While trawling for high-resolution ocean sediment cores, I noticed an interesting core offshore Morocco, reported by McGregor et al (Science 2007) earlier this year. This study was released just prior to IPCC complete with press release. Can’t we all think back to a quieter time when a scientist having labored to produce a detailed analysis of ocean sediments or tree cores would merely publish his study in an academic journal? When I first became familiar with the climate field, I was astonished at the idea of scientists issuing press releases that would make mining promoters cringe. This study is an interesting example of the counterplay between the fine print of the academic article and the promotion in the newspaper.
The heading to this thread is from an article by the Australian Broadcasting Corp (ABC) that went on to say:
Global warming puts fish stocks at risk Their analysis found that climate-induced changes in the ocean have never been more dramatic than in the past three or so decades.
The core in question was from 30.845N 10.0983W in 1999 at 355 m depth. GeoB6008-1 was 5.4 m long, sampled at 2 cm intervals, with resolution decreasing downcore from 6 to 25 years; the top value dated to 1971, the bottom to 518 BC, GeoB6008-2 was a short core sampled at 1 cm intervals and dated from 1998 at the top to 1912 at the bottom, with resolution decreasing from 2 to 4 years.
Alkenone values were obtained for use in SST calculations (available here) . The raw alkenone values are shown in the graph below against depth, and,as you see, they show a remarkable change through the 20th century. On the right is shown the HadSST gridcell value for the relevant gridcell, showing an increase of about 1 deg C. This core (31N) is just to the north of the “Main Development Region” for hurricanes (up to 20N). The vertical dashed line marks the depth allocated to the start of the 20th century in GeoB-1.
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Left: Alkenone versus depth. The points show the short GeoB-2 core and the lines the long GeoB-1 core. The vertical dashed line marks the depth allocated to the start of the 20th century in GeoB-1. Right HadSST for gridcell 32.5N, 12.5 W containing the core location.
So this looks like evidence that Al Gore would love. Something unprecedented in the core. Fish stocks at stake. But there’s a catch (which Richard T may have spotted already.) The catch is nothing to do with bioturbation – although, as an aside, having seen similar sorts of changes through the mixed layer in connection with coarse fraction, I do wonder whether there might be some unconsidered interaction going on in the mixed layer that might account for this change. (But that’s not the issue today.)
Take one more look at the graph and see if you can figure out the sleight of hand that I’ve done here.
Here’s the trick. I’ve plotted the alkenone values upside down (relative to their use as temperature proxies.) The 20th century SST estimates based on alkenone show an unprecedented decrease in SST values so that there is a divergence of about 1.5 deg C between the alkenone SST values and HadSST values during the 20th century.
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And despite the headline from ABC that “Global warming puts fish stocks at risk”, the follow up paragraph in that article and a contemporary Daily Telegraph article both reported unprecedented cooling:
Dr Helen McGregor and her research team from MARUM Research Centre Ocean Margins at the University of Bremen in Germany report in the journal Science that climate-induced changes in the ocean have never been more dramatic than in the past three or so decades. Sea surface temperatures in this part of the Atlantic Ocean declined by 1.2’C during the 20th century, say the researchers.
The seeming conundrum was explained as follows:
“The stronger the greenhouse effect the stronger the cold water pump works – and the cooler the coastal waters off Morocco,” says McGregor.
The Daily Telegraph article mentions that these upwelling systems are excellent for fishermen.
Upwelling systems like that off northwestern Africa are of great economic importance. Although they cover less than one per cent of the global sea surface, about 20% of global fishing takes place there and they are potentially important for drawing down carbon dioxide from the atmosphere.
However the scientists were able to find a cloud in the silver lining. McGregor warned that the fish might have trouble swimming in the nutrient-rich upwelling system:
While an increase in nutrients has the potential to increase fish stocks, the strength of the offshore currents may be too strong for fish to swim against, says McGregor.
I had innocently thought that fish were nicely adapted to the water. Will swimming lessons for fish be part of IPCC mitigation strategy? Inquiring minds want to know. McGregor also warned darkly of further bad consequences if fish were unable to swim in the nutrient-rich waters:
“Our research suggests that upwelling will intensify with future greenhouse warming, however it is unclear whether fish will be able to counter the stronger upwelling currents and benefit from the likely increase in phytoplankton (phytoplankton increase due to higher nutrient levels),” said Dr McGregor.
If phytoplankton populations are left unchecked then the higher deposition of organic matter on the sea floor could lead to the build-up of toxic hydrogen sulphide gas (rotten-egg gas), poisoning marine life and further degrading marine ecosystems.”
The news report ended by saying:
The new study is released just hours before the official release of a major IPCC update about global warming due to be unveiled in Paris this evening.
The Divergence Problem
The authors discuss the “Divergence problem” in their supplementary material as follows:
Note on instrumental versus alkenone SSTs: Direct comparison of the alkenone SSTs with instrumental SSTs is problematic, as ships-of-opportunity pass too far from the Cape Ghir coast to measure SST in the upwelling area (S35, S36). A compilation of sporadic SST measurements between 1947 and 1979AD collected by different research vessels operating in the Cape Ghir region, gave an estimated mean annual SST of 17.1’C (S37). In contrast, Hadley Centre SSTs (HadISST_1.1_SST -blended ship and, when available, satellite data (S38)), averaged over the 1’x1” grid square that includes site GeoB6008, and for the same period, gives an annual SST of 19.9’C. The absolute UK’37 SST for the uppermost sample for GeoB6008-1 and GeoB6008-2 are 18.7’C (1971AD) and 17.7’C (1998AD), respectively.
S35. W. S. Wooster, A. Bakun, D. R. McLain, Journal of Marine Research (1976).; S36. L. Nykj’r, L. Van Camp, Journal of Geophysical Research 99, 14197 (1994).S37. E. Hagen, C. Z’licke, R. Feistel, Oceanologica Acta 19, 577 (1996).
Also: this SST series with its sharp 20th century decline is sufficiently resolved to meet inclusion standards for multiproxy studies. Using Loehle’s methods, the series would be averaged. Under more “advanced” methods, the series would be flipped over and the increased cold interpreted as evidence of global warming, as ended up happening in Moberg and Juckes.
Reference:
McGregor, Helen V; Dima, M; Fischer, Helmut W; Mulitza, Stefan (2007): Rapid 20th century increase in coastal upwelling off northwest Africa, Science, 315, 637-639, doi:10.1126/science.1134839. Also see PAGES newsletter here
Climate Audit 
73 Comments
Ah, hey. Come on. You know what kind of science this is.
This is possible, but don’t these Rube Goldberg theories seem a bit convoluted and contrived?
They say the Hadley SST grid is too big and doesn’t record the upwelling zone they are sensitive to…
check out the SOM:
Note on instrumental versus alkenone SSTs
Direct comparison of the alkenone SSTs with instrumental SSTs is problematic, as
ships-of-opportunity pass too far from the Cape Ghir coast to measure SST in the upwelling
area (S35, S36). A compilation of sporadic SST measurements between 1947 and 1979AD
collected by different research vessels operating in the Cape Ghir region, gave an estimated
mean annual SST of 17.1°C (S37). In contrast, Hadley Centre SSTs (HadISST_1.1_SST –
blended ship and, when available, satellite data (S38)), averaged over the 1°x1° grid square
that includes site GeoB6008, and for the same period, gives an annual SST of 19.9°C. The
absolute UK37 SST for the uppermost sample for GeoB6008-1 and GeoB6008-2 are 18.7°C (1971AD)
and 17.7°C (1998AD), respectively.
Interestingly in that core, the LIA was warmer and the MWP was colder…
Shouldn’t there be a peer reviewed journal with a title something like, “CLIMATE COMEDY”. With each passing day the silliness of so many climate papers is unbelievable. Equally unbelievable is that so many sites (Realclimate comes to mind) that will give these papers a status roughly the equivalent of the famous stone tablets of Moses.
And in this case, there’s a cornucopia of comedy to choose from. Not only is “cold” the new “hot,” but the poor fish have devolved into bad swimmers to boot. This global warming is powerful, powerful stuff.
If I squint really, really hard I can see a hockey stick with a really big blade in the upper left graph (in on the comment before sod makes it) …
/sarc
“swimming lessons for fish” 😀 That’d be a GREAT name for the CA newbie site.
I can’t keep up. Wasn’t GW supposed to cause the Greenland ice sheet to melt and slide off into the Atlantic, shutting down the thermohaline conveyor? Now, it’s supposed to speed the conveyor up so fast the fish can’t swim? What’s the official party line, here? Speed up, or stop?
I saw a headline the other day that was along the lines of, “Global warming puts strain on meat and vegetables.” I couldn’t get myself to read the article.
Re #9, Larry a real climate scientist would probably answer, “yes.”
Steve, it is difficult to avoid politics, or even to remain on topic with subjects such as this one.
“The fish swam with the current before they swam against it”.
220, 221, whatever it takes
The divergence is obviously a recent change in teleconnection. See, this CS is so easy.
The following reference does not qualify as a “climate paper” but could be considered as another example of the practically obigatory need to attach some speculation about AGW being associated with any negative natural event. Because it also reported several other speculations, the article was not biased in favor of warming being the cause of the problem. The Wall Street Journal, “Invasion of Jellyfish Envelops Japan In Ocean of Slime, Pink 450-Pound Blobs Clog Nets but Spur New Recipes; Pointing Fingers at China”, By SEBASTIAN MOFFETT, November 27, 2007; Page A1.
One of the possible causes listed for the invasion:
Partial solution to problem, (might be more useful than some proposed AGW solutions):
I find the science revealed in this thread intriguing and certainly worth the time to look into it further and in more detail. The object lesson I take away from this thread is something very different: The science can present contradictory stories, but the story taken away after some nonscientific hand-waving in concluding remarks and the press conferences that follow is that same old story that GW can only produce bad results and never good. If you think good, you simply have not looked at the issue from the correct perspective.
Here’s the sea temp anomaly chart:
I don’t see any cooling near NW Africa.
O…M…G…!
If “killer AGW” is allowed to continue, we’ll all starve! Therefore, let us slow it, stop it and eventually, reverse it. Sequester CO2, overtly cool the earth. That way, we shall have more food? Correct? That’s correct isn’t it? Anyone?
The 21 November 2007 attack by jellyfish on farmed salmon in Northern Ireland (killing 100,000 fish) is being attributed by some sources to global warming:
http://www.spiegel.de/international/europe/0,1518,519666,00.html
“Many scientists regard an unprecedented swarm of Mediterranean jellyfish in Northern Irish waters as a sign of global warming.”
http://www.cnn.com/2007/WORLD/europe/11/21/salmon.jellyfish.ap/index.html
“Until the past decade, the mauve stinger has rarely been spotted so far north in British or Irish waters, and scientists cite this as evidence of global warming.”
http://ap.google.com/article/ALeqM5hvpCeL6fPyQxurXJJEWrFiCCkd4QD8T281N02
“The species of jellyfish responsible, Pelagia nocticula popularly known as the mauve stinger is noted for its purplish night-time glow and its propensity for terrorizing bathers in the warmer Mediterranean Sea. Until the past decade, the mauve stinger has rarely been spotted so far north in British or Irish waters, and scientists cite this as evidence of global warming.”
What unmitigated BS.
Global warming, if it is occurring, preferentially warms the polar regions, and reduces the strength of the “cold water pump.” Exactly the opposite effect that McGregor describes.
Can’t these guys keep their doctrine straight?
#17. Those are anomalies. You should check out raw SST’s.
And WOW. This La Nina is turning into a monster.
Even I can figure this out. All the ice burgs breaking off from the arctic (due to AGW) are floating down and cooling the waters at the equator.
Since this is a fishy research I vote for trolling for money from the gummint… 🙂
Larry says on November 27th, 2007 at 6:19 pm, ca. # 2:
SOP in metamagical Climate Science, but poor old William of Ockham must be twirling in his urn.
I have emailed and reprimanded the Australian Broadcasting Corporation for the lead story.
It cannot all be bad. The Dead Sea now has enhanced circulation due to Global Warming and the fish that rise to the surface are cooked and well salted. Yum, Kipper.
Seriously, we all know there is a desperate need for reliable and ever-longer proxies, but in time we will need to call off the search because no stone has been left unturned.
I see that papers are appearing on Calcium to Magnesium ratios in shells as proxy for marine temperature.
In mineralogy, a certain mixture of calcium and carbonate is calcite or aragonite, and a mixture with a certain amount af magnesium as well is dolomite. You learn this is Geology 1. Later you learn that many factors can affect the Ca:Mg ratios and you get to spell penecontemporaneous dedolomitisation for a party trick.
When you study plant and animal nutrition, the situation becomes even more complex because there are other major soluble cations that enter the story. The blood electrolytes have to keep Ca, Mg, Na and K within fairly narrow ranges relative to each other, but you can also get participation of strontium and lithium and other periodic table relatives.
In preliminary reading about Ca:Mg ratios in shells as reported in another post on CA (and used by Craig Loehle), I’d be very, very wary. For this marine thermometer to work, you need to establish that sea temperatures next to the growing shells were close to the average SST that you are trying to deduce: that the temperatures that matter are not confined to a growing season; that the available forms of Ca and Mg for uptake are not limited nor competing with relatives like Sr and Ba; that the Ca and Mg are distributed at microscopic scale adjacent to each other in the shell; and that the resulting shells are stable enough to resist even very minor leaching post-formation. BTW, I one almost finished a thesis on Ca:Mg ratios in plant growth. I stopped because too little was known of the outstanding questions to be able to continue…. continue ….
The ABC uses mathematics too, The ABC science guru DR Karl counted the articles for AGW in nature and found more published articles for it than against it. And, hes the bright one!!
Jimmy at #3 has already found the answer to this conundrum. HADSST grid cells are 5°x5°, a much larger area than the upwelling cells. Therefore, temperature changes in the whole grid-cell are not representative of the upwelling area.
And the fish. Juvenile fish are not good swimmers; juvenile planktonic fish are carried by the current. If the current takes them out of suitable habitat before they are large enough to swim against it, survival and recruitment will be poor. I don’t know how likely this scenario is, but it is plausible, and there are ecological models being developed that could test it.
Re # 28 RichardT
Is the forecast so gloomy that a food mechanism that brings the Bounty of Nature to small fish is so perverse that Nature also keeps the small fish away from it? Does it mean that fish food produced in cold upwellings is more likely to die of old age than from being eaten? I don’t know, but strange things can happen. It would be good if your findings give an answer to your wonderings, one that you can share with us.
Well…it all smells very fishy, indeed!
Add to it, the smell of the phytoplankton struggling and dying in their multitudes for want of sufficient iron to sustain their metabolism, and the irony of zooplankton starving the waters of oxygen as they decay. Feed or don’t feed the plankton, and a journalist will memorialize the fishy demise.
#29
Suffer little fishes, for nature is a great equivocator. The currents that bring forth your food, will carrying you unto your doom. Pray not for bounteous times.
Click to access Survival.pdf
#9 Larry,
Recently on a blog I observed a mathematical expression for your query. This should clear all remaining cofusion regarding this and other inconsistencies in climate science:
AGW causes X
X can be anything
The past three or so decades….the top 3 to 6 inches of the core? Is sampling/dating really that accurate/precise in the top few inches of the surface?
Fish might have trouble swimming against the stronger upwelling????
I was not aware that fish generally swam straight down?
#32
The area has a high sedimentation rate (210cm per thousand years), and the top of the core is dates with Pb210. Pb210 has a half-life of 22 years, and so is useful for sediment up to about a century old, typically with an uncertainty of 10-20% of the age. The uncertainty is minimal in the most recent sediments. The chronological accuracy that Helen McGregor reports is realistic.
#33
Upwelling is driven by wind-driven lateral movements of water, which create a void the upwelling waters try to fill. It is these lateral currents that transport the fish eggs and young away from their feeding ground.
Kenneth, #16
The AGW crowd — as well as environmentalists generally — hold that life in nature depends on the maintenance of a delicate balance of factors, the upset of any of which can prove “disastrous”. Thus any change that is detected can be interpreted negatively. Of course, if this model of nature were true, I don’t see how life would have survived things like the ice ages or the warmings that seperate them.
In any event, evolution teaches us that life in nature is not static and balanced, but dynamic, competitive and constantly changing. If it were not, we would still be in the trees.
Richard T, if upwelling is such a problem for fish, why are upwelling areas more productive than non-upwelling areas? Is there any evidence that fish have not adapted nicely to upwelling areas?
#36
Upwelling zones are indeed among the most fertile areas of the ocean. But the relationship between upwelling intensity and ecosystem productivity is not necessarily linear.
Try Ware & Thompson 2005 Science 308: 1280-1284 for counter-intuitive findings from the US/Canada Pacific coastline.
Larry #9:
You are behind the times. The issue’s no longer “global warming” or “climate change”, but rather Global Climate Destabilization. The next item in the declension is just “Climate Destabilization”, as evidence of which any minor local anomaly will serve.
Very few fish allow their eggs to just float in the open ocean. They are usually attached to the bottom or to bottom structures.
Ditto for young fish, they stay close to the bottom, in and around structures.
Richard T
Why do we need an ecological model, can’t someone just go out there and actually observe whether the upwelling has a negative effect on fish stocks?
So far this is just a stab in the dark or a hypothesis to test, why don’t we observe what actually happens due to upwelling) before we draw any conclusions from it?
Dr. Slop. Uncle Toby says hello.
#39
ichthyoplankton. Why would 139,000 pages refer to something that wasn’t important.
#40
Ecological models are useful because many ecosystems are difficult to manipulate experimentally. They can help to understand what the key variables in the system are, and, when validated against observational data, can be used to make predictions. With predictions, ideally with confidence intervals, suitable management actions can be taken to minimise the effects of ecological change. Waiting to see what happens allows only retrospective actions.
I can’t figure out how deeply the tongue is planted in the cheek on this one.
RichardT:
Won’t the current take the plankton and the fish?
More generally, in response to Steve’s tic(?) question:
Too much food, results in obesity and a myriad of well documented and related health problems!! Plus too much food now means that they will have problems when there is too little food in the future. A government program is clearly needed.
Where is Bjorn Lomborg on this one?
#42. Richard T, the primary claim of your citation is a “bottom-up” linkage between plankton production and fish yield:
It doesn’t say anything about fish having problems swimming and seems to support that idea that increased upwelling will yield more plankton and more fish – regardless of swimming lessons.
Re: 17
Ok, this might be a bit off topic, but here goes. I have a gripe with the way they plot the anomoly maps. The abrubt transition from yellow to blue to differentiate hot/cold is IMO a bit misleading. Wouldn’t it make more sense to have a common neutral color for -.25 to +.25 with color transitions on either end? As it is, it is difficult to see the difference (at least visually) between the really hot and really cold areas. Has anyone else noticed this?
Steven Mosher #41: The good doctor responds in kind. He also, on reflection, admits his formulation of the cline to be rhetorically incomplete, the ultimo element being most effectively dubbed “macronascent climate destabilization”.
There’s an important scientific question. The knee-jerk reaction is to model. What’s wrong with this picture?
RE 46. Curly concurs. Have you seen shemp
I remembered this article from last year:
“Marine Life Stirs Ocean Enough To Affect Climate, Study Says”
link
Shemp went fishing. Somebody told him to catch while the fishing’s good, because it’s all going to be gone in a year. What a stooge.
#44
OK, not about swimiming ability, but the ecosystem response to upwelling. In this region, upwelling and primary productivity are negatively correlated – a counter-intuitive result. Perhaps this is a different topic, but the result is the same. From page 1282:
“… chl-a concentration at the spatial scale of the NPAFC regions [is] negatively correlated with the annual cumulative seaward Ekman transport. The negative sign of this correlation is counterintuitive (in that decreasing seaward Ekman transport is normally thought to produce reduced primary productivity) and indicates that factors other than wind-induced upwelling are important for plankton productivity. For example, from spring to fall in the southern NPAFC regions, upwelling is frequently punctuated by flow events (14), which cause the seaward transport of plankton from the narrow (10-km scale) shelf to the deep ocean. As a consequence, a substantial fraction of the primary production in the coastal region from Pt. Conception to 43-N becomes unavailable to the resident fish ecosystem.”
Richard T, you say (or attribute the study as saying):
As you note, this does not support McGregor’s worry that future fish populations may need swimming lessons.
On a macro basis, upwelling zones coincide with high productivity all over the world. This study doesn’t overturn this. That local features may affect nuances of productivity geography is not necessarily inconsistent with this – so what?
#31 Peter:
Actually, your expression is slightly off. More correctly stated, it is:
AGW causes X
X can be anything BAD
richardT
It would appear that this study indicates that plankton from the upwelling are transported away by “flow events” out into deeper waters. So it isn’t that the fish are unable to swim to stay in the nutrient rich water but that the nutrients get swept past them.
This seems unlikely. If the plankton are “flowing” past why wouldn’t the fish be able to feed on them?
When I think of plankton I can’t help but envision the megalomaniacal character “Sheldon J. Plankton” from Sponge Bob Square Pants.
Felicitations, malefactors! I am endeavoring to misappropriate the formulary for the preparation of affordable comestibles! WHO WILL JOIN ME?!?
All this arguing about whether increased upwelling will overwhelm a fishes ability to swim.
Has anyone actually measured what the speed of the upwelling was, and what it is now?
The few numbers I’ve seen show that upwelling is not a particularly fast phenomena. Going from 10 feet an hour to 12 feet an hour would be enough to cool a sizeable area, but I doubt the fish inside the upwelling would even notice.
RE: #45, cbone:
I commented on map intervals and color choices on Unthreaded #23 Post 626, 6 Nov 2007 @ 4:34 PM.
http://www.climateaudit.org/?p=2220
Steve McIntyre replied:
Steve: Anna, nice point. Can you ping this again in a few weeks if Ive not posted something on it.
So, there may be something in the works!
The question of the Greenland icecap sliding off is rendered rather moot by the fact that it is sitting in a bowl. In fact recently studying a sub ice contour map of Greenland, it was evident that the centre of the icecap is at or below sea level, while the mountains around the perimeter are some thousands of feet high. Some slide off that would be.
Can’t get the hang of the block quote, this should have been there
Larry says:
November 27th, 2007 at 7:24 pm
I cant keep up. Wasnt GW supposed to cause the Greenland ice sheet to melt and slide off into the Atlantic, shutting down the thermohaline conveyor? Now, its supposed to speed the conveyor up so fast the fish cant swim? Whats the official party line, here? Speed up, or stop?
Fish modelling
No doubt the models that were so successful in preserving cod stocks off the Atlantic coast of Canada could be tuned up to deal with this problem. They were so good they would almost certainly predict unprecedented warming whilst killing all the fish.
Pip pip
Paul
Re 37 & 44:
The recurring “Dead Zone” on the Oregon Coast is claimed to be the result of upwelling caused by (drum roll) Climate Change
http://www.oregonlive.com/science/oregonian/index.ssf?/base/science/1185933323144640.xml&coll=7
#30 richardT
The study says:
Oh! great! Another computer simulation of NOT the real world to get alarmed by!
That late 20th century decline is pretty dramatic, much greater than anything else in the last 2500 years. A real Hockeystick, although with the blade going down.
The paper concludes ocean currents are a negative climate feedback and rapidly accelerating by the look of it. A rapidly accelerating negative climate feedback would be good news and therefore has to be ignored.
Interesting, it would appear the coastal current off Morocco is the inverse mirror image of the Humbolt Current off Chile and Peru.
The Humbolt Current flows north towards the equator and it is the coriolis force of the Earth’s rotation that causes it to spin counter clockwise (viewing north). This draws the cooler water from the depths and stirs up the sediments which makes for good fishing. Every now and then the coastal waters get warm and the fish go away. The fishermen called this el Nino because it happens in the period leading up to Christmas.
What the fishermen didn’t know is that the Humbolt current had slowed down because the Equitorial Pacific Current had slowed down because of a change in air pressure measured as the ENSO (the big monsoon making low pressure region that normally lives over the Philipinnes and Indonesia went on vacation to Acapulco).
The coastal current off Morocco is part of the North Atlantic Gyre which spins clockwise (viewed from space). If the upwelling off Morocco has increased because the speed of the current has increased then this suggests that the rotation of the North Atlantic Gyre has increased.
The thing is, I thought the North Atlantic Gyre was ultimately driven by the thermohalene circulation… in fact the Gulf Stream makes up part of the western leg of the North Atlantic Gyre.
So I’m not getting it. Is the thermohalene circulation slowing down or not?
I sort of picture all these currents in my head as giant gears all meshed together in a global clock but I guess I have to take into account the elasticity of water and therefore the potential lags in cause and effect when it comes to currents.
I wonder if the cooler surface waters off Morocco have in any way contributed to fewer hurricanes in the Atlantic Basin over the last two years?
Climate science is such a great spectator sport.
#67. The driving of the “thermohaline circulation” seems to be a topic of considerable pointless controversy. I’m satisfied that Carl Wunsch’s view that the sinking of dense brine does not drive the circulation are irrefutable; the circulation is wind-driven.
Having said that, if we are seeing an increase in upwelling, (Withotu taking a position here on whether this is actually the case), then there has to be an offsetting amount of downwelling somewhere else. Ergo, the circulation would necessarily have increased.
#62. I am increasingly suspicious of the mixed layer in these ocean sediments. There is everyday observational evidence of coarse material building up at surface and mechanisms for increased concentration of a coarse fraction in the surface mixed layer – something that is transitional and will disappear as the present mixed layer is eventually fixed.
The demands for more up-to-date calibration are causing ocean sediment people to include mixed layers with fixed layers in their analyses. When one sees extreme trends in a mixed layer – even if it’s something superficially unrelated to a mixing process e.g. alkenones – one really wonders whether there might not be some mixing process that hasn’t been studied.
Upwellings of cold sea water in isolated locations of the oceans, as described in this thread, would appear to make a case for teleconnected proxies in temperature reconstructions providing it can be shown that the upwellings are relatively stationary over long periods of time, and additionally can be related to a remote regional or global average temperature with physical evidence and finally can be validly calibrated with that temperature over the period of instrumental temperature measurements.
Is that evidence available for the upwellings that are described in this thread?
I would like to obtain more background information on teleconnected temperature proxies as it would appear the lesson I was expecting to obtain from JEG is not going to happen, or at least any time soon. In view of a teleconnection from an upwelling being consistent with the local temperature, that type of teleconnection is much easier to understand than one where temperatures in a local proxy are teleconnected/correlated to a global or other regional temperature while not correlating with the local temperatures.
RE: upwelling, downwelling (closure) & teleconnections
Was thinking of commenting earlier on this topic. Glad it’s come up.
If A is forcibly teleconnected with B is forcibly teleconnected with C, then at some point the teleconnections have to have global reach and C will reconnect back with A; it is a global circulation, after all. Are climatologists making a logical error assuming there is a pacemaker at the source end of the teleconnection? What if the “pacemaker” itself is being forced by weak inputs from X,Y,Z? For example, the Cook et al paper, where US drought is teleconnected back to the eastern tropical Pacific. If that area is running warm, that heat came from somwhere. But what if it comes from many places? Where does the search for teleconnections end? (Think about that texas sharpshooter. When does he get to go to the barn to draw his a posteriori targets?) And what if the X,Y,Z sources are always changing over time? How robust are those teleconnective correlations? Seems critical to me if you want to forecast the way Mann is.
Re: Ken’s quest for JEG’s lecture: I think the statistics of a global hunt for correlative telecennections is fraught with overfitting hazard (texas sharpshooter problem). JEG can probably explain the principle of teleconnection. I don’t think he can justify these correlations as anything but descriptive and highly optimistic.
Ken, I think the paradox you want resolved is explained by causation being a high-frequency phenomenon and teleconnective correlation being a low-frequency phenomenon. As long as the proxy models are mis-sepcified (e.g. conflating drought with temperature/growing season length), the low-frequency correlation at a distance might be higher than the local high-frequency correlation. The teleconnective hypothesis is nevertheless valuable because, given noisy data, the high correlation with the teleconnected pacemaker might prevent you from falsely concluding there is NO relationship between the proxy and its environment, when there may be a weak one. That doesn’t mean the teleconnective correlation is a correct description of the local response; it just means you need better data and a better model to obtain the correct response. If you did that you would see a higher correlation locally than abroad. Paradox resolved.
RE 67. Bender, I always thought the teleconnection arguments were proxys for “the dog ate my homework
sorry I coulnt sample the whole globe” that made some partial credit sense… But when I hear
you crtique it I’m thinking that I am missing something
Re: #67
Bender, I agree that your explanation (excerpted in part above) is the only one that makes sense vis a vis a correlation with a remote temperature and not the local one, but I wanted JEG to do the explaining and give some details that explain the a priors. I have a major problem attempting to determine how much some of these climate scientists appreciate the dangers of data snooping. JEG and Rob Wilson come to mind. Upwelling teleconnections being, I would think, much more amenable to straight forward a prior explanation than the no-correlation-to-local-temperature teleconnections, would provide considerably less opportunity for data snooping. In either case one needs to provide evidence for a reasonable physical connection that can be calibrated, validated, and give expectations of being more or less permanent over the time period of the reconstruction.
I think that to which Steven Mosher is referring in his posts here is that on face value it appears that temperature reconstructionists look to correlate with local temperatures, but failing that, take a shot at correlating with a global or a teleconnected regionally remote temperature without a sound connecting principle given. I would like to see more time spent on the connecting principles.
I have witnessed some lengthy debates at stock investing web sites where it was my judgment that some of the more intelligent participants were the most difficult to convince of the dangers of data snooping because it appeared they were convinced they could outsmart the market and thus their investing models, no matter how much they lacked out-of-sample testing and exhibited over fitting, had to be merely confirming what they already had surmised as being true.
#69 Ken, yes, teleconnection detection and inference uses the “snoopmax” algorithm. 🙂
But I agree, I too would like to hear it described by the people who do it, rather than myself. Becasue snoopmax is a BIG problem.
#68 mosh, the trick is this: causality and correlation degrade over space at different rates for different reasons. Causality is always stronger locally than at a distance. Everyone knows that. Correlation, however, is a sample statistic – a statistic that is prone to error from many sources. So sometimes it is higher further away than closer. Correlation does not equate with causation; it merely samples it.
“Teleconnection” is a sensible term in climatology, where there is no causal inference in the way to bugger up its meaning; Pacific air masses are teleconnected with California weather. In paleoclimatology, however, you have the cause-and-effect response of the proxy entering into the equation. In my view paleclimatologists are just being too cute when they use the term. I am glad that Ed Cook sees fit to put quote marks around it when he uses it in his papers. Why does he do that? I don’t know. Maybe he thinks it’s being a little too cute, or maybe worse, misleading.
I would like to see less time spent on teleconnection altogether. If you’re trying to measure the “global average”, then what good does it do if your tree located here is measuring the temperature of somewhere else? Now you’re weighting that somewhere else twice, and ignoring the fact that the tree here may be in a cooler climate, which would otherwise bring the average down. Teleconnection makes sense (in a perverted unproven sort of way), alarmist “climate scientist” applications of the concept make nonsense.
Mark
Hi, I just I’d add my 2 pence into this discussion…
it relates to the comment about increased upwelling which in turn would increase productivity..here goes…
It is the case with phytoplankton, and certainly has been seen in upwelling zones off the Iberian coast just a few degrees north…but with fish stock its been found to have a less than desired effect.
Santos et al. work on larval incubation in surface waters of the Portuguese coast revealed that the little blighters survival is dependent on more stable waters. Under upwelling conditions they simply get flushed offshore which doesn’t fair well for development nor recruitment
There’s a quick summary in the following link:
Click to access NL_54.pdf
I worked on marine fish species for a while in my life. Many are threatened by human action generally not climate change but most often by over harvest. Marine species, like insects, have evolved one critical survival technique, resiliency. They have been around a long time and have had to be able to survive through regular changes in ‘ocean climate’, e.g., Pacific Decadal Oscillation, ENSO, NAO, etc. It has been documented if we remove a large number of one species by harvest then other marine species take advantage of the opening niche.
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[…] One reason why Jansen took care to distinguish upwelling zones is that upwelling zones in the 20th century appear to go opposite to the general trend of increasing SST. For example, an upwelling zone off Morocco has had exceptionally cold alkenone SST results in high-resolution data covering the 20th century -see CA discussion of Cape Ghir data here. […]
[…] on a very high-resolution alkenone series offshore Morocco (about 30N) by Helen McGregor (see here and here). This dataset had a serious divergence problem, i.e. the water was getting colder. […]