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Thursday, May 30, 2013

Fracking "Shock Doctrine" Unveiled as 2013 Illinois Legislative Session Nears End: Illinois state legislator may be influenced by campaign contributions from fracking interests while pushing through a bad regulatory bill

Fracking "Shock Doctrine" Unveiled as 2013 Illinois Legislative Session Nears End

by Steve Horn, DeSmogBlog, May 30, 2013

[Note to readers:  I tracked campaign contributions (probably a good $160,000) to a downstate local state congresscritter, the reg bill's chief sponsor, John Bradley, which can be found here:  ]

The shale gas industry has performed the "shock doctrine" at the 11th hour of the 2013 Illinois State Legislature's debate over hydraulic fracturing ("fracking"), the toxic horizontal drilling process through which oil and gas is obtained from shale rock basins nationwide. 
This year, both the Illinois House and Senate are set to adjourn for the year on May 31, and HB 2615 -- the Hydraulic Fracturing Regulation Act -- will likely receive a full floor vote by adjournment. The regulatory bill has 59 House co-sponsors and eight Senate co-sponsors. Democratic Party Gov. Pat Quinn said he will sign the bill when it arrives on his desk. 

With the deadline looming rapidly, anti-fracking activists -- or "fracktivists" -- have been protestingsitting intestifying in committee hearings and committing acts of non-violent civil disobedience daily at the Illinois State Capitol in Springfield. 
Two days before that deadline, the Associated Press (AP) reported that records from the state Department of Natural Resources (DNR) indicate fracking already has begun in Illinois' New Albany Shale Basin
"Carmi, Ill.-based Campbell Energy LLC submitted a well-completion report last year to the [DNR] voluntarily disclosing that it used 640,000 gallons of water [fracking] a well in White County," AP reports. AP also explained the report was first obtained by the Natural Resources Defense Council (NRDC).  
The last-minute announcement paves the way for a "buzzer beater" public relations effort by the industry to ram through a regulatory bill deemed the "most comprehensive fracking legislation in the nation" by its proponents and a "worst case scenario" by its detractors. The bill was predominantly written by Illinois Oil and Gas Association (IOGA), working alongside two major environmental groups: the Illinois Sierra Club and NRDC. 
NRDC told DeSmogBlog it caught wind of the Campbell Energy well-completion reportnot from the industry itself at the negotiating table, but through a Freedom of Information Act (FOIA) request. The FOIA request also showed another company has fracked a well: Strata-X Energy Ltd.
Among other things, the bill allows fracking to take place within 1,500 feet of groundwater sources and 500 feet of schools, houses, hospitals, nursing homes, and places of worship; and within 300 feet of rivers, lakes, ponds and reservoirs. Necessary context: the horizontal drilling portion of the fracking process extends between 5,000-7,500 feet.
"We need to acknowledge that fracking is legal today in Illinois, and for all we know, may already be occurring as you read this,Sierra Club Illinois' Director Jack Darin wrote ambiguously in a February 2013 Huffington Post piece. 
Darin's ominous hypothetical scenario proved true, begging the question: did the industry hide this from those it was at the negotiating table with until the last minute? Darin could not be reached for comment at the time this article went to press. 

Fracking Well Owned by IOGA Board Member, Connected to Lake Michigan Oil Drilling

Campbell Energy LLC's co-founder Jakob Campbell is on the Board of Directors of IOGAIn other words, IOGA -- the industry lobbying force that is pushing for and helped write the Illinois fracking regulatory bill -- has a Board Member using the well-completion report as a trojan horse, of sorts. 
Ann Alexander, Senior Attorney in NRDC's Chicago Office, former Environmental Counsel to Illinois Attorney General Lisa Madigan, and one of the environmental representatives at the negotiating table for the regulatory bill told DeSmogBlog that industry representatives at the table included someone from a California fracking company, an Illinois fracking company, IOGA VP Brad Richards, and a representative from the IL Chamber of Commerce. 
Ann Alexander, NRDC Senior Attorney (Photo Credit: NRDC Switchboard)
"These are not people who would necessarily know what Campbell was doing. I have absolutely no reason to believe IOGA knew about it and I honestly doubt that they did," she said. "I look at it and say 'How would they know?' I mean, this was a slip of paper they submitted to DNR. Maybe IOGA has some data and they are tracking it like that. If they are, I have never heard about it and I have no reason to believe they have it." 
Alexander later joked that IOGA may have conned those at the negotiating table about Campbell, though she didn't think that was the case. 
"They certainly did a good imitation for people who apparently had no idea, and I say that jokingly because I honestly don't think anybody in that room knew what was going on when we first started the conversation," she continued. "I mean, IOGA is there to promote its interests, but I have no reason to believe IOGA is collecting this data -- this voluntary data -- that some companies are submitting to DNR. There is no reason why the industry would have wanted to hide the ball on this."
Could IOGA's VP really not have known that one of his own Board members had performed a well completion? Seems highly unlikely and more along the lines of an imitation of ignorance.  
IOGA's sleight of hand enables proponents of the weak legislation to argue that, because fracking is already happening, the public should accept drilling with essentially toothless regulations -- which will be difficult to enforce given a seriously understaffed and under-funded DNR -- or get continued drilling with absolutely no regulations. There is no third option, according to this odd narrative. 
An alternative path does exist, though, in the form of a moratorium bill. That bill has galvanized the support of grassroots activist groups22 House co-sponsors and nine Senate co-sponsors
Campbell also co-founded Camata Energy LLC with Florencio Mata. Mata was the vice president of exploration of Federated Natural Resources when it was running geological and seismic tests to do offshore drilling in Lake Michigan in the mid-1980s.
Offshore drilling in Lake Michigan has been a point of contention for decades and a moratorium is still on the books.
"Activists and a growing band of politicians are alarmed by the specter of surface leaks from wellheads that could taint drinking water, harm public health and affect wildlife," explained a 2001 article published in The Detroit News about prospective drilling in Lake Michigan, a description that today rings equally true for fracking. 
U.S. Sen. Ron Johnson (R-WI) supports drilling in Lake Michigan, as do numerous other public officials.
U.S. Sen. Ron Johnson (R-WI) (Photo Credit: Wikimedia Commons
"The bottom line is we are an oil-based economy," he said in 2010 when asked about drilling in the Great Lakes. "There's nothing we're gonna do to get off of that for many, many years. I think we have to be realistic and recognize that fact and, you know, I, I think we have to, get the oil where it is, but we have to do it where it is."

Illinois Fracktivists React

Grassroots activists in Illinois interviewed by DeSmogBlog find the revelation about the well-completion report unsavory and the timing of it suspect. 
"The timing of the announcement of the well-completion report is awfully suspicious," remarked Tabitha Tripp, a concerned citizen from Southern Illinois. "A moratorium is needed to halt permits, study the science, look at the health care studies before we have a disaster we can't clean up.
Sit-in outside of Gov. Pat Quinn's Office (Photo Credit: Just Blono)
Don Carlson, Executive Director of Illinois People's Action, put it more bluntly. 
"With the apparent relationship between the board member of the IOGA being the same company engaged in the fracking well-completion, the oil and gas industry has manufactured a policy-making crisis they not only have the solution to, but from which they'll profit greatly," Carlson told DeSmogBlog"This brazen manipulation of environmental policy-making should make legislators as angry as it makes grassroots citizens. Bullies who throw rocks should not be rewarded with window insurance.

Van Jones: The Obama Keystone Pipeline?

We have been hearing a lot about scandals recently.
But if President Obama approves a pipeline equal to more than seven new coal-fired power plants? And does so just months after promising to act AGAINST climate change?
Now THAT'S a scandal.
President Obama said in his second inaugural address that failing to act on climate change would "betray future generations." Now, it looks like he will do exactly that by approving the Keystone XL pipeline.
I made a new video about what is at stake, please take a look:
(I'd appreciate any help getting this out there! Please share this video on Facebook or on Twitter. Thank you!!)
If President Obama truly thinks this project is good for America, he should embrace it publicly. He should call it the "Obama Tar Sands Pipeline." He should show up at the ribbon cutting. If he refuses to do that and still approves Keystone XL, the first thing that pipeline will run over is his credibility on climate.

Monday, May 27, 2013

EPA raises allowable limit of glyphosate from terracist Monsanto's RoundUp pesticide, destroys human microbiome

Gut punch: Monsanto could be destroying your microbiome

First the bad news: The“safest” herbicide in the history of science may be harming us in ways we’re just beginning to understand. And now for the really bad news: Because too much is never enough, the Environmental Protection Agency just raised the allowable limits for how much of that chemical can remain on the food we eat, and the crops we feed to animals — many of which end up on our plates as well. If you haven’t guessed its identity yet, it’s Monsanto’s Roundup, a powerful weed killer.
The EPA and Monsanto are apparently hoping that no one notices the recent rule change — or, if we do notice, that we respond with a collective shrug. But that, my friends, would be a mistake. While Roundup may truly be the “safest” pesticide ever invented, that isn’t quite the same as “safe.” It just may be that Roundup represents a hitherto unrecognized threat to our health — not because of what it does to our bodies, but because of what it does to our “internal ecology,” a.k.a. our “microbiome.”
As Michael Pollan deftly cataloged in his must-read cover story in the most recent New York Times magazine, scientists are just beginning to explore the inner reaches of our bodies to understand how our microbiome affects our health. Nonetheless, there are some growing signs that Roundup might be the last thing you want in there.
Monsanto would, of course, disagree. The common claim is that Roundup’s active ingredient, glyphosate, is less toxic than aspirin. How can one of the most effective broad-spectrum herbicides in the history of humankind be less toxic than aspirin?
I’m glad you asked. For two reasons. First, because glyphosate isn’t well absorbed by our digestive tract: 98% of it passes right through us. And second, because its “mode of action” involves a biochemical process that is specific to plants. (For the budding chemists among you, it disrupts the metabolic process known as “the shikimate pathway,” which humans do not have.)
Now, the actual safety and environmental effects of Roundup are the subject of some dispute. It gets into waterways and may affect aquatic plants. New research has implicated it in the catastrophic loss of amphibians. Even the U.S. Department of Agriculture has evidence, which it downplays, that Roundup may damage soil through its impact on beneficial soil microbes and interfere with the growth of plants, including Roundup Ready varieties that have been genetically engineered to resist the herbicide. And there’s the controversial claim by a Purdue University plant pathologist that Roundup has caused an increase in miscarriage and infertility in livestock.
There are studies that show glyphosate is toxic to human placental cells, but you’re unlikely to run into high enough concentrations to show those effects — unless you’re a farmworker. A study of Berlin residents [PDF], meanwhile, found glyphosate levels in human urine that exceeded Germany’s safe drinking water limits [PDF].
While it’s true that glyphosate the chemical has been the subject of much scientific analysis, it’s also true that farmers don’t use pure glyphosate. They use Roundup on their fields — and Roundup is a product with other “inactive” chemical ingredients. And there is increasing evidence that Roundup as a product is far more toxic than glyphosate on its own because the ingredients interact in troubling ways.
All of which is to say that there’s isn’t really a good health argument in favor of increasing Americans’ exposure to the chemical. There are, however, some pretty compelling reasons not to — and that’s where your microbiome comes into the picture. Even if we aren’t absorbing all the Roundup that’s on the food we eat, we are certainly exposing the residents of our digestive tract to it. And here’s the funny thing. While we don’t have the metabolic process that Roundup disrupts, many microbes do.
So, in short, we may be dousing our interior landscapes with a potent and effective intestinal flora herbicide. Oopsie.
Researchers are only now beginning to explore this idea. There is new research out of Germany that establishes that glyphosate kills many species of beneficial animal gut bacteria while not affecting more harmful gut bacteria, like E. coli and the bacteria that causes botulism, which is apparently at epidemic levels in cattle. And it’s not a stretch to say that it likely has a similar effect on the versions of those bacteria that have colonized us.
And, as Pollan explains, our gut bacteria play a core role in maintaining our health, although in ways that are not at all understood. The research is in its earliest days, but it’s possible that an unhealthy microbiome could contribute to obesity and other diseases, especially those caused by inflammation.
It’s all very speculative, but you can see where this is leading. While we’re just beginning to understand how our microbiome works and how it may prove essential to preventing all sorts of diseases, our governments are increasing the amounts of this anti-microbial herbicide Big Ag is allowed to leave on our food.
This is all happening at a time when we have almost no data on how much we’re exposed to this chemical in the first place. One reason that glyphosate has continued to fly under the mainstream toxic chemical radar is that it’s actually very difficult to test for. There are only a handful of labs that can do it and it’s an expensive process. In fact, the USDA’s pesticide monitoring program only tests a single crop, soybeans, for glyphosate residue. This is true even though it’s used on a huge variety of crops, both directly on the plants, in the case of Roundup Ready, and indirectly, through spraying on fields before planting non-resistant crops.
So why would the EPA allow more of this stuff in our food? The agency didn’t decide to do this entirely on its own, of course. It did so because Monsanto asked.
Here’s the thing: As farmers adopted Monsanto’s genetically modified seeds in droves — the majority of corn, soy, and cotton grown worldwide includes the company’s Roundup Ready trait — there has been an explosion in the use of the pesticide for which the trait is designed: You guessed it, Roundup.
In the U.S. alone, it’s estimated that over 200 million pounds of the stuff are spread on fields and farms every year. That’s almost triple the amount used in 2001. (These numbers, by the way, are all estimates, since the USDA doesn’t precisely track glyphosate use because MONSANTO!)
There’s clearly more and more Roundup getting on our food. What else is Monsanto to do but get governments to bless this development? Both the E.U. and the U.S. have now complied. Stateside, the EPA has approved a significant increase on various grains, fruits, and vegetables, and upped the allowable limit on animal feed by a factor of 100.
Does that sound like a recipe for disaster to you? It probably should. It should also sound like yet another reason to buy organic food and either organic or pastured dairy and meat.
If it feels like Monsanto and its biotech brethren get to call the shots when it comes to toxic chemicals on our food, well, you’re right. On the other hand, the EPA is still accepting comments on these new glyphosate limits. Maybe if consumers make enough noise, the agency might reconsider.
Tom Laskawy is a founder and executive director of the Food & Environment Reporting Network and a contributing writer at Grist covering food and agricultural policy. His writing has also appeared in The American ProspectSlateThe New York Times, and The New Republic. Follow him on Twitter.

Sunday, May 26, 2013

Terracide and the Terrarists: The Biggest Criminal Enterprise in History Is Destroying the Planet for Record Profits

by Tom Engelhardt, Tom Dispatch, May 23, 2013

We have a word for the conscious slaughter of a racial or ethnic group: genocide.  And one for the conscious destruction of aspects of the environment: ecocide.  But we don’t have a word for the conscious act of destroying the planet we live on, the world as humanity had known it until, historically speaking, late last night.  A possibility might be “terracide” from the Latin word for earth.  It has the right ring, given its similarity to the commonplace danger word of our era: terrorist.

The truth is, whatever we call them, it’s time to talk bluntly about the terrarists of our world.  Yes, I know, 9/11 was horrific.  Almost 3,000 dead, massive towers down, apocalyptic scenes.  And yes, when it comes to terror attacks, the Boston Marathon bombings weren’t pretty either.  But in both cases, those who committed the acts paid for or will pay for their crimes.

In the case of the terrarists -- and here I’m referring in particular to the men who run what may be the most profitable corporations on the planet, giant energy companies  like ExxonMobilChevronConocoPhillipsBP, and Shell -- you’re the one who’s going to pay, especially your children and grandchildren. You can take one thing for granted: not a single terrarist will ever go to jail, and yet they certainly knew what they were doing.

Call it irony, if you will, or call it a nightmare, but Big Oil evidently has no qualms about making its next set of profits directly off melting the planet.

It wasn’t that complicated. In recent years, the companies they run have been extracting fossil fuels from the Earth in ever more frenetic and ingenious ways. The burning of those fossil fuels, in turn, has put record amounts of carbon dioxide (CO2) into the atmosphere. Only this month, the CO2 level reached 400 parts per million for the first time in human history. A consensus of scientists has long concluded that the process was warming the world and that, if the average planetary temperature rose more than two degrees Celsius, all sorts of dangers could ensue, including seas rising high enough to inundate coastal cities, increasingly intense heat waves, droughts, floods, ever more extreme storm systems, and so on.

How to Make Staggering Amounts of Money and Do In the Planet

None of this was exactly a mystery. It’s in the scientific literature. NASA scientist James Hansen first publicized the reality of global warming to Congress in 1988. It took a while -- thanks in part to the terrarists -- but the news of what was happening increasingly made it into the mainstream. Anybody could learn about it.

Those who run the giant energy corporations knew perfectly well what was going on and could, of course, have read about it in the papers like the rest of us. And what did they do? They put their money into funding think tanks, politicians, foundations, and activists intent on emphasizing “doubts” about the science (since it couldn’t actually be refuted); they and their allies energetically promoted what came to be known as climate denialism. Then they sent their agents and lobbyists and money into the political system to ensure that their plundering ways would not be interfered with. And in the meantime, they redoubled their efforts to get ever tougher and sometimes “dirtier” energy out of the ground in ever tougher and dirtier ways.

The peak oil people hadn’t been wrong when they suggested years ago that we would soon hit a limit in oil production from which decline would follow.  The problem was that they were focused on traditional or “conventional” liquid oil reserves obtained from large reservoirs in easy-to-reach locations on land or near to shore.  Since then, the big energy companies have invested a remarkable amount of time, money, and (if I can use that word) energy in the development of techniques that would allow them to recover previously unrecoverable reserves (sometimes by processes that themselves burn striking amounts of fossil fuels): fracking, deep-water drilling, and tar-sands production, among others.

They also began to go after huge deposits of what energy expert Michael Klare calls “extreme” or “tough” energy -- oil and natural gas that can only be acquired through the application of extreme force or that requires extensive chemical treatment to be usable as a fuel.  In many cases, moreover, the supplies being acquired like heavy oil and tar sands are more carbon-rich than other fuels and emit more greenhouse gases when consumed.  These companies have even begun using climate change itself -- in the form of a melting Arctic -- to exploit enormous and previously unreachable energy supplies.  With the imprimatur of the Obama administration, Royal Dutch Shell, for example, has been preparing to test out possible drilling techniques in the treacherous waters off Alaska. 

Call it irony, if you will, or call it a nightmare, but Big Oil evidently has no qualms about making its next set of profits directly off melting the planet.  Its top executives continue to plan their futures (and so ours), knowing that their extremely profitable acts are destroying the very habitat, the very temperature range that for so long made life comfortable for humanity.

Their prior knowledge of the damage they are doing is what should make this a criminal activity.  And there are corporate precedents for this, even if on a smaller scale.  The lead industry, the asbestos industry, and the tobacco companies all knew the dangers of their products, made efforts to suppress the information or instill doubt about it even as they promoted the glories of what they made, and went right on producing and selling while others suffered and died.

And here’s another similarity: with all three industries, the negative results conveniently arrived years, sometimes decades, after exposure and so were hard to connect to it.  Each of these industries knew that the relationship existed.  Each used that time-disconnect as protection.  One difference: if you were a tobacco, lead, or asbestos exec, you might be able to ensure that your children and grandchildren weren’t exposed to your product.  In the long run, that’s not a choice when it comes to fossil fuels and CO2, as we all live on the same planet (though it's also true that the well-off in the temperate zones are unlikely to be the first to suffer).

If Osama bin Laden’s 9/11 plane hijackings or the Tsarnaev brothers’ homemade bombs constitute terror attacks, why shouldn’t what the energy companies are doing fall into a similar category (even if on a scale that leaves those events in the dust)?  And if so, then where is the national security state when we really need it? Shouldn’t its job be to safeguard us from terrarists and terracide as well as terrorists and their destructive plots?

The Alternatives That Weren’t

It didn’t have to be this way.

On July 15, 1979, at a time when gas lines, sometimes blocks long, were a disturbing fixture of American life, President Jimmy Carter spoke directly to the American people on television for 32 minutes, calling for a concerted effort to end the country’s oil dependence on the Middle East.  “To give us energy security,” he announced,
“I am asking for the most massive peacetime commitment of funds and resources in our nation's history to develop America's own alternative sources of fuel -- from coal, from oil shale, from plant products for gasohol, from unconventional gas, from the sun... Just as a similar synthetic rubber corporation helped us win World War II, so will we mobilize American determination and ability to win the energy war.  Moreover, I will soon submit legislation to Congress calling for the creation of this nation's first solar bank, which will help us achieve the crucial goal of 20% of our energy coming from solar power by the year 2000.”
It’s true that, at a time when the science of climate change was in its infancy, Carter wouldn’t have known about the possibility of an overheating world, and his vision of “alternative energy” wasn’t exactly a fossil-fuel-free one.  Even then, shades of today or possibly tomorrow, he was talking about having “more oil in our shale alone than several Saudi Arabias.”  Still, it was a remarkably forward-looking speech. 

Had we invested massively in alternative energy R&D back then, who knows where we might be today?  Instead, the media dubbed it the “malaise speech,” though the president never actually used that word, speaking instead of an American “crisis of confidence.”  While the initial public reaction seemed positive, it didn’t last long.  In the end, the president's energy proposals were essentially laughed out of the room and ignored for decades.

As a symbolic gesture, Carter had 32 solar panels installed on the White House.  (“A generation from now, this solar heater can either be a curiosity, a museum piece, an example of a road not taken, or it can be a small part of one of the greatest and most exciting adventures ever undertaken by the American people: harnessing the power of the sun to enrich our lives as we move away from our crippling dependence on foreign oil.”)  As it turned out, “a road not taken” was the accurate description.  On entering the Oval Office in 1981, Ronald Reagan caught the mood of the era perfectly.  One of his first acts was to order the removal of those panels and none were reinstalled for three decades, until Barack Obama was president.

Carter would, in fact, make his mark on U.S. energy policy, just not quite in the way he had imagined.  Six months later, on January 23, 1980, in his last State of the Union Address, he would proclaim what came to be known as the Carter Doctrine: “Let our position be absolutely clear,” he said. “An attempt by any outside force to gain control of the Persian Gulf region will be regarded as an assault on the vital interests of the United States of America, and such an assault will be repelled by any means necessary, including military force.”

No one would laugh him out of the room for that.  Instead, the Pentagon would fatefully begin organizing itself to protect U.S. (and oil) interests in the Persian Gulf on a new scale and America’s oil wars would follow soon enough.  Not long after that address, it would start building up a Rapid Deployment Force in the Gulf that would in the end become U.S. Central Command.  More than three decades later, ironies abound: thanks in part to those oil wars, whole swaths of the energy-rich Middle East are in crisis, if not chaos, while the big energy companies have put time and money into a staggeringly fossil-fuel version of Carter’s “alternative” North America.  They’ve focused on shale oil, and on shale gas as well, and with new production methods, they are reputedly on the brink of turning the United States into a “new Saudi Arabia.”

If true, this would be the worst, not the best, of news.  In a world where what used to pass for good news increasingly guarantees a nightmarish future, energy “independence” of this sort means the extraction of ever more extreme energy, ever more carbon dioxide heading skyward, and ever more planetary damage in our collective future.  This was not the only path available to us, or even to Big Oil.

With their staggering profits, they could have decided anywhere along the line that the future they were ensuring was beyond dangerous.  They could themselves have led the way with massive investments in genuine alternative energies (solar, wind, tidal, geothermal, algal, and who knows what else), instead of the exceedingly small-scale ones they made, often for publicity purposes.  They could have backed a widespread effort to search for other ways that might, in the decades to come, have offered something close to the energy levels fossil fuels now give us.  They could have worked to keep the extreme-energy reserves that turn out to be surprisingly commonplace deep in the Earth.
And we might have had a different world (from which, by the way, they would undoubtedly have profited handsomely).  Instead, what we’ve got is the equivalent of a tobacco company situation, but on a planetary scale.  To complete the analogy, imagine for a moment that they were planning to produce even more prodigious quantities not of fossil fuels but of cigarettes, knowing what damage they would do to our health.  Then imagine that, without exception, everyone on Earth was forced to smoke several packs of them a day.

If that isn’t a terrorist -- or terrarist -- attack of an almost unimaginable sort, what is?  If the oil execs aren’t terrarists, then who is?  And if that doesn’t make the big energy companies criminal enterprises, then how would you define that term?

To destroy our planet with malice aforethought, with only the most immediate profits on the brain, with only your own comfort and wellbeing (and those of your shareholders) in mind: Isn’t that the ultimate crime? Isn’t that terracide?
Tom Engelhardt
Tom Engelhardt, co-founder of the American Empire Project, runs the Nation Institute's His latest book, co-authored with Nick Turse, is Terminator Planet: The First History of Drone Warfare, 2001-2050. His other most recent book is The United States of Fear (Haymarket Books). Previous books include: The End of Victory Culture: a History of the Cold War and Beyond, The American Way of War: How Bush's Wars Became Obama's, as well as of a novel, The Last Days of Publishing To stay on top of important articles like these, sign up to receive the latest updates from here.

Saturday, May 25, 2013

Chris Reynolds: Acceleration of summer Arctic sea ice loss

Summer Acceleration

by Chris Reynolds, Dosbat, May 23, 2013

I have recently outlined the changes in the Cryosphere Today Area index (CT Area), using anomalies to examine the changes from the long-term-average seasonal cycle. I've shown the changes in the CT Area anomalies (link), the autumn response to increasing open water in the summer season (link), and the recent June anomaly crashes (link). I have also covered research showing the majority of surface-based Arctic Amplification is a response to summer ice loss (link), and that this amplification is probably being understated by the GISS dataset (link). However, I have not addressed a substantial issue -- that of the summer acceleration loss of area when compared to the loss of winter area.

The ice edges within the Arctic at minimum and outside the Arctic at maximum are set by different regions at opposing times in the seasonal cycle; until recently the recession of the ice edge had been proceeding at very nearly the same rate, leading to only a small increase in annual range. 2007 changed that, as can be seen from Cryosphere Today (link), where 2007 is seen to usher in a steep increase in the annual range.

In the graphic to the left, the green trace (annual daily maximum) is read on the left-hand axis, and the red trace (annual daily minimum) is read on the right-hand axis. However, both axes are 6M km^2 across, and are merely offset to match the earlier period. From this it can be seen that, for much of the period, both maximum and minimum follow each other relatively closely. In other words, whatever caused the reduction in area in March and September, it seemed to be applied equally to regions geographically remote and removed in time by 6 months. The most reasonable cause of this, backed up by other reasoning, is that Anthropogenic Global Warming has been causing the loss; to argue for separate processes makes things get rather complicated very quickly. This period of decline of sea ice also covers a period of substantial volume loss; September lost 7,800 cubic kilometres of sea ice from 1979 to 2006.

However, since the 1990s, and to a far more marked degree since 2007, the two plots have diverged markedly. This is the Summer Acceleration.

Using the data I've previously calculated, I have broken down the April PIOMAS volume into the volume contribution from grid box cells with an effective thickness of less than 2-m thick, and the volume contribution from those cells whose effective thickness is more than 2-m thick. April is chosen as the peak volume month, a 2-m-thick demarcation is chosen because ice thinner than 2 m thick is typically thermodynamically-grown first-year ice and that over 2 m thick is typically mechanically-thickened multi-year ice. The graph covers 1978 to 2012.

It can be seen that while ice under 2 m thick has remained the same (growing in recent years), the volume decrease is from ice over 2 m thick. Furthermore, when the declining ice over 2 m thick is superimposed over a plot of daily minimum in CT Area, they match reasonably closely. I don't think this is accidental.

The peripheral seas outside the Arctic Ocean are where the sea ice maximum is set; during the period of the above graph they have always been seasonal, with no surviving multi-year ice, so their ice falls into the under-2-m-thick category. So whilst it may seem odd that ice volume in April would relate closely to conditions 5 months later within the Arctic, it is not odd at all because the ice over 2 m thick is all within the Arctic Ocean. The loss of thicker ice has been directly impacting the initial conditions for seasonal melt within the Arctic Ocean.

So it seems that volume in April is driving the loss of area in September. I don't think the reverse is true because volume has been declining from the thickest ice, away from the ice edge. This is shown by the decline from ice over 2 m thick, not from the first-year ice (2 m thick and under) that would form after the September minimum in the periphery of the pack (around the coasts of the Arctic Ocean). Furthermore, as can be seen in recent years, with the increase in volume from ice less than 2 m thick; thin ice is able to 'bounce back' from perturbations, which is a strong negative feedback (e.g., Tietsche et al., Bitz & Roe), whereas, having a longer persistence (being many years old), thicker older ice has more of a 'memory' of impacts and hence carries forward the forcing of anthropogenic warming.

Volume loss drives thickness loss because volume loss represents thinning and, as I've discussed previously, thinning increases open-water-formation efficiency (link). This can be appreciated using the same approach as Figure 2 of Keen et al. (2013), "A Case Study of a Modelled Episode of Low Arctic Sea Ice." However, I have calculated the following graphic from gridded PIOMAS data (link).

The grey plots are for all years 1978 to 2012, lighter greys for more recent years, darker for earlier. Red is the average of that full period, green is the post 2007 average, blue is the average for 2010 to 2012. The large swings for some years of thicker ice are due to transport of thicker ice in those years, leading to open water.

Going along the horizontal axis are thicknesses of PIOMAS modelled sea ice in April; these are broken down into 5-cm bands, then for each band I calculated the percentage of ice in that thickness band that melts out to give open water in September -- this percentage is given in the vertical axis. It is perhaps easiest to understand if I take a simple case where all the ice is only one thickness and use the red line as the long-term average.

If we had an ice pack that was uniformly 3.5 m thick, then using the graph, finding the 3.5-m increment on the horizontal axis, we can go across from there to find that we'd expect about 7% of the pack to melt out to open water by the end of the melt season in September. Now if we thin this imaginary ice pack to 2.5 m thick, we can use the red line to scan across and see that about 12% would melt out by September. But if we thin this pack by just 1 m more, to 1.5 m, now a massive 80% of the ice area melts out by September.

I have used gridded PIOMAS data to calculate the average thickness of the April ice pack north of 70N -- this is to bias the result in favour of conditions within the Arctic Ocean.

With average ice thickness dropping to below 2 m, we are now firmly in the region where the percentage melt increases rapidly, and non-linearly, with further reductions in April grid box thickness. What this means is that we can expect strong volatility in the sea ice in the years to come, and without some stabilisation of the April thickness, we will see this volatility manifesting itself as a succession of crashes in area and volume.

Whether or not we face a rapid transition still bothers me. I haven't changed my opinion back to being sceptical of a rapid transition, but I may still do so dependent on events. However, I don't think the case for it is much more persuasive than the case against.

The decline in volume has hit a critical phase; where compared with past decades virtually all the MYI volume has been eliminated from the Arctic Ocean. Will we see autumn ice growth stabilise the pack, or will further declines in volume cause such winter thinning that we will see a virtually sea-ice-free state in the pack within years? I don't know.

Because area and extent are readily obtained from satellite data, public attention tends to be focused on these metrics. However, the acceleration of the summer decline in area and extent is a result of the decline in volume.

A Rough Guide to the Jet Stream: What it is, how it works and how it is responding to enhanced Arctic warming

by John Mason, Skeptical Science, May 22, 2013

Barely a week goes by these days in the Northern Hemisphere without the jet stream being mentioned in the news, but rarely do such news items explain in detail what it is and why it is important. As a severe weather photographer this past 10+ years, an activity which requires successful DIY forecasting, I've had to develop an appreciation into what makes it tick. This post, then, is a start-from-scratch primer based on that knowledge plus some valuable assistance from academia into where the current research is heading. Because of its length and breadth of coverage, I've broken it up into bookmarked sections for easy reference: to come back here click on 'back to contents' in each instance.

Earth's Troposphere - an introduction

We live at the bottom of a soup of gases, constantly moving in all directions -- our atmosphere. Virtually all of our tangible weather goes on in its lowest major division, the Troposphere. This division varies in average thickness from about 9,000 m over the poles to 17,000 m over the tropics -- in other words, it's thinnest in cold areas and thickest in hot areas, because hot air is more expansive than cold air. Likewise it fluctuates in thickness on a seasonal basis according to whether it's warmer or colder. Above it lies the Stratosphere, while below it lies the surface of the Earth.

The junction with the stratosphere is known as the tropopause, and as the diagram below shows, it is a major temperature inversion: although it gets colder with height in the troposphere, at the tropopause it suddenly warms. The inversion is so strong that convective air currents, which involve parcels of warm air rising buoyantly through cooler surroundings,  fail to penetrate it. That is why the flat, anvil-shaped tops of convective cumulonimbus (thunderstorm) clouds spread out laterally beneath the tropopause, as though it were some ceiling in the atmosphere.
Earth's atmosphere
Above: section through the lower 100 km of Earth's atmosphere. The thick black zigzagging line plots typical changes in temperature from the surface upwards; height above surface is the left-hand scale and typical pressure with that height is the right-hand scale.

The troposphere, which this post concerns, can be divided into two subsections: an upper layer, known as the Free Atmosphere, and a lower layer, known as the Planetary Boundary Layer. The Boundary Layer usually runs up from the surface to about 1,000 m above it (sometimes a bit more, sometimes a bit less), but basically it's a relatively thin layer in which the air movements and temperatures are influenced not only by major weather patterns but also by localized effects relating to the interaction of the air with the planet's surface. Such effects include frictional drag as winds cross land areas, eddies, veering and lifting due to hills and headlands, and convection initiated directly by heat radiation from sun-warmed ground. Low-level air currents, such as the cool sea breezes that push inland from coasts on warm summer days, likewise aid and abet convection and thereby thunderstorm formation as they undercut and lift warmed air masses along zones of convergence -- where different air currents come together. These factors are all low-level forcing mechanisms that set air currents in motion or perturb existing currents.

Above the Boundary Layer, winds are directed by two factors: the gradients that exist between centres of high and low pressure (anticyclones and cyclones respectively) -- air will always flow from a high-pressure zone to a low-pressure zone -- and the modifying factor known as the Coriolis Effect, which is the force exerted by the Earth's rotation. In the Northern Hemisphere, it causes air masses to be deflected to the right of their trajectory, and this effect is strongest at the poles and weakest at the Equator. In the Northern Hemisphere, the effect is to make the winds around a high-pressure centre circulate in a clockwise manner and those around a low-pressure centre circulate in an anti-clockwise manner: on a larger scale, the Coriolis Effect helps to maintain the prevailing west-to-east airflow.

Although the weather charts seen on TV forecasts show only what is happening close to the surface, the forecasts themselves are made with much reference to goings-on in the upper troposphere. In upper-air meteorology, pressure patterns are as important as they are down here at the surface. Atmospheric pressure is simply an expression of the force applied by a column of air upon a fixed point of known area and is measured in pascals (Pa). Meteorologists use the hectopascal (hPa) because the numbers are the same whether expressed in hectopascals or the older unit, millibars.

The greater the altitude, the lower the atmospheric pressure because there's less air above. In meteorology, above-surface observations are made remotely with satellites and directly by weather balloons carrying measuring instruments. The results of the balloon ascents, called soundings, are plotted on charts at different pressure levels, some typical examples of which are as follows:

Atmospheric pressure variability with height above surface

Pressure at any given height can change quite drastically as weather systems move through, just as it does at the surface. Taking the UK as an example, as an Atlantic low-pressure system moves through and is then replaced by a large high-pressure area, the pressure over a few days at sea level can rise from 970 hPa to 1,030 hPa. The same applies aloft, but unlike surface charts, where the data are plotted in terms of pressure, the upper-air data are plotted in terms of geopotential. Geopotential is the height above sea level where the pressure is, say, 850, 500 or 300 hPa, and is measured in Geopotential Metres (gpm or gpdm).

Other properties of the upper air, such as temperature, are important, too. For example, storm formation in an unstable lower troposphere is markedly encouraged if cold, dry air is present aloft, which makes the rising warm, moist air much more buoyant, increasing the instability. Storm forecasters will look at soundings for indications that cold, upper air is either already present or is upwind and can be expected to be transported into the forecast area. The process by which air (with its intrinsic physical properties such as temperature or moisture content) is transported horizontally is known as advection, an important term that will appear elsewhere in this post.

Weather systems aloft - the Polar Front and the jet stream
The interaction of warm tropical and mid-latitude air and cold polar air is what drives much of the Northern Hemisphere's weather all year round. For a variety of reasons, the change in temperature with latitude is not gradual and even but is instead rather sudden across the boundary between mid-latitude and polar air. This boundary, between the two contrasting air masses, is known as the Polar Front. It is the collision zone where Atlantic depressions develop, and their track is largely directed by its position. The steep pressure gradients that occur aloft in association with this major, active, air mass boundary result in a narrow band of very strong high-altitude winds, sometimes exceeding 200 miles per hour, occurring just below the tropopause. Such bands occur in both hemispheres and are known as jet streams. The one in the Northern Hemisphere, associated with the Polar Front, is often referred to as the Polar jet stream. The greater the temperature contrast across the front, the stronger the Polar jet stream: for this reason it is typically strongest in the winter months, when the contrast between the frigid, sunless Arctic and the mid-latitudes should normally be at its greatest.
Section of the atmosphere, Equator-North Pole
Above: section through the atmosphere of the Northern Hemisphere. Air rises at the Intertropical Convergence Zone and circulates northwards via the Hadley and Ferrel Cells (sometimes separated by a relatively weak Subtropical jet stream) before meeting cold Polar air at the Polar Front, where the Polar jet stream is located. Graphic: NOAA.

Waves on the jet stream - upper ridges and troughs

The Polar jet stream is readily picked out on upper-air wind charts, as in the example below. This is a Global Forecasting System (GFS) forecast-model chart for wind speeds and direction of flow at the 300-hPa pressure level; in other words, at an altitude a little higher than the summit of Everest and not far beneath the tropopause. Highest winds are red, weakest blue. The most obvious thing that immediately catches the attention is that the jet stream doesn't always run in a straight, west-east line, even though that's the prevailing wind direction in the Northern Hemisphere.

jetstream chart, 300hPa level
Graphic: model output plot - Wetterzentrale; annotation: author

Instead, it curves north and south in a series of wavelike lobes, any one of which can half-cover the Atlantic. These large features, which are high-pressure ridges and low-pressure troughs, are known as Longwaves or Rossby Waves, of which there are several present at any given time along the Polar Front. A key ingredient in their formation is perturbation of the upper troposphere as the air travels over high mountain ranges, such as the Rockies. Warm air pushing northwards delineates the high-pressure ridges. Cold air flooding southwards forms the low-pressure troughs. The two components to jet stream flow -- west-east and north-south -- are referred to as zonal and meridional flows respectively. The straighter a west-east line the jet stream takes, the more zonal it is said to be. The greater the north-south meandering movement, the more meridional it is said to be.

In addition to the Longwaves, there are similar, but much smaller ridges and troughs, known as Shortwaves. The chart above also shows how, locally, the jet stream can split in two around a so-called cut-off upper high or low, reuniting again downstream. Longwaves, shortwaves and cut-off highs and lows all have a strong bearing on the weather to be expected at ground level.

Several factors are important with regard to the Polar jet stream and its effect on weather. Again taking the UK as an example, the position of the Polar jet stream is of paramount importance. If it sits well to the north of the UK, residents can expect mild and breezy weather, and occasional settled spells. The Atlantic storms are passing by to the north, so they only clip north-western areas. However, if the Polar jet stream runs straight across the UK, then the depressions will run straight over the country, with wet, stormy weather likely. If it sits to the south, depressions take a much more southerly course, bringing storms to Continental Europe, and, in winter, the risk of heavy snow for the southern UK, as the prevailing winds associated with low-pressure systems that are tracking to the south of the UK will be from the east, thereby pulling in colder continental air.

zonal and meridional jet flows
Above: typical zonal (red) and meridional (orange) jet stream paths superimposed on part of the Northern Hemisphere. Extreme meridionality can bring very cold air flooding a long way south from the Arctic, while warm air is able in a different sector to force its way into the far north. The most extreme version of this I have seen was on the morning of November 28th, 2010: at 06:00, parts of Powys (Mid Wales) were down to -18 C, whilst at the same time Kangerlussuaq, within the Arctic Circle in Western Greenland, was at +9 C  -- or 27 degrees warmer!! Graphic: author

In highly zonal conditions, weather systems move along rather quickly, giving rise to changeable weather. However, in highly meridional conditions, the Longwaves can slow down in their eastwards progression to the point of stalling, to form what are known as blocks. When a block forms, whatever weather type an area is experiencing will tend to persist. During some winters, for example, a blocking ridge forms in the mid-Atlantic, with high pressure extending from the Azores all the way up towards Greenland. Provided the block is far enough west, it can induce a cold northerly-to-easterly airflow over NW Europe, a synoptic pattern that brings cold weather and, in recent winters, heavy snowfalls.

To complete this section, here are a couple of Flash animations of different jet-stream patterns by Skeptical Science team-member 'jg' that illustrate how the waves progress eastwards. First, zonal, with the longwaves moving through briskly:

[Readers, please go back to the original site to look at these great animated illustrations of the "old" jet stream we knew and loved, and the new one that we are really not liking:

Next: meridional: the longwaves are progressing eastwards much more slowly in general. In a blocked scenario, imagine the 'pause' button has been pressed and the whole lot has stopped for a while:

[Readers, please go back to the original site to look at these great animated illustrations of the "old" jet stream we knew and loved, and the new one that we are really not liking: 

Now, let's move onto some of the important weather-forcing mechanisms that are associated with the jet stream and its wave patterns.

Positive vorticity - a driver of severe weather - and the jet stream

Another important factor associated with any jet stream is vorticity advection. The jet flowing around a lobe of cold polar air (an upper Longwave or Shortwave trough), orientated north-south, first runs S, then SE, then E, then NE, then N, i.e., its motion is anti-clockwise, or cyclonic. Watch a floating twig in a slow-moving river. As it turns a bend, it will slowly spin. It's spinning because the water upon which it floats is spinning -- it has vorticity. You can't necessarily see the water doing this, but the floating twig gives the game away! Vorticity is a measure of the amount of rotation (i.e., the intensity of the "spin") at a given point in a fluid or gas. And, in the air rounding an upper trough, anti-clockwise vorticity is induced. This is known as Cyclonic Vorticity (or frequently as Positive Vorticity).

How upper air patterns affect vorticity
Above: how the eastwards progression of upper ridges and troughs affects vorticity which in turn affects lift in air masses. Areas of positive vorticity advection (PVA) occur ahead of approaching troughs, aiding severe weather development, whereas areas of negative vorticity advection (NVA) cause air to sink, inhibiting developments. Graphic: jg.

Positive vorticity in the upper troposphere encourages air at lower levels to ascend en masse. Rising air encourages deepening of low-pressure systems, assists convective storm development and so can lead to severe weather such as heavy precipitation and flooding. As an upper trough moves in, air with positive vorticity is advected ahead of its axis in the process known as positive vorticity advection, usually abbreviated to PVA. Thus, to identify areas of PVA when forecasting, look on the upper-air charts for approaching upper Longwave or Shortwave troughs: PVA will be at its most intense just ahead of the trough and that is where the mass ascent of air will most likely occur.

The reverse, anticyclonic or negative vorticity advection (NVA) will occur between the back of the trough and crest of an upper ridge, due to the same process but with a clockwise (anti-cyclonic) spinning motion induced into the air as it runs around the crest of the ridge. In such areas, air is descending en masse instead of ascending. Descent is very adept at killing off convection and cyclonic storm development. Thus as the upper trough passes, severe weather becomes increasingly unlikely to occur.

Wind shear - a driver of severe weather - and the jet stream

Wind shear, involving changes in wind speed and/or direction with height, is an important factor in severe weather forecasting. Shear in which wind-speed increases occur with height (speed shear) is common, as you will notice when climbing a mountain: a breeze at the bottom can be a near gale at summit level. But in the upper troposphere, the proximity of the Polar jet stream can lead to incredibly strong winds. Speed shear is important in convective storm forecasting as it literally whisks away the "exhaust" of a storm, thus helping to prolong it: the storm's up-draught and precipitation core (down-draught) are kept apart, instead of the down-draught choking the up-draught. It's a bit like an open fire drawing well. The strongest speed shear occurs when the jet is racing overhead. In this environment, cumulonimbus anvils may stretch for many miles downstream due to the icy cirrus of the anvil being dragged downwind. When there's hardly any speed shear, the storm tops have a much more symmetrical shape to them.

Directional shear basically means that winds are blowing in different directions at different heights from the surface. Drawing from my experience in weather photography, I know that a warm early summer's day where the synoptic pressure pattern gives a light northerly airflow at say 850 hPa, coupled with some instability, is a consistently productive set-up for thunderstorms and funnel clouds. Why? Well, I live ten miles due east of the Welsh coast, surrounded by hill country. As warm sunlight heats the lower troposphere over the hills, air will begin to rise by convection: at the same time, a sea breeze will set in, flowing west to east inland from the coast. These two air currents will meet -- or converge -- along a linear front somewhere over the hills. Because the sea breeze is relatively cool, along the front it undercuts and lifts the warm air, strongly aiding convective storm initiation. In addition, the developing storms are moving north-south along their steering flow, but the air flowing into the western side of their up-draughts -- the sea breeze -- is coming in at right angles to that. That's a lot of low-level, rotation-inducing, directional shear, more than sufficient for funnel cloud development, something I have witnessed along sea-breeze fronts on a number of occasions.

In situations where major instability (and therefore the potential for severe storms) is present, directional shear can be of critical importance in the formation of tornadic supercells, in which the up-draught is rotating strongly from near ground level, all the way up to the top of the storm cloud. These tend to be the most violent members of the thunderstorm family because of the persistence and strength of their up-draughts.

Above: speed shear revealed by a convective shower cloud. High-speed upper winds are dragging the upper parts of the cloud well over to the right. Below: speed and directional shear revealed by a small supercell thunderstorm: the up-draught is tilted R-wards so that the rain is falling well over to the R, several miles down wind from the up-draught base. The seat of the up-draught is indicated by the dramatically lowered rotating wall cloud reaching halfway down to the sea from the overall cloud base. This storm persisted for over 90 minutes as it tracked across over 100 km of the seas and mountains of Wales. Photos: author.

Speed-and rotational shear

Jet streak development along the jet stream - a driver of severe weather

Within the overall circumglobal, ribbon-like, wind field of the Polar jet stream, there occur local sections with much stronger winds than elsewhere. These are called jet streaks. They form in response to localised but major temperature gradients, and they move around the lobes, following the troughs and ridges, and affect these in their passing, strengthening them as they move in, and weakening them as they move out. They also influence the weather below, even if moving in a fairly straight line when there are few long-wave ridges/troughs about.

Graphic: model output plot  Wetterzentrale; annotation: author

Fast jet streaks with winds as high as 200 knots pull in air upstream (to their west) at what is called an Entrance Region and throw it out down stream (to their east) at what is called an Exit Region. These are further subdivided, as in the diagram above, into Left (to the north) and Right (to the south). Because the behaviour of air currents is determined by the interaction of the Coriolis effect and the pressure gradient, the Right-Entrance and Left-Exit regions of jet streaks are areas where winds aloft diverge, allowing air below to rise. This in turn further encourages storm development. In Right-Exit and Left-Entrance regions, the opposite occurs, with upper-level winds converging leading to air sinking and inhibiting storm formation. The reason, in terms of storm development, it is divergence as opposed to convergence that is important at height (the opposite being the case at low levels) is that converging air at height cannot go upwards because of the effective ceiling provided by the tropopause. There is only one vertical direction in which the air can freely go -- downwards.

What this means on the ground is that if your area is near to a developing low-pressure system or a convectively unstable air mass, and an upper trough is approaching with a jet streak heading towards the base of the trough with its Left-Exit region heading straight for where you are, you have the ingredients for explosive severe weather development. The low can deepen intensively to bring a storm system with tightly packed surface isobars giving severe gales and flooding rains. Alternatively, convection may lead to the development of severe thunderstorms because that critical combination of mass ascent and high shear is in place.

Northern Hemisphere atmospheric circulation patterns: the Arctic and North Atlantic Oscillations

Atmospheric pressure patterns in the Northern Hemisphere feature several semi-permanent features and patterns. By semi-permanent I mean that areas of high and low pressure are normally to be found in certain places or that pressure patterns tend to switch from one type to another and then back. The low pressure of the Intertropical Convergence Zone is a good example of a semi-permanent feature: it is normally close to the Equator, but it is not always in the same place -- it can shift a little north or south in its position. A good example of a switching pressure pattern occurs in the Arctic and is known as the Arctic Oscillation (AO). When atmospheric pressure over the Arctic is low and pressure over the mid-latitudes is high, the AO is said to be in its positive phase, which supports a tight and fast-moving zonal, west-to-east airflow -- the Polar Vortex -- as the diagram below shows:

Arctic Oscillation - normal or positive phase
Graphic: author

The next diagram is an example of what happens when the Arctic Oscillation is in its negative phase, with high pressure over the Arctic:

Arctic Oscillation - negative
Graphic: author

The flow becomes more meridional, with big meanders occurring in the long-wave ridges and troughs that then tend to move eastwards much more slowly. Rossby Wave theory predicts this, but there is a simple analogy: think of a river's flow weakening as it leaves the mountains and enters the lowlands, where it becomes sluggish and meanders develop and propagate seawards along the flood plain over many decades. A negative Arctic Oscillation pattern with these high-amplitude longwaves has the effect of permitting warm air to penetrate much further north (in the ridges) and cold air to plunge much further south (in the troughs), something that is obviously of relevance in the resultant weather conditions.

The North Atlantic Oscillation is a numerical index that describes the average difference in surface air pressure between Iceland and coastal southern Europe (the data sources used are Reykjavík in the north and either the Azores, Portugal or Gibraltar in the south). Although daily data are available, the NAO is typically expressed in monthly or seasonal terms.

Here's the NAO in its positive phase:

North Atlantic Oscillation - positive phase
Graphic: author

With a positive NAO, the Atlantic pressure pattern essentially features a dipole, with low pressure over Iceland (the Icelandic Low) and high pressure off the Iberian coast (the Azores High). These are both good examples of semi-permanent features -- if they were not so commonplace, they would not have been so named. South of the Icelandic Low, the southwesterlies blow mild air and moisture towards NW Europe, whilst SW of Iberia, on the southern flank of the Azores High, we find the northeasterly Trade Winds (so important to merchant shipping back in the days of sailing).

Now let's see a slightly negative NAO:

Negative North Atlantic Oscillation
Graphic: author

The low- and high-pressure centres are still there but are both much weaker, leading to a strongly reduced pressure gradient between the two and a slacker airflow. With the southwesterlies much suppressed, colder winter weather can develop more easily over NW Europe. But what happens if the NAO is strongly negative, as it was during the cold spell of March 2013 when it dipped at one point to a phenomenal value of -5 (typical values are between +2 and -2)?

Strongly negative North Atlantic Oscillation
Graphic: author

The normal pressure pattern is reversed: pressure over Greenland and Iceland is high, whilst the mid-Atlantic is dominated by low pressure. In winter, this has the effect of vigorously pulling in moisture from the Atlantic but also cold air from either northern or eastern sources, a mixture which can lead to severe weather developing: the pressure pattern in the diagram is similar to those of both January 9th, 1982, and March 22nd, 2013 -- dates that have gone down in UK weather history for the unusually severe blizzards that occurred. The March 2013 blizzards were disastrous: it was very late in the winter to have such cold over here, and the losses to farmers of livestock have been significant, with drifting snow having buried sheep, cattle and ponies to a depth of five metres or more in places.

buried vehicles, Mid Wales, late March 2013
Above: the late March 2013 blizzards struck parts of the UK with a fury not seen in decades. A strongly negative NAO/AO with blocking patterns in the jet stream can bring a complete spectrum of weather extremes and this is just one of them. This was on March 29th, a week after the storm occurred. Photo: author.

Another pressure pattern that has been recognised in recent years and which has been linked to the rapid warming of the Arctic is the Arctic Dipole:

Arctic Dipole
Graphic: author

In the Dipole pattern, high pressure sits over the Canadian side of the Arctic and low pressure sits over the opposite, Siberian, side. This setup has some similarity to a negative Arctic Oscillation phase in that the strong west-east zonal flow is not supported but, more importantly, two things are facilitated: cold air is churned out on the North Atlantic side of the system and may flood southwards for great distances, but conversely warm air is pulled into the Arctic on the Pacific side. The Dipole pattern is thus a major heat exchanger between the Arctic and the mid-latitudes.

The Arctic and North Atlantic Oscillations tend to behave in step with one another, as the following superimposed plots show:

North Atlantic and Arctic Oscillations, 1950-2012

In the plots, the thin lines are the NAO (with a black trend line denoting the moving average) and the bars the AO. It is apparent that there are periods dominated by either positive or negative values in both indices: the 1990s were strongly positive, whereas the late 2000s, which have featured several very cold winters, have seen many and often strongly negative excursions.

Climate change and the future: how will the jet steam and pressure-patterns respond?

Wave theory tells us that the west-east progression of the Rossby waves is influenced by their size: larger waves move more slowly. Negative NAO/AO setups promote such meridionality and, according to recent research, that meridionality seems to be on the increase. A possible cause of this effect is the warming of the Arctic, which has become so profound (twice that of the rest of the world) that it has been given a term: Arctic Amplification. Arctic Amplification manifests itself not only in the temperature record but also in physical features like the strong and in 2012 record-shattering seasonal melting of Arctic sea ice, a process which itself leads to more accumulation of heat energy as the ice-free sea water absorbs incoming solar radiation that would have otherwise been mostly reflected back out into space.

Further heat, independent of sea ice or snow cover, is transported into the Arctic by the increased global water-vapour content of the atmosphere, a factor that has three effects. Firstly, water vapour is of course a potent greenhouse gas: secondly, as moist air cools as it comes into the Arctic the water vapour condenses, releasing latent heat; and thirdly, condensation forms clouds, increasingly regarded as heat-trapping agents. Such warming is particularly important in the sunless winter months and at higher atmospheric levels: at 500hPa and above it is the major component of Arctic Amplification, compared to the loss of albedo due to melting sea ice and snow close to the surface. Arctic Amplification is a relatively new phenomenon which has emerged as a signal in recent years: how it will interact with variations in existing circulation patterns like the NAO/AO, ENSO (the El Nino-La Nina oscillation) and the PDO (Pacific Decadal Oscillation) remains to be fully understood. However, in a system full of variables, it generally holds that if major variables undergo major changes there will be knock-on effects elsewhere in the system.
pre-industrial temperature-gradient
Above: a very simplified diagram of how things were prior to Arctic Amplification, with a steep temperature gradient between the warm Equator and the cold Arctic. below: the situation now -- while the low and mid-latitudes have warmed a bit, the Arctic has warmed a lot. As a consequence, the temperature gradient between the two has a gentler slope. Graphic: author
arctic amplification

As the simple diagram above shows, one consequence of Arctic Amplification is to reduce the temperature gradient between the Arctic and the warmer latitudes. Given that the strength of the jet stream is influenced by the magnitude of the temperature gradient, it follows that warming of the Arctic could lead to a weakening of the jet stream and a greater tendency to meander as it slows down [Readers, note that the jet stream's west-to-east progression slows down, not its wind speeds, which may even increase]. As this meandering develops, troughs may be expected to extend further southwards and ridges to push further northwards. However, recent research suggests a greater northwards component to this behaviour (the ridges are pushing further northwards than the troughs are nosing southwards), meaning that in overall terms the Polar jet stream has moved northwards. The wavier state of the jet stream also causes more mixing of warm and cold air in the Northern Hemisphere. More importantly, situations where the eastwards progression of these upper waves becomes sluggish or stalls lead to prolonged weather conditions of one type or another. Unseasonably cold, wet, hot or dry conditions that last for weeks at a time can be just as destructive as storms: their effects on biodiversity and agriculture can be disastrous, leading variously to reduced crop yields, crop failure, biodiversity loss and wildfires, to name but a few effects.

Recent research into the Polar jet stream has been focused on the 500-hPa height/windfield, because for a number of reasons it is easier to work with. This lies below the height of the strongest jet stream winds, but a look at the charts below, 300-hPa windfields above and 500-hPa windfields beneath, shows that the tightest gradients and strongest winds are colocated.

300hPa winds, 14th Arpil 2013

Above: 300-hPa windfields for April 14th, 2013, 0600z. Below: plot for the same date and time at the 500-hPa level. The tightest gradients and strongest winds occur in the same places, meaning the 500-hPa pattern can be used to make deductions about the 300-hPa pattern. Model output plot - Wetterzentrale
500 hPa winds, 14th April 2013

The research has indeed found a correlation between 500-hPa-height autumnal wind speeds and Arctic sea ice annual minima -- both have gone down, as the following graph shows:
September sea ice extent versus high altitude wind strengths, 1980-2010
Above: how the drop in high-altitude winds in autumn over the past 30 years (solid line) has closely tracked the decline in Arctic sea ice (dashed line). Graphic: Jennifer Francis, based on data from the National Center for Environmental Prediction, National Center for Atmospheric Research, and National Snow and Ice Data Center.

That's for autumn, and in recent years blocked patterns have often persisted into the winter, but what about the rest of the year? The tendency for the jet stream to slow down and meander more seems to have become a summer feature, too, well before the annual sea ice minimum. However, there is another important regional and seasonal variable: lying snow, both in the Arctic and sub-Arctic. This snow is melting progressively earlier over time: the sooner it melts, the sooner the soil beneath is warmed by the spring sunshine. There has been approximately 2 C of late spring-early summer warming over high-latitude land areas since the mid-1980s, heat which is contributing to the Arctic Amplification effect during the summer months. Again, the probability is that Arctic Amplification can slow the jet stream and amplify its waves into slow-moving blocking patterns, bringing prolonged weather of one kind or another to various parts of the Northern Hemisphere.

In researching this post I had a useful discussion with Dr Jennifer Francis of the Institute of Marine and Coastal Sciences at Rutgers University, New Brunswick. Jennifer has published extensively on Arctic climate change and in recent years has been studying changes to the jet stream. I finished my Q&A session with a look at the future. What, I wanted to know, was the outlook? Would any pattern of change to the jet stream be linear in fashion? Jennifer replied:
"Hard to say if it's linear or otherwise -- not enough years of data yet, and it's not clear if models are able to capture the behavior realistically. Some recent papers suggest they don't simulate blocking patterns well, for example, which are key for extreme weather. We have looked at a 4xCO2 run of the NCAR GCM, however, which suggests that (like the real atmosphere) the 500-hPa zonal winds will weaken substantially in all seasons (not just fall, which is the strongest signal in the real world), and also that the flow will become more meridional, that is, the ratio of north-south winds relative to the total flow will increase. I think the tendencies we're seeing in the real world will continue to increase. As we lose all the summer ice, the response in the fall may plateau somewhat (although Arctic Amplification will continue via the other factors), but as ice in the other seasons declines, we should see the response become stronger all year long."
That modelling jet stream behaviour is difficult should come as no surprise: we are entering Terra Incognita here, with Arctic sea ice melting far more rapidly than most previous predictions have suggested. It makes sense to suggest that -- if sea ice melt is a prime driver here -- that once all the variability in the system is 'used up' (i.e., when we see a seasonally sea-ice-free Arctic), then we should see a plateau effect in autumn/fall, but this is but one part of Arctic Amplification and the way the other variables such as poleward water vapour transport behave is just as important.


The Arctic has warmed about twice as much as the rest of the world, and the responses to the warming by some variables such as sea ice have greatly exceeded expectations. Evidence is mounting to indicate that the response of the jet stream to this new thermal regime has been to tend to slow down [its west-to-east progression is slowing] and meander more, with a greater tendency to develop blocking patterns. In the UK, the run of wet, dull summers and the run of prolonged cold outbreaks in recent winters show what can occur when the jet steam behaves in a meridional and sluggish fashion. At the moment it's more active: on the morning that this was written, April 14th, 2013, a 130-knot jet streak was racing NE over the northwestern UK on the eastern limb of a deep upper trough: it was mild and wet with a southwesterly gale blowing but with alternating bouts of sunny and cloudy, wet weather forecast for the week ahead. Changeable weather is the norm for NW Europe: prolonged periods of any weather type are historically atypical and may be noteworthy when they occur.  Clearly, we need to get a good handle on what is going on here and how future responses may play out in our weather patterns: already it seems to be the case that we are going to have to develop greater adaptability to a greater range of prolonged weather extremes. How that plays out in terms of agriculture and economics remains to be seen, but there should be no room for complacency.