From AUSTRALIAN NATIONAL UNIVERSITY
How El Niño impacts global temperatures
El Niño oscillations in the Pacific Ocean may have amplified global climate fluctuations for hundreds of years at a time
Scientists have found past El Niño oscillations in the Pacific Ocean may have amplified global climate fluctuations for hundreds of years at a time.
The team uncovered century-scale patterns in Pacific rainfall and temperature, and linked them with global climate changes in the past 2000 years.
For example, northern hemisphere warming and droughts between the years 950 and 1250 corresponded to an El Niño-like state in the Pacific, which switched to a La Niña-like pattern during a cold period between 1350 and 1900.
The new data will help scientists build more accurate models of future climate, said member of the research team, Alena Kimbrough, from The Australian National University.
“Our work is a significant piece in the grand puzzle. The tropics are a complicated, yet incredibly important region to global climate and it’s been great to untangle what’s happening,” said Ms Kimbrough, a PhD student at the ANU Research School of Earth Sciences.
“The current models struggle to reflect century-scale changes in the El Niño Southern Oscillation (ENSO).
“We’ve shown ENSO is an important part of the climate system that has influenced global temperatures and rainfall over the past millennium.”
The team measured trace elements and stable isotopes in stalagmites from the Indonesian island of Flores to reconstruct ancient rainfall, and compared it with records from East Asia and the central-eastern equatorial Pacific.
The El Niño Southern Oscillation is an irregular variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean. In one extreme it brings high temperatures and drought to eastern Australia and Indonesia, and the opposite extreme, known as La Niña, heavy rainfall and storms.
“In the past decade or so the rise in global temperature had a brief reprieve, the so-called warming hiatus, which can be partly attributed to a persistent La Niña pattern over that period,” Ms Kimbrough said.
The new work found periods of predominantly El Niño-like patterns for several hundred years that alternate with La Niña patterns, impacting on global climate over the last 2000 years.
“Until we can model this lower-frequency behaviour in the tropical Pacific, one can only speculate on how the warming will play out over the next few decades,” said lead author Dr Michael Griffiths from William Paterson University, in the United States.
The international team of scientists was led by Dr Michael Griffiths of William Patterson University in New Jersey, along with PhD candidate Alena Kimbrough and Dr Michael Gagan at the ANU, Professor Wahyoe Hantoro of the Indonesian Institute of Sciences and colleagues at the University of Melbourne and the University of Arizona.
The research is published in Nature Communications.
###
The paper: http://www.nature.com/ncomms/2016/160608/ncomms11719/full/ncomms11719.html
Western Pacific hydroclimate linked to global climate variability over the past two millennia
Abstract:
Interdecadal modes of tropical Pacific ocean-atmosphere circulation have a strong influence on global temperature, yet the extent to which these phenomena influence global climate on multicentury timescales is still poorly known. Here we present a 2,000-year, multiproxy reconstruction of western Pacific hydroclimate from two speleothem records for southeastern Indonesia. The composite record shows pronounced shifts in monsoon rainfall that are antiphased with precipitation records for East Asia and the central-eastern equatorial Pacific. These meridional and zonal patterns are best explained by a poleward expansion of the Australasian Intertropical Convergence Zone and weakening of the Pacific Walker circulation (PWC) between ~1000 and 1500 CE Conversely, an equatorward contraction of the Intertropical Convergence Zone and strengthened PWC occurred between ~1500 and 1900 CE. Our findings, together with climate model simulations, highlight the likelihood that century-scale variations in tropical Pacific climate modes can significantly modulate radiatively forced shifts in global temperature.
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In the past decade or so the rise in global temperature had a brief reprieve, the so-called warming hiatus, which can be partly attributed to a persistent La Niña pattern over that period
Must … keep … it alive ….
El Nino and La Nina cause perturbations in the evolution of the climate’s chaotic evolution. Who’d have thought that?
Gee, so the warming period at about 1000 CE and 100 CE happened in the southern hemisphere too. Who wudda thunk it? It was not just those mean nasty white guys in Europe after all.
“ “Until we can model this lower-frequency behaviour in the tropical Pacific, one can only speculate on how the warming will play out over the next few decades,” ”
I absolutely refuse to entertain this, and for good reason. There is a very smart scientist who knows tons about warming and he knows what part is man caused and what part is natural. This I know because I have read the writings of Michael Mann, the Distinguished Professor of Meteorology Director, Earth System Science Center at Pennsylvania State University. Therefore the entire article is suspect.
/sarc 😉
The warmest parts of the regional MWP were La Nina dominated. During glacial periods near permanent El Nino conditions exist. Here is an interesting study on centuries of very strong El Nino, around the very cold 1200 BC period for the mid latitudes that collapsed many civilisations, during one the strongest Arctic warming periods of the Holocene. Page 4:
http://www.clim-past.net/6/525/2010/cp-6-525-2010.pdf
More evidence that the science is nowhere close to being settled.
well, well. Go figure.
This study is indeed of huge importance – confirming that natural oceanic oscillations can serve up significant climate change over century and millenial timescales. Its significance should not be lost in the scrum of everyone pushing their own little ENSO story.
In other shocking-shocking news, the following La Niña may affect global climate fluctuations for hundreds of years at a time. No shit we’ll all freeze in a split second!
Following these “cool” news, so I’m resuming my CPU overclocking hobby to “make a change”.
/SARC
In Southern California we view the El Niño as warm and wet vs. La Niña as cool and dry, so it’s a lot easier to read when flopped vertically, and the colors still work. Properly inverted (Sorry Australia ;)) the Flores Speleotherm results really pop. Particularly obvious correlation with Hubert Lamb’s classic MWP/LIA chart.
I suspect we all immediately see that, but a picture’s worth a thousand words. Unfortunate that the results came from the Australian perspective rather than somewhere in the North.
In Australia, do you find stalactites on the floor?
Aren’t stalactites and stalagmites reversed down under?
“In the past decade or so the rise in global temperature had a brief reprieve, the so-called warming hiatus, which can be partly attributed to a persistent La Niña pattern over that period,” Ms Kimbrough said.
So, this is what, number 50-something on the list of explanations for the “hiatus”? The list of explanations for a halt in global warming…which, according to settled science, was itself supposed to be unaffected by anything other than CO2…am I missing something?
rip
Not a new excuse. I believe Trenberth used the cool Pacific excuse at some point in time. What these folks always omit is the overall effect if you go back prior to the hiatus. While La Nina conditions were predominate since 1998, they still haven’t offset the predominate El Nino conditions that started in 1976 and ran during the warming.
1) What orientation of plate tectonics distinguishes Warm from Cold signals? Movement Modeling?
2) How has potential magmatic activity been been distinguished form isotopic signatures associated with warmth?
We are told that “The team uncovered century-scale patterns in Pacific rainfall and temperature, and linked them with global climate changes in the past 2000 years.” That is fine but it has nothing to do with El Nino which they thoroughly misunderstand. According to them, “The El Niño Southern Oscillation is an irregular variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean……..The new work found periods of predominantly El Niño-like patterns for several hundred years that alternate with La Niña patterns, impacting on global climate over the last 2000 years.” All this is utter nonsense but it gets passed on from misinformed to misinformed individuals. First, ENSO is not an irregular variation of anything. It is a periodic oscillation of ocean water from side to side in the equatorial Pacific, powered by trade winds. Trade winds pile up warm equatorial water unto the Indo-Pacific Warm Pool, the warmest water in the oceans. When no more can be pushed up gravity flow in reverse begins. It takes the form of an El Nino wave that crosses the ocean from west to east and runs ashore in South America. There it splits and knows north and south along the coast. In the process it warms the air above it. That warm air then rises, joins the westerlies, and we notice that an El Nino has arrived. But any wave that runs ashore must also retreat. As the El Nino wave retreats, water level behind it is lowered.Cold water from below then wells up, to fill the vacuum and a La Nina has started. As much as the El Nino warmed the air that La Nina will cool it and the mean temperature will stay the same. That is why an El Nino has no effect on global mean temperature. Note also that they always come in pairs. It is an oxymoron to speak of an “El Nino-like” or a “La Nina-like” patterns. Hansen went the whole hog, declared the entire Miocene to be “El Nino-like,” and never looked back. You van do that when you are the boss but stupidity is stupidity, no matter who thinks they know otherwise. If you want a direct view of the ENSO oscillation all you need to do is to look at a NOAA or HadCRUT4 global temperature curve that has not been smoothed. It looks like it is covered by shark’s teeth. All the teeth you see are El Ninos and the valleys in between are La Ninas. Peak spacing is close to five years.
Javier, Bill
Ocean driven climate cycles of long duration are shown incontrovertibly in this study. This study shows an oscillation of about 1000 years wavelength. What links this to ENSO is fractality which is a signature of nonlinear dynamic systems. Fractality means that similar patterns, e.g. Warm/cold wet/dry oscillations occur on timescales from subdecadal to millenial. What we are seeing here is just a textbook example of fractal oscillation patterns in a nonlinear dynamic system. The oscillation is a Lorenz type butterfly wing oscillator / attractor which alternately hangs in one of two states, or wings – the el nino dominated and the la nina dominated.
https://en.m.wikipedia.org/wiki/Lorenz_system
What is interesting is that these Lorenz millenial oscillations are in different phase in different places. Inter hemispheric bipolar seesawing is evident. The paleo records seem to fall into three categories:
1 North hemisphere like
Flores, Sulawesi. Warm/dry in MWP, cool/wet in LIA.
2 Southern Hemisphere like: Galapagos; Cool/wet during MWP, warm/dry in LIA.
3. Chaotically switching between NH and SH regimes: Peru, Ecuador
“In the past decade or so the rise in global temperature had a brief reprieve, the so-called warming hiatus, which can be partly attributed to a persistent La Niña pattern over that period,” Ms Kimbrough said.
Que!? We’ve just had the Mother of all el Nino’s and she thinks we’ve had a brief reprieve … because of a minor la Nina … our temps have been influenced by the warm oceans offshore which have caused more westerly and north-westerly winds from the hot interior. A big la Nina is now reportedly on its way, the “reprieve” will become a full-on RETREAT in the coming months!
On millennial time scales, something big causes surface warmth to build or surface warmth to decrease. The Sun doesn’t vary that much so it can’t be the Sun. It has to be something much more variable and that absorbs and releases heat. Because it has to be huge in size, logically, that thing must be the oceans, which are able to store heat or release heat. My logic says that it can also do this over millennial time scales in order to have this grand seesaw behavior demonstrated in many proxies over the past 800,000 years. Here is why people dismiss it: We can’t actually “see” the long term pattern. The only thing generations “see” is what appears to be a flat noisy thing. But proxies all over the world show that it is not flat. The proxies in the ocean demonstrate wide swings, as do proxies on land. Since land cannot over long periods of time absorb and then release heat but water does, it is water wut dun it. That the oceans can be this mechanism is physically plausible due to both the properties of ocean water and its volume, interacting with other intrinsic factors such as Earth’s tilt towards the Sun, atmospheric patterns of large cell systems, land forms, overturning deep circulation, and the Coriolis effect on surface circulation.
+1
Oh yes it can be the Sun. The response of the Earth’s climate system to the Sun’s variability doesn’t have to be linear as you presuppose. Changes in UV radiation and ozone can be up to 10 times higher than changes in the total solar irradiation, and it is plausible that those changes at the thermosphere and stratosphere can translate to the troposphere causing changes in cloud cover that can affect the amount of solar energy that the oceans receive. Nothing of this is impossible or implausible as we simply do not know. So do not rush to scratch the Sun from your list. It can be the Sun.
Javier
O no it cant.
Pamela is right – its the ocean.
Looking to the sun for every tiniest wiggle of the climate wavetrain is no more intelligent than doing the same with CO2. Or to magnetic fields or planetary alignments.
Please write 100 times:
“THE OCEAN DRIVEN CLIMATE SYSTEM IS NOT PASSIVE, IT CHANGES BY ITSELF”
Science is content to accept astrology on the grand scale (Milancovic) but it treats with contempt anything lesser.
Vuc, did you mean to say Astronomy? Astrology has nothing to do with orbital mechanics.
ptolemy2,
Just because you say so.
You can go do it to yourself.
Gerard Bond noticed the strong correspondence between the millennial climate cycle and the millennial solar cycle in his landmark 2001 paper. Ignore it at your own peril.
http://www.euanmearns.com/wp-content/uploads/2016/05/Figure-3.png
Javier, both C14 and 10Be have climate affects in their signals. Therefore, if you use these indices as a solar measure to compare to climate proxies, you could state a case for auto-correlation. Great care must be taken to remove the climate signal from these solar indices before comparing them to the climate. Back in 2001, that care was not taken because it was not considered to be a big deal back then. The 2001 paper you refer to is therefore suspect.
Javier, Vuk
I perhaps overstated my case, I don’t doubt that solar and other astrophysical forcings influence climate, from Milankovich to shorter timescales. However it also is well established that oceanic circulation which strongly influences climate, posesses its own internal dynamic. It is a chaotic-nonlinear oscillatory system with its own emergent structure and pattern.
Thus I get frustrated by attempts to explain all climate fluctuations on all scales as arising from an external forcing. CAGW advocates are very bad at this, they make no allowance at all for internal dynamics.
There is a paradigm that can reconcile external forcing of the oceans and climate with internal oceanic dynamics. So one does not have to choose between one and the other. It is the periodically forced nonlinear oscillator. Such systems can be strongly or weakly forced. With strong forcing the system follows in lockstep with the forcing frequency. However in a weakly forced nonlinear oscillator the behaviour of the system can have a weak and complex relationship with the forcing wavetrain such that it can even be hard to see any relation between the two. Looking at the glacial-interglacial wavetrain in relation to Milankovich forcing, it looks like a mix of strong and weak periodic forcing. In particular the MPR where the frequency changed from obliquity paced to eccentricity paced, looks like a transition between strong and weak periodic forcing. Bearing in mind the fractality of nonlinear pattern formation, such forced dynamics are likely also present at timescales much shorter than Milankovich.
Pamela,
14C is affected by the carbon cycle and this has been known for over 5 decades, as proper carbon dating relies on a good knowledge of 14C changes with time. The changes in 14C due to changes in the carbon cycle are therefore minor prior to 1875 and do not affect significantly the millennial scale changes in 14C incorporation into tree rings. The correspondence between major peaks in ice rafted debris in the North Atlantic sediments and major peaks in cosmogenic production of 14C is as strong today as it was in 2001.
The correspondence is particularly strong for the 5-12 kyr BP period when many authors agree that changes in solar activity where a major factor driving climatic changes. The millennial cycle in both climate and solar activity is thus solidly established and supported by the scientific literature. It cannot be waved out by vague unsupported claims that the 14C record is suspect.
It is mildly funny that whenever an argument is being made about solar and climate relationship based on 14C, 10Be will appear in the response. It says a lot about the need to attack the argument through the guilt by association fallacy.
Javier, it can be dismissed by one stadial or interstadial episode that does not line up with your 14C theory. You depend on a single article that has since been called into question.
It took 2 minutes to find an article published 4 years later that found the opposite case for C14.
http://onlinelibrary.wiley.com/doi/10.1002/jqs.927/abstract
You are incorrect Pamela. The link between cold Holocene events and low solar activity is a lot stronger now that it was in 2001. It does not rest on not finding it in the Irish oaks.
————
Solomina, Olga N., et al. “Holocene glacier fluctuations.” Quaternary Science Reviews 111 (2015): 9-34.
http://academiccommons.columbia.edu/download/fedora_content/download/ac:192534/CONTENT/Solomina_et_al.__2015.pdf
Glacier advances clustering at 4.4e4.2 ka, 3.8e3.4 ka, 3.3e2.8 ka, 2.6 ka, 2.3e2.1 ka, 1.5e1.4 ka, 1.2e1.0 ka and 0.7e0.5 ka correspond to general coolings in the North Atlantic. It has been noted that these cooler periods correspond to multidecadal periods of low solar activity at 4.3 ka, 3.8 ka, 3.2 ka, 2.6 ka, 2.3 ka, 1.3 ka, 0.9 ka, 0.7 ka and 0.4 ka>/i>
————
Jiang, Hui, et al. “Solar forcing of Holocene summer sea-surface temperatures in the northern North Atlantic.” Geology 43.3 (2015): 203-206.
https://www.researchgate.net/profile/Jon_Eiriksson/publication/272433842_Solar_forcing_of_Holocene_summer_sea-surface_temperatures_in_the_northern_North_Atlantic/links/54e60bc60cf2cd2e028b8d6a.pdf
Mounting evidence from proxy records suggests that variations in solar activity have played a significant role in triggering past climate changes. … Here we present a high-resolution summer sea-surface temperature (SST) record covering the past 9300 yr … Our results indicate a close link between solar activity and SSTs in the northern North Atlantic during the past 4000 yr
————
Versteegh, Gerard JM. “Solar forcing of climate. 2: Evidence from the past.” Space Science Reviews 120.3-4 (2005): 243-286.
https://www.researchgate.net/profile/Gerard_Versteegh/publication/233400834_Solar_forcing_of_climate_2._Evidence_from_the_past/links/0c96051bebd4077325000000.pdf
At low latitudes, equatorward movement of the ITCZ (upward component of the Hadley cell) occurs upon a decrease in solar activity, explaining humidity changes for (1) Mesoamerica and adjacent North and South American regions and (2) East Africa and the Indian and Chinese Monsoon systems. At middle latitudes equatorward movement of the zonal circulation during solar minima probably (co-)induces wet and cool episodes in Western Europe, and Terra del Fuego as well as humidity changes in Southern Africa, Australia, New Zealand and the Mediterranean. The polar regions seem to expand during solar minima which, at least for the northern hemisphere is evident in southward extension of the Atlantic ice cover.
————
Renssen, H., Goosse, H., and Muscheler, R.: Coupled climate model simulation of Holocene cooling events: oceanic feedback amplifies solar forcing, Clim. Past, 2, 79-90, doi:10.5194/cp-2-79-2006, 2006.
http://www.clim-past.net/2/79/2006/
The coupled global atmosphere-ocean-vegetation model ECBilt-CLIO-VECODE is used to perform transient simulations of the last 9000 years, forced by variations in orbital parameters, atmospheric greenhouse gas concentrations and total solar irradiance (TSI). The objective is to study the impact of decadal-to-centennial scale TSI variations on Holocene climate variability. The simulations show that negative TSI anomalies increase the probability of temporary relocations of the site with deepwater formation in the Nordic Seas, causing an expansion of sea ice that produces additional cooling. The consequence is a characteristic climatic anomaly pattern with cooling over most of the North Atlantic region that is consistent with proxy evidence for Holocene cold phases. Our results thus suggest that the ocean is able to play an important role in amplifying centennial-scale climate variability.
————
You are free to ignore as much solar-climate research as you want, but you shouldn’t go around saying that it cannot be the Sun, because it underscores your ignorance of the issue.
Javier, your first linked reference does not present compelling evidence of solar variation driving glacial episodes.
Your second link uses a questionable C14 reconstruction for solar variation: “Solar activity estimates are based on the reconstructed 14C production rate from the tree-ring based atmospheric 14C calibration record (Musche-ler et al., 2005; Reimer et al., 2009) and the 10Be record from the Green-land Ice Core Project ice core (Vonmoos et al., 2006).”
Your third link is a literature review. Always fraught with biased research selections to prove a point, reviews are not research.
Your final like is a model output using old Solar data.
Try again but this time do your own damn homework.
Pamela,
Why bother?
Nothing I will bring will look compelling to you anyway, yet a series of Irish oaks reflecting local conditions in Northern Ireland is very compelling to you of the opposite. You are strongly biased against the possibility that solar variations can drive significant climate changes. That is a very unscientific posture. Now you are demanding impossible scientific standards from the opposite opinion, while accepting low standards from your own opinion. A clear case of argumentative fallacy.
There are over a hundred papers published every year on the connections between solar variability and climate. That means that there over a thousand scientists that believe that a significant influence of solar variability on climate change is a distinct possibility. Although it is possible that they are all wrong, I do not think you can dismiss the solar variability influence on climate change by waving your arms and demanding impossible proof. There is ample evidence, just not good enough for you, so I don’t see the point in continuing this discussion.
Willis has some interesting ideas about thunderstorms being tremendous convective heat pumps derived from his direct observation of tropical thunderstorms as they happen on a clockwork daily schedule. Add more heat, and the thunderstorm happens a few minutes earlier in the day, lasts a few minutes later into the evening, and in the process pumps more heat higher into the atmosphere with the net result that the average surface temperature remains the same. The storms have a once-a-day frequency, alternating between mostly calm sunny skies followed by the vigorously heat-pumping thunderstorm. Adding more energy to the system subtly changes the length of time the system remains in each state – sunny skies, or thunderstorms – and makes each state a little more vigorous, but the daily frequency remains the same, along with the average temperature.
So turn the Willis thunderstorm model on its side and squint your eyes a little, and we have ENSO. Heat driven convective atmospheric cycles combined with Coriolis forces results in easterlies near the equator that push warm surface waters westward to the Indian ocean. Eventually the winds slacken a little due to a passing cyclone or a butterfly flapping its wings in Texas, and the water comes sloshing back from west to east. We have a giant charge/discharge oscillator that behaves like a spring. I suspect the length of the ENSO cycle is a characteristic of the size of the spring (ocean basin). In any case, if you add more heat to the system, the amount of heat transferred during each cycle will increase, but the 4 to 5 year length of the cycle will still be constrained by the size of the oscillating spring.
Is this what the authors are trying to say? … that over many ENSO cycles the proportion of time spent in the El Nino mode is sometimes greater than the La Nina mode, even though each mode must follow the other on a clockwork time frame? … or that the amount of heat present in the El Nino mode varies over time leading to more prevalent El Nino influenced weather patterns as opposed to El Nina induced weather patterns?
“Willis has some interesting ideas about thunderstorms being tremendous convective heat pumps”
Consider the amount of heat taken in by H2O to make the water in the oceans into water vapor (heat of vaporization X mass) from the Suns energy and then the reverse when that water vapor releases the heat of condensation as required to make vapor back into liquid water. Same is applied to snow when it falls. And there are “rivers” of this water pumping thousands of times the water in the Amazon river moving that heat around the atmosphere.
How is this modeled in the AGW Models?
Does anyone know why the June MEI update hasn’t been released yet ? The May update stated it should be released about June 4.
This article is close to the truth .. but then just misses the point. The El Nino’s don’t amplify natural climate fluctuations … they are the primary cause of the natural climate fluctuations.
The El Nino’s are the sea surface temperature reflection of sub-sea oceanic plate magmatism. The earth has 70,000 km of mid ocean ridges that are the crustal expression of very large and strong magmatism. If this happens in pulses, it has the ability to change the climate of the earth … to end an ice age. What else can cause a 10 degree earth warming in 1 to 2 thousand years ? What we see today is the remanant magmatism of the great pulse that ended the last ice age. And it is visible today as an El Nino. Once those El Nino’s die away, we are going south .. fast.
In the National Geographic’s a few years back (Aug 2010) they had an article on the Blue Holes ( http://ngm.nationalgeographic.com/2010/08/bahamas-caves/todhunter-text) which described the fact that there were repeated increases and decreases in the ocean water level as indicated by the growth patterns of the stalactites and stalagmites. Thus why are they still questioning this?
Stranger yet is that the entire magazine describes how unprecedented global warming was occurring, yet careful reading of the article and the descriptions of the graphics implies that it had happened many times before.
Is the AGW cult brain dead?
So there are other factors which drive temperature changes other than anthropogenic CO2 ? How can this be? There must be some mistake. Surely man and evil capitalism must be behind this El Nino !