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Messages - sark

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Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 09:35:49 PM »
ECMWF 240 hour geopotential height anomaly.  I'm not interested in arguing about 10 day forecasts, I just don't think anyone is misled by it.

Clearly we got ridge & continued northern blocking despite repeated forecasts of a diminishing event. 

Whenever there's two polar cells, the gears mesh and high pressure rips in.  Easy to predict.

Arctic sea ice / Re: The 2019 melting season
« on: July 12, 2019, 11:05:22 PM »
Will there be a tally of number of weather records broken?  It seems like a new record in 2019.

Arctic sea ice / Re: The 2019 melting season
« on: July 11, 2019, 08:17:44 AM »
Friv, that pattern change forecast by so many is turning for the worse already.  GFS has now revealed that it is expecting TWINS!

GFS 00Z 7/11 splits completely to hell throughout the whole 2 week period. 

Big ridges expected from Beringia/Scandinavia before 240 hours.

That's the Eastern US and East Atlantic. Click to run gif.  Midlats cyclone headed north up the Eastern seaboard in hour 70+

Scary storm fires up off thunderstorm activity in the GFS, hour 70-180

Arctic sea ice / Re: The 2019 melting season
« on: July 03, 2019, 04:03:44 AM »
This is a paint drip chart of Arctic geopotential height anomalies throughout the column.  Long range forecasts are still not indicating a break from this.

I think you are correct but I don't think it's exactly accurate to say the polar cell is failing -- the *single* polar cell system is now changing into a state where we have two smaller continental polar cells centered over North America and Eurasia, with increasing dominance of the NAmerican cell (IMO).

So, yes, the single-polar-cell system is failing, but we still have polar cells, they are just centered in abnormal locations and are now advecting heat into the High Arctic instead of dissipating heat entering the High Arctic (at least, advection is now occurring more often than dissipation).

Pretty much how I see it.  Except there's sort of a third polar cell going on, often over Sea of Okhotsk.

I love this video of a winter PV split

Dr Judah Cohen has published an update to the AER blog.  Forecast ensemble sees a continued cooling in upper level polar cell with continued troposphere warmth into the first weeks of July.

I was really hoping this pattern would break as soon as the snow melted of land

Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 02:33:16 PM »
I thought things were improving somewhat as the last ridge we were just watching over Greenland failed to pierce the polar front.  at least it isn't dual monster ridges coming from both East & West cutting the whole thing neatly in half as we have observed a half dozen times since November.  Now it's just one side at a time.

I'm guessing all that time the polar cell spent displaced out of the Arctic, lashing the continents with cold rain & snow... has warmed it up a big step.  The snow on land is virtually gone, and sure enough, the polar cell consolidates over the Arctic generally.

Chaos is entering the equation in a big way.  Predictability is falling.  This is a transition.

Policy and solutions / Re: A reference personal carbon budget
« on: June 11, 2019, 08:54:04 AM »
I'm skeptical of the whole concept because I've lived in that carbon budget.  It's unwelcome in society.  Any hail mary ideas

Y'all can go on about it being open if you want - me, I'm gonna keep on paddlin' to Prince Patrick Island.

Plant some Cycads and Citrus trees

Policy and solutions / Re: A reference personal carbon budget
« on: June 10, 2019, 08:39:44 AM »
I'll note that the SR1.5 came out within weeks of the previous "carbon budget" for 1.5C was depleted, and gave it 8 more years.  I'm skeptical that this update was driven by science more than by politics.  It's just.

whether we want to emit 360 more gigatonnes or 1100 more gigatonnes, the math is simple.  360 gigatonnes / 7.7 billion = 46.75 tonnes remain for each person on earth.  At the global average of 5.25 tonnes per annum, that's a shade under 9 years before the world population would need be carbon neutral.

don't forget Whales & Dolphins that might show up & drive up shoaling of deep ocean water.  I wanted to include Biology and Chemistry in the topic.  I'd rewrite for a new topic if anyone has a better heading.  I'm reminded of a book - put yourself to the test

Dr Judah Cohen has updated the AER blog June 7:

Continued northern blocking predicted by GFS ensemble rolling forward

*edit how do I make a chart like this?


Actually a calmer looking projection in that run.  Models flip flop between continued high polar cap height anomaly and some calming, well under 240 hrs before the next block either bobs into the Arctic, or the polar front stays intact and the pattern shifts

I think I'm gonna go get some corn

Consequences / Re: Climate change, the ocean, agriculture, and FOOD
« on: June 04, 2019, 08:37:19 AM »
Picture taken May 31 over Eastern IL near the border of IL & IN

The top slowest years for #corn planting on June 2:
1) 2019 67%
2) 1995 77%
3) 1982 85%
4) 1983 86%
5) 1996 86%
6) 1990 87%

I'm scared.  We're seeing an inability to adapt to minor stuff.  This thing has been coming on & growing for over 18 months.  We saw it in November 2016, and in November 2018 it accelerated even more.  Nobody's talking about it, why?  Are we afraid of being laughed at or ran out of town? 

You're not stupid.  You're just supporting the orderly process of discussion and discovery that worked great when we weren't in a catstrophe.

It's not scientists responsibility to fight for our lives, it's people like me who can see it... who don't have a responsibility to science, but have a responsibility to our family & communities... it's we who need to stand up and start understanding and talking about this.

These forecasts are more than ten days out - might mention that in the text.

i am not a scientist <-- it says it right here.  of course they are.  the topic of the thread ends with "long range weather forecasting".  You know, just like summer outlooks, CFS, CanSIPS, RCPs, and millions of conversations about next year, none of which are splashed with warnings about uncertainty in the 10 day forecast

I'm not responsible if you show up with an umbrella when it's sunny out.  But that granular focus to which 5, 8, 10 day uncertainty applies is not relevant to the topic.  I'd rather see a model fail and stipple out on something it can't grapple with so I can think about that and observe how whatever patterns it was projecting actually play out in real life

this isn't an observational science to me.  this is runaway climate change.  whatever climate & weather communications thus far have resulted in the US being record breaking short corn going into a planting season with no prospect of better conditions coming

In 1930 and early 1931, the Oklahoma and Texas panhandles were known as the most prosperous regions in the nation. For plains farmers, the decade opened with prosperity and growth. But in the summer of 1931, those farmers would face the most difficult eight years of their lives.... The rain simply stopped.

Maybe you don't realize it yet.  I'm safe saying the US corn yield will be down 20-30% in 2019

and that's just the tip of the iceberg

All I'm doing is seeing the truth and telling it like it is.  I'm clearly not playing scientist.  I'm trying to figure things out, do I buy my family food or air filters?  do I move?  Because I want to do that before the rush.

While we still have time I'm going to use my intelligence to figure out exactly how this thing is swinging, with or without this forum.  Please help examine the models & present conditions & reanalysis so the developing catastrophic situation can be understood

that's the last I'll say about it.

I think you are correct but I don't think it's exactly accurate to say the polar cell is failing -- the *single* polar cell system is now changing into a state where we have two smaller continental polar cells centered over North America and Eurasia, with increasing dominance of the NAmerican cell (IMO).

So, yes, the single-polar-cell system is failing, but we still have polar cells, they are just centered in abnormal locations and are now advecting heat into the High Arctic instead of dissipating heat entering the High Arctic (at least, advection is now occurring more often than dissipation).

I think I understand what you're saying..  is it like the pattern of "polar cell" has become more chaotic? 

What traces would this leave on a chart?  I'm seeing a lot of 500mb & even some 250mb easterly winds.  When the jet stream breaks in the Arctic and leaves an in intense anti-cyclone, it often moves in retrograde.  I bet that would look good on a map... but which one?

For the past 1-2 days, none of the models can decide where the next block comes from.  I hope this means the polar front stays intact

however a few runs have given a very high (360 meter plus) 500mb anomaly within 240 hours, something i've not seen since February-March

must be lining up with some wave action?  none can decide where it shows up

these blocks ripping through the jet stream into the arctic / ridges pinching off highs in the arctic / jet stream amplitude causing accelerated arctic warming... whatever has been happening more and more over the past 18 months

STILL is showing no sign of changing pattern.  Already looks like a lot of summer outlooks are going to be invalidated.  it just keeps getting worse and worse and worse

Science / Re: Projecting to 2150
« on: June 04, 2019, 06:04:40 AM »
We should be letting people know how bad it's going to get by 2030.

Yes.  It's time not just for scientists but for the citizens to stand up.  It's cold comfort but we might as well go down fighting for what's right.  it's easier.

look how vulnerable we are to almost nothing.  the structure of climate is merely degrading and we have this much trouble.  we have a profound problem.  i don't get the sense people realize it.

James G Anderson

watch this interview.

In the model runs (look at fv3 hour 200-262 from today 06z!)  The high pressure incursions are traveling CCW about Hudson Bay, incursions from the Atlantic are blowing right through the polar cell and exciting on the other side of the planet

Similar story on the Scandinavian block

The ridiculously resilient ridge and Scandinavian block are meeting at the North Pole

So far it has been exaggerated by the models and reality has seen the polar front remaining intact even when the ridge pushed above 80N and fed out anticyclones over the North Pole.  Instead of such sharp features derived by the model you see reality much more diffuse and maybe not as severe--but still

We do not have words for what is happening, so I will defer to one of the greats

Hahaha.  Ok

Long story short?  The cold is pulled away from the Arctic ocean and over the land.  Mirrored by atmospheric circulation.  This much is obvious.  Why that's the case .. ??  The literature points to the thinning sea ice.

Nobody expected the blocks from E-W to show up like they have and cause this much trouble, this early.  In fact, nobody has come out and said much about what's happening now.  But I am not a scientist.  I'll say it:  Earth's northern polar cell is failing.  This looks like the abrupt scenario.

You be the judge.


Recent Arctic amplification and extreme mid-latitude weather

Impact of sea ice cover changes on the Northern Hemisphere atmospheric winter circulation

Stratospheric response to Arctic sea ice retreat and associated planetary wave propagation changes

Amplified Arctic warming and mid‐latitude weather: new perspectives on emerging connections

Evidence linking Arctic amplification to extreme weather in mid‐latitudes

Weakening of the stratospheric polar vortex by Arctic sea-ice loss

Go to Google Scholar and key in Jennifer Francis, Judah Cohen, Jason Furtado, Baek-Min Kim, Kai Kornhuber, Dim Coumou, Stefan Rahmstorf, Potsdam Institute, etc etc.

Best briefing available is to read the papers if there isn't an academic lecture available on YouTube

for example:

Stratosphere-troposphere coupling across timescales - Jason Furtado

Jennifer Francis discussing jet stream in 2017

timestamp 2255 (37:35)

Fast atmospheric response to a sudden thinning of Arctic sea ice

Semmler, T., Jung, T. & Serrar, S. Clim Dyn (2016) 46: 1015.

In order to understand the influence of a thinner Arctic sea ice on the wintertime atmosphere, idealized ensemble experiments with increased sea ice surface temperature have been carried out with the Integrated Forecast System of the European Centre for Medium-Range Weather Forecasts.

The focus is on the fast atmospheric response to a sudden “thinning” of Arctic sea ice to disentangle the role of various different processes. We found that boundary layer turbulence is the most important process that distributes anomalous heat vertically. Anomalous longwave radiation plays an important role within the first few days before temperatures in the lower troposphere had time to adjust. The dynamic response tends to balance that due to boundary layer turbulence while cloud processes and convection play only a minor role. Overall the response of the atmospheric large-scale circulation is relatively small with up to 2 hPa in the mean sea level pressure during the first 15 days; the quasi-equilibrium response reached in the second and third month of the integration is about twice as large. During the first few days the response tends to be baroclinic in the whole Arctic. Already after a few days an anti-cyclonic equivalent-barotropic response develops over north-western Siberia and north-eastern Europe. The structure resembles very much that of the atmospheric equilibrium response indicating that fast tropospheric processes such as fewer quasi-barotropic cyclones entering this continental area are key opposed to slower processes such as those involving, for example, stratosphere-troposphere interaction.

yup.  kinda stalled out there (animates on click)

Incredible FV3-test model run from last night.  These things turn down different paths around hour 150 and derive some pretty wild results.  today's 12Z fv3 is sickening

click to run if you wish

Hour 108 T2anom from the interim GFS-FV3.  I find it interesting that the heat is stacking up right over the two cold poles that have been driving the polar atmosphere to circulate in two parcels.  what this means?

this model produced a wave 8/4 pattern in the final hour of yesterdays 18Z.  forecasters are offering views of wave 6, i dunno.

in my view, this June is going to be extremely chaotic & patterns hard to describe, but 8/4/2 makes sense given the splitness of the polar cell

Arctic sea ice / Re: The 2019 melting season
« on: June 01, 2019, 05:18:49 PM »
North coastline of Alaska is nearly open.  open water all the way to Axel Heiberg or even deeper in about a day

Consequences / Re: Climate change, the ocean, agriculture, and FOOD
« on: May 29, 2019, 04:42:29 AM »
The US just blew threw the record for prevented planting of corn. 

On May 26, the United States still had 99 million acres of both #corn and #soybeans left to plant. That is the most ever by far.

The forum / Re: New participant perspective
« on: May 28, 2019, 01:50:59 AM »
None of this matters to the physics.  This isn't an advocacy group

Air temperatures in the Arctic.  This is DJF 1000mb potential temperature.  You'll get the same signal from 1000-850mb for air temperatures.

In the cylindrical view it has the character of a standing wave.  No wonder chaos reigns.

The rest / Re: Climate on Reddit
« on: May 27, 2019, 03:11:28 AM »
true about the twitter feeds.  I just meant watch out for bots, too.

no room for an honest word any more.

the target seems to be those who engage with it.  the idea is to demoralize them so they stop speaking out.  because we're in a shit fire in 2019, they will keep coming now.  bots too.  people will do anything for no good reason, interfere with the obs next.  prank emit refrigerants.  the mood seems to be that whatever happens will be good.  death, whatever.  good.  because "just say anything" is a cheap attack on information.  and to a species that has evolved to focus on social bullshit, holding sway over conversation is far more valuable than fending for yourself.  it's a life that's only possible in complexity, and it's the first niche that will go away when things simplify further.  i just don't want to acquire bias by caring.  because i'm scared, and i don't want to lose my wits.

weather plays a big role in human mood.  changing weather, heat, severe weather & disasters all play out as different attitudes down the road.  the mood is changing and a lot of people are vocalizing it.

we are so spoiled rich, with the Earth as it was for the past 10,000 years.  it allowed civilization to become unfit in character.  there's no respect for life.  until now, superabundance made anything acceptable.  all you had to do was be in a group, hoot nonsense, and you were taken care of.

the groupies are hooting loudly into the darkness these nights

The rest / Re: Climate on Reddit
« on: May 27, 2019, 01:43:46 AM »
It's 2019.  be aware of bot floods especially when something is happening.  people are probably working to take down obs right now.

fixed the heavy loading of gifs, thank you for the help

Great contributions Sark .. but could you please up size to 701pixel so that they don't all load together .. and eat up resources unnecessarily  ? Also allowes the viewer a little more control ..  cheers b.c.

I haven't figured out how to correct the scaling & sizing issues of this forum yet, can you be more specific or point me to the right place to read about some better practice?

Arctic sea ice / Re: The 2019 melting season
« on: May 26, 2019, 01:02:16 PM »
[Isn’t there a meta-topic somewhere?]

To get back to topic, right now the big question is how long will HP stay on top of the CAB. We are still one month from the solstice but insolation curve is extremely steep near the pole. There will be a lot more solar energy every day.

I don't see a change in pattern until June 15 with a couple fragments of low returning to the Arctic via Greenland.  The Kara is going to get blowtorched June 2-9.  At the same time, ridging from the Pacific will reach into the Beaufort but a little closer to CAA and not as emphatic.  I think this next incursion will NOT be as strong or deliver such a pinched off anticyclone of the jet stream, like the current incursion has.

I still think we will enter summer in wave 5. 

I made my guesses at beyond June 10th below

1st image is ESRL 1000mb air temperature anomalies month by month, 2012-2018 compared to 1979-2000.  This shows that the temperatures have dropped significantly around Hudson Bay, especially in March April May.  The big signal here is that in recent years, the Polar Cell has elongated toward Hudson Bay and Siberia.  Meanwhile, ridging from both oceans has taken turns reaching into the Arctic and delivering those bursts of high temperature we all get excited about, the DMI 80N movers.  However, those Arctic incursions have always came singly, and not from both sides of the planet at the same time.

Dr Judah Cohen has published AER's summer temperature forecast.

2nd image attached is AER's GEFS Polar Cap Height including forecast.  The current conditions are updated here:

3rd image is now a 7 day composite of the 500 mb anomaly from ESRL, and the 18Z GEFS 5 day averages tacked onto the end, which is what I stare at to guess where in the Arctic will get hit by these recurring short circuit ridges.  Looks like once this Bering Blast wears out, another long reaching ridge coming across the Kara Sea brings another big block of high pressure right to the pole.

Gav's weather vids on YouTube has been doing analogs and seasonal models of interest in the UK.  The analogs have been extremely interesting.

Michael Ventrice on Twitter: "With a strong suppressed phase of a Kelvin wave to pass the Western Hemisphere during early June, I'm thinking severe thunderstorm activity in the U.S. quiets down. Good news for parts of the Plains.  Early June likely meaning June 7-20+"

Michael Ventrice regularly reports on the synoptics and there's a great image here.  Little bit over my head with the MJO.  He's been "bearish" on El Nino lately.

I've been staring at models until I can see it with my eyes shut.  I've been doing this because it seems like something is very wrong.

Firstly, GFS runs hot & is a little bit fast at the end.  When I see a high 500mb anomaly, the resulting action is much more diffuse and less sharp.  The GFS paints a bright dot on an area, reality waters it down.  Same amount of ink, just spread out.

The timing of GFS is a little bit fast in the 10-16 day.  Whatever it was developing speeds up at the smaller resolution and the temperature and speed runs away.  What is depicted turns out to be less energetic.

I like how it is "sensitive" and one run van vary widely from the next, but you get great indications of major moves 16-20 days out in the hour 384.

Yeah and it will suffer a heat wave right over the Beauforts area, above zero temps with high pressure in 15-20 days.  I guarantee it.

Ask me how I know

Someone asked me how I knew the Beaufort would be buried in high pressure & heat May 21-26.  I wanted to say something pithy about the value of long range GFS.  I mean, it's working.  But there's more to it. 

Hurricane Oscar, the last named hurricane of the 2018 Atlantic Season was turned out to sea and became and extratropical cyclone.  It entered the Arctic on November 1.  500mb charts from GFS and ECMWF showed it entraining with the polar cell and landing right at the north pole around November 5th.  Within days, the stratospheric polar vortex began ping ponging around the Arctic.  Displacement eventually yielded elongation, splitting, and a notable 3 PV setup.  The PV split worked its way down to the ground for 5 weeks, and then we had the major arctic air outbreaks of last winter.

Since all this happened, the flow has been often split and two major sections of polar cell depart the Arctic for colder land.  The two cells find separation while the jet stream reaches up from both oceans and short circuits at the pole.

4th image.  Big time separation.  There are now two areas of polar cell instead of one.  It is a repeating pattern of meandering, pinching in half, churning in heat at the pole, and then slapping back together again.  It repeats and repeats coming every 6 or 8 weeks.

Now you can expect there will be ridging from opposite sides of the planet at the same time, nearly reaching the pole simultaneously.  The aggressiveness of GFS often shows waves crossing the Arctic and landing on the other side of the planet.  In reality, it's a little bit less simultaneous, a little bit less of a short circuit.

So, what we can all see in the models is a new block of high pressure forming in Russia and then curling into the Arctic, buring the Kara Sea in high pressure and warmth incursion, and delivering another parcel of high pressure to the Arctic.  This is shown in the June 1-9 period.  It is accompanied by a ridge from the Pacific reaching toward the Beaufort.  Models are showing this one a little less energetic and low pressure begins to deepen in the region of Greenland & Baffin Bay around June 10.

Developers Corner / Re: Test space
« on: May 26, 2019, 10:07:38 AM »
 1000mb temperature anomaly by month, 2012-2018 vs 1979-2000

tiled in gimp with python

Arctic sea ice / Re: The 2019 melting season
« on: May 24, 2019, 09:33:51 AM »
When has the 500mb anomaly chart EVER looked so splotchy for so long?  All I see is retrograde motion, pro-rotating cells of cold forced off the ice.  This hasn't yet been spinning up storms in the Arctic.  Should we expect that next?

Arctic sea ice / Re: The 2019 melting season
« on: May 20, 2019, 01:02:00 AM »
This snow is melting comment and objection is an annual tradition.  I just kind hope something structurally changes in week 3 because currently we're in trouble for repeating it next year.

Arctic sea ice / Re: The 2019 melting season
« on: May 19, 2019, 10:43:42 AM »
I decided to do a comparison of SLP for the month of May. I looked at a couple of years and show here 2019 May (so far), 2018, 2016, 2007. Given the forecast, the extreme high pressure seems truly epic

You'd have to allow somehow for the stratosphere/troposphere coupling at final warming.  May won't look normal because the polar cell split in two.  Although it also did it in April, March, February, January, and November, and in 2017, 2016, 2014, etc etc.

It's more split than not at this point.  This should not be happening in the second half of May

Opening this new thread in response to long range weather forecasting discussions in the main melt season thread.  From pages 14-15..  Anything goes.

I would propose a 'Long Term Weather Forcast Thread'.

There are obviously people not interested in this kind of content. By having it in a separate thread they could easily avoid it. And the ones interested wouldn't feel restricted and could post freely.

and I'll open with my "Autosquint" 500mb anomaly 21 day comp mean, with one of today's GFS runs tacked on to the end

This could use a synopsis of the SSW style final warming of 2019, with the ensuing coupled barotropic polar atmosphere that has beaten into the high north.  Analogues, models, papers

I feel like it'll calm down once the snow melts, but 2019 is a continuation of a really disappointing trend.  I spent 3 days curled in a ball last week.  I'm not a scientist and I don't play one so I can say this: The polar cell is failing.  It has been for years.  The trend is not your friend, but it's still a trend... and the emerging trend has to be indicative of the drastic, faster-than-expected breakdown of the polar cell.

What the hell is even happening?

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