# What Is This Polar Vortex That Is Freezing the U.S.?



## ae1905 (Jun 7, 2014)

blogs.scientificamerican.com
Mark Fischetti

[HR][/HR] _Editor's note (1/4/18): This week's deep freeze is being caused by the same mechanism that iced the Eastern U.S. three years ago. Our explanation, written at that time, appears below.
_
As I write these words, temperatures across half the U.S. are plummeting like a rock. Extreme lows are forecast by tonight: -32 degrees Fahrenheit in Fargo, N.D.; -21 degrees F in Madison, Wisc.; -15 degrees F in Chicago and Indianapolis, according to the National Weather Service. Wind chills will reach a bizarre 60 degrees below zero F in some places, freezing exposed skin within one minute. That number is more typical for Mars—at night, according to the Curiosity rover NASA has free-wheeling over there.

As each hour passes, more and more television and radio reporters are attributing the insane cold to a “polar vortex” up in northern Canada. Vortex, yes, but upper Canada? Not exactly. One forecaster called the beast a hurricane in the Arctic, which is dramatic but wrong. So what is this mysterious marvel and why is it invading America?

The polar vortex is a prevailing wind pattern that circles the Arctic, flowing from west to east all the way around the Earth. It normally keeps extremely cold air bottled up toward the North Pole. Occasionally, though, the vortex weakens, allowing the cold air to pour down across Canada into the U.S., or down into other regions such Eastern Europe. In addition to bringing cold, the air mass can push the jet stream—the band of wind that typically flows from the Pacific Ocean across the U.S.—much further south as well. If the jet stream puts up a fight, the moisture it carries can fall out as heavy snow, which atmospheric scientists say is the circumstance that caused the February 2010 “snowmageddon” storm that shut down Washington, D.C.

But why does the vortex weaken? Now it gets interesting. More and more Arctic sea ice is melting during summer months. The more ice that melts, the more the Arctic Ocean warms. The ocean radiates much of that excess heat back to the atmosphere in winter, which disrupts the polar vortex. Data taken over the past decade indicate that when a lot of Arctic sea ice disappears in the summer, the vortex has a tendency to weaken over the subsequent winter, if related atmospheric conditions prevail over the northern Atlantic Ocean. The situation looks something like that shown in the graphic below. (For a full explanation, see the _Scientific American article_ that accompanies the graphic.)

Although the extent of summer sea ice in the Arctic varies year to year, overall it has been disappearing to a notable degree since 2007 and it is forecast to continue to vanish even further. That could mean more trouble for the polar vortex, and more frigid outbreaks—a seeming contradiction to “global warming,” perhaps, but not for “global weirding,” also known as climate change.


_Graphic by XNR Productions_
_Photo courtesy of Wing-Chi Poon on WikimediaCommons_


The views expressed are those of the author(s) and are not necessarily those of Scientific American. 

Mark Fischetti
Mark Fischetti is a senior editor at _Scientific American_, overseeing coverage of energy and the environment.


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## ae1905 (Jun 7, 2014)

blogs.discovermagazine.com 

*One verdict on global warming in 2017 is in: Warmest year with no temperature boost from El Niño, and second warmest overall*

This map shows how air temperatures at a height of two meters varied in 2017 from the 1981–2010 average. (Source: Copernicus Climate Change Service, ECMWF)

Today brought another lesson about the difference between weather and climate.

While winds were howling, snow was blowing, and temperatures were plummeting thanks to the bomb cyclone off the U.S. East Coast, a European science agency announced that 2017 was the second warmest year in records dating back to the 1800s. Only 2016 was warmer, according to the Copernicus Climate Change Service.

That year received a very significant temperature boost from a strong El Niño, which is characterized by high surface temperatures in the tropical Pacific Ocean. Among all years without an El Niño, 2017 was the very warmest in the Copernicus analysis.

This finding is particularly noteworthy because 2017 saw _cooling_ in the tropical Pacific from La Niña, the opposite of El Niño, both early and late in the year.

The Copernicus findings are comparable to an independent analysis done by the Japan Meteorological Agency. In coming weeks, we’ll also see analyses by NOAA, NASA, and the U.K.’s Met Office.

Over the long run, these different independent analyses have produced very similar results, as this graphic shows:

Running 60-month averages of global air temperature at a height of two metres (left-hand axis) and estimated change from the beginning of the industrial era (right-hand axis) according to different datasets: ERA-Interim (Copernicus Climate Change Service, ECMWF); GISTEMP (NASA); HadCRUT4 (Met Office Hadley Centre), NOAAGlobalTemp (NOAA); and JRA-55 (JMA).

The news released by Copernicus today— as a brutal winter storm hammers the Northeast — reminds us that human-caused global warming has not repealed winter.

*SEE ALSO: The view from space as the so-called ‘bomb cyclone’ exploded into a dangerous storm
*
That said, there has been increasing discussion among climate scientists about how long-term warming might influence major winter storms, as well as other forms of extreme weather.



Sea surface temperature anomalies in the Western Hemisphere. Note the orange and red colors.

In a nutshell, the theory goes like this: As temperatures rise more in the Arctic than in the lower latitudes, the jet stream weakens, gets more wavier, and tends to stay in this orientation for longer. This allows cold Arctic air to spill south more readily, and warm, moist air from the south to push north. When a cold, dry airmass runs into a warm, moist one, a cyclonic bomb can go off, just like the one off the East Coast. And when the clash happens over warm ocean waters, like it just did, the storm can get a moisture boost, leading to greater snowfall. In fact, sea surface waters from the Carolinas north into Canada are mostly warmer than average — in some places dramatically so.

A few important caveats are in order here: First, the jet stream theory, advanced by Rutgers climatologist Jennifer Francis and colleagues, is just that — a theory. And while evidence has been accumulating to support it, it is still a contentious area of science with many researchers not yet convinced.

Second, even if this theory offers a reasonably accurate picture of what’s going on, it would be wholly incorrect to say global warming “caused” the East Coast storm. Today, it is going by the term “bomb cyclone.” But this type of storm, known as a Nor’easter in years past, has a long and storied history. Long-term residents of the New England coast are well familiar with these damaging extreme weather events.

Over time, will events like this become stronger as the world warms? Possibly, scientists say. And then there’s the question of how much stronger.
The bottom line is that this is an area of active inquiry. And we just don’t have all the answers.

But this much is clear: The world is warming, humans are primarily to blame, and the trend has reached new heights in the past few years.


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## crazitaco (Apr 9, 2010)

So global warming means we'll finally start getting snow in the south? Hell yeah.


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## ae1905 (Jun 7, 2014)

slate.com *

Why it’s so hard to accurately predict snowfall.*

By Geoff Fox

[HR][/HR] *We’ve gotten better, but there are still a lot of calculations at play.*








Mackenzie Weber measures 25 inches of snow on furniture on her family's deck on May 18 in Nederland, Colorado. Helen H. Richardson/The_ Denver Post_ via Getty Images

How much is it going to snow Thursday? As a meteorologist, the bane of my existence is predicting snow. It is the most difficult forecast I make with dozens of different ways it can go wrong. More troubling, it’s probably the forecast most scrutinized before and after the fact.

But why? What is it about snow that makes it so tough to pin down?

Though temperatures at ground level are important, the critical numbers for assessing snowfall are much higher up in the atmosphere. We’re looking for ice crystal growth, which happens when the air is wet enough and cold enough—sometimes down to -20° Fahrenheit, though the biggest snow growth happens at somewhat warmer temperatures.

The ice crystals start small, but as they collide, they grow, until finally they’re large enough and heavy enough to fall to Earth. Snow is water plus air—air being very important. It’s the fluff factor, the reason an inch of water can be 5 inches of snow or 30 inches or something in between. The snow liquid ratio, or SLR, is different for every storm (high SLRs are good for skiing, bad for snowballs). And that’s what we’re trying to predict—how much liquid is going to produce how much snow.

Most snowstorms are driven by low pressure systems hundreds of miles across. Around the low, warm air rises and cools. That causes water vapor in the air to condense and form clouds. Liquid droplets come next until gravity and temperature begin to dominate. For those who live in snow belts there’s a second method to produce snow, the lake effect. Assessing these two methods of snow production should allow you to get a good idea of how much snow to expect, but often your final estimate is really the combination of two estimates.

The process is very exacting, intricate even. When temperatures are cold enough and the wind properly aligned through the atmosphere, lake effect snow produces narrow bands of intense snow that are extremely hard to predict. For example, I drove from Buffalo, New York, to Erie, Pennsylvania, one winter’s day. Downtown Buffalo had flurries, but as I headed into the “Southtowns,” conditions became dicey. The snow rate was a few inches an hour. And then, a few miles later along Lake Erie’s shore, the snow stopped, clouds parted, and the sun came out. My trip back saw the exact same conditions in the exact same places. Nothing had moved.

Marquette, Michigan, is a good example of how this makes forecasting more difficult. Not only does Marquette get your run-of-the-mill winter storms, it also gets lake effect snow. Lake effect there has an SLR in the 30 to 40:1 range, meaning that one inch of liquid equals 30–40 inches of snow. The larger storms that pass through are 10 to 15:1. Figuring out how this hybrid storm is going to combine includes a lot of room for error. Luckily, Marquette averages around 17 feet of snow per year—lots of time to practice.

So we forecast the amount of water, then how that water will act as it drops. Most of the time the atmosphere warms as the flakes fall … but not always. What starts in the clouds as snow can fall as sleet, rain, freezing rain, or even graupel (snowflakes pocked with rime ice). The form it falls in obviously changes how much snow ends up on the ground.

When and how you measure snow affects the final total, too. Officially it’s measured off the ground on a “snow board,” usually a large piece of plywood. Snowflakes fill gaps in the snow pile as they fall. Measuring every hour, without giving the snow time to settle will give a higher amount than measuring every six.

Over the years forecasts have improved. There are fewer busts. One reason we’ve gotten better is through improved computer modeling: We can now look at the atmosphere a little more finely. The grid points and time steps are closer together. The mathematical integration of physics is better honed.

Your mileage may vary, but accumulation amounts now have real-world usefulness. I couldn’t always say that. I still hate forecasting it, though.

*And is it ever going to end?*








The forecast map for Friday. NOAA

If you’re east of the Mississippi, you’ve probably noticed it’s been pretty cold outside. Boston hasn’t seen anything above 30 degrees Fahrenheit since Christmas. It isn’t much better in New York City, where temps above 30 degrees have been MIA since Dec. 26.

The cold has penetrated all the way to the Gulf of Mexico. A hard freeze earlier this week blasted across much of south central Texas. Tallahassee, Florida, had itself a winter storm warning and even got a little snow.


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## HAL (May 10, 2014)

The polar vortex can push (through) the jet stream..?

WTF is this utter nonsense.

The waves in the jet stream are called Rossby waves. They're a result of rotational momentum being conserved as circumferential air flows around Earth move from the equator to the poles. The momentum has to go somewhere so the jet stream basically takes a concertina shape.










Note that the red colouring there represents speed, not temperature. It results in this:










North of the jet stream is arctic air, south of the jet stream is mid-tropical air. No air is 'pushed through'.

Global warming means the transfer of energy from the equator to the poles is greater, which means the size of the Rossby waves in the jet stream are greater. It means the phenomena in the above diagram become more common and/or more extreme. This is what causes colder air to make it further south.

I learned all this in advanced geophysical dynamics classes in my final year of university.

The article in the OP reads like the non-physics-non-maths-based opinions of a (scoff scoff fnar fnar) _geography_ student.


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## ae1905 (Jun 7, 2014)

scientificamerican.com*
Humans Did Not Cause the US Cold Snap*
Scott Waldman,ClimateWire

The cold snap that sent temperatures plunging last week and brought the most frigid new year in recorded history, in some places, had nothing to do with climate change, according to a new study.

In recent years, climate scientists have studied the connection between global warming and freezing temperatures. They are examining how shifting air patterns over the Arctic, and their incursion into North America and Europe, are connected to climate change.

But the two-week deep freeze didn't carry the hallmarks of human activity, according to a rapid attribution study from Climate Central, a science communication project based in Princeton, N.J. World Weather Attribution, a group of international researchers, performed the analysis.

Temperatures in some parts of the country, including Buffalo and Detroit, were more than 20 degrees Fahrenheit below normal for this time of year. Such events are increasingly rare, and the group found that wintertime temperatures are actually increasing in the United States. That is to be expected in a warmer world, the authors wrote.

"We conclude that this was an exceptional two-week cold wave in the area in the current climate," the authors wrote. "Cold outbreaks like this are getting warmer (less frequent) due to global warming, but cold waves still occur somewhere in North America almost every winter."

That didn't stop politicians from seizing on the cold. President Trump tweeted that the East Coast "could use a little bit of that good old Global Warming," while former Vice President Al Gore tweeted that the bitter cold is "exactly what we should expect from the climate crisis."

Researchers found that such a cold spell was more likely before human-caused global warming. Now, a two-week deep freeze is about 15 times less likely to occur than a century ago, when temperatures in such an event would be 4 degrees lower, according to the international group of researchers. The cold streak was also unique in that it occurred so early in the season.

The group has looked at other extreme weather events. It found that the likelihood of Hurricane Harvey's rainfall was increased by climate change, but a drought in Somalia, in 2016 and 2017, was not connected to global warming.

There is evidence that Arctic blasts of frigid air could become more common as a result of climate change, though scientists say more study is needed to firmly draw any conclusions. That's because the jet stream around the Arctic region seems to be weakening. It typically traps and encircles the coldest air over the Arctic, but as it weakens, colder air can filter down to lower latitudes.

Scientists are looking at the link between the loss of Arctic sea ice and how it affects weather in lower latitudes, but more research is needed.

Gabriel Vecchi, a geosciences professor at the Princeton Environmental Institute and an author of the report, said the climate community is divided on whether or not colder winter temperatures can be traced to global warming. He said most experts in the field likely don't agree with that hypothesis, though he says there is evidence for it.

"The finding that cold spells could become more common due to global warming is an interesting one, but it is also a controversial one in our field," Vecchi said. "There is a lot of discussion about it in the scientific literature, and I think it's a very counterintuitive hypothesis that people have, and I think because of that, it's appealing. But we don't find any support for it in this work."

While the report failed to find human fingerprints on the cold weather, that doesn't raise questions about the broader role that people are having on the globe, he said.

"I think it would be misguided to look at any cold event as evidence for or against global warming," Vecchi said. "There is evidence for global warming on a number of levels, and the planet has been warming, the oceans have been taking up heat, sea levels have been rising, land snow has been melting, glaciers are melting, and all these other things, so the reality of global warming is uncontroversial."

Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.


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## ae1905 (Jun 7, 2014)

HAL said:


> The polar vortex can push (through) the jet stream..?
> 
> WTF is this utter nonsense.
> 
> ...


no, not "through"



> The polar vortex is a prevailing wind pattern that circles the Arctic, flowing from west to east all the way around the Earth. It normally keeps extremely cold air bottled up toward the North Pole. Occasionally, though, the vortex weakens, allowing the cold air to pour down across Canada into the U.S., or down into other regions such Eastern Europe. In addition to bringing cold,* the air mass can push the jet stream—the band of wind that typically flows from the Pacific Ocean across the U.S.—much further south* as well.



ie, it diverts the jet stream farther south


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## chad86tsi (Dec 27, 2016)

When I was a kid (1980's), we just called these "storms". Now they need new scary names.

Back then I was also told the enlarging Ozone hole was going to mean we'd all be wearing sunscreen and special glasses by the year 2020 just to go get the mail. It was believed it would accelerate.

I was also told we were entering the next ice age and to prepare for a global epidemic by 2020. It's apparent on that temperature graph from your linked scale from 1940 to 1980.

I'm no global warming denier, but I don't put a lot of faith into weather-science predictions.


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## HAL (May 10, 2014)

ae1905 said:


> > *In addition to bringing cold, the air mass can push the jet stream—the band of wind that typically flows from the Pacific Ocean across the U.S.—much further south as well.*
> 
> 
> 
> ...


No it does not push, divert or apply any force whatsoever to the jet stream, this is completely wrong. 

For a start, cold air regions are at lower pressure and, being further north, they have lower absolute vorticity, meaning they have absolutely no inclination or ability to push southwards.

Rossby waves are the one and only cause. I already explained how. The absolute vorticity link I gave above even mentions Rossby waves and their direct relation to numerical weather forecasting.

The article is wrong. You don't need to get defensive, you didn't write it.




chad86tsi said:


> When I was a kid (1980's), we just called these "storms". Now they need new scary names.
> 
> Back then I was also told the enlarging Ozone hole was going to mean we'd all be wearing sunscreen and special glasses by the year 2020 just to go get the mail. It was believed it would accelerate.
> 
> ...


Well you should.

Do you know why the ozone hole problem went away? Because national leaders listened to weather-science predictions all over the world and agreed to put a ban on CFCs, the chemicals which cause ozone depletion. This year it was finally reported that the ban was having a positive effect - the ozone hole is shrinking. That's why you haven't seen any hint of the doomsday scenario that was predicted.


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## ae1905 (Jun 7, 2014)

HAL said:


> No it does not push, divert or apply any force whatsoever to the jet stream, this is completely wrong.
> 
> For a start, cold air regions are at lower pressure and, being further north, they have lower absolute vorticity, meaning they have absolutely no inclination or ability to push southwards.
> 
> ...



I wasn't being "defensive"

I simply pointed out your error; the article didn't claim the cold polar air pushed "through" the jet stream, as you asserted:




HAL said:


> The polar vortex can push (through) the jet stream..?
> 
> WTF is this utter nonsense.



and your article didn't mention the polar vortex

what it showed is that the vortex remains intact even as the jet stream meanders south, viz



>



note the streamlines of the vortex that don't divert down into the trough of the jet stream


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## ae1905 (Jun 7, 2014)

HAL said:


> For a start, cold air regions are at lower pressure and, being further north, they have lower absolute vorticity, meaning they have absolutely no inclination or ability to push southwards.
> 
> Rossby waves are the one and only cause. I already explained how.



the polar vortex lies in the upper atmosphere _above _the cold polar air which lies along the earth's surface...it creates a low pressure zone that acts to contain the frigid air in the poles...when the vortex weakens, the pressure increases allowing the cold air to escape south..._where _it moves is probably influenced by the low pressure troughs of the rossby waves, but the waves themselves don't cause the cold snaps


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## ae1905 (Jun 7, 2014)

HAL said:


> The polar vortex can push (through) the jet stream..?
> 
> WTF is this utter nonsense....
> 
> ...



the op is based on recent research findings:



> http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-16-0259.1 *
> 
> 
> 
> ...


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## HAL (May 10, 2014)

ae1905 said:


> the polar vortex lies in the upper atmosphere _above _the cold polar air which lies along the earth's surface...it creates a low pressure zone that acts to contain the frigid air in the poles...when the vortex weakens, the pressure increases allowing the cold air to escape south..._where _it moves is probably influenced by the low pressure troughs of the rossby waves, but the waves themselves don't cause the cold snaps


Why are you pretending to know everything about a topic from a random article you posted on a web forum. I'm telling you right now with absolute certainty, Rossby waves are the one and only thing that allow cold air to head further south. Without that phenomenon, North America and Europe would have steady weather all year round.



ae1905 said:


> the op is based on recent research findings:


And? The research abstract looks fine. But your article said this:



ae1905 said:


> > In addition to bringing cold, *the air mass can push the jet stream*—the band of wind that typically flows from the Pacific Ocean across the U.S.—much further south as well.


which is wrong.

Rossby wave amplitude will surely change because the energy gradient changes between the hot air and cold air which is released from a weak polar vortex. But nothing is being pushed anywhere. It doesn't work like that.



ae1905 said:


> I wasn't being "defensive"


You are definitely being defensive of a questionably worded pop science article you that you didn't write.


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## ae1905 (Jun 7, 2014)

HAL said:


> Why are you pretending to know everything about a topic from a random article you posted on a web forum.


I'm not pretending to know everything about a topic I post...I'm simply pointing out the error of your claim




> I'm telling you right now with absolute certainty, *Rossby waves are the one and only thing that allow cold air to head further south*. Without that phenomenon, North America and Europe would have steady weather all year round.


if rossby waves were the "only mechanism"--as you wrongly claim--outbreaks of polar air would happen _routinely_, since these waves are _always _present

the point of the op is that it is the _variability of the polar vortex--_caused, it is believed, by the melting of the ice cap--that produces cold snaps, not rossby waves 




> And? The research abstract looks fine. But your article said this:
> 
> which is wrong.



first, the abstract said this:



> The extra-tropical stratosphere in boreal winter is characterized by a strong circumpolar westerly jet, *confining the coldest temperatures at high latitudes*. The jet, referred to as the _stratospheric polar vortex_, is predominantly zonal and centered around the pole; however, it does exhibit large variability in wind speed and location. Previous studies showed that a *weak stratospheric polar vortex can lead to cold-air outbreaks in the mid-latitudes* but the exact relationships and mechanisms are unclear.



there is no mention of rossby waves, only the polar vortex


second, winds are large air masses that move from high pressure to low pressure zones...air in low pressure zones are literally _pushed out _by incoming air from high pressure zones

_F=ma_

newton's law works in the atmosphere, too


(and, yes, I understand that winds are also infuenced by the coriolis force)





> Rossby wave amplitude will surely change because the energy gradient changes between the hot air and cold air which is released from a weak polar vortex. But nothing is being pushed anywhere. It doesn't work like that.



yeah, it does....cold polar air pushes south, displacing warmer air...this colder air sitting farther sourth in turn changes where convection cells lie...since the jet stream arises from the circulation of these cells, the stream is literally _pushed _south by the incoming polar air




> You are definitely being defensive of a questionably worded pop science article you that you didn't write.


the op is based on the scientific research I linked above

what I question is your understanding of undergraduate physics


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## HAL (May 10, 2014)

ae1905 said:


> what I question is your understanding of undergraduate physics



Ha, politely fuck off.

You are completely wrong. How do I know?

Because you said this:



> I'm not pretending to know everything


and then you said this:



> second, winds are large air masses that move from high pressure to low pressure zones...air in low pressure zones are literally _pushed out _by incoming air from high pressure zones
> 
> _F=ma_
> 
> newton's law works in the atmosphere, too


You are wrong and don't be so condescending you cunt. F=ma? What you need is this one and don't pretend you know what you're looking at because I know you don't.


Pressure variation is the primary cause of air flow but only on a very very largescale, i.e. global air convection from equator to the poles. Once the coriolis force kicks in, winds in fact go _around_ areas of pressure. It's a phenomenon called geostrophic balance. Don't pretend you knew that. You didn't.





> undergraduate physics


Not all physics courses are the same. I sat through advanced fluid mechanics and geophysical fluid mechanics courses that the vast majority of institutions do not offer. Stop pretending to know about these subjects and don't ever try to say my understanding is wrong. I may well be incorrect about some things, for sure, but you would never even know. You don't know enough about the subject.



> the point of the op is that it is the variability of the polar vortex--caused, it is believed, by the melting of the ice cap--that produces cold snaps, not rossby waves


No, the point is that a weaker polar vortex lets some cold air further south than normal, which is then further released by large rossby waves. But this is already common knowledge. The article simply made comments on what causes the polar vortex to weaken in the first place - melting ice caps - and then the author claimed the air pushes the jet stream further south which is wrong.

Many people even with full physics degrees are of the same opinion as you, believing pressure is the main driver of wind direction. It isn't. Geostrophic balance sees to that. Most physics students don't learn about the principles of fluid dynamics on rotating reference frames. Hell, a large amount of students don't learn any fluid dynamics at all. In fact a lot of physics student don't even learn about the _basic_ mechanics of rotating frames.

All of this is advanced stuff that the disinterested student can avoid if they prefer other areas of physics. For example, I have no idea about astrophysics, I have no idea beyond the basics of condensed matter physics, and I can barely tell you anything other than the basics of special relativity. These aren't my areas. Physics is a huge discipline. I chose advanced mechanics and fluid dynamics as my more specialist areas of study. I can safely say I know more than most physics graduates on these topics.

I wrote my final project on a very similar topic and got a top grade for it. It may even be published in a journal soon. Stop trying to outsmart me on this stuff.


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## ae1905 (Jun 7, 2014)

HAL said:


> Ha, politely fuck off.
> 
> You are completely wrong. How do I know?
> 
> ...



knowing a few things =/= "knowing everything"


guess they didn't teach you basic logic in that fluid dynamics course


pity




> Don't be so condescending you cunt. F=ma? What you need is this one and don't pretend you know what you're looking at because I know you don't.



navier-stokes _*IS *_F=ma!

LOLOLOLOLOLOLOLOLOL





> Pressure variation is the primary cause of air flow but only on a very very largescale, i.e. global air convection from equator to the poles. Once the coriolis force kicks in, winds in fact go _around_ areas of pressure. It's a phenomenon called geostrophic balance. Don't pretend you knew that. You didn't.


actually, I did know that...I've seen weather maps showing high and low pressure zones

and winds *do *flow from high to low pressure zones...a pressure zone is not a single point on a map....it's a _region _of high or low pressure...air masses move between these regions




> Not all physics courses are the same. I sat through advanced fluid mechanics and geophysical fluid mechanics courses that the vast majority of institutions do not offer. Stop pretending to know about these subjects and don't ever try to say my understanding is wrong. You have no idea about this.



you are wrong

rossby waves don't cause cold snaps


just admit your understanding is flawed, intp




> No, the point is that a weaker polar vortex lets some cold air further south than normal, which is then further released by large rossby waves. But this is already common knowledge. The article simply made comments on what causes the polar vortex to weaken in the first place - melting ice caps.



no

the cold air mass pushes the mid-latitude convection cell farther south, thereby pushing the jet stream farther south

you can see the effect of cold weather on the jet stream in this figure:











this is common knowledge


so it is common knowledge that you are wrong


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## ae1905 (Jun 7, 2014)

HAL said:


> Many people even with full physics degrees are of the same opinion as you, believing pressure is the main driver of wind direction. It isn't. Geostrophic balance sees to that. Most physics students don't learn about the principles of fluid dynamics on rotating reference frames. Hell, a large amount of students don't learn any fluid dynamics at all.
> 
> I wrote my final project on a very similar topic and got a top grade for it. It may even be published in a journal soon. Don't tell me I don't know about this stuff.



I said that wind is the motion of air masses caused by pressure gradients AND the coriolis force


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## HAL (May 10, 2014)

ae1905 said:


> rossby waves don't cause cold snaps


No they do not 'cause' them, but they absolutely bring them down to the population areas of North America and Europe. Without rossby waves you would never have any cold air making its way further south than the average circumferential route that the jet stream takes. Waves in the jet stream are caused by energy variation. This is probably linked to the cold air, but not by a basic 'pushing' mechanism that you are attempting to describe. The cold air cannot merrily push something as leviathan as the jet stream. 



> I said that wind is the motion of air masses caused by pressure gradients AND the coriolis force


Yes, everyone knows the fun little coriolis fact that winds are driven in a latitudinal direction due to coriolis forces. But no you absolutely did not know that geostrophic balance causes wind to go around high and low pressure zones.

You make this claim:



> and winds do flow from high to low pressure zones...a pressure zone is not a single point on a map....it's a region of high or low pressure...air masses move between these regions


but just look at any weather map and you'll see how absolutely wrong you are. Here are some examples:


















Look at all those pressure isobars, and look at how the wind goes _along_ the isobars. That means the wind is going _around_ pressure regions. There is no movement into or out of higher or lower pressure. This is geostrophic balance and it's what dictates wind direction. It has nothing to do with pressure at this scale. You can see clear as day where the wind is going, and it is most certainly not doing what you described.



> this is common knowledge
> 
> 
> so it is common knowledge that you are wrong


I give up.

This is the third time you and I have ended up in a discussion where you desperately attempt to show working knowledge in an area you know no more than the amateur enthusiast.


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## ae1905 (Jun 7, 2014)

HAL said:


> No they do not 'cause' them, but they absolutely bring them down to the population areas of North America and Europe. Without rossby waves you would never have any cold air making its way further south than the average circumferential route that the jet stream takes.



no, you're wrong (as usual)

rossby waves wouldn't exist if the earth didn't rotate...however, atmospheric circulation of air induced by differential solar heating would still happen and would carry cold air from the poles towards the equator--ie, there would be one large convection cell in each hemisphere




> Waves in the jet stream are *caused *by energy variation. This is probably linked to the cold air, but not by a basic 'pushing' mechanism that you are attempting to describe.



this is a red herring...the op didn't claim the cold air "creates" rossby waves




> The cold air cannot merrily push something as leviathan as the jet stream.



yeah, it can...and it does

the jet stream follows the boundary between the polar and mid-latitude convection cells...cold polar air pushes this boundary farther south, carrying the jet stream with it

put in your terms, colder air _is _the "energy variation" that causes the jet stream to move farther south in the same way the colder winter north american landmass causes the jet stream to divert farther south





> Yes, everyone knows the fun little coriolis fact that winds are driven in a latitudinal direction due to coriolis forces. But no you absolutely did not know that geostrophic balance causes wind to go around high and low pressure zones.



yeah, I did

fluid streamlines can't terminate at a point unless it is a source or sink

you don't need a degree in physics to know that




> You make this claim:
> 
> but just look at any weather map and you'll see how absolutely wrong you are. Here are some examples:
> 
> ...



in the first figure, the streamlines flow towards the low pressure zone from a high pressure zone which is not shown...some of this air is entrained in the vortex of the low pressure zone where it spirals inwards towards the center (where it is pushed up into the atmosphere above)

so some of the air from high pressure zones does, in fact, get sucked into the center of the low pressure zone 




> I give up.
> 
> This is the third time you and I have ended up in a discussion where you desperately attempt to show working knowledge in an area you know no more than the amateur enthusiast.



yes, and I schooled you every other time I interacted with you just as I schooled you here


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## ae1905 (Jun 7, 2014)

@HAL


I created the following thread for people like you

http://personalitycafe.com/member-p...changed-your-mind-after-debate-here-perc.html


feel free to explain why you slink away


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## chad86tsi (Dec 27, 2016)

ae1905 said:


> and, yes, you've made my point...you seem to have a thing for the idea, "high to low", so much so, you've made me repeat it again and again!


but there is evidence that this high to low theory is oversimplified observation. It doesn't explain as behaviors that are observable and documented. It's a variable among many. It misses other important factors.




ae1905 said:


> is that how you figured the storm came from nevada, infp?


I was using your established logical process of high to low. It didn't predict reality.



ae1905 said:


> winds traveling north and east can't originate in nevada if their destiny is oregon


the pressure difference existed between Northwest and Southeast. The system traveled perpendicular to that angle. You say pressure/mass/force changes high to low. that is not the only thing it does though.

you have one force moving west to east, and another south to north. when they interact, you end up with a deflected "sum" trajectory that is at about 45* to both (Southwest to Northeast). You only discuss one of those forces, and don't explain the deflection.



ae1905 said:


> it's you who imagines I think it somehow "proves" it


No, I never said that. you are projecting. 



ae1905 said:


> when the storm system arrives it displaces the dry air that was there a day or two before
> 
> so the fact the air was dry yesterday doesn't mean it will be dry when the storm begins
> 
> see why I laughed now?


The only high within 1000 miles was Nevada, so I'm not sure what other high you believe was the cause. You seem to indicate somewhere near the 30* latitude but it's not present in the provided pressure map (which extends to about 15*). If you are saying there is an unseen high further to the west, it clearly didn't flow into the low as you sate it must.



ae1905 said:


> you're wasting my time, now
> 
> you don't have the smarts to spar with me


That says more about you than I think you realize. Good luck.


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## HAL (May 10, 2014)

This thread is fucking hilarious.

Desperate boy on the internet who thinks he knows what he's talking about, being schooled by a person with rigorous educational background on the subject, and someone with rigorous direct observational knowledge on the subject.

Fucking hilarious.

Fight the good fight, young man.

I am genuinely utterly stunned by the continous blind arrogance that has been displayed here, not to mention the sheer dickheadery in every response.



> "LOLOLOLOL, intp, infp, LOLOLOLOLOL"


You have a lot of growing up to do.


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## HAL (May 10, 2014)

chad86tsi said:


> ae1905 said:
> 
> 
> > you're wasting my time, now
> ...


Indeed it does, very much so.

I like to think he'll someday go out into the world and learn to be an adult.

This thread is done for me now. It's going round in circles.


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## HAL (May 10, 2014)

Actually fuck it I'll bite a little bit.
@ae1905

You claim that deep ocean water is different to surface water, and you claim that this somehow makes you correct. This is bollocks. I told you that wind drag is the primary cause of almost all water movement in the oceans. You then stated I was wrong, claiming the majority of movement is in the deep oceans. You were wrong and I showed you this with abundant evidence. You can't skirt around this, stop being so childish and accept you were utterly wrong.

Secondly this:



ae1905 said:


> also, the maps cited here give a eulerian picture of the flow field, that is, velocities at different _points _in space and time...this doesn't necessarily describe the _paths _of individual parcels of air, however...for this, you need to map the lagrangian flow field, viz, the velocities of _individual parcels_ of air as _they _move through space and time...if you did this, you would find that parcel paths deviate from isobars, especially close to land and in convergence and divergence zones
> 
> 
> https://en.wikipedia.org/wiki/Lagrangian_and_Eulerian_specification_of_the_flow_field



is hilarious. Well done, you googled something about continuum mechanics. I learned this in the first week of my first ever fluid dynamics course, haha.



> if you did this, you would find that parcel paths deviate from isobars


No, you have completely made up this statement. The only thing that would make the path deviate is if the pressure force becomes immensely greater than the coriolis force. This may indeed happen at times. But the opposite is also equally if not _more_ likely - the coriolis force can move air _away_ from low pressure zones. The jet stream is a wonderful example of this. Another good example is the countless hurricanes you've been discussing with @chad86tsi, where intense low pressure systems make their way for thousands of miles across to the US coast as air swirls violently _around_ them... not directly into them.

For the case of the weather maps, if you want to see how the flows change with time, look at the below examples, particularly the right hand images because they're more clear:


























Ta-daaa, always following isobars.

What this also shows is how pressure does play a role in guiding wind motion. You can see that the wind flow goes where the pressure regions go. This is what I conceded before several pages ago. However, it goes _around_ the pressure, not into or out of it.

Unfortunately you are solely obsessed with the idea of wind going from high to low pressure zones which is wrong in all the cases we've looked at. You just don't know enough about fluid dynamics on rotating frames. But that's fine, most people don't.

I wish you were more open to learning things, instead of stubbornly claiming to know everything after a bit of furious wikipedia reading. I've conceded points where I was mistaken. Why can't you?


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## Maybe (Sep 10, 2016)

*Thread Warning
Do not insult/attack/troll others.


Please take a moment to review the rules:*


> *1. Do Not Make Personal Attacks*
> Posts that serve no purpose other than to flame and attack other users annihilate the quality of discussion. You may critique or disdain argument and opinion posted by users, but you may not extend that method to maligning the users themselves. Do not harass or bully other members, which includes the following:
> - "type-bullying," which we define as the persistent and unsolicited public questioning of another member's type when they have not expressed such an interest.
> - purposefully misgendering other members from the identification they have chosen on their profile.
> ...


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## ae1905 (Jun 7, 2014)

HAL said:


> Actually fuck it I'll bite a little bit.
> @*ae1905*
> 
> You claim that deep ocean water is different to surface water, and you claim that this somehow makes you correct.



so your position is wind drag causes deep water currents, hal?




> This is bollocks.



I couldn't have said it better myself






> I told you that wind drag is the primary cause of almost all water movement in the oceans. You then stated I was wrong, claiming the majority of movement is in the deep oceans.



wrong, hal

I said wind drag only affects the surface layer of the ocean


do you know what the surface layer is, hal


you should because your understanding of fluid dynamics is superficial




> You were wrong and I showed you this with abundant evidence. You can't skirt around this, stop being so childish and accept you were utterly wrong.



I was right, hal


wind drag only acts on the ocean's surface layer




> Secondly this:
> 
> is hilarious. Well done, you googled something about continuum mechanics. I learned this in the first week of my first ever fluid dynamics course, haha.
> 
> ...



what are these convergence zones, then, hal?




> *Convergence zone*
> 
> From Wikipedia, the free encyclopedia
> 
> ...



"vertical movement" in "low pressure areas"

when winds are pushed _up _into the sky in low pressure zones, what happens to the relative _vacuum _created on the surface below, hal?

according to you, why isn't surrounding surface air drawn into this void?




> Unfortunately you are solely obsessed with the idea of wind going from high to low pressure zones which is wrong in all the cases we've looked at. You just don't know enough about fluid dynamics on rotating frames. But that's fine, most people don't.
> 
> I wish you were more open to learning things, instead of stubbornly claiming to know everything after a bit of furious wikipedia reading. I've conceded points where I was mistaken. Why can't you?



I am open to learning things, hal, but you have nothing to teach

you don't even understand that geostrphic _balance _means a balance between pressure and coriolis forces or the jet stream is caused (in part) by the interaction between large-scale convection cells!

and you don't understand the difference between eulerian and lagrangian descriptions of flow:



> Well done, you googled something about continuum mechanics. I learned this in the first week of my first ever fluid dynamics course, haha.
> 
> No, you have completely made up this statement. The only thing that would make the path deviate is if the pressure force becomes immensely greater than the coriolis force.



all the maps you have posted show eulerian flow fields, that is, they show wind velocities at _fixed points_ in space...over time, different air parcels pass through these fixed points so any one map or even a series of maps will not necessarily show the paths of _actual _air parcels

consider this simple fact...isobars are lines on _two dimensional maps_ of constant pressure...two-dimensional maps show information at a single elevation only...in particular, they don't capture the _vertical component_ of velocity...unless you believe air never moves up or down but always remains at the same elevation, you will recognize that these maps fail to capture the paths of _actual air parcels_*...so looking at one or two 2-D maps and imagining winds travel along isobars in a single plane is a simplification anyone with any experience of winds will find questionable

2-dimensional eulerian flow fields are _not _the same as 3-dimensional lagrangian flow fields for complex flows such as weather systems

note: you probably don't know this but static pressure varies directly with elevation so any motion_ out of the plane _of the 2-D map crosses the isobars

* fluid _turbulence, _which is usually present for flows on these scales, causes vertical (and in plane) momentum transport


but that isn't the only difference between eulerian and lagrangian descriptions of flow...even if we suppose winds are confined to a single elevation, the eulerian flow field will still not describe the paths of individual air parcels when the flow is _unsteady_, that is, when the eulerian velocities change with time...so to interpret the 2-D maps as fluid _pathlines _you have to assume one map describes the entire flow field _for all time!_...(well, maybe not _all time _but certainly for _all the time in question_)...this is patently untrue...winds vary almost continuously in speed and direction, even at fixed locations


so the _time variability _of wind patterns is another reason 2-D eulerian maps cannot simply be interpreted even as 2-D lagrangian descriptions of flow, much less 3-D descriptions


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## ae1905 (Jun 7, 2014)

the pineapple express:



wiki said:


> *Pineapple Express events*
> 
> Main article: Pineapple Express
> 
> ...



the pineapple express is a particular type of storm system...it is unusual in that the moisture comes mainly from the _tropics_, from the MJO storm system that travels from the indian ocean to the central pacific (dark gray clouds in the figures above)...some of this moist air, however, crosses the boundary between the hadley and mid-latutude cells and is pushed by divergent winds north and east towards and past hawaii (green patches in the figures above)...these are the large-scale northeast surface winds of the mid-latitude cell...this coupling between the MJO storm and the moisture plumes creates a so-called _atmospheric river_ that feeds the storms on the north american westcoast _when a low pressure system develops there_

so, yes, the moisture comes from the ocean south and west of north america (in this case, from the tropics)...but the low pressure zone over the pacific northwest develops _there_, not in hawaii


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## chad86tsi (Dec 27, 2016)

ae1905 said:


> the jet stream doesn't carry the pineapple express...the express are surface winds...the jet stream lies in the upper atmosphere, far above the pineapple


From your article (which is the same one I referred to yesterday):

The typical scenario linking the pattern of tropical rainfall associated with the MJO to extreme precipitation events in the Pacific Northwest features a progressive (i.e. eastward moving) circulation pattern in the tropics and a retrograding (i.e. westward moving) circulation pattern in the mid latitudes of the North Pacific. Typical wintertime weather anomalies preceding heavy precipitation events in the Pacific Northwest are as follows:[13]


7–10 days prior to the heavy precipitation event: Heavy tropical rainfall associated with the MJO shifts eastward from the eastern Indian Ocean to the western tropical Pacific. A moisture plume extends northeastward from the western tropical Pacific towards the general vicinity of the Hawaiian Islands.* A strong blocking anticyclone is located in the Gulf of Alaska with a strong polar jet stream around its northern flank.*[13]
3–5 days prior to the heavy precipitation event: Heavy tropical rainfall shifts eastward towards the date line and begins to diminish. The associated moisture plume extends further to the northeast, often traversing the Hawaiian Islands. The strong blocking high weakens and shifts westward. *A split in the North Pacific jet stream develops, characterized by an increase in the amplitude and areal extent of the upper tropospheric westerly zonal winds on the southern flank of the block and a decrease on its northern flank. The tropical and extra tropical circulation patterns begin to "phase", allowing a developing mid latitude trough to tap the moisture plume extending from the deep tropics.*[13]
The heavy precipitation event: As the pattern of enhanced tropical rainfall continues to shift further to the east and weaken, the deep tropical moisture plume extends from the subtropical central Pacific into the mid latitude trough now located off the west coast of North America. *The jet stream at upper levels extends across the North Pacific with the mean jet position entering North America in the northwestern United States.* _The deep low pressure located near the Pacific Northwest coast can bring up to several days of heavy rain and possible flooding_. These events are often referred to as Pineapple Express events, so named because a significant amount of the deep tropical moisture traverses the Hawaiian Islands on its way towards western North America.[13]


So Yes, it does. 

The low concentrates and "aims" it, and causes it to dump it's moisture as I said yesterday.

It's pretty good evidence of how the lower atmosphere and Troposphere can interact.


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## ae1905 (Jun 7, 2014)

chad86tsi said:


> From your article (which is the same one I referred to yesterday):
> 
> The typical scenario linking the pattern of tropical rainfall associated with the MJO to extreme precipitation events in the Pacific Northwest features a progressive (i.e. eastward moving) circulation pattern in the tropics and a retrograding (i.e. westward moving) circulation pattern in the mid latitudes of the North Pacific. Typical wintertime weather anomalies preceding heavy precipitation events in the Pacific Northwest are as follows:[13]
> 
> ...



as I said, infp, the jet stream can't _carry _the pineapple express because the jet flows in the upper atmosphere above the moisture plume which sits on the ocean surface

the jet is the product of the interaction of the mid-latitude and polar cells...in winter this boundary dips south across the pacific creating a band of low pressure...moist air from the tropics is pushed towards this band by the northeast surface winds of the mid-latitude cell...because the low pressure system formed over washington and oregon is stronger (lower pressure), the moist air flows towards north america along the band (it is also driven east by the moving mjo storm system feeding it from the tropics)

the jet stream happens to lie above the band of low pressure the moist air follows...it isn't "carrying" the moist air far below


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## chad86tsi (Dec 27, 2016)

And gas doesn't "carry" you to your destination, but you car won't run without it. The jet doesn't carry moisture, but it creates the trough, and gives it a direction to travel.

A split in the North Pacific jet stream develops, characterized by an increase in the amplitude and areal extent of the upper tropospheric westerly zonal winds on the southern flank of the block and a decrease on its northern flank. The tropical and extra tropical circulation patterns begin to "phase", allowing a developing mid latitude trough to tap the moisture plume extending from the deep tropic

Which is cause, and which is effect?

Without the jet, there is no Pineapple express. This goes back to the original debates of cause and effects on the polar vortex. The interaction of upper and lower levels of the atmosphere.


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## ae1905 (Jun 7, 2014)

chad86tsi said:


> And gas doesn't "carry" you to your destination, but you car won't run without it. The jet doesn't carry moisture, but it creates the trough, and gives it a direction to travel.



no...the jet doesn't "create a trough"...the trough is created by the interaction between hot and cold air masses where they meet, in this case between the warmer air in the mid-latitude cell and the colder air in the polar cell at the boundary in the mid-latitudes...the cold surface air forces the warmer surface air up to higher altitudes...it's this _updraft _of air that creates the region of low pressure on the surface (which is filled by surface air around the low being sucked in--ie, convergent flow, hence, "convergence zone")





> A split in the North Pacific jet stream develops, characterized by an increase in the amplitude and areal extent of the upper tropospheric westerly zonal winds on the southern flank of the block and a decrease on its northern flank. The tropical and extra tropical circulation patterns begin to "phase", allowing a developing mid latitude trough to tap the moisture plume extending from the deep tropic



when the cold air diverging from the high pressure zone around alaska meets the warmer air of the moisture plume the resulting updraft I just described creates a second branch of the jet stream...this new boundary then becomes the effective boundary of the mid-latitude cell in the eastern pacific and its circulation becomes coupled to the circulation in the hadley cell where the mjo storm is, hence, the pineapple _express_




> Which is cause, and which is effect?



the jet is the product of what is happening on the surface




> Without the jet, there is no Pineapple express. This goes back to the original debates of cause and effects on the polar vortex. The interaction of upper and lower levels of the atmosphere.



the pineapple express _creates _the new branch in the jet


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## Cal (Sep 29, 2017)

@*chad86tsi*  @*HAL Why are you guys even bothering to argue with the OP? We all know that he doesn't seem to act to mature when his beliefs and understanding of things are corrected or challenged, and we all know that this argument will only end in him both denying and provoking you two.

Better off just leaving him be. I don't think he is going to bother listening anytime soon.*


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## chad86tsi (Dec 27, 2016)

Cal said:


> @*chad86tsi*  @*HAL Why are you guys even bothering to argue with the OP? We all know that he doesn't seem to act to mature when his beliefs and understanding of things are corrected or challenged, and we all know that this argument will only end in him both denying and provoking you two.
> 
> Better off just leaving him be. I don't think he is going to bother listening anytime soon.*


I guess I took his signature line seriously...


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## Cal (Sep 29, 2017)

chad86tsi said:


> I guess I took his signature line seriously...


I once found him using it to prove a point in a debate. :laughing:


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## chad86tsi (Dec 27, 2016)

ae1905 said:


> the pineapple express _creates _the new branch in the jet



The jet branches when the blocking high moves west and dissipates, then the jet undercuts it and resumes a "normal" path. This creates a trough, and the pineapple express is sucked in by that change in boundaries. Cause : Effect

It was not a pineapple express before the jet moved. The pineapple Express was formed from a diminishing western central-pacific tropical wet air mass that was drawn into that trough by phasing of the cells, and realignment alignment of the jet. The shift of the jet was caused by the shift of the blocking high. 

The low over the northwest was the last event to occur in the timeline of your article.

Even though the wind "tries" to flow from high pressure to low pressure, the turning of the Earth causes the air flow to turn, so the jet stream flows around the air masses, rather than directly from one to the other. 

I agree that the jet stream does not "cause" weather conditions to occur. Its existence is instead the result of certain conditions (a large temperature contrast between two air masses). It occurs at the boundary of contrasting temperature/pressure. To describe the boundary location is to describe the location of the jet. They are synonymous. To describe the jet is to describe the area of activity (wind/rain).



ae1905 said:


> the cold air diverging from the high pressure zone around alaska


A cold air mass coming from a high? I'm not familiar with this, unless you mean the polar jet moving south of the high.


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## ae1905 (Jun 7, 2014)

chad86tsi said:


> A cold air mass coming from a high? I'm not familiar with this, unless you mean the polar jet moving south of the high.



an anticyclone is a high pressure zone where surface flows _diverge in a clockwise _direction--ie, _opposite _to the moisture plume

now, is the air near alaska warmer or colder than the air coming from hawaii, especially in winter?

delta T, right?

get it?






> The jet branches when the blocking high moves west and dissipates, then the jet undercuts it and resumes a "normal" path. This creates a trough, and the pineapple express is sucked in by that change in boundaries. Cause : Effect



why does the high weaken?

why does it move west?

how does it split the jet stream?


and if the jet stream is "synonymous with boundaries between contrasting temperature/pressure", as you say below, what is the split jet stream the boundary of?




> It was not a pineapple express before the jet moved. The pineapple Express was formed from a diminishing western central-pacific tropical wet air mass



"diminishing"?

the mjo storm was weakening but the moisture plume was growing




> that was drawn into that trough by phasing of the cells,



no

the "diminishing tropical wet air mass" was not drawn into the trough...the mjo storm remained in the tropics


I'm curious what you imagine "phasing of the cells" means?...can you explain your understanding of the dynamics here?




> and realignment alignment of the jet. The shift of the jet was caused by the shift of the blocking high.



again, how?




> The low over the northwest was the last event to occur in the timeline of your article.
> 
> Even though the wind "tries" to flow from high pressure to low pressure, the turning of the Earth causes the air flow to turn, so the jet stream flows around the air masses, rather than directly from one to the other.



the low in the northwest forms when cold polar air moves south in the wake of the departure of the blocking high


it actually takes a strong low to produce the strongest pineapple express storms




> I agree that the jet stream does not "cause" weather conditions to occur. Its existence is instead the result of certain conditions (a large temperature contrast between two air masses). It occurs at the boundary of contrasting temperature/pressure. To describe the boundary location is to describe the location of the jet. They are synonymous. To describe the jet is to describe the area of activity (wind/rain).



agreed


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## marblecloud95 (Aug 12, 2015)

Cal said:


> I once found him using it to prove a point in a debate. :laughing:


atleast he didnt pull a Michael Scott


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## Cal (Sep 29, 2017)

marblecloud95 said:


> atleast he didn't pull a Michael Scott


what is that?


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## marblecloud95 (Aug 12, 2015)

Cal said:


> what is that?


basically quoting others and ascribing quotes to ones self


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## HAL (May 10, 2014)

@ae1905

Ever heard of Deepak Chopra?

He's a new age pseudo-scientist who is roundly criticised for using scientific jargon to sound clever, which tricks dumb audiences into thinking he knows what he's talking about, while the real science community can see clear as day that he is speaking complete and utter nonsense.

In this thread you have become like Deepak Chopra.

You're throwing around words and phrases relating to geography, physics and fluid dynamics which you clearly have barely encountered before, and are making it up as you go along, attempting to intuit their meaning and their relation to the current discussion while sounding "a little bit right" but in fact getting the vast majority of it entirely wrong.

I think what annoys me more is not that your posts are a patchwork of wrongness and rightness, it's that you just make shit up when you don't know. Your use of Eulerian and Lagrangian frames of reference in order to sound like you know what you're talking about and disprove the reliability of weather maps is a mixture of hilarious and infuriating. The two are not related in the way you believe. The Eulerian description describes the field and how the field changes. The Lagrangian description describes how a single particle will move through that field. The two are different ideas. A particle will always move in the way the vectors tell it to. If you see a weather map with wind vectors pointing a certain way... your chosen particle of air will sure as hell move where the vectors are pointing. The Lagrangian description isn't some kind of 'get out of jail free' card that lets the wind go somewhere else.

If you want to see how wind particles move, watch this video which I already showed you. It's a recording of air particles, mainly sand and moisture. There is no better example than the real world.






Once again you are proven fantastically wrong. Air drifts east and west because of the coriolis force (with no coriolis force, the primary movement would be equator-to-pole), and it swirls violently _around_ low pressure cyclonic systems, not into them.

You need to get your head out of the sand and accept your knowledge limitations. All these hand-wavy, wikipedia-backed arguments with semi-literate science jargon are just incredible to witness, and again I say your arrogance is at a whole new level. It's like me saying, "_My computer works because of all the quantum leaps in the semiconductors! The Schrodinger equation needs to be written according to the Kronig-Penney model in order to understand the band gap of the two-dimensional lattice on which conduction occurs! To solve this, we need to use Bloch's theorem on the partial differential vector calculus form of the Schrodinger wave equation!_"

I'd be a little bit right and all the big words make me sound like I know what I'm talking about, but any computer scientist worth their salt would tell me I'm talking utter gibberish in relation to the way computers _actually_ work, and that my basis is nothing but pure whataboutery using a few nifty physics terms.

This is what it sounds like when you attempt to sound correct in this thread. You're doing a Deepak Chopra.



> Chopra's "nonsensical references to quantum physics" are placed in a lineage of American religious pseudoscience, extending back through Scientology to Christian Science. Physics professor Chad Orzel has written that "to a physicist, Chopra's babble about 'energy fields' and 'congealing quantum soup' presents as utter gibberish", but that Chopra makes enough references to technical terminology to convince non-scientists that he understands physics.


Now the same quote but with reference to Personality Cafe's favourite hand-wavy pseudo-science enthusiast.



> ae1905's "nonsensical references to geophysics" are placed in a lineage of American religious pseudoscience, extending back through Scientology to Christian Science. Physics gradate Hal has written that "to a physicist, Chopra's babble about 'Eulerian and Lagrangian descriptions of flow' and 'surface winds not being relevant to ocean flow' presents as utter gibberish", but that ae1905 makes enough references to technical terminology to convince non-scientists that he understands physics.


And finally I would like to ask, for the third time: What educational or experiential credentials do you have on the topic we're discussing here? I find it telling that you haven't answered this yet.


----------

