temp-d18O relationship (temp+ -> d18O+, which Willis derived correctly at the very beginning, but strangely utilized in the opposite way) dominates, unless your record comes from an area where the d18O-precip amount relationship (precip + -> d18 -) dominates even the first-order temp effect. The inverse relationship is, on the long term, not with temp but with precip. ”
While that may be so, I still don’t see any rationalization for the idea that that the slope can not remain negative indefinitely. Is it physically impossible to find microclimates that would behave in such a way for a long time period? All you seem to have said is, “it depends on your area which of the terms contribute most greatly.” and yet you seem to be implying that Willis’s chart should be flipped upside down, with the ice age being the hottest temperature on record?
For the record, I’m largely uncomfortable deriving hard numbers from ANY sort of proxy data, because the scientist brings too many assumptions to the table to be anything other than a “decent approximation.” So, a proxy may show a trend, and a shape, maybe… but I rail against anyone trying to use things like this as proof of much of anything that requires any accuracy/precision because the numbers are neither accurate nor precise as you note… if the slope can be positive, negative, and anything in between, then no good independant numerical data can be derived. All you can do is try to guess based on fitting data to other data. Of course, that means that your new data is really no better than the old data.
As a shape, Willis’ curve seems largley consistant with other sources. None of the curves can be declared very authoritative in terms of magnitudes as far as I can tell though.

phlogiston
May 28, 2010 7:21 pm

William Roberts says:
May 28, 2010 at 8:37 am
Just to chime in some more logic to this incoherent post. Thanks phd student for trying to bring truth to this mess.
With characteristic narcissistic arrogance AGW drones are trying to bring mess to the truth.
What is remarkable looking at the data as a whole is that speleothem records from every corner of the globe give a coherent record which is consistent with ice core and other reconstructions of terrestrial temperatures. This of course undermines one of the AGW “we’ve got to lose the MWP” strategies of trying to argue that any climate temperature change recorded in a palaeo reconstruction must be only local and not global, unless it involves CO2 emitted by enemies of the people.
The disorganised barrage of factoids presented by assorted trolls and PhD students include the idea that the relationship between d18O and temperature is variable and dependent on location. If so, why the coherence in the data? If this were true then the data would indeed be a mess and show no trend. But they’re not.
The left-field introduction of SST reconstruction by William Roberts is indeed irrelevant and bizarre. Obviously an attempt to confuse and muddy the waters. Obfusticating further, we are told “tropical speleothem records … are NOT simply records of temperature. They are records of changes in hydrology.”
O how interesting! According to CAGW, the weak effect of CO2 in increasing atmospheric temperature is amplified by positive feedback from the hydrological cycle, clouds and precipitation – which one would assume implies a correlation between temperature and the hydrological cycle. But here, for the sake of rubbishing speleothems as a temperature proxy we need to imply no correlation between temperatures and hydrology.
This is of course all diagnostic of AGW professional training – any signs of being able to hold more than one idea in your head at once and it is “go directly to the job centre, do not pass go, do not collect 200”.

dp
May 28, 2010 11:28 pm

On your next outing you might try searching for cockles and gastropods – they tell quite a story:
http://www.sciencedaily.com/releases/2009/10/091027170853.htm
Bob Dylan was wrong – the answer isn’t blowing in the wind, it’s buried under our feet.

Ulric Lyons
May 29, 2010 4:34 am

The Older and Younger Dryas, and the coldest event cluster since then, the LIA, can all be mapped out astronomically with ease and precision. The larger period to be concerned with at this level is the period between Heinrich events. This is a product of the all important angular relationship between Earth/Venus, and the four big Jovians. They return to produce the most similar condition, every 4627.33yrs. Three of these periods are between the Older Dryas and the LIA, so three steps on from the Youger Dryas leads to a return cold cluster, starting around AD2450. The period between the two Dryas events is half of the Heinrich event period. One quarter of the 4627.33yr period maps the RWP, MWP, modern warming events, and the LIA, Dark Ages, Greek/Homer cold periods.
I do not think that the general slow fall since the Holocene Optimum (Bronze Age) will fully mitigate the return of some very warm periods over the next 300/400yrs.
On the longer scale, the older 41,000yr (40979) ice age sequence still shows in the last c.100kyr cycle;
http://3.bp.blogspot.com/_cHhMa7ARDDg/SmDoZBIkB3I/AAAAAAAABAc/KkUzrz2abwI/s1600-h/Vostok-140Kc.jpg
20,000yrs to the next super cold episode.

Ulric Lyons
May 29, 2010 4:37 am

Correction
so three steps on from the Youger Dryas leads to a return cold cluster, starting around AD3600AD.

Davesix
May 29, 2010 11:33 am

Willis, I see that Matt Ridley used your graph and gave you credit in a post at Rational Optimist:
http://bit.ly/ctFoa0

phlogiston
May 29, 2010 11:25 pm

Caves are an integrator of temperature, Willis informs us. Are they not also an integrator of rainfall (precipitation)? Ground water tables only change level slowly in response to several years with increased or decreased rain. So for precipitation / hydrology not to confound speleothems as a temperature proxy, hydrology would have to correlate with temperature averaged over several years, not on a year by year basis.
The representation of the current interglacial including the Younger Dryas by Dr Eschenbach’s speleothem temperature reconstruction, including the highly plausible central peak and overall symmetry, seem compelling. This could emerge as a very important temperature proxy. The dip before the interglacial is curious (13-14 ky ago) – has this been seen before?

May 30, 2010 12:54 am


Having myself no dog in this fight (PETA be damned), I comment here only to observe that these exchanges represent what I conceive to be one of the best uses of such fora in the advancement of scientific inquiry.
This is something akin to an extended wrangle among graduate students and post-doctoral fellows without the suppressive intrusions of the professoriate – or a wrestling match among resident physicians and subspecialty fellows without a preceptor attending physician’s nose stuck into the give-and-take.
Reminds me of time-wasting sessions down in the bowels of Medical Records when we were supposed to be dictating discharge summaries and instead sought salvation from agonizing boredom in disputation on specific cases and on clinical medicine in general, with the added benefit conferred by present participants’ abilities to open a browser tab or window on the side and search the literature for supporting information and citations.
This is damned healthy, and I’d be interested to learn to what extent something substantive gets into the published literature as a direct or indirect result.

Ulric Lyons
May 30, 2010 3:39 am

@phlogiston says:
May 29, 2010 at 11:25 pm
“Caves are an integrator of temperature, Willis informs us. Are they not also an integrator of rainfall (precipitation)? Ground water tables only change level slowly in response to several years with increased or decreased rain.”
Good point. Cave temeperatures vary less than open air changes, and in some caves, can be very stable.

May 30, 2010 5:25 am

phlogiston says
“The dip before the interglacial is curious (13-14 ky ago) – has this been seen before?”
I am also puzzled about that, I would also like to find to know the answer to that question? It seems not quite to fit in with the greenland ice core data.
http://wattsupwiththat.com/2009/12/09/hockey-stick-observed-in-noaa-ice-core-data

May 30, 2010 5:34 am

henry@phlogiston
Sorry about that, it seems the 6th graph of
http://wattsupwiththat.com/2009/12/09/hockey-stick-observed-in-noaa-ice-core-data
does seem to confirm to me that temperatures did go down a bit @ 12-13 kyr BC

May 30, 2010 12:17 pm

HENRY@Willis
I must say that the data towards the end (the current warm period) do have a wide spread, ranging from -6 to +5 . Do you know why is that? I am puzzled that the average here does not show the 0.7 degrees or so increase of the last 150 years. So, what are we saying? If you look inside the caves, there really was no global warming (outside) ? Or was it just too little to notice? Or is the 0.7 perhaps wrong?

May 30, 2010 12:19 pm

Henry@Willis
Oh yes, it was also not clear to me until what year the data go.

William Roberts
June 1, 2010 11:52 am

The northern hemisphere speleothem records look like temperature records because the earth was deglaciating (IOW, the ice caps were melting). That is sure to cause a worldwide response – in temperature and in the hydrologic cycle. However, the nature of this change is not simply “warmer, wetter” all over the planet. There is actually a hemispheric “see-saw” of more rain the southern hemisphere when it was colder and less in the northern.
here’s a good ref:
Wang, X., et al. (2006). “Interhemispheric anti-phasing of rainfall during the last glacial period.” Quaternary Science Reviews 25(23-24): 3391-3403.
That is a speleothem record from Brazil, by the way. …AND the authors interpret it as rainfall changes. Like many of the other authors you claim do not.
Also, global average cooling was ~6degC during the LGM. ~12C at the poles. ~3C in the tropics. …so your guesstimation of only being 25-30% too large is… well… wrong. You are about 180% off. 8.5degC vs. 3degC.
Too call this investigation preliminary is a bit premature. It needs quite a bit of work before you could categorise it as a preliminary investigation.
Also, you say:
“Tropical SSTs vary much less than land temperatures, and are only a tiny part of the hydrological cycle.”
Uhhhhh, so ocean SST changes minimally affect the hydrologic cycle? I guess El Nino is a myth, eh? …El Nino causes tiny changes in rainfall. ….rriiiiiiiiiiggggghht.
I eagerly await your dodges.

phlogiston
June 1, 2010 2:56 pm

William Roberts
How bizzare would it be if global temperature correlated with glaciation and ice extent?! O thank you for correcting such a foolish error!
Odd how such a fuss is being made of Arctic extent and glacier retreat / advance, when they are unrelated to climate temperature. At least now we know that ice is not affected by cold or heat.
What a truly educational site this is!

William Roberts
June 3, 2010 12:02 pm

you say: “You appear to be saying that the speleothem records were precipitation records that also look like temperature records because … well, you don’t say why.”
uhhh – reading comprehension. Yeah, that’s what to say here. I DID say why. The earth was deglaciation. Continental ice caps were melting. That little speed bump caused worldwide changes – including, but not limited to, temperature and precipitation.
Alternatively, over the course of the Holocene, insolation changes caused the see-saw pattern in hemispheric precipitation. And I DID give you a ref. You should’ve read it before you asked your question. So reading comprehension again. Read the Wang ref.
I’m focusing on the tropics b/c they are the biggest hole in your initial plot for this post. To say those records are temperature is a way off the mark.
Also, I think you should read a bit more about the effect of tropical sst’s on global climate. Where do you think most of the water in the atmosphere comes from? Hint: warm, tropical waters.
Since you want quotes of what you said, here’s one “Yes, El Niño has a large effect … but that’s only a small part of the tropical SSTs.”
No. El Nino is directly related to/a manifestation of changes in tropical SST. And the changes in tropical SSTs/El Nino are substantial worldwide, not a “small part”. If you say “no” to that, then now you are just disagreeing with no scientific basis.
you say: “Most tropical SSTs don’t vary much. As an example, there has been no warming trend in tropical SSTs since the start of the satellite record (1979).”
wrong again. try here
Cravatte, S., et al. (2009). “Observed freshening and warming of the western Pacific Warm Pool.” Climate Dynamics 33(4): 565-589.
or here
Lyman, J. M., et al. (2010). “Robust warming of the global upper ocean.” Nature 465(7296): 334-337.
read the wang reference and then see if that addresses your 1,2,3 questions.
hopefully you will focus on the science and not trying to act like a martyr and correct me like you were my dad.

William Roberts
June 3, 2010 4:02 pm

sure sure. you’re right. golf ball bathroom. got it.
Now we can stop complaining about tone.
you say: “So you are saying that the record I showed is a precipitation record that also shows temperature? It’s very hard to try to dig out your meaning.”
Did you read the wang paper? That should clear up what I am saying.

William Roberts
June 4, 2010 6:48 am

uhhhh, yes it can. I don’t want to have to tell you the play-by-play of the whole paper when you can just read the paper yourself. Sorry, trying to be scientific and not lecture you about it. Let me know when you’ve actually read it so we can discuss the science more.
Oh, and about your in-depth analysis of the Lyman paper: so you’re judging a book by its cover (or title as it were) now? Good call. And given that each year in the paper consists of hundreds, if not thousands of data points from buoys and floats, your 16 degrees of freedom and resulting p-value mean squa-doosh. So the trend, which you confirm, is “robust”. …but of course you would’ve known that if you actually read the paper as opposed to conducting your rigorous scientific analysis without even reading it.

William Roberts
June 4, 2010 8:00 am

I posted a reply this morning. Will it show up later? Or are you censoring posts?
REPLY: Or maybe people have lives and we just finished getting the kids ready for school? – Anthony

William Roberts
June 4, 2010 8:01 am

nevermind. It just showed up. Weird. sorry for multiple posts.

William Roberts
June 7, 2010 9:08 am

First off – wow this post is already on page 3 of this blog. you guys really churn them out here. …I doubt anyone is actually even reading this thread anymore as it is already buried. So I guess it’s just you and me. Too bad b/c finally people may understand the mistakes you have made.
Second – nice double talk. Way to avoid addressing my comments by repeating the question.
third – yes, I DID in fact answer your questions. The change in precipitation from glacial times to present occurred b/c the earth warmed up. Warmer earth, more rain in many places. Over the course of the Holocene, there is a phase-shift of 180 degrees between the northern and southern hemispheres. That’s why the China speleothem and the brazilian speleothem records have opposite trends over the Holocene. As is VERY evident in the paper. And is what I said here:
“The earth was deglaciation. Continental ice caps were melting. That little speed bump caused worldwide changes – including, but not limited to, temperature and precipitation.
Alternatively, over the course of the Holocene, insolation changes caused the see-saw pattern in hemispheric precipitation. And I DID give you a ref. You should’ve read it before you asked your question. So reading comprehension again. Read the Wang ref.”
Therefore, you are incorrect again. We both said the same things. ..also, how many times do I have to say it???
Fourth – why would you see my name in the wang paper? I didn’t have anything to do with it. It is part of the answer to why your post is incorrect. That’s why I shared it with you. …now who is being uncivil???

William Roberts
June 9, 2010 1:41 pm

If I’m Gene Kelly, then you are Cyd Charisse.
What I’m saying is this: speleothems record a combination of temperature and precipitation changes. If you have a way of determining the change in temperature via other means, say a nearby marine sediment core – then you have an independent constraint on temperature. You can convert that temperature to d18O of calcite using a thermodynamic equation. The resultant change in calcite d18O cannot be due to temperature. It is due to amount or the source of precipitation.
clear enough??? probably not, so go ahead and fire away.
And I did comment on your analysis of the Lyman paper. I said you didn’t properly count the degrees of freedom for your p-value. reading comprehension.
As to who is uncivil??? Both of us are guilty. I can live with it. Can you???

William Roberts
June 14, 2010 10:17 am

SO- back to your original post where you put absurdly large temperature variations for cave records in the tropics and sub-tropics: do you plan on re-posting with an update? …Or just leave your readers with false information.
This post is already on page 4 of this blog, so you guys aren’t afraid to crank out a post.

William Roberts
June 16, 2010 7:35 am

Question regarding the p-value: if they calculated 6 month averages instead of annual using the thousand of data points and then you did your trend significance — would it be significant then???
How about 4 month averages (ie. seasonal)???

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