Dr. Roger Pielke Sr. writes:
Candid Admission By UCAR – “Blocking The Way – Predicting The Atmospheric Detours That Lead To Weather Troubles”
There was an interesting article in the Fall issue of the UCAR Magazine titled by Bob Henson titled
Blocking The Way – Predicting The Atmospheric Detours That Lead To Weather Troubles
Although embedded in the article are the usual claims by some that are quoted that future climate can be skillfully inferred from what the models already produce, this article includes text and quotes by several climate scientists who candidly discuss limitations in current climate models to skillfully predict a major aspect of the atmospheric circulation. The article focuses on what are called “blocks” and it is these restrictions to the east-west movement of weather systems that can persist for months that produces record weather such as the 2011 heat and drought in Texas.
Excerpts from text of the article read [highlight added]
The concept of atmospheric blocking might not be familiar to the general public, but millions have come face to face with the results of spectacular blocks over the last couple of years. Every so often, a dome of upper-level high pressure sits in place for a few days, sometimes as long as several weeks. A major block can produce seemingly endless stretches of blazing heat or bitter cold. It also blocks the typical eastward flow of the polar jet stream (thus the label “blocking”) and throws storm systems far from their usual tracks. Along those displaced paths, the storms can generate successive bouts of heavy rain or snow. By the time it dissipates, a major block may leave behind a whole stack of broken weather records and an array of disastrous consequences.
Relentless high pressure over Russia led to unprecedented summer heat in 2010, with estimates of more than 10,000 people killed either directly or indirectly. Toward the south side of the Russian block, unusually strong monsoonal flow sent vast amounts of moisture into Pakistan, leading to catastrophic flooding. And when huge bubbles of high pressure popped up in and near Greenland over the last two winters, cities from Washington, D.C., to London found themselves grappling with heavy snow even as parts of the Arctic experienced periods of record mildness.
The recent high-profile blocks have put questions of predictability on the front burner. There’s more than a touch of mystery in what makes a block form and dissipate. Phenomena such as El Niño tend to favor blocking in specific areas, but it’s still difficult for weather prediction models to peg the start and stop times of a particular block. And climate models tend to underestimate the frequency of blocking, which could have an influence on their seasonal-scale averaging of future climate.
“Blocking highs significantly influence climate events over large portions of the Northern Hemisphere,” notes James Hurrell, the new head of the NCAR Earth System Laboratory.
In the case of Russia, the team’s initial report pointed to a block that was unprecedentedly strong and unusually long-lasting, with a particularly intense stretch from early July into mid-August. On average, the region gets only about 10 blocking days during those two months. The strength and duration of the 2010 block allowed plants and soil to dry out, which helped send surface air temperatures into uncharted territory. Forest fires and long-burning fires in peat bogs poured smoke into the stagnant block, which degraded air quality and added to the heat wave’s deadly impact.
How much could global warming have contributed? Although the heat wave unfolded during one of the warmest years on record globally, the NOAA group found no evidence of a significant trend in blocking during July over western Russia in the last 60-plus years of upper-air records. And they noted that average July surface temperatures have not risen significantly over western Russia, unlike some other parts of the world and the world as a whole.
Climate models don’t yet have a firm enough handle on blocks to tell us exactly how they’ll change in coming decades. NCAR’s Neale is one of three co-chairs of the working group that oversees the atmospheric component of the NCAR Community Earth System Model (CESM) and its predecessor, the NCAR Community Climate System Model (CCSM4). By and large, he says, climate models do a good job depicting extratropical cyclones, the lows that regularly sweep across midlatitudes. Blocking is a different matter.
“The jury is still out on how blocks develop, how they become persistent, and how they break down,” says Neale.
According to NCAR’s Clara Deser, “The future state of the NAO is highly uncertain due to the large amount of internal variability, even on 50- to 100-year time scales, compared to the changes driven by increased levels of greenhouse gases.” Deser has carried out several model-based analyses of future ocean-atmosphere interactions in the North Atlantic and Pacific.
As climate models get a better handle on blocking and on Arctic sea ice, they may paint a more consistent and realistic picture of details in the Northern Hemisphere’s future climate. “There is not really a robust statement yet on the future of blocking,” says Scaife.
This article is an informative summary of this subject, and the entire article should be read.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
OK, I agree with the argumentation, but where are the cold waves?
It’s blocking highs to the west of Ireland that produce cold winters in the UK, and blocking highs to the east of the North Sea which produce mild winters and dry autumns. It what directs the daisy chain of low pressure areas kindly provided by the geography of Newfoundland north or south of the British isles.
According to NCAR’s Clara Deser, “The future state of the NAO is highly uncertain due to the large amount of internal variability, even on 50- to 100-year time scales, compared to the changes driven by increased levels of greenhouse gases.”
I don’t think these people are realy well versed into what the NAO is about.
I have looked into the NAO-AMO relationship in some details. If you have enough patience (just ignore all the correlation numbers) to get through the article you will find number important relationships between atmospheric pressure and the Sea surface temperature.
If you follow the initial link
http://www.vukcevic.talktalk.net/theAMO-NAO.htm
Does that mean if you detonate high explosives at this high altitude, in the areas of these blocks, you could create low pressure spots that might dissipate or minimize the block? Maybe just fly a fleet of airplanes through, re-route the closest commercial flight lane? I think some experimentation with weather needs to take place. AGW is crap, but someday, we may want to know how to bleed off rain from a large storm, bust hurricanes over the oceans, break heat waves or even warm up glaciers, when they start forming for the next ice age. It may be 20 years or 500 years away, or more, but another ice age is inevitable, without this type of capability. I’d rather see UN (or US) studies, limited experimenting and money spent on something active, than on activism and trying to raise money.
Note that Richard Attenburgh in his final programme in the Frozen planet series is down to cheer lead for global warming.
If the money wasted on Great Society and its massive social destruction
had been spent on a space program with the scale of 2001, Space Odyssey,
we would have huge solar-power sats beaming at the water frequency
to locally inject gigawatts per square kilometer at key ‘butterfly-effect’ spots.
With enough 24-hour model-ahead capability,
a dozen such sats could control all large-scale weather systems.
A theory of Mobile Polar Highs by prof. M. Leroux becomes vindicated, slowly.
http://en.wikipedia.org/wiki/Marcel_Leroux
Not a modeller, but observer and thinker.
Casper says:
December 8, 2011 at 9:09 am
OK, I agree with the argumentation, but where are the cold waves?
I’m not real sure of your question, however: About 15 years ago (at this very time of year) our temps went to 17 F below and didn’t get above zero for 2 weeks. Location is central Washington State. Such episodes are sufficiently rare that folks are not prepared. Students at the local University have come from all over the warmer world without cold weather gear. Anyone have a coat they can lend out? This was before local wind turbines so no issue there but the lack of wind causes air stagnation and the State Dept. of Ecology invokes burn bans. Just when extra heat is needed, using your ‘stand-by’ wood stove can bring a knock on the door. For outside animals these are tough times – especially for those whose owners never expected such cold and don’t have structures and heated water tanks.
If this is what you mean by a cold wave – I know a bit. Not world record breaking but problems occur because they are rare and memories are short.
In 1976 the UK and much of Western Europe had a drought lasting 6 months. The whole country turned brown. Reservoirs turned to dry mud and water standpipes were set up in the streets. Instead of rain we had little particles of windblown Saharan sand falling from the sky.
This was all down to a blocking high off the Iberian peninsular. Wet Atlantic weather was blocked, and a continuous hot, dry stream came up from Africa.
Of course, there was no talk of global warming then, especially as Newsweek was reporting the next Ice Age.
Years later, I saw a scientist telling Congress that the heatwave in the US was down to CO2 (it must have been 1988) and thinking “typical – the Brits just take the weather, the Yanks have to make it into a crisis’. Apologies for the racism:-)
Now if only the UK had come up with the global warming scam in 1976 we could have been world leaders before anyone had even heard of Phil Jones…
>>Gareth Phillips says: December 8, 2011 at 9:17 am
>>It’s blocking highs to the west of Ireland that produce cold winters in the
>>UK, and blocking highs to the east of the North Sea which produce mild winters
Not quite. If you can imagine a high pressure over Scandinavia and the northern North Sea, you will end up with strong easterly flows over the UK. Now during the summer, that is a warm wind. But in the winter, this situation will bring the UKs coldest weather. And if you have a short sea-track, there will be light snow, but if you get s longsea-track more from the NE, you can get heavy snow.
It is this type of blocking high that caused the UKs very cold winters over the last two years – with easterly rather than northerly winds.
.
@Casper,
You mean things like this? http://en.wikipedia.org/wiki/Cold_wave
“Winter of 2010–2011 in Great Britain and Ireland – It was referred to as The Big Freeze by national medias in both United Kingdom and Ireland and it was the coldest winter in Britain for 31 years with an average temperature of 1.51C. The UK had its coldest December ever, since records began in 1910, with a mean temperature of -1°C. It easily broke the previous record of 0.1°C, set in December 1981.”
” A cold wave affected much of the Deep South in the United States and well into Florida in January and February 2010.”
” 2009-2010 European Cold Wave – At least 90 are confirmed dead after record low temperatures and heavy snowfall across Europe causes travel disruption to much of the continent including the British Isles, France, the Low Countries, Germany, Austria, Italy, Poland, the Baltic States, the Balkans, Ukraine and Russia. Coldest winter for 30 years in the UK with the longest sustained cold spell since 1981. Temperatures in the Italian Alpine peaks have reached low to an extreme of -47 °C.”
And more.
Blocking occurs more often when the sun is less active.
The polar vortices, instead of descending in a single intense high pressure cell over each pole are diverted and split up as the flow of air descends so that instead we see two or three seperate high pressure cells around the poles with the poles themselves covered by areas of relatively low pressure.
I have described a possible mechanism previously here and elsewhere. An active sun cools the stratosphere at the poles to facilitate a single descending high pressure cell. A less active sun allows the stratosphere at the poles to warm a little and that warming in the stratosphere above the poles obstructs, diverts and breaks up the downward flow.
Those 2 or 3 high pressure cells are then free to migrate equatorward as observed by Marcel Leroux (mentioned above) and it is those high pressure cells that divert the mid latitude jets and distort them into loops across much larger areas. Often those loops are persistent for indeterminate periods of time but can migrate around the globe as it spins giving individual regions a succession of anomalous weather types.
That greater meridionality exerts a net cooling effect on the globe as follows:
i) Air flows from equator to pole and back again become more direct facilitating an increased rate of energy flow through the climate system from surface to space (via faster equator to pole energy transfer).
ii) The length of the lines of air mass mixing become much longer producing greater global cloudiness and albedo to reduce solar energy input to the oceans. I prefer this explanation for increased cloudiness when the sun is inactive to the Svensmark cosmic ray hypothesis.
Furthermore I think that the albedo changes from such changes in cloudiness are actually larger than, and occur before, any albedo changes that might be induced by increased snow and ice around the poles. I think that the focus on polar snow and ice as a primary driver of global albedo is incorrect. It is global cloudiness that changes first and the polar ice cover merely follows the lead of the cloudiness changes.
The article
http://en.wikipedia.org/wiki/Lorenz_attractor
contains the phrase “In addition to its interest to the field of non-linear mathematics, the Lorenz model has important implications for climate and weather prediction. The model is an explicit statement that planetary and stellar atmospheres may exhibit a variety of quasi-periodic regimes that are, although fully deterministic, subject to abrupt and seemingly random change.”
I what way has anthropogenic CO2 made our climate experience worse than it would have been?
Worth mentioning that blocking increases during solar minima – and we’re in a big one right now.
Lockwood et al 2010 says it is a northern Europe regional effect, but given the blocking events in both northern and southern hemispheres lately it seems to me to be pretty much global in scope.
If so then the GCM’s won’t correctly model blocking events until they include solar magnetic effects. And if they do that properly it will drop the modelled climate sensitivity right down to Prof Lindzen’s value. Which would be inconvenient for the CAGW establishment to say the least.
@ur momisugly WAM,
Right on! Leroux has been describing these since his 1993 Global and Planetary Change paper on Mobile Polar Highs.
All what Leroux has been explaining is happening.
http://ddata.over-blog.com/xxxyyy/2/32/25/79/Leroux-Global-and-Planetary-Change-1993.pdf
Dave D says:
December 8, 2011 at 9:28 am
Does that mean if you detonate high explosives at this high altitude, in the areas of these blocks, you could create low pressure spots that might dissipate or minimize the block? Maybe just fly a fleet of airplanes through, re-route the closest commercial flight lane? I think some experimentation with weather needs to take place. AGW is crap, but someday, we may want to know how to bleed off rain from a large storm, bust hurricanes over the oceans, break heat waves or even warm up glaciers, when they start forming for the next ice age. It may be 20 years or 500 years away, or more, but another ice age is inevitable, without this type of capability. I’d rather see UN (or US) studies, limited experimenting and money spent on something active, than on activism and trying to raise money.
==========
From:
http://webphysics.iupui.edu/warmup/iupui_archive/hurricanes.html
“Hurricanes are among the most powerful of all natural phenomena, and by far the most powerful storms. At its peak, a severe storm may have a total power near to 1015 Watts: about 3,000 times the total electrical power generated in the world. This is equivalent to exploding 500,000 atomic bombs per day (the little ones that were used at the end of WWII).”
The length of the lines of air mass mixing become much longer producing greater global cloudiness and albedo to reduce solar energy input to the oceans.
Stephen, interesting hypothesis. Is there any empirical data to support it?
What I want top see them model is: A blocking pattern that sends a big loop in the jet stream up to Greenland for three hundred years, pushing warm water into the coastal areas so you can swim without hypothermia, as the Vikings did, and melting the permafrost so you can grow grain, as the Vikings did. Meanwhile it must remain cold, or even colder, over the rest of the world.
Five years ago I would bring up the Greenland Vikings and the MWP to Alarmists, and I was always told it was merely a “local” event.
I always thought to myself, “Wow! That must have been one heck of a blocking pattern! We are lucky it didn’t flip the whole planet upside down!”
It’s odd they didn’t tweak the computer models to recreate the event. They’ve modeled everything else. But maybe there are some things even models can’t do.
The blocking highs are the result of the lunar declinational tidal effects, when the solar and lunar declination at culmination are about the same angle. Yes Leroux had the MPH movement and timings mechanism down, but did not see the cause as the lunar declinational tides in the atmosphere. Including the lunar atmospheric tidal effects will explain most of the problems they still have in predicting the locations and timing of their occurrences.
http://research.aerology.com/supporting-research/leroux-marcel-lunar-declinational-tides/
“Stephen, interesting hypothesis. Is there any empirical data to support it?”
No one has ever tried measuring it so far but common sense and a look at a pressure chart of the globe when it has strongly meridional jets makes it look pretty obvious to me.
You need a longer piece of rope to join two points if it loops about along the way and there is more material in a longer rope after all.
Richard Holle says:
December 8, 2011 at 2:52 pm
“The blocking highs are the result of the lunar declinational tidal effects, when the solar and lunar declination at culmination are about the same angle”
I think that could work in the short term but it doesn’t deal with the millennium scale shifting from MWP to LIA to date.
I have proposed a bottom up oceanic effect operating in conjunction with the top down solar effect sometimes supplementing it and sometimes offsetting it because I couldn’t see Leroux’s top down effect as accounting for the wide range of variability that we actually observe or for the number of short term failures of correlation with solar activity.The correlations with solar activity are very good on the millennial timescale but the shorter the timescale the worse it gets as Leif never tires of telling us.
I don’t have a problem with lunar/solar effects helping to drive the bottom up effect by creating ocean cycles, or even planetary alignments doing so, but in the latter case I would have thought that any such planetary effects would have to operate via the solar cycles otherwise they would be swamped.
Anyway, whatever forces are in play, it is the shifting of the entire climate zone network that operates as a negative system response to whatever is thrown at it. By that means the rate of energy flow through the system is modulated as necessary to limit changes to the system energy content (energy distribution is another matter).
In the Pacific Northwest, a winter stationary low-pressure area in the Gulf of Alaska is usually indicative of warm wet weather, often called ‘The Pineapple Express,’ coming up from the South West. On the other hand, a winter stationary high in the Gulf of Alaska sets up the Pacific Northwest for invasion by cold, dry, Arctic air. Significant snow events in the Seattle area may occur if a mobile low-pressure center moves east across Oregon while this Arctic air is in place. In each case, the high or low-pressure region in the Gulf is often described as part of an ‘Omega’ blocking pair.
Once again Stephen proposes a cause and effect without any actual measurements or maths. We are all aware of the glancing Solar IR at the poles. It begs the question, does the tiny CHANGE in active Sun, sleepy Sun IR have what it takes to create the affect Stephen talks about? For sure, Stephen does not know. And he isn’t going to come up with a plausible mechanism or the maths to go along with his theory either. He is waiting for someone (anyone?) else to do that. But doen’t ask me. I’m clueless.
Can’t spell either. …don’t…
By the way, I’m home sick with a migrain. Snark has been fueled by medicine downed with hot spiced wine. Word to the wise.