Guest post by Bob Tisdale
http://downloads.globalchange.gov/usimpacts/pdfs/climate-impacts-report.pdf
As noted in the title, it fails to address the multiyear effects of El Nino-Southern Oscillation (ENSO) events on global temperature.
Other than explosive volcanic eruptions, El Nino-Southern Oscillation events have the greatest impacts on global climate on annual and multiyear bases. The year-to-year global temperature impacts of ENSO events are clearly visible in a comparative time-series graph, Figure 1. Also visible are the overriding effects of the 1982 El Chichon and 1991 Mount Pinatubo volcanic eruptions.
http://i44.tinypic.com/144ag5f.jpg
Figure 1
The multiyear impacts of the 1986/87/88 and 1997/98 El Nino events on Northern Hemisphere Lower Troposphere Temperature (TLT) are clearly visible in the TLT Time-Latitude Plot available from Remote Sensing Systems (RSS). Refer to Figure 2 and 3, which are from my post “RSS MSU TLT Time-Latitude Plots…Show Climate Responses That Cannot Be Easily Illustrated With Time-Series Graphs Alone.”
http://i44.tinypic.com/16leq39.jpg
Figure 2
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http://i41.tinypic.com/2vwzmdj.jpg
Figure 3
A seldom-discussed, naturally occurring oceanic process called Reemergence (Refer to my post “The Reemergence Mechanism”) provides the mechanism by which the global oceans integrate the effects of ENSO events. And it only takes the cumulative effect of a very small portion (0.0045 or less than ½ of 1%) of the monthly ENSO signal, as shown in Figure 4, to reproduce the Global Sea Surface Temperature (SST) anomaly curve.
http://i42.tinypic.com/iom6ab.jpg
Figure 4
YET HOW MANY TIMES DOES THE USGCRP REPORT MENTION THE EL NINO-SOUTHERN OSCILLATION?
The USGCRP mentions “El Nino” nine times in the body of the 196-page report, but those references only pertain to global temperature on one occassion. The first reference, however, states that ENSO is independent of human activities.
On page 16, during a discussion Natural Influences, they wrote, “The climate changes that have occurred over the last century are not solely caused by the human and natural factors described above. In addition to these influences, there are also fluctuations in climate that occur even in the absence of changes in human activities, the Sun, or volcanoes. One example is the El Niño phenomenon, which has important influences on many aspects of regional and global climate.” [My emphasis.]
They acknowledged that ENSO is independent of anthropogenic influence. That’s significant.
On page 17, in the text of the comparative graph of “Global Temperature and Carbon Dioxide”, they wrote, “These year-to-year fluctuations in temperature are due to natural processes, such as the effects of El Niños, La Niñas, and the eruption of large volcanoes.” [My emphasis.]
Yet they fail to note the multiyear and cumulative effects of ENSO.
Page 36, during a discussion of Pacific Hurricanes, they write, “The total number of tropical storms and hurricanes in the eastern Pacific on seasonal to multi-decade time periods is generally opposite to that observed in the Atlantic. For example, during El Niño events it is common for hurricanes in the Atlantic to be suppressed while the eastern Pacific is more active. This reflects the large-scale atmospheric circulation patterns that extend across both the Atlantic and the Pacific oceans.” [My emphasis.]
That quote is important in many contests. Much can be inferred from it. Yet they fail to acknowledge the multidecadal epochs when El Nino or La Nina are dominant. These epochs are visible in a time-series graph of smoothed NINO3.4 SST anomalies, Figure 5.
http://i43.tinypic.com/33agh3c.jpg
Figure 5
On page 38, under the heading of Snowstorms, they wrote, “The northward shift in storm tracks is reflected in regional changes in the frequency of snowstorms. The South and lower Midwest saw reduced snowstorm frequency during the last century. In contrast, the Northeast and upper Midwest saw increases in snowstorms, although considerable decade-to-decade variations were present in all regions, influenced, for example, by the frequency of El Niño events.” [My emphasis.]
And again, they infer multidecadal influences of ENSO, but the USGCRP have failed to account for it in their attribution of global temperature change.
There are further references of El Nino and La Nina events on pages 81, 147, 148, and 152, as they pertain to tuna stock, droughts, coral reefs, and coastal currents. No need to repeat those in this post.
CLOSING
Like the IPCC, the USGCRP either fails to accept the significant multiyear and cumulative impacts of ENSO on global temperatures or they chose to ignore them in their presentation of the causes of global temperature change.
Posted by Bob Tisdale at 8:42 PM
Leif Svalgaard (07:10:38) : “This is just some wiggle matching that is not convincing or even comprehensible. ”
Consider this. The Earths atmosphere is characterized by change in all its attributes according to latitude. The parameters that drive the latitude at which sea surface warming occurs, change over time. In the nature of things, ‘wiggle matching’ identifies dynamics that correlation will fail to identify.
The latitude that warms is not just the equatorial zone. Warming at 20-30°S usually precedes that at the equator and as the southern stratosphere/troposphere has warmed over the period of record the latitude where warming can be observed, has shifted further southward. Warming rate varies with longitude.
This latitudinal variation is abundantly apparent in the variability of the climate of southern Chile, in the change in its vegetation and its glaciers over time. Here we must have a geological perspective in terms of the time involved. Then we see the potential for long term climate change in the ENSO phenomenon.
The change in the ozone content of the atmosphere is not documented as you well know. But, the temperature of the stratosphere is, in broad terms, a very good proxy for its ozone content. And the temperature is very well documented. In this instance ‘broad terms’ is not a problem. Peak temperature in the stratosphere relates to warming of the sea, usually between the equator and 40° south. The reaction in the northern hemisphere is much less noticeable and much less correlated. There are obvious reasons for this. Hence the ‘Southern Oscillation”.
If the scale used minimizes the fluctuation to the point where you must describe it as a ‘wiggle’ it its easy to change the scale, but instead of one picture we finish up with five.
One take home message. The devil is in the detail. Close observation is necessary.
Here is a nice little paper on the production of nitric oxides in the auroral oval and its relationship with the Earths magnetic field, irradiance and geomagnetic activity.
The northern auroral region as observed in nitric oxide
C.A. Barth, D.N. Baker, and K.D. Manko_
Laboratory for Atmospheric and Space Physics, University of Colorado at Boulder
S.M. Bailey
Center for Atmospheric Sciences, Hampton University, Hampton, VA
Abstract. The distribution of thermospheric nitric oxide
in the northern polar region has been measured from the
Student Nitric Oxide Explorer (SNOE). A polar image of a
one-year average at 106 km shows the maximum density lies
between 60_ and 70_ N geomagnetic latitude. The density
around this auroral oval varies as a function of longitude
with the larger densities occurring at western geomagnetic
longitudes. A polar image of a second year of observations
demonstrates the same latitudinal-longitudinal density distribution
indicating that the asymmetry is a persistent property
of the auroral region. For a period of high geomagnetic
activity, the nitric oxide observations indicate that the flux
of precipitating electrons at 90_ W geomagnetic longitude the auroral oval.
Would you also deny the connection between nitrogen oxide concentration and the flux of ozone concentration in the stratosphere. Might as well go the whole hog while you are at it.
Kim,
Omnipresent as usual. Valid comment.
Leif; climate science is at such a state that “wiggle matching” is where we must start. Climate science is so messed up, that the basic observations that Erl and the rest of us do are necessary. We have no first principles to work from. All established first principles are contradicted by observations. So we have to start from the bottom, note a pattern, determine a plausbile theory, and then test it with the rest of the data. How else do you think we can investigate climate change? I agree, and I think Erl would agree, that each graph alone proves nothing. They indicate plausible ideas, and collectively, they represent a theory. Trying to establish a causation for ENSO is far too complex, involving too many dynamic processes to be proven with a graph – otherwise, the cause of ENSO would already be known. I personally withhold judgment on Erl’s theories, but his graphs do consider careful investigation. You can’t expect perfect correlation when trying to explain ENSO. Also, if you know a source of 03 data, please give a link.
Now something we agree on-
Looking through the massive NIPCC report, I’m disappointed by the focus on the solar cycle. This relentless pursuit of solar cycles is almost as unphysical as enhanced greenhouse theory. Looking at the oceans to determine where global change begins, and looking at the atmosphere to understand how it deals with heat and if it influences the oceans, requires a non-global outlook. Understanding variation by latitude, longitude, and altitude is required, and the “global average” is only understood once we can explain what aspects of the global average were driven by what regions and how. That’s how you go from observations to causation. And it takes a lot of wiggle-matching.
erlhapp (08:56:05) :
The change in the ozone content of the atmosphere is not documented as you well know.<i?
Of course it is well known, as the O3 concentration can be calculated rather precisely from the F10.7 flux which has been measured accurately since 1947.
One take home message. The devil is in the detail. Close observation is necessary.
The obfuscation thrives on irrelevant details.
Here is a nice little paper on the production of nitric oxides in the auroral oval and its relationship with the Earths magnetic field, irradiance and geomagnetic activity.
Yet another introduction of irrelevant detail. What happens at 105 km height is not important for the SST.
kim (07:39:41) :
The focus is blurred from the complexity of the relationship. The devil and the truth are in the details. Carry on, you two.
The relationship has not been demonstrated and the blurred focus allows the carrying on of a barren discussion, like the issue of ‘Elvis on Mars’.
Bob Tisdale (08:00:58) :
Sorry. Erl Happ’s areas of study are outside of mine.
Erl’s has to do with the causes of ENSO. I was then mistaken about what you are studying. In you many posts on this I see very often the word ‘mechanism’, but now you are saying that you have no interest or knowledge of any mechanisms. Just shows how difficult it is to communicating even simple things.
Leif Svalgaard (09:37:16) :
erlhapp (08:56:05) :
The change in the ozone content of the atmosphere is not documented as you well know.
Of course it is well known, as the O3 concentration can be calculated rather precisely from the F10.7 flux which has been measured accurately since 1947.
Carl, Erl, Bob and Leif, please would you take a look at this graph I’ve produced and tell me whether it’s relevant. I think it might tie in well with Bob’s PWP hidden heat and re-emergence ideas, and with Erl’s solar ideas too.
http://s630.photobucket.com/albums/uu21/stroller-2009/?action=view¤t=ssa-sst-ssn.jpg
I know I clown around and joke on here a lot but I honestly think I may be onto something here.
Thanks guys
Tallbloke –
SSN likely has some contributiont to modern warming. But I just don’t see much. The fall from the 19th to the 20th solar cycle was massive but produced no cooling. And ENSO activity wasn’t especially high to balance it out. Then again, I could be wrong. Also, I’ve seen people graph 11-year smooths of SSN and ENSO. If you build in a lag, there seems to be a post 1950-correlation. But a lag doesn’t make sense (nor does a smooth)because ENSO’s variation isn’t a nice smooth curve. The shifts of ’57 and ’76 were abrupt, and they drive the correlation. It wouldn’t make sense for solar energy to store up in the ocean and then bam! a few years later we see a climate shift in a matter of months. If the sun is influencing ENSO, there should be no lag.
Carl Wolk (10:56:46) :
Tallbloke –
SSN likely has some contributiont to modern warming. But I just don’t see much.
Hi Carl, it’s not so much SSN in red I want you to look at, but the cumulative total of sunspot area below. The build up and sudden release of peaks in SST coincide with the ends of el nino dominant periods around 1880, 1940 and 1998. The 60year oscillation overlays the underlying cumulative solar trend it seems to me.
I agree with what you and Bob say anout the PWP, but in the end, the energy is coming from the sun (where else?). The issue is the mysterious way it hides in the climate system and manifests in the 30 up 30 down 60 year cycles. I think my graph goes some way to explaining that. The downslope in the cool la nina dominated period from 1880-1910 is steeper than the fall in my cumulative solar index. Then an el nino dominated phase takes over while the solar accumulation is bottoming out. It then crashes at 1945 and we get a cool phase as the solar accumulation is picking up again in the background.
Idon’t see why there couldn’t be both fairly immediately felt effects of solar energy via cloud mediation, as well as longer term buildup and releases such as the big events in 1998. It just means there’s more than one type of oscillation going on, with moe than one factor involved. Not everything is splendidly vacuum isolated in the solar system.
Leif Svalgaard: You wrote, “Erl’s has to do with the causes of ENSO. I was then mistaken about what you are studying. In you many posts on this I see very often the word ‘mechanism’, but now you are saying that you have no interest or knowledge of any mechanisms. Just shows how difficult it is to communicating even simple things.”
The communication problem was most likely mine. Excuse the brevity of my earlier reply.
My posts at my website and here have to with topics that are easy for the average person (me) to grasp. I use readily available data, primarily from NOMADS and the KNMI Climate Explorer, so that anyone with a spreadsheet and the want to duplicate my work can do so.
Though I do post on other topics, my primary areas of interest are the OCEANIC process of ENSO and the aftereffects of ENSO as they relate to SST, LST, and TLT. One of those aftereffects is a process called reemergence, with which I recently used the word mechanism.
Erl Happ (and Leif):
Erl, as far as I can tell, you attempt to illustrate the causes of ENSO through multitudes of interwoven atmospheric processes. As I wrote in my earlier comment to Leif, your research is outside of my areas of interest. Personally, I find your posts and your comments here at WUWT confusing. Part of that could be my own understanding (or lack thereof) of the subject matter and part could be my own findings. I have written a few posts about cloud amount and cloud cover, and those posts illustrated that cloud amounts in the tropical Pacific are for the most part responses to ENSO.
Regards.
tallbloke: Regarding your comment that starts with, “Carl, Erl, Bob and Leif, please would you take a look at this graph I’ve produced and tell me whether it’s relevant.”
I assume you’re thinking the running total of TSI would serve as a proxy for heat input to the PWP. Have you restarted the running total of TSI after each El Nino (assuming La Ninas are aftereffects of El Ninos), in effect showing the “heat input” between El Nino events? That way you could see if the peaks of the running total in any way replicate the intensity of the subsequent El Ninos. Also, you may need to account for the impacts of tropical volcanic eruptions.
tallbloke, it would be helpful if you were to explain the mechanism of the correlation you appear to be showing on your graph. Otherwise we are back to the goddess in the cave again. You seem to want to keep going back to an SSN-driven mechanism but I can’t come up with any reasonable mechanism (other than the goddess in the cave or perhaps the Sun moving closer then further away from Earth. Please elucidate.
Erl, Bob, et many al; cause and effect are much mingled in many of these processes; just as the clouds seem to play both roles, so might many of Erl’s ‘interwoven atmospheric processes’. It is indeed a magnificent hall of mirrors reflecting a meta-Rube Goldberg device.
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Leif Svalgaard (09:37:16) :
erlhapp (08:56:05) :
“The change in the ozone content of the atmosphere is not documented as you well know.<i?
Of course it is well known, as the O3 concentration can be calculated rather precisely from the F10.7 flux which has been measured accurately since 1947."
Just plain wrong. The ozone content of the lower stratosphere/upper troposphere is determined by the drift rate from zone of creation. The ozone content at any level is under chemical control. Ozone persistence is dependent upon temperature, the moisture content of the air and the influence of erosive nitrogen compounds brought into circulation in a dramatic fashion in the polar vortexes.
The sad thing is, you know its wrong, but when you want to deny a thesis, anything goes.
tallbloke (09:53:18) :
There may be a causal relationship but the mechanism must be explained. I am with Pamela on this.
Bob Tisdale (14:14:13) : “Erl, as far as I can tell, you attempt to illustrate the causes of ENSO through multitudes of interwoven atmospheric processes. As I wrote in my earlier comment to Leif, your research is outside of my areas of interest. Personally, I find your posts and your comments here at WUWT confusing. Part of that could be my own understanding (or lack thereof) of the subject matter and part could be my own findings. I have written a few posts about cloud amount and cloud cover, and those posts illustrated that cloud amounts in the tropical Pacific are for the most part responses to ENSO.”
Thanks for the honest feedback Bob.
I begin with the proposition that the changing flux of solar energy into the ocean governs sea surface temperature. Not unreasonable? In simpler language, when a cloud gets in the way its cooler at the surface. Of course the real world is not so simple. Clouds are far more abundant in bodies of warm moist air traveling away from the Equator. When I want to know when it is going to rain I look at this: http://www.coaps.fsu.edu/~maue/extreme/gfs/current/plan_water_000.png
That record of total precipitable moisture is worth contemplating. Copy, paste and watch.
We are currently at the tail end of a cycle of warming in the tropical waters. This particular cycle has been going on while the SOI has been in positive territory (La Nina) and its not going to the negative for very long. I know this because SST is predominantly determined in the southern hemisphere by the change in near invisible upper troposphere ice cloud (between the equator and 40°S) that varies with local 200hPa temperature. In turn, 200hPa temperature depends upon local ozone content and this depends upon the processes that govern the ozone content of the lower stratosphere.
The ozone content of the lower stratosphere is governed, not by ultraviolet radiation to any great extent, but the flux in ozone concentration due to ‘dynamical processes’…. a loose term for the processes I referred to in my last post to Leif and then some more as well. The circulation of the air in the stratosphere is very important as a determinant of ozone levels at 200hPa. Ozone is created in the upper stratosphere by short wave energy splitting the oxygen molecule.
There is one way to be sure of what is going on. It is by exhaustive analysis of atmospheric temperature at all levels.
Let me describe my modus operandi. I start at the lowest level of the atmosphere, lets say 850hPa. I download the data for each 10° of latitude from pole to pole using NCEP/NCAR. I have formula to convert the table quickly into a vertical presentation with a running 12 month mean. I then graph the 18 lines together. (all this can go on one spreadsheet if you use the available horizontal space economically). If there is anything of interest in terms of anomalous behaviour I will focus on the latitudes concerned. I do this for each level that NCEP/NCAR documents between the surface and 10hPa.
I do the same for vertical sections of the atmosphere where it seems useful. This is critically important in the tropics, the mid latitudes and the poles.
If you do this the first thing you notice is the enormous difference between the two hemispheres of the Earth. That is a good starting point.
Knowledge does not come cheaply. The answers are not simple. Kim’s message is relevant.
I am doing what might be called ‘historical climatology’. You are too. The answers we seek are in the climate record.
I now quote Carl who is very much ‘on the money’.
“Looking at the oceans to determine where global change begins, and looking at the atmosphere to understand how it deals with heat and if it influences the oceans, requires a non-global outlook. Understanding variation by latitude, longitude, and altitude is required, and the “global average” is only understood once we can explain what aspects of the global average were driven by what regions and how. That’s how you go from observations to causation. And it takes a lot of wiggle-matching.”
Observation is king. The ability of the Australian aboriginal to track peoples movement by looking at the ‘tracks’ they have left in the country, is legendary. In the same way, if you get to know the atmosphere as ‘your country’ via the existing climate record you have half a chance of working out what is going on.
So erl, I think you are saying that modulation of ozone is not so much a Sun mediated thing, but an Earth Atmosphere thing. I have been watching ozone for quite some time and noticed right off that ozone concentration changes from daylight hours to nighttime hours. I also have noticed that ozone is not well mixed in the atmosphere. These observations, along with Leif’s tutoring, made me realize that ozone variation is more caused by the Earth itself than the Sun over the long term (over several Sun cycles). So it seems that while Sun cycles correspond somewhat with ozone development, its shorter term variation is an Earth bound phenomenon. Would you agree?
The above comment on ozone variation was a bit confusing on my part. There is a direct relationship to overall ozone ups and downs that can be calculated based on the Sun’s cycles. However, the globby here and there, and thick and thin nature of ozone is an Earth bound phenomenon. So once again, we are back to the Sun being a predictable source of cycles, but the Earth is the source of the not-so-predictable weather pattern variation chaos we are trying to understand.
Pamela,
The really critical observation is the chemical control of ozone via the interaction of various oxides of nitrogen originating in the mesosphere/thermosphere with ozone in the stratosphere.
The concentration of these erosive compounds varies with solar activity, both irradiance and geomagnetic activity.
The most aggressive interaction zone is the southern vortex over Antarctica.
The mixing that occurs on short time scales (days, weeks) measurably affects ozone content in the lower stratosphere into the mid latitudes. This has been measured in the northern hemisphere.
A google search on ‘nitrogen oxides geomagnetic activity’ will bring up heaps of material.
I agree with the statement in your last post. The atmosphere mediates the ozone response at the equator. Prime entry point is the poles. Secondary entry points the upper global stratosphere where the location of the stratopause (where temperature ceases to rise with elevation) is under the control of this phenomena.
Looked at another way the stratosphere is the ozone shield with the most protected part of it above the equator. Paradoxically, the ozone levels in this zone are under attack at the equator by moisture lifted through the tropopause. Ozone is highly soluble in water. There is also the phenomenon of the biennial shift in wind direction from East to west above the equator and its affect on downward drift phenomena.
End of the day, when temperature rises at 20hPa it reflects increasing ozone content in the lower stratosphere/upper troposphere. This, per medium of changing cloud cover in the upper troposphere drives the Southern Oscillation.
Its actually very simple and you are onto it.
Pamela
Looking more closely at this sentence of yours: ” but the Earth is the source of the not-so-predictable weather pattern variation chaos we are trying to understand.”
Its the sun and the Earth together. The atmosphere modulates the fashion in which the solar stimulus plays out. If you look at the data between the poles and the equator and between the stratopause and the tropopause this is the mechanism that is apparent.
The atmosphere is appallingly thin and somewhat lopsided. The temperature record shows the forces at play.
erlhapp (18:09:10) :
tallbloke (09:53:18) :
There may be a causal relationship but the mechanism must be explained. I am with Pamela on this.
Thanks Erl,
The idea of graphing the solar data in a cumulative way only occurred to me yesterday so I haven’t had much time at it yet. As Carl Wolk said, we’re attempting to rebuild the smoking ruin of climatology from the seabed up, and at this stage, wiggle matching of various potentially interesting correlations is where we’re at with some aspects of the heat retention puzzle.
Pamela Gray (15:33:23) :
tallbloke, it would be helpful if you were to explain the mechanism of the correlation you appear to be showing on your graph. Otherwise we are back to the goddess in the cave again. You seem to want to keep going back to an SSN-driven mechanism but I can’t come up with any reasonable mechanism (other than the goddess in the cave or perhaps the Sun moving closer then further away from Earth. Please elucidate.
Hi Pamela, at the moment I’m working from the other end inwards, because current opinion from the big guns like Leif Svalgaard seems to discount most of the potential electromagnetic carriers for a mechanism.
Teasing out which parts of the electromagnetic spectrum affect which aspects of climate feedback in observable ways and to what extents is what this discussion is about, and I see various investigators such as Bob, Erl, Carl, Willis, and Stephen Wilde grappling with those issues.
If we start from the basis of “well it was damn cold in the c17th when solar activity was very low, warmer in the C18th when it picked up again, cooler in the c19th when it dropped again, and very warm in the latter half of the C20th when it built up to a several thousand year high, then we can maybe accept as a general principle that solar activity affects Earth temperature through a variety of observed and partially understood phenomena. We need to find useful proxies for overall input to the climate system, and with the reservation that my graph is an initial preliminary effort, looking at the sunspot area data as a cumulative series seems to me not an unreasonable idea, given Bob’s elucidation of the way heat builds up in the subsurface ocean in hitherto unmeasured ways.
Before we can work out just what the Goddess is up to in that cave, we need to recognise that she’s there and discover her names and parentage so we can ask her directly.
Bob Tisdale (14:40:49) :
I assume you’re thinking the running total of TSI would serve as a proxy for heat input to the PWP. Have you restarted the running total of TSI after each El Nino (assuming La Ninas are aftereffects of El Ninos), in effect showing the “heat input” between El Nino events? That way you could see if the peaks of the running total in any way replicate the intensity of the subsequent El Ninos. Also, you may need to account for the impacts of tropical volcanic eruptions.
Hi Bob, as I said to Erl, the idea to look at cumulative solar activity just came to me in a flash yesterday, so, no, I haven’t worked periodic ‘resets’ to the running count, but it’s an excellent suggestion, thanks for the idea. One thing that occurs immediately is that in your account, a lot of the warm water spread out by el Nino recirculates and returns to the pacific warm pool. If we had an idea of the proportion of heat energy doing that following historical el Nino events, it would help me decide on the appropriate ‘offset’ to apply to the count, rather than hitting it with a complete ‘reset’.
Volcano’s are mavericks in the climate quantification puzzle, because single unpredictable events can have large effects and spoil the prediction party. Nonetheless, there are also interesting correlations between overall longterm volcanic activity and solar activity lurking in the peer reviewed literature. We get more volcanic activity when solar activity is low, as we are seeing at the moment with the 20 or so biggish active volcanos belching and smoking around the world.
Thanks again for your suggestions, I’ll sit back and have a think about how to refine the cumulative model.
Carl Wolk:
The article mentioned by Carl Wolk “how enso rules the oceans” raises the question whether Arctic Sea Ice Extent is correlated with ENSO with a delay of 9 – 10 years.
Long term historic ice ixtents in the Nordic seas http://www.climate4you.com/SeaIce.htm show a modest correlation (~0.3) with ENSO at a delay of 9 years for the earliest record period covering 1860 – 1910. However the correlation is unconvincing over the longer Arctic Ice Extent record including the satellite record 1979 – 2009. A possible reason may be that the more recent ice extent is strongly affected by events such as Mt Pinatubo eruption. For example, a decrease in ice extent 9 years after the 86/87 El Nino event may be masked by cooling from the Mt pinatubo eruption in 1995/96, whereas the decrease in Arctic ice extent 9 years after the 97/98 El Nino suffers no such masking in 2007/07.
A mechanism that associates El Nino or ENSO events occuring 9 years prior to anomolies in the Arctic Sea Ice Extent could be the slow transport of El Nino induced West Pacific warming via the “ocean conveyer belt” (thermo haline circulation) to the North Atlantic. This would require a conveyer belt speed of about 0.1 m/s. This corresponds to some estimates of the speed of the warm surface current sections of the ocean conveyer across the Indian Ocean and up the Atlantic Ocean to the Arctic.
Has a possible correlation between Arctic Ice Extent anomolies and ENSO events been examined by anybody?
A broad introduction and some useful references to the subject of ozone dynamic via the polar vortex can be found here: http://www.appinsys.com/GlobalWarming/Ozone.htm
Bob Tisdale, thanks for your many efforts to communicate observational information about Earth’s oceans to a non-science-professional public (as well as to the amazing “minds” who comment here). I enjoy the way you make the info accessible in charts. I don’t know enough yet to comment; I have tried, but have had to erase them. However, I follow your blog and the research articles to which you link. On an intuitive basis, so much of what happens here on Earth seems to have to do with the amazing physics of water in all its forms. It seems that even W. Eschenbach’s brilliant Thermostat Hypothesis couldn’t work without the way H2O works. Do you have any opinion on Mark Denny’s How the Ocean Works re its scientific accuracy from your perspective? Do you have any (other) recommendations?
ian edmonds (00:49:51)
I have previously suggested elsewhere that the Arctic Circle is the final destination for Pacific waters previously warmed by El Ninos or cooled by La Ninas and that there might be a travel time of 9 or 10 years.
On that basis the 2007 Arctic melt would have been the last gasp of the 1998 El Nino and it is going to be about 2016 before the effect of the recent strong La Nina has maximum effect there.
In the meantime the weaker solar input should compound the effect of cooler waters reaching the Arctic.
I expect a slow increase in Arctic ice cover until at least 2017.
Ian –
I haven’t looked into it. However, heat transport to the Northern Latitudes has a strong ENSO signature, which can be seen in the North Pacific, North Atlantic and Northern lower tropospheric data. In fact, I don’t think many other variables (besides volcanoes) have been at play during the past 30 years, so I’d wager that ENSO has to be responsible for the recent reduction in ice.