![436189main_atlantic20100325a-full[1]](https://wattsupwiththat.files.wordpress.com/2015/03/436189main_atlantic20100325a-full1.jpg?quality=83)
The findings are the result of a new monitoring technique, developed by oceanographer Josh Willis of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., using measurements from ocean-observing satellites and profiling floats. The findings are reported in the March 25 issue of Geophysical Research Letters.
The Atlantic overturning circulation is a system of currents, including the Gulf Stream, that bring warm surface waters from the tropics northward into the North Atlantic. There, in the seas surrounding Greenland, the water cools, sinks to great depths and changes direction. What was once warm surface water heading north turns into cold deep water going south. This overturning is one part of the vast conveyor belt of ocean currents that move heat around the globe.
Without the heat carried by this circulation system, the climate around the North Atlantic — in Europe, North America and North Africa — would likely be much colder. Scientists hypothesize that rapid cooling 12,000 years ago at the end of the last ice age was triggered when freshwater from melting glaciers altered the ocean’s salinity and slowed the overturning rate. That reduced the amount of heat carried northward as a result.
Until recently, the only direct measurements of the circulation’s strength have been from ship-based surveys and a set of moorings anchored to the ocean floor in the mid-latitudes. Willis’ new technique is based on data from NASA satellite altimeters, which measure changes in the height of the sea surface, as well as data from Argo profiling floats. The international Argo array, supported in part by the National Oceanic and Atmospheric Administration, includes approximately 3,000 robotic floats that measure temperature, salinity and velocity across the world’s ocean.
With this new technique, Willis was able to calculate changes in the northward-flowing part of the circulation at about 41 degrees latitude, roughly between New York and northern Portugal. Combining satellite and float measurements, he found no change in the strength of the circulation overturning from 2002 to 2009. Looking further back with satellite altimeter data alone before the float data were available, Willis found evidence that the circulation had sped up about 20 percent from 1993 to 2009. This is the longest direct record of variability in the Atlantic overturning to date and the only one at high latitudes.
The latest climate models predict the overturning circulation will slow down as greenhouse gases warm the planet and melting ice adds freshwater to the ocean. “Warm, freshwater is lighter and sinks less readily than cold, salty water,” Willis explained.
For now, however, there are no signs of a slowdown in the circulation. “The changes we’re seeing in overturning strength are probably part of a natural cycle,” said Willis. “The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling.”
If or when the overturning circulation slows, the results are unlikely to be dramatic. “No one is predicting another ice age as a result of changes in the Atlantic overturning,” said Willis. “Even if the overturning was the Godzilla of climate 12,000 years ago, the climate was much colder then. Models of today’s warmer conditions suggest that a slowdown would have a much smaller impact now.
“But the Atlantic overturning circulation is still an important player in today’s climate,” Willis added. “Some have suggested cyclic changes in the overturning may be warming and cooling the whole North Atlantic over the course of several decades and affecting rainfall patterns across the United States and Africa, and even the number of hurricanes in the Atlantic.”
With their ability to observe the Atlantic overturning at high latitudes, Willis said, satellite altimeters and the Argo array are an important complement to the mooring and ship-based measurements currently being used to monitor the overturning at lower latitudes. “Nobody imagined that this large-scale circulation could be captured by these global observing systems,” said Willis. “Their amazing precision allows us to detect subtle changes in the ocean that could have big impacts on climate.”
Source: http://www.nasa.gov/topics/earth/features/atlantic20100325.html
h/t to WUWT reader Scott Gates
UPDATE: This story sent to me today was dated 3/25 and I originally thought it was new today. It was coincidentally 3/25 of 2010, not 2015. The first paragraph of the story has been changed to reflect this within 5 minutes of posting. h/t to Andrew Freedman – Anthony
Are we that stupid that one paper says one thing…and another the total opposite?
……..yes
Seriously, that’s par for the course for alarmists.
An easy way to catch any of them out (especially when they throw the “D” word at you) is to show them two contradictory alarmist papers (or just claims) and ask which one is true. They’ll either run away or claim that they’re both true (since CAGW is unfalsifiable*) and tell you that you don’t understand.
In either case, there’s no point talking to them any more.
*Actually, just asking them what conditions would falsify the theory (or just be able tell us when we’re all “safe”) would have them scurrying under the floorboards, too.
Mann gets a lot of press, and many people are starting to understand that he slants everything in order to “alarm.” It is his shtick, and it has made him famous (and slowly infamous).
I spent much time looking into the claims of Rahmstorf and came to the conclusion long ago that he is an “alarmist.” There is no better word for it – he does everything he can to wring out the greatest dread from his data.
See, for example…
https://climatesanity.wordpress.com/2012/09/29/rahmstorf-2011-robust-or-just-busted-part-5-why-a-paper-about-robustness/
I hope the world is catching on.
What nobody seems to comprehend adequately is that the “overturning” component of the AMOC is orders of magnitude weaker in heat transport and slower in speed than the purely advective component, amply manifest in the wind-driven Gulf Stream. It’s a miniscule side-dish in the movable thermal feast.
ftp://ftp.ncdc.noaa.gov/pub/data/paleo/climate_forcing/solar_variability/bard_irradiance.txt
Brandon, this is what you had sent yesterday. I have a few question on the interpolation of the data I would like to ask.
I do not understand the date -900,-901 etc and omega 27.86 for example. Thanks
I think it misconduct to not have referenced very available papers on the subject and dealt with their conclusions if one has confidence that their paper is more credible. I guess if that someone is one who has similarly examined and discarded all trees from a data base except those that support your meme, it is not surprising to see selective exclusion of directly contradictory work. This guy is finished and the next CAGW zealot for the psychiatrist’s couch.
ftp://ftp.ncdc.noaa.gov/pub/data/paleo/climate_forcing/orbital_variations/berger_insolation/bein10.dat
Brandon I meant the data from this one. Thanks.
Let me try this. In Berger’s normal terminology the parameters mean this: Omega is solar longitude measured with respect to vernal equinox on the date pertaining to the listing The numbers, -901, for instance are years prior to 1950. The orbital parameters are based on epoch 1950. so 27.86 is a day in mid-late April of year 1049CE. Note that the listings year by year, with extremely different values of omega, do not pertain to the same day of year. I do not understand the reason for structuring the data this way. Maybe Brandon has some insight into this.
Kevin Kilty,
Close to my understanding, but with one critical exception. The years are in thousands before/after 1950, so -901 would be -901 * 1,000 + 1,950 = -899,050, or 899050 BCE. Omega in those files may now make more sense to you.
Salvatore Del Prete,
For the Holocene to 1950, the bien1.dat is sufficient as it covers the 100 kyrs prior to and including 1950. bien11.dat covers 1950 through 100 kyrs into the future. I have a master spreadsheet with a bunch of this sort of data in it, interpolated annually which you are free to use (without warranty to accuracy, of course):
https://drive.google.com/file/d/0B1C2T0pQeiaSY0hST1pvS2RhSnM
Negative years are BCE, positive are CE. There is a year zero, which you should interpret as 1 BCE if you find it matters. Other notes:
ecc, omega, obl, prec, Ins_60N_Jun, Ins_70N_Jun, Ins_65N_Jun, Ins_50N_Jun, Ins_80N_Jun, Ins_90N_Jun are all from the Berger files listed above. All insolation figures converted to W/m^2. Ins_65N_Jun is “interpolated” as the arithmetic mean of 70N and 60N.
TSI from -7360 to 1610:
Steinhilber, F., et al. 2009.Holocene Total Solar Irradiance Reconstruction.
IGBP PAGES/World Data Center for Paleoclimatology
Data Contribution Series # 2009-133.
NOAA/NCDC Paleoclimatology Program, Boulder CO, USA.
TSI from 1610 to 2008
ANNUAL MEAN TSI: Lean (GRL 2000) with Wang Lean Sheeley (ApJ 2005) backgroundMon Apr 6 11:29:27 2009 PMOD absolute scale - multiply by 0.9965 for TIM scale
TSI [W/m2] Total Solar Irradiance
CO2 and CH4 are composites from several sources, the paleo data from Epica Dome C, Taylor Dome and Vostok. The values for each are ln(CO2/280) and sqrt(CH4) – sqrt(680). The interpolations for the gasses are linear. All other series, including TSI, used a cubic spline interpolation.
PS — the linked file is tab-delimited .txt.
Now I know you’re not a climate scientist.
You corrected yourself instead of the date(a)!
LOL!
I know that NASA’s ocean circulation map is a simplification, but that North Atlantic loop is backwards.
You are correct. The main warm northerly is the Gulf Stream, which starts with a loop through the Carribean, exiting through the Florida Straight then up hugging the Fl coast. Where I am, about 7 miles offshore and visible some days. RAPID shows that also. But AW chose an illustration acompanying the NASA paper PR featured in the post. You can check that on Google images. Good enough for government work!
I thought that too , but did not have the courage to mention it.
I took it that this diagram is very much a generalisation, i.e. that the warm water goes N on the surface of the N Atlantic and S at depth. I would think that those who know about these things would know that the Gulf Stream runs N of Cuba and up the E coast of N America and as the N Atlantic Drift goes across to the N of Norway, but that the general effect is that warm water goes N on the surface.
The whole point of the diagram surely is the surface versus depth circulation.
For what it’s worth, this is being addressed on the RC thread: http://www.realclimate.org/index.php/archives/2015/03/whats-going-on-in-the-north-atlantic/?wpmp_tp=1#sthash.h9pYiyL8.dpuf
[Response: We are talking about the AMOC here, not the western boundary current which indeed is largely wind-driven, and more specifically about the thermohaline driven part of the AMOC. Its variations are controlled by density changes in high latitudes and not from the tropics. In paleoclimate, I would say it is well established by now that things like the Younger Dryas event or the climatic response to Heinrich events are driven by high-latitude buoyancy (mainly freshwater) forcing. Fans of the tropics as climate driver have tried but in my view failed to come up with alternative explanations for these events. -stefan]
It appears there’s an annoying ambiguity as to what is meant by “Gulf Stream System”. I posted two papers on yesterday’s thread which may shed some light:
Joyce and Zhang (2010), On the Path of the Gulf Stream and the Atlantic Meridional Overturning Circulation: http://journals.ametsoc.org/doi/full/10.1175/2010JCLI3310.1
Abstract. The Atlantic meridional overturning circulation (AMOC) simulated in various ocean-only and coupled atmosphere–ocean numerical models often varies in time because of either forced or internal variability. The path of the Gulf Stream (GS) is one diagnostic variable that seems to be sensitive to the amplitude of the AMOC, yet previous modeling studies show a diametrically opposed relationship between the two variables. In this note this issue is revisited, bringing together ocean observations and comparisons with the GFDL Climate Model version 2.1 (CM2.1), both of which suggest a more southerly (northerly) GS path when the AMOC is relatively strong (weak). Also shown are some examples of possible diagnostics to compare various models and observations on the relationship between shifts in GS path and changes in AMOC strength in future studies.
Ezer (2015), Detecting changes in the transport of the Gulf Stream and the Atlantic overturning circulation from coastal sea level data: The extreme decline in 2009–2010 and estimated variations for 1935–2012: http://www.ccpo.odu.edu/~tezer/PAPERS/2015_GPC_AMOC_SL.pdf
Abstract. Recent studies reported weakening in the Atlantic Meridional Overturning Circulation (AMOC) and in the Gulf Stream (GS), using records of about a decade (RAPID project) or two (altimeter data). Coastal sea level records are much longer, so the possibility of detecting climatic changes in ocean circulation from sea level data is intriguing and thus been examined here. First,it is shown that variations in the AMOC transport from the RAPID project since 2004 are consistent with the flow between Bermuda and the U. S. coast derived from the Oleander measurements and from sea level difference (SLDIF). Despite apparent disagreement between recent studies on the ability of data to detect weakening in the GS flow, estimated transport changes from 3 different independent data sources agree quite well with each other on the extreme decline in transport in 2009–2010. Due to eddies and meandering, the flow representing the GS part of the Oleander line is not correlated with AMOC or with the Florida Current, only the flow across the entire Oleander line from the U.S. coast to Bermuda is correlated with climatic transport changes. Second, Empirical Mode Decomposition (EMD) analysis shows that SLDIF can detect (with lag)the portion of the variationsin theAMOC transport that are associated with the Florida Current and the wind-driven Ekman transport (SLDIF-transport correlations of ~0.7–0.9). The SLDIF has thus been used to estimate variations in transport since 1935 and compared with AMOC obtained from reanalysis data. The significant weakening in AMOC after ~2000 (~4.5 Sv per decade) is comparable to weakening seen in the 1960s to early 1970s. Both periods of weakening AMOC, in the 1960s and 2000s, are characterized by faster than normal sea level rise along the northeastern U.S. coast, so monitoring changes in AMOC has practical implications for coastal protection.
In sum, not nearly settled science and not being characterized as settled science in literature. Such notions are lost on people who think they have it all figured out though, so as you were I guess — it’s been one heck of a good farce so far.
Not that I agree with Manns claims, but what in the world has a 5 year old NASA study have to do with today?
One must be wrong. You choose which.
Rud, if I wanted a snarky response, I would have posted on a warmist site.
RD, was not so intended. Was intending only to point out a starker ‘science is settled’ reality. Mann’s 2015 paper say unprecedented slowing since 1975, and getting worse owing to Greenland melt from CAGW. Willis 2010 NASA paper, based on calibrating satellites to ARGO, says probably accelerating maybe 15 % since 1993. Both cannot be true. Somebody is just plain wrong.
The above example is one of hundreds where the in context climetgate emails support the assertion that CAGW research is deeply corrupt.
So Brandon, is tree ring data used as a proxy for the AMOC more accurate then direct measurements from a fixed buoy system?
.
Snarky questions get snarky responses, but you knew that, so let’s just cut to the chase.
If a 5 year old NASA study has nothing to do with today, then should we just toss all NASA data as being out of date ?
I didn’t read it as a snarky question, and Roy and Rud both made it clear that their respective comments were not to be take as snark.
I’m all to happy to snark, because once again you bozos can’t figure out when to accept data from NOAA/NASA and when to throw it under the bus.
That was a weak attempt to elicit a response…. care to try again ?
[trimmed]
[Please do not insult all the honest working Bozo’s in the world by comparing their efforts to climate scientists in that manner. .mod]
u.k.(us),
Blog policy notwithstanding, I find myself somewhat bereft of alternate superlatives. I don’t know what to tell you. How would you describe a community with such a visceral Mann-hatred that AGW evidence they’d normally reject (ARGO) every other day of the week is used to in a polemic to support of the #1 Article of Faith: The Hokey Schtick is a @ur momisugly#$%ing LIE?
Clowns in oversized red footware with their shoelaces tied together doing pratfalls and face-plants in a manner that makes the Keystone Cops look competent and the Three Stooges look non-violent was the first image which came to mind. Try as I might, I just can’t shake it … virtually every post is more ridiculously incoherent and dissonant than the last. I’m almost out of popcorn and cotton-candy.
Yes, Mann’s Hokey Stick is a repeatedly debunked lie.
Next question?…
Mod and Brandon Gates:
I was just trying to play nice, I knew the “bozo” was just a throwaway.
Understood ?
You’ll know when I stop playing.
u.k.(us),
I didn’t take particular umbrage either. Weird that you got clipped and I didn’t.
Penny for your thoughts on my actual point. The silence is rather deafening.
dbstealey,
None. You hit that pitch out of the park on the first swing.
Brandon you ask:
“Penny for your thoughts on my actual point. The silence is rather deafening.”
===============
A thousand pardons, but which point are you speaking of ?
u.k.(us),
lol, exactly. Any other day of the week, Josh Willis of JPL trumpeting the “amazing accuracy” of ARGO would be ruthlessly derided as a kool-aid serving AGW alarmist. Exception: when ARGO “proves” that one Michael E. Mann of Penn. State is wrong.
Actually Brandon, without proper error bars and proper accounting for the geographical location of the Argo floats, we likely know less then we think we know. (Which you admit to above in a post above, not worth searching for) Was Mann’s study primarily based on the Argo observations?
Drive by insults to the entire disparate WUWT community are a simple expression of your immaturity.
You hit that pitch out of the park on the first swing.
Thank you.
Some thoughts are simply expressed. Like E=MC^2.
David A,
Compare:
To:
[hums] “One of these things is not like the other …”
Of course not. Besides it’s so much more effective putting words in someone’s mouth when you don’t quote them directly.
You mean Stefan Rahmstorf’s study? Judge for yourself from what has already been quoted: Here we present multiple lines of evidence suggesting that this cooling may be due to a reduction in the AMOC over the twentieth century and particularly after 1970.
If that doesn’t get it, this may help:
http://www.rare-posters.com/2865a.jpg
Hand-waving insinuations of “admissions” you’re too lazy to quote directly followed up with lame taunts are a glaring indication of your lack of a leg to stand on. Your leadoff self-contradiction was a brilliant touch.
Brandon Magoo, you done it again.
David A says, ,
“
Actually Brandon, without proper error bars and proper accounting for the geographical location of the Argo floats, we likely know less then we think we know.
and david a also said,
“Argo position and drift is very different and very simple to ascertain compared to measuring the mass of the ocean to a T change.
Brandon using his great intellect,[hums] “One of these things is not like the other …”
———————————————————————————————————–
Silly Brandon there is no contradiction if read in context. We know the Argo position very well. Incorporating their ever changing position into a GAT of the entire ocean is not simple in the least. So the first statement refers to the proper method of accounting for determining a GAT with ever moving instruments. On the surface stations moves require an adjustment. So Brandon, perhaps it is not me that needs a reading primer.
————————–\
Brandon continues to bloviate, quoting my question.
Was Mann’s study primarily based on the Argo observations?
Brandon responds,
“You mean Stefan Rahmstorf’s study? Judge for yourself from what has already been quoted: Here we present multiple lines of evidence suggesting that this cooling may be due to a reduction in the AMOC over the twentieth century and particularly after 1970″
————————————————————
No Brandon misunderstandeni, I meant what I said precisely. I was making a point to your dense brain cells, that it is likely that direct observations are better then proxy based models that disagree with direct observations.
Brandon, I simply did not consider your post on this thread acknowledging the limitations of ocean flow
science in its current state would be something I needed to repeat to you as it was only a short time ago.
I think you ended with ” In sum, not nearly settled science and not being characterized as settled science in literature. Such notions are lost on people who think they have it all figured out though, so as you were I guess…”
=============================
Once again Brandon Misunderstandin,
you prove my point that you completely fail to understand the post normal nature of this,” not nearly settled science ” which is being used to justify statist goals of central power and political authority to pick the common man’s pocket.
.
Brandon for you, an example of some background on Mann and his anti science, reposted from “real Science”
Here is a graph (to year 2000 on right) that has been BURIED by the Alarmists.
….Steve McIntyre notes that one of the “screened out” datasets just happens to be the one with the best resolution and the greatest duration – the Law Dome Oxygen 18 data set (from Antarctica)….
McIntyre adds:
Oxygen isotope series are the backbone of deep-time paleoclimate. The canonical 800,000 year comparison of CO2 and temperature uses O18 values from Vostok, Antarctica to estimate temperature. In deep time, O18 values are a real success story: they clearly show changes from the LGM to the Holocene that cohere with glacial moraines.
On its face, Law Dome, which was screened out by Gergis and Karoly, is an extraordinarily important Holocene site as it is, to my knowledge, the highest-accumulation Holocene site yet known, with accumulation almost 10 times greater than the canonical Vostok site. (Accumulation is directly related to resolution: high accumulation enables high resolution.) The graphic below compares glacier thickness for some prominent sites for three periods: 1500-2000, 1000-1500 and 0-1000. its resolution in the past two millennia is nearly double the resolution of the Greenland GRIP and NGRIP sites that have been the topic of intensive study and publication.
Given the high reliance on O18 series in deep time, one would think that paleoclimatologists would be extremely interested in a publication of the Law Dome O18 data and be pressuring Tas van Ommen on this point.
…
But despite the apparent opportunity offered by Law Dome, there has been virtually no technical publication of a high-resolution O18 or delD isotope series.
…
A Climategate email shows that Phil Jones asked about the omission of the Law Dome series from the IPCC illustration in the AR4 First Draft. I asked the same question about the AR4 Second Draft. They realized that the Law Dome graphic had an elevated medieval period and thus, including it in the graphic would – to borrow a phrase from the preparation of AR3 – would “dilute the message” and perhaps provide “fodder to skeptics”.
http://wattsupwiththat.com/2012/06/12/the-longest-most-high-resolution-most-inconvenient-paleoclimate-data-that-hasnt-been-published/
The above example is one of hundreds where the in context climetgate emails support the assertion that CAGW research is deeply corrupt.
So Brandon, is tree ring data used as a proxy for the AMOC more accurate then direct measurements from a fixed buoy system?
========================
duplicate post here, but now in the correct location.
.
Oh crap. Does this mean I MUST believe either NASA or M. Mann? I pass.
The thing about the 2010 paper is that NASA used actual measurements of the real world. Yes, they used what one could call data rather than computer simulations and observational bias. Astounding! I was under the impression that it was against Federal Law to use actual measurements in Climate “Science”.
This development left me gobsmacked.
Climate Audit trashes Mann’s paper:
http://climateaudit.org/2015/03/25/reductio-ad-mannium/
I think I will drop by there to see how Brandon Misunderstandin is insulting them.
SkepticGoneWild, thanks for the link. The article isn’t very long and well worth a read.
I think it’s worth mentioning that the RAPID data show no significant slowdown in the Gulf Stream component of the AMOC mass transport. This is in contrast to the climate model predictions. I quote:
“Thomas et al. (2012) looked at how the components of the
AMOC changed during a warming scenario in a model sim-
ulation and found that the reduction of the AMOC was pri-
marily a reduction in southward flow of deep water balanced
by a reduced Gulf Stream with little change in the strength
of the gyre circulation, which appeared to be determined by
Sverdrup balance. This contrasts with our observations that
show no significant change in the Gulf Stream transport over
the 2004–2012 period when the AMOC is decreasing.”
So all this talk in the media of the Gulf Stream slowing NOW is the usual alarmist rubbish. Confusion over the terms ‘Gulf Stream’/North Atlantic Drift/THC/AMOC doesn’t help either. It allows people on both sides to make misleading claims. Mann picks up on this on his FB post to claim that Tom Rossby’s study does not contradict his findings but he is curiously reticent to mention/correct the misleading alarmist claims put forward in the media about the Gulf Stream slowing/stopping based directly upon his and Rahmstorf’s study:
https://www.facebook.com/MichaelMannScientist/posts/873222562733947
I’m not sure where the NASA study fits into this and how their measurements compare to RAPID’s but it seems obvious that the demise of the North Atlantic circulation is being greatly overplayed and as usual pinned on man-made global warming.
Having now read all these papers, easy. RAPID is seafloor to surface tethered buoys measuring T, salinity, and current velocity from top to bottom, at 26N across the entire Atlantic (roughly central Fl). NASA Willis was (iIRC) 47N, roughly Long Island, looking at mainlymthe Guld Stream northerly flow. Mann says he is looking mainly off the coast of Greenland where the THS arises. Ah, but the neck bone is connected to the backbone connected to the hipbone… So, by better than 2:1, Mann is just wrong on AMOC weakening.
ALL such changes in all-things-climate-related should been seen as part of a ‘natural cycle’ unless there is extraordinary evidence to believe otherwise.
Otherwise…
The IPCC and warmists make a big mistake when they rationalize that the fresh water melt from this current warming can affect ocean currents. The volume of melt back at the break up of the ice sheets running into the lowered sea levels of that period can not be duplicated under today,s conditions.
l don’t think its the gulf stream slowing down is what put europe into the last ice age.
What l think happened was that because North America started to became much colder its that what lead to the chilling in europe. Because as the ice sheets grew in America that would caused a lot of cold air to flow over the northern Atlantic. Which would have surly caused a cooling of the northern Atlantic, so reducing the amount of warm air coming off the Atlantic to keep europe mild. This in turn with a more zonal southern tracking jet stream flowing across the Atlantic. Which would have reduced the amount of warm air coming up from the mid Atlantic and increased the amount of blocking over northern most europe. ls what l feel triggered europe into the last ice age.
I think you are right on target.
[And I think you are banned for sockpuppeting – Anthony]
This Mann character has to be seen to be believed. In order to deflect criticism of his work, he says on the one hand that the Gulf Stream is quite distinct from what his study is looking at, which is the AMOC:
“What Rossby is measuring is largely associated with the wind-driven boundary current of the subtropical horizontal ocean gyre, the warm poleward current that hugs the coastline of the southeastern U.S., the current that *physical oceanographers* refer to as the “Gulf Stream”. This is rather different from what we are looking at, which is what oceanographers instead refer to as the “AMOC” and more specifically, the “thermohaline circulation” (sometimes also called the “conveyor belt”
But then he allows himself to be quoted as saying that it may be only a matter of DECADES before a permanent shutdown of the North Atlantic Gulf Stream occurs. His recent FB timeline is crammed FULL of links to articles and interviews with himself which are predicting catastrophic slowdown/shutdown of the GULF STREAM. Here’s just one:
http://ecowatch.com/2015/03/25/global-warming-slowing-ocean-currents-michael-mann/
Jaime, your pseudonym is Perry Mason? Good job, from a (IIRC) real RAPID scientist. Bravo.
You shall inherit the climate science world despite this transitional heresey. By all means, connnect with Dr. Judith Curry now that you have been ‘outed’ as someone honest. Regards.
+2
And thanks to Rud Istvan, Brandon Gates and others for an amusing (and enlightening) thread!
“Net types like to catfight about whether blogging is the Way Forward or
utter self-indulgence. Since it is almost certainly both at once,
blogging is quite the hot topic. ” — Bruce Sterling
Haha, thanks Rud, I’ll take that as a compliment without necessarily agreeing entirely! Much respect for Judith Curry.
Is Mann correct? Is the Rossby study a different area? What part of the AMOC did Mann measure, or model?
Mann & Rahmstorf did not measure any components of the AMOC flow – even their modern instrumental data merely infers the strength of the AMOC. What did they do?
“An AMOC index based on surface temperatures
We take the results of a climate model intercomparison to identify the geographic region that is most sensitive to a reduction in the AMOC (Fig. 1), which for simplicity we henceforth refer to as `subpolar gyre’, although we use the term here merely to describe a geographic region and not an ocean circulation feature. To isolate the effect of AMOC changes from other climate change, we define an AMOC index by subtracting the Northern Hemisphere mean surface temperature from that of the subpolar gyre.”
In other words, they used a climate model to investigate what pattern of ocean temperatures would be strong ‘evidence’ of man-made global warming affecting the AMOC, then they used this to define their own unique AMOC index! Furthermore, they used decidedly iffy proxy data to ‘measure’ SST of the NH and sub-polar gyre so that they could reconstruct AMOC.
They found a good correlation of their AMOC index with a MODELED AMOC stream function so presumed it must be fairly representative of AMOC as a whole but admit that:
“Despite the good correlation with the AMOC in the model, our SST-based index only provides indirect evidence for possible AMOC changes.”
So there you go; Mannian/Rahmstorfian climate science in action!
Thank you Jamie. I guess that for someone who removed the MWP without so much as a “How do you do” to the past papers supporting it, he can revolutionize this field as well, and I think he came up with another unseen in 1000 years or so claim in this study as well.
Josh Willis? Then I’m with Mann. It’s slowing.
That’s a great ad hom attack, though pointless. You are “with” Mann, no need for embellishment.
FWIW Mike Mann is probably better at oceanography than tree stuff.
Which is not to say he is great shakes at either.
In other news-
The “No tornadoes through March” line just got busted. A small (F1?) just cut through downtown Moore, OK and is lifting as i write this. Moore, Oklahoma has gotten the worst of it with several large and powerful storms in recent years. The infamous May 3, 1999 F5 tornado wreaked havoc through Moore and South Oklahoma City with the highest wind speeds ever recorded at 300+ mph. That storm damaged or destroyed over 8,400 homes and businesses and unfortunately, killed 50 people. Had it not been for the superb weather detection and warning system in Oklahoma, several thousand may have lost their lives, as that powerful twister was taking structures down to the bare ground and moving the debris elsewhere. It was not survivable above ground.
I would have figured that Oklahoma would have blown the “no tornadoes in March” for the rest of us. Lol!
Tulsa/Sand Springs had a good sized twister out of this storm, as well.
Moore should set up horizontal wind turbines. It gets “Torn” regularly.
3, 2, 1…
And Mann replies that the NASA paper is ‘pure scientific fraud’.
I just skimmed the thread on this paper over at Climate Audit. I was astounded to learn that the proxy data used on this study is the SAME proxy data that was used in Mann’s Hockey Stick. How does one reconstruct the AMOC from tree rings and lake sediments? I just cannot be bothered to read the paper to see what mental gymnastics have to be performed to justify that connection. Not only are proxies used when actual data is available, the proxy is….tree rings? I defy anyone to come up with an explanation as to how those proxies can POSSIBLY be a measurement of the AMOC.
I hope they don’t wind up getting their paper withdrawn. Leave it up for everyone to see.
I think Mann needs to publish a paper every now and then, and only has his old data to do it with.
Mann’s typical day at the office:
North Atlantic looks like it’s getting cold…hmmm..why don’t we drag out our old tree ring and lake sediment data and see if we can come up with something?
you never heard of tele-connections? (-;
Illustration also doubles as a Character description of the Democrats and Republicans.
I’m with the Cool current, I don’t bother none with that shallow warm stuff – seems a lot comes from the West coast of the U.S.
P.S X-marks the spot where Cthulhu lays dreaming in R’lyeh.
So we could call this a ‘prebuttal’. Curiously, Rahmstorf et al cite this very article in their References:
19. Willis, J. Can in situ floats and satellite altimeters detect long-term changes in Atlantic Ocean overturning? Geophys. Res. Lett. 37, L06602 (2010).
I wonder if they actually read it.
“norah4you
March 25, 2015 at 10:23 am
Now it only takes Willis to learn the true story of climate – there is neither a climate threat nor a risk for Gulf Stream slowing down….
Btw – back in 980 AD to 1341/43 Greenland had warmer climate. Min 1 and a media of 3 degree Celsius more than today.”
Greenland was warmer than today during the MWP,while concurrently Europe was also warmer than today .
Doesnt this example by itself negate R/M15?Where was the cooling of Europe?
Re ribbon of currents diagram at top.
How does the cold deep ribbon heading north to Alaska get heated for its shallower southward leg?
Seems t be a reasonable and good point.
I was wondering something else: I understood the Humboldt Current to be the largest source of deep upwelling on the planet, and as such creates the most productive fishery and marine ecosystem on Earth.
Why is this not considered part of the thermohaline circulation? Because it is not driven by variances in salinity?
Or, perhaps that ribbon diagram is not particularly accurate, nor complete?
Another thing, the current off the west coast of South Africa is ice-cold from Antarctic upwelling. That warm surface current would be pretty difficult given the direction of the prevailing winds in the Southern Oceans being West to East.