Dipole. It’s a word often used among meteorologists and climate scientists. But what does it mean?
In weather terms we can simply think of it as this: one side hot, one side cold. So, as a basic principle, it’s pretty direct. But in a world where extremes between hot and cold are becoming more intense, in North America which has just experienced its most extreme dipole anomaly since record keeping began in 1960, it’s also something that’s important to understand as it relates to ongoing human-caused climate change.
For a recent blockbuster scientific paper by Dr. Simon Wang and associates and published in Geophysical Research Letters has now linked this extreme temperature differential, related polar vortex collapse events, and the California drought with both ongoing physical changes to the Earth System due to human caused climate change and to the first rumblings of a monster El Nino in the Pacific.
Envisioning a Dipole Pushed into An Extreme Form by Climate Change
But to understand how an excessively extreme dipole relates to the historic events of the winter of 2013-2014, it helps to open up one’s imagination. It helps to describe the ground-breaking information provided by Dr. Wang’s new paper in descriptive terms. It helps to, at first, envision a wave. Then to imagine the up-slope of the wave forming a hot, red shape. Now imagine the down-slope forming a cold, blue shape. Now think of this wave growing more intense, extending further in both its up-slope and in its down-slope. Growing hotter on the up-slope side and comparatively colder on the down-slope side.
(GFS Model summary of Polar Vortex Collapse event on January 19, 2014 shows 850 mb temperatures over the Eastern US colder than the same temperatures over parts of Greenland and the Arctic Ocean. 850 mb temperatures over St. Augustine, FL are the same as 850 mb temperatures over central Greenland. Anomalies on the hot side of the dipole in the Arctic hit +40 degrees Fahrenheit in some places. Anomalies on the cold side of the dipole hit more than -35 degrees F in some places. Note the twin, dense high pressure systems sitting sentinel just off the California Coast and deflecting storms north into Alaska. Image source: NOAA/GFS.)
Having established the wave form and related temperature extremes, lay the shape over North America and adjacent Pacific Ocean. The up-slope covers the Eastern Pacific, Alaska, a section of the Beaufort Sea in the Arctic, Western Canada and the Western US. The down-slope swings from the eastern side of the Beaufort, on in through Central and Eastern Canada and bisects the US diagonally from the Dakotas to the Gulf Coast east of Texas.
Now let’s envision this wave as a flow of upper level air called the Jet Stream and let’s think about the various atmospheric aspects that feed it. Looking west, we happen upon a very warm pool of water in the Western Pacific east of the Philippines. This warm pool is the source of an El Nino that will likely occur within one years time. A heat pocket given added intensity by both rising atmospheric temperatures and strong winds transferring that added energy into the vast Pacific Ocean. The heat waits, wanting to spread out across the Pacific surface in an energetic return to the air. But, for now, it simmers in its deep pool, providing energy for the powerful dipole we’ve just described.
The heat from this warm pool radiates into the atmosphere creating lift. Further north, a cold pocket is driven south by another strong atmospheric wave pattern over the Asian continent. The cold air pocket runs south over Japan. The hot and the cold difference generates a very strong upper level synoptic (horizontal form weather patterns stretching more than 1,000 kilometers) wind pattern that stretches all the way across the Pacific Ocean.
The winds run southwest to northeast until they encounter the hot bulge of our already described dipole over the Eastern Pacific near the US west coast and Canada. This warm current turned the already rapid winds due north where they rushed up over Alaska and into a sea ice pack far weaker than in decades past. A sea ice sheet gradually thinning, breaking up, and venting heat from a warming Arctic Ocean below. And so these, already strong, winds were not turned back by the now much weaker cold until they had driven far, far into the Arctic Ocean (and it is here that we must give a hat tip to Dr. Jennifer Francis, who finds her predictions regarding sea ice loss and high amplitude Jet Stream waves again validated).
(Upper level wind pattern on January 23, 2014 shows a polar vortex that has essentially been ripped in half by the warm side of the west coast dipole and the high amplitude Jet Stream wave forming over top of it. Image source: University of Washington.)
Now imagine a strong dome of high pressure forming in the wake of this powerful and ongoing wind flow, sheltered and growing ever stronger on the hot side of the dipole. Imagine it blocking the path of storms, even as it concentrated heat and warmth. Imagine California receiving 1/4 or less of its typical winter rainfall as a result. A most recent and extreme insult to years of drought forcing authorities to ration water in many places.
Now return to that strong wind finally being turned south somewhere in the far, far north, in the Beaufort Sea just south of the North Pole. Then imagine these now cold-laden winds rushing south. Running over Hudson Bay and eastern Canada. Roaring over the Great Lakes and carrying with them a cyclone of cold Arctic air that should have remained in the far north. The polar vortex that should have stayed over places like Svalbard but instead collapsed under the warm wind flow and shifted far south to places like Toronto or Chicago or Detroit or Washington DC.
Now at last imagine another synoptic pattern as the Arctic air of the polar vortex encounters the warmth of the Gulf Stream. This pattern is laden with powerful storms that bomb out over the UK again and again, resulting in the stormiest winter for that island nation in over 200 years.
And here we have the dipole of the winter of 2013 and 2014. A west coast that was hot, hotter than usual all the way from California to the far north of Alaska and an East Coast that from Canada to the Gulf Coast became the repository for cold, cold Arctic air that was shoved south as the polar vortex collapsed down the steep face of the one of the largest and longest lasting Jet Stream waves on record.
(Dr. Francis explains how polar amplification results in higher amplitude Jet Stream wave patterns.)
Dipole. One side hot. One side cold. But, in this case, in the case of the winter of 2013-2014, it’s a historic and anomalous dipole. A freak born of the climate change we’ve caused mixing up with the Pacific Ocean heat of a rising El Nino. A record hot, dry winter for the US West that ignites wildfires in winter and forces the government to ration California water resources. A severe dry spell that closes farms and drives US food prices up by 15%. A record cold, stormy winter in the Eastern US and a series of super-intense storms screaming across the North Atlantic to submerge Somerset and rip massive chunks out of a rocky UK coastline.
This clear picture of a climate-change caused event was this week provided through the groundbreaking new research by Dr. Wang and fellows. These top scientists engaged climate models and analyzed past records to find the culprits of the weather extremes we witnessed during this past winter. And what they found was a very high correlation in the models with the extreme dipole over North America and the Arctic, an oncoming El Nino, and climate change driven impacts.
For not only was this year’s dipole the most extreme on record, it was also likely made far more extreme by an emerging Monster El Nino acting in concert with severe global-warming related reductions in Arctic sea ice cover, increases in Pacific Ocean heat and atmospheric moisture content, and related changes to the upper level air flows of the Northern Hemisphere polar Jet Stream.
Links:
Read Further Excellent Reporting on the Wang Report Here:
California Drought/Polar Vortex Jet Stream Pattern Linked to Global Warming
Bombshell Study Ties Epic California Drought ‘Frigid East’ To Manmade Climate Change
Large and Growing List of Scientific Studies Linking Human Climate Change to Current Weather Extremes (hat tip to Weather Underground)
Changing the Face of Mother Nature
The Seasonal Atmospheric Response to Projected Sea Ice Loss in the Late 21rst Century
Evidence Linking Arctic Amplification to Extreme Weather in the Mid Latitudes
Influence of Low Arctic Sea Ice Minima on Anomalously Cold Eurasian Winters
Impact of Sea Ice Cover Changes on the Northern Hemisphere Winter Circulation
Impact of Declining Arctic Sea Ice on Winter Snowfall
Large Scale Atmospheric Circulation Changes Associated with the Recent Loss of Arctic Sea Ice
A Link Between Reduced Kara-Barents Sea Ice and Cold Winter Extremes Over Northern Continents
Northern Hemisphere Winter Snow Anomalies
Impact of Projected Future Sea Ice Reduction on Extratropical Storminess and the NAO
Cold Winter Extremes in Northern Continents Linked to Arctic Sea Ice Loss
Precipitation Shifts Over Western North America as a Result of Declining Sea Ice Cover
Disappearing Arctic Sea Ice Reduces Available Water in the American West
Potential Impacts of the Arctic on Interannual and Interdecadal Summer Precipitation in China
Influence of Arctic Sea Ice on European Summer Precipitation
On the Relationship Between Winter Sea Ice and Summer Atmospheric Circulation over Eurasia
(Partial list, view the rest here)
robertscribbler 
Miep
/ April 17, 2014Colorado Bob, thanks for all your links, which I regularly steal and use elsewhere, with an occasional hat tip to you. Here’s one back for you (and anyone else) interesting piece on water usage in Clark County (Las Vegas). Quite well done, I thought.
http://vegasseven.com/2014/04/16/get-damn-shower/
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ravinathan
/ April 17, 2014Excellent summation. Extending the story forward, the likely record El Niño will release its heat into the atmosphere with all of the resulting impacts in floods and droughts but what of the following winter(s) if one cares to speculate? The warm pacific pool would have depleted its heat content but the elongated jet stream will likely continue as the arctic melt continues..
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robertscribbler
/ April 17, 2014That’s a good question! To determine that, we’d probably want to compare a typical post El Niño year with ongoing and known trends due to climate change. For some corollary, we could look at 1999 as well as 2008 and 2011.
Generally, you would see natural variability push for a year about .02 to .05 C cooler than the peak El Niño year and you would perhaps see some pseudo recovery in various areas.
For the US Southwest the rains of El Niño fade and it’s back to the long, climate change induced drying trend. I think it likely that the dipole and high amplitude Rossby Waves re-assert rather strongly in some variant with sections of the continents and Greenland taking a disproportionate chunk of the remnant cold as the Arctic Ocean is now rather warmer and unable to sink cold during winter time.
The other point to consider would be what irreversible tipping points are crossed during a strong El Niño year? Have we started a trend of record fires in the Amazon, for example? And what happens if there is major physical change due to droughts, floods and fires during the El Niño year as this will have knock-on effects for the years following.
Last of all, I think we need to consider the possible impacts of a PDO switch. If that occurs, El Niño and not La Niña will be the prominent trend. If that happens, the ocean influences will be somewhat different than what we’ve seen during the past 14 years.
Since the question has been asked, I’ll start digging a bit in the meta analysis to see what we can come up with. Thanks for the thought!
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Mark from New England
/ April 17, 2014A great article that I understand after our conversations in the previous article.
You wrote: “Since the question has been asked, I’ll start digging a bit in the meta analysis to see what we can come up with. Thanks for the thought!”
Which is why I appreciate your efforts here so much. Not only do you keep us updated on climate change in real time, but you are able to look beyond the cutting edge even and give us a heads up as to what could be coming in the next few years.
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robertscribbler
/ April 17, 2014Given your questions in the previous article, Mark, I thought such a post might be appropriate. The issue of sea ice can wait a bit, so I put it on the back burner to highlight the excellent new Wang study and to, hopefully, provide a good, and somewhat easy to understand, description of events. Not sure if this is my best post. But my brain is fried and I’m not the best at self-editing.
Will keep looking past that cutting edge, though!
As an aside, I am somewhat heartened by the pace of adoption for renewables. New post over at Climate Crocks shows Austin will get 1/3 of energy from renewables soon. Figures I’m looking at show 43% of all new energy for generation worldwide is from renewables. This is a good start. But the point we need to be pushing for is 100% new renewables with net negative fossil fuel use and adoption. Even then, we will need radical changes to agriculture (far less ruminants and meat in general), an abolishment of slash and burn land use, and biomass plants equipped with carbon capture to begin bringing down global atmospheric ghg loading.
We have a huge number of doomers in our audience, but I think I’m going to cut against trend and write an ‘Is Civilization Redeemable?’ piece at some point. Footprints of El Nino for today probably. There’s just so much to cover!
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Mark from New England
/ April 17, 2014Robert,
You wrote – “Figures I’m looking at show 43% of all new energy for generation worldwide is from renewables”. That is encouraging. Is that 43% of new mega-wattage or 43% of the number of projects? I hope the former.
I’m in between the ‘there may still be hope’ and ‘Doomer’ points of view – and have thought for a long time (just an intuition) that humanity will wake up in time to barely avert the very worst scenario of, say, setting off a Permian level extinction and hence our own within a hundred years plus. Still, I think it’s going to be bad, as we’re locked into 2 – 3 degrees C at the very least. Hopefully that much of an increase won’t set up an uncontrollable release of methane. Paul Lynas in his book “Six Degrees” (perhaps now dated) states that any increase over 2 C could set off the dominoes of self-reinforcing feedbacks all the way up to 6C, even if new human GHG emissions are brought close to zero. One hopes he is wrong! I know you have a somewhat more nuanced view of the near-term methane feedbacks than the Arctic Methane Emergency Group.
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robertscribbler
/ April 17, 201443% of all new projects on the basis of productive capacity installed. Globally, 2013 saw 8.5% of all electrical energy generation come from wind and solar. We have entire countries running on 50% plus renewable output. A good start, but not enough in itself, by itself. And climate change is a dire threat now. So the pace of change needs to radically sharpen.
Lynas implies that a 2 C ECS equals an ESS of 6 C. This is perhaps possible due to the velocity of current human-based change. But, in my view, the best analysis of paleoclimate indicates that a 2 C ECS comes out to an ESS of 4 C. It’s all still pretty terrible but if you are at zero emissions once you hit 2 C, it takes a long time to get to 4 C from all the ESS feedbacks, probably about two centuries or so. If at that point, you have some kind of net negative carbon regime in place (atmospheric capture etc), then you can prevent the more dire warming to 4C and possibly only reach a total of 3 or perhaps 2.5 at peak.
Now, as a caveat, it’s possible that the Earth System is much more sensitive to a rapid warming to 2 C and will trip over major feedbacks all the way to 6 C pretty fast (2100 to 2150). In such a situation human civilization is in for a severe beating and the world will probably see a rather severe mass extinction. The key here is how fast the permafrost thaws and releases carbon, how much peat is converted to carbon by fires (human or wildfires) worldwide, and how sensitive those sea-bed methane stores are to our current high velocity warming. My view on this sensitivity is probably closer to that of paleoclimate (2 C ECS equals 4 C ESS) but I believe that it would be foolish not to keep a weather eye to worse impacts (hence the ongoing analysis and not completely discounting the worst cases indicated by AMEG and others on the high sensitivity side).
That’s the glimmer of a best case scenario if we really move. I’d say we’re not quite really moving now. Instead, we are in conflict between fossil fuel and business interests and those who push for sustainability. Sustainability seems to continue to make gains against a tide of opposition. But in this backdrop emissions continue to grow and the big polluters still hold on.
So a sliver of hope in an otherwise dire picture. But the take away here is that there is a path to survival if we decide to take it.
I suppose the analogy is that you go to the doctor and the doctor tells you that if you don’t stop drinking alcohol, then in a few years your liver will fail and you’ll probably die. If you do, you’ll suffer from reduced liver function for the rest of your life and feel the pangs of it indefinitely, but you’ll probably survive the ordeal and even end up being more healthy than you are now if you take on this recommended regime of exercise and diet (sustainability/carbon capture). But the deal here is that you pretty much have to manage to kick your alcoholic habit completely over the course of the next year and take on the new diet and exercise regime immediately. Otherwise, the damage is permanent and will take you down.
Now the doctor is pretty qualified and he may be right. But there’s a chance (15% or so) that even if you do everything you can, you might not make it. What’s guaranteed is that if you do nothing, the very bad condition settles in and probably takes you down (95% plus).
We have a number of cheer leaders for civilization destruction. I don’t find this to be very helpful or healthy. I guess my view is more nuanced than theirs as well. I see humans not as angels or demons, but as another kind of animal. We have acted as predators for quite some time. But the world can no longer support us if we continue to behave in this manner. As perhaps the most adaptable species, we have the option to alter behavior and life-styles to a non-predatory mode and act more in partnership with each other and other life. If we do not. We probably don’t survive because the Earth System can’t/won’t support us. So in my view, it’s not civilization that is the problem, for us and so many other species, but how that civilization manifests. Empire/exploitative systems fail, cooperative non exploitative systems succeed long term in the context of human sustainability.
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james cole
/ April 17, 2014Looks like methane is going to become more and more important to global climate change, and this study below is more evidence. “The Environmental Protection Agency is under fire for underestimating the amount of methane gas emitted during natural gas operations, including fracking, thanks to a new study published in the Proceedings of the National Academy of Sciences (PNAS).
The study has 13 co-authors from several academic and research institutions, and used an aircraft to identify large sources of methane and quantify emission rates in southwestern Pennsylvania in June 2012. The authors discovered that emissions rates per second were 1,000 times higher than those estimated by the EPA for the same time period.
“Methane is the second most prevalent greenhouse gas emitted in the United States from human activities,” the EPA website states. Carbon dioxide is the most prevalent, but it is not as damaging of a greenhouse gas as methane. “Pound for pound, the comparative impact of (methane) on climate change is over 20 times greater than (carbon dioxide) over a 100-year period.”
The goal of the study was to try to understand if the measurements of airborne methane differed from the measurements taken at ground level, the Los Angeles Times reported. “Researchers flew their plane about a kilometer above a 2,800 square kilometer area in southwestern Pennsylvania that included several active natural gas wells. Over a two-day period in June 2012, they detected 2 grams to 14 grams of methane per second per square kilometer over the entire area. The EPA’s estimate for the area is 2.3 grams to 4.6 grams of methane per second per square kilometer.”
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robertscribbler
/ April 17, 2014I’ve seen this one. Fracking releases far more methane than previously estimated. One of the reasons why the practice should be halted in favor of rapid transition to renewables.
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Mark from New England
/ April 17, 2014In something totally unrelated: It’s good to know that if humans wreck the biosphere here, there are likely many planets with life out there, like the recently announced Kepler 186-f. It’s only 500 light years away.
Robert, you have a flying disc with interstellar capabilities, right? How many passengers can you take? 🙂
http://www.bbc.com/news/science-environment-27054366
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robertscribbler
/ April 17, 2014I’m putting in my last, best effort before my buddies over on K 186-f to get me off this smoldering rock. I’ll ask them if they can spare a seat for you 😉
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Colorado Bob
/ April 18, 2014In California’s Sierra Nevada Mountains, where runoff from the spring snowpack provides much-needed water supplies during the dry season, half of the snowpack’s liquid water equivalent melted in just the past week in some areas, due to temperatures that soared as high as 12 degrees Fahrenheit above average of early April, according to the U.S. Drought Monitor.
To make matters worse, the sudden snow melt in California barely boosted reservoir supplies, which remain well below average across the state.
http://mashable.com/2014/04/17/california-snowpack-melt-drought/
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Colorado Bob
/ April 18, 2014RS –
Excellent post. on a very complex topic.
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