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Fall Speculation About Winter 20-21


bluewave
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12 minutes ago, LibertyBell said:

Is it me or did we just begin talking about the Indian Ocean a few years ago?  It seems like before, say, two years ago, the Indian Ocean wasn't even talked about- as if what happened there didn't matter to global patterns?

 

As far as I can tell, there just wasn't that much research on global effects in the past. There was a lot of research on more localized effects. It's gaining more attention more recently though. Probably because it's identified as an area with anomalous warming trends. 

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On 11/12/2020 at 6:14 PM, EasternLI said:

As far as I can tell, there just wasn't that much research on global effects in the past. There was a lot of research on more localized effects. It's gaining more attention more recently though. Probably because it's identified as an area with anomalous warming trends. 

What I want to know is why would the Indian Ocean have more weight on the NAO pattern (why is it warming more quickly?) than either the Pacific or Atlantic would?  What exactly is the Indian Ocean doing and do the Pacific and Atlantic have an influence on the Indian Ocean too?

 

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On 11/13/2020 at 6:13 PM, LibertyBell said:

What I want to know is why would the Indian Ocean have more weight on the NAO pattern (why is it warming more quickly?) than either the Pacific or Atlantic would?  What exactly is the Indian Ocean doing and do the Pacific and Atlantic have an influence on the Indian Ocean too?

 

It's a great question. I'm quite sure the answers are much more complicated than what my current understanding is. I am aware of a few things though. I don't have the data to back this up right now, but there is some relationship with the Indian Ocean and ENSO. Through Ocean current and rossby waves also I believe. Not sure about the Atlantic. I haven't seen anything about a relationship there. Why is it important in regards to the NAO? Mainly, because forcing there strengthens the PV, as it pertains to this year specifically. The following paper describes why that is an issue. 

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019GL084683

The state of the stratospheric polar vortex has a clear impact on the NAE (Scaife et al., 2005) weather regimes (Charlton‐Perez et al., 2018). NAO− is most sensitive to this stratospheric state, occurring on 33% of days following weak vortex conditions but on only 5% of days following strong vortex conditions

The same paper also goes into what to look for if we're hoping for an increased opportunity for some -NAO. As it relates to MJO activity combined with different ENSO states, La Niña for this year. Naturally, other factors are always at work as well to determine what the end result is. In any event, it would seem that we would really like to see the MJO be active through phases 7+8.

We find that the MJO–polar vortex–NAE pathway is strongly active during La Niña years (Figure 3c), particularly for the weakened vortex following MJO phases 8 (corresponding to the third pentad after phases 6–7 in Figure 2), associated with the low in the northwest Pacific following MJO phase 7, increasing vertical heat flux to the stratosphere. There is also a weakened vortex closely following MJO phases 7–8 during neutral years. These contribute to the increased NAO− occurrence around phases 7–8 during neutral and La Niña years (Figure 1).

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Excellent papers guys!  Going to read them now as the big severe weather outbreak is now behind us.  One question I have emanating from this research is will it lead to Nina/Nino like events being defined for the other ocean basins, not just the Pacific?  It could also help with TC forecasting in other parts of the world and the interconnected relationships with global weather patterns!

 

 

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On 11/13/2020 at 11:16 AM, bluewave said:

That’s why getting a favorable Pacific with our -AO and -NAO intervals is so important for snowfall. The Pacific cooperated with the AO and NAO drops during DJF 17-18. But this wasn’t the case in 18-19 with the very hostile Pacific. 

DJF # -AO -NAO days and snowfall........note...the bulk of the 18-19 seasonal snowfall occurred in November and March

17-18......48 -AO days.....8 -NAO days.....NYC snowfall....23.8”......ISP.....29.9”

18-19......42 -AO days....20 -NAO days....NYC snowfall......3.7”......ISP.......4.4”

its not often that everything falls into place like in 1995-96...sometimes you can get lucky in a mild winter...its happened three times in the last 15 years...it can get as cold as one below zero in a warm winter like Feb. 2016...1948-49 had a great second half of December coming off a warm fall...it had a few other snowstorms including a 9.4" the last day of Feb...

winter.........ave temp......snowfall.....big snow...min temp...

2016-17..........39.3..............30.2"..............9.4"..........14

2015-16..........41.0..............32.8"............27.5"...........-1

2005-06..........37.3..............40.0"............26.9"...........14

1990-91..........39.2..............24.9"..............8.9"............10

1982-83..........37.9..............27.2"............17.6"............12

1948-49..........38.5..............46.6"............16.0"............10

1932-33..........37.8..............27.0"............10.0"............11

 

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32 minutes ago, bluewave said:

The February 2016 super El Niño was one of the few months that the SE Ridge or WAR wasn’t a factor. I posted this in the other the other thread.

The SE Ridge has only relaxed for 3 out of the last 15 DJF met winter months. The 3 winter  months it hasn’t been a factor since the 15-16 winter were Dec 17, Feb 16, and Jan 16. We should probably develop a SE Ridge or WAR index like the other teleconnections since it has become such a dominant feature of our recent climate.

SE ridge has helped us with snowstorms in the last decade. In the 60's 70's and 80's we had quite a few fish storms.So a SE ridge can be helpful at times

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maybe because the planet is a little warmer the south east ridge is more significant...

snowiest NYC Decembers since 1950 and indices...

year....snowfall big snow..ave temp....oni…...AO.......NAO....PNA....QBO...

2010.....20.1"...…….20.0"...…….32.8......-1.6....-2.631....-1.85....-1.78....10.97

2003.....19.8"...…….14.0"...…….37.6...….0.4.....0.265.....0.64.....0.86...-11.38

1960.....18.6"...…….15.2"...…….30.9...….0.1....-0.343.....0.06.....1.46...-11.36

1959.....15.8"...…….13.7"...…….38.4...….0.0....-0.042.....0.44.....0.66......8.30

2000.....13.4"...…….12.0"...…….31.1...…-0.7....-2.354....-0.58.....1.23...-14.56

2009.....12.4"...…….10.7"...…….35.9...….1.6....-3.413....-1.93.....0.34...-15.57

1995.....11.5"...……...7.9"...…….32.4...…-1.0....-2.127....-1.67.....0.92.....-4.57

1963.....11.3"...……...6.3"...…….31.2...….1.3....-1.178....-1.92....-0.08......5.48

2002.....11.0"...……...6.0"...…….36.0...….1.1....-1.592....-0.94.....1.59.....-0.50

2005...….9.7"...…......5.8"...…….35.3...…-0.8....-2.104....-0.44.....1.38...-25.04

1966...….9.1"...……..7.1"...…….35.7...….-0.3....-1.401.....0.72.....0.09....13.26

1957...….8.7"...……..8.0"...…….40.2...…..1.7.....0.828.....0.12....-0.43...…7.35

2013...….8.6"...……..5.0"...…….38.5...….-0.3.....1.475.....0.95....-0.86....12.52

1961...….7.7"...……..6.2"...…….35.5...….-0.2....-1.668....-1.48....-1.24......6.25

2017...….7.7"...……..4.5"...…….35.0...….-1.0....-0.059.....0.88.....0.89...-18.12

1952...….7.5"...……..4.5"...…….38.4...…..0.1....-1.827....-0.43.....0.93.....-1.65

1990...….7.2"...……..7.2"...…….42.6...…..0.4.....1.277.....0.22....-1.32....10.68

1968...….7.0"...……..5.2"...…….34.3...…..1.0....-0.783....-1.40....-1.44...-11.36

1993...….6.9"...……..4.0"...…….37.3...…..0.1....-0.104.....1.56.....0.72.....-6.00

1969...….6.8"...……..6.8"...…….33.4...…..0.6....-1.856....-0.28.....1.84......5.00

.................................................................................................................

6" plus December snowfalls

date...........amount...AO.........NAO.........PNA.....NDJ ONI...

12/3-4/1957.....8.0"...+0.561....-0.197.....+0.534...+1.6.....ao was rising from negative...

12/21-22/59...13.7"...+1.032...+1.291......-0.812....-0.1.....

12/11-12/60...15.2"....-0.316....-0.916.....+1.527.....0.0

12/23-24/61.....6.2"....-0.862....-2.530......-0.436....-0.2

12/23-24/63.....6.6"...+0.129....-0.103.....+1.218...+1.1.....ao was rising from negative...

12/24-25/66.....7.1"....-2.324...+0.411.....+0.686....-0.3

12/25-27/69.....6.8"....-0.971....-0.148.....+0.547...+0.7

12/27/1990......7.2"...+2.601...+1.950......-0.936...+0.4

12/19-20/95.....7.7"....-4.353....-0.774.....+0.926....-0.9

12/30/2000....12.0"....-4.115....-0.537.....+1.075....-0.8

12/5/2002.......6.0"....-1.938.....-0.479.....+0.672...+1.1

12/5-6/2003...14.0"...+0.481.....-0.197.....+0.784...+0.3

12/19-20/09...10.9"....-4.651.....-1.833.....+0.549...+1.3

12/26-27/10...20.0"....-2.886.....-1.144......-0.284....-1.4

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14 hours ago, snowman19 said:

@bluewave @Allsnow @donsutherland1 Good thread by Griteater, but a VERY bad sign: 

 

Nice post. It could be a part of a Vortex Intensification event (VI) as is described in the following paper. If so, would be terrible news for any -AO prospects. Here's a couple of relevant quotes from the paper. The life cycle of such events, if that's what is indeed occurring, can be up to 80 days. 

Stratosphere‐troposphere evolution during polar vortex intensification

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2005JD006302

Reduced poleward planetary wave heat flux occurs as the circumpolar wind becomes strongest and pressure anomalies penetrate toward the surface. Descending pressure patterns project strongly onto the positive state of the Northern Hemisphere Annular Mode (NAM).

 

Between days −20 to +20, reduced poleward heat flux is observed as the vortex becomes strongest; increased poleward heat flux is observed as the vortex recovers.

 

[41] In our preliminary examination, the anomalous vortex intensification seems to occur preferentially during La Niña conditions.

kYvtMSw.png

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On 11/17/2020 at 7:52 AM, bluewave said:

Rapidly warming SSTs off our coast go together with the record 500mb ridging that we have been experiencing.

 

https://climate.nasa.gov/news/2798/watery-heatwave-cooks-the-gulf-of-maine/

Most of us are familiar with heat waves on land, but in a warming world, heat waves are starting to become common in the ocean, too. One basin in particular, the normally cool Gulf of Maine in the Northwest Atlantic Ocean, has seen several heat waves in recent years and has spent most of 2018 with unusually warm water temperatures.

On August 8, 2018, scientists using satellite data and sea-based sensors measured the second warmest sea surface temperatures ever observed in the Gulf of Maine. Average water temperatures reached 20.52 degrees Celsius (68.93 degrees Fahrenheit) that day, just 0.03°C (0.05°F) below the record set in 2012.

The maps on this page show sea surface temperature anomalies as compiled by NOAA’s Coral Reef Watch, which blends observations from the Suomi NPP, MTSAT, Meteosat, and GOES satellites and from computer models. Shades of red and blue indicate how much water temperatures were above or below the long-term average for the region. The map above shows conditions on August 8, the near-record setting day, while the map below shows conditions across the entire month of August 2018.

The heatwave of 2018 fits with a much longer trend in the region, which is among the fastest-warming parts of the global ocean. In the past three decades, the Gulf of Maine has warmed by 0.06°C (0.11°F) per year, three times faster than the global average. Over the past 15 years, the basin has warmed at seven times the global average. The Gulf has warmed faster than 99 percent of the global ocean.

August 1 - 31, 2018 August 1 - 31, 2018

“We’ve set 10 daily temperature records this summer, after setting 18 this winter,” said Andrew Pershing, chief scientist of the Gulf of Maine Research Institute (GMRI). “We’ve had to add new colors to our temperature illustrations to reflect just how warm the Gulf of Maine has been this year.”

In recent years, oceanographers have come to define marine heatwaves as periods when water temperature rise above the 90th percentile (of average temperatures) for more than five days. In 2018, the Gulf of Maine has spent more than 180 days above the 90th percentile.

The Gulf of Maine stretches from Cape Cod to Nova Scotia, and it is key intersection between cold water masses from the Arctic and warm water masses from the Gulf Stream. The warming trend in this basin likely has two main causes. First is the overall warming of the global ocean as air temperatures and greenhouse gas concentrations rise. Second is the melting of ice in Greenland and the Arctic Ocean, which provides pulses of fresh water that can alter ocean circulation patterns in the region.

“We are seeing a major shift in the circulation in the North Atlantic, likely related to a weakening Atlantic Meridional Overturning Circulation (AMOC),” said Pershing. “One of the side effects of a weaker AMOC is that the Gulf Stream shifts northward and the cold current flowing into the Gulf of Maine gets weaker. This means we get more warmer water pushing into the Gulf.”

“Climate change is likely contributing to the circulation changes through melting in Greenland and the Arctic,” he added, “as well as making long-stretches of warm weather more likely.”

The warming waters are already affecting marine species in the area, according to several news media and scientist accounts. Herring populations (based on fishing catches) seem to be down this year, and researchers and fishermen are seeing more species usually found in warmer waters, such as butterfish and squid. The populations of copepods, a key food source for endangered Northern Right Whales, also seem to be moving with the changing conditions. And puffins have had to adapt in feeding their chicks this year, as the newly common butterfish are too large for hatchlings to swallow.

 

 

 

And yet the seasons and limits for black sea bass get shorter and shorter....when I was a kid it was colder and there were plenty of these around; they would stay inshore til well into November. People were more focused on winter and summer flounder then, so didn't pay much attention to them. The red hake, known locally as ling, was so plentiful we'd shake them off the hook so the captain wouldn't stay on them. I actually do not see much change for either species in that graph. Fishing stocks are so depleted now it is hard to draw firm conclusions, though it makes sense that we should be seeing warm water species more frequently. However, most of them are quite depleted as well. The southern puffer is a fish that has made an appearance in local waters, and unlike the edible blowfish, it's poisonous.

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1 hour ago, weatherpruf said:

And yet the seasons and limits for black sea bass get shorter and shorter....when I was a kid it was colder and there were plenty of these around; they would stay inshore til well into November. People were more focused on winter and summer flounder then, so didn't pay much attention to them. The red hake, known locally as ling, was so plentiful we'd shake them off the hook so the captain wouldn't stay on them. I actually do not see much change for either species in that graph. Fishing stocks are so depleted now it is hard to draw firm conclusions, though it makes sense that we should be seeing warm water species more frequently. However, most of them are quite depleted as well. The southern puffer is a fish that has made an appearance in local waters, and unlike the edible blowfish, it's poisonous.

The fluke size limit is ridiculous in nj. 

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8 hours ago, EasternLI said:

Nice post. It could be a part of a Vortex Intensification event (VI) as is described in the following paper. If so, would be terrible news for any -AO prospects. Here's a couple of relevant quotes from the paper. The life cycle of such events, if that's what is indeed occurring, can be up to 80 days. 

Stratosphere‐troposphere evolution during polar vortex intensification

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2005JD006302

Reduced poleward planetary wave heat flux occurs as the circumpolar wind becomes strongest and pressure anomalies penetrate toward the surface. Descending pressure patterns project strongly onto the positive state of the Northern Hemisphere Annular Mode (NAM).

 

Between days −20 to +20, reduced poleward heat flux is observed as the vortex becomes strongest; increased poleward heat flux is observed as the vortex recovers.

 

[41] In our preliminary examination, the anomalous vortex intensification seems to occur preferentially during La Niña conditions.

kYvtMSw.png

Good stuff. Here is a good tweet by HM from earlier: 

 

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15 hours ago, bluewave said:

This would match the tendency for December to have a primarily +NAO +AO following the Boxing Day Blizzard in 2010 that I posted earlier in the thread. Also notice how such a strong +AO and +NAO that we currently have in November usually carries over into December.

**********

Chris, I take it the inverse does not hold true?  For example, last November featured a respectable -AO.  After that, IIRC, it bounced around in December for a bit and then shot through the roof.

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36 minutes ago, MJO812 said:

People are already getting hyped on social media for the 1st half of December in the east.

 

Eps  looks really good for the 1st week of December  with a big pna spike. 

 

It would be nice to see snow in December 

Well if it's on social media then it must be true!

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1 hour ago, MJO812 said:

People are already getting hyped on social media for the 1st half of December in the east.

 

Eps  looks really good for the 1st week of December  with a big pna spike. 

 

It would be nice to see snow in December 

too bad there's no cold air.  That will just give us 30's and rain....

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1 hour ago, MJO812 said:

People are already getting hyped on social media for the 1st half of December in the east.

 

Eps  looks really good for the 1st week of December  with a big pna spike. 

 

It would be nice to see snow in December 

There is no cold air, look at the EPO, it’s positive as hell, there is a massive AK vortex in place, flooding PAC maritime air into Canada. The +PNA isn’t going to help with that look. Stop listening to JB, the first half of December looks cruddy. Maybe interior northern New England gets something and that’s even a stretch

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1 hour ago, snowman19 said:

There is no cold air, look at the EPO, it’s positive as hell, there is a massive AK vortex in place, flooding PAC maritime air into Canada. The +PNA isn’t going to help with that look. Stop listening to JB, the first half of December looks cruddy. Maybe interior northern New England gets something and that’s even a stretch

First half doesn't look bad at all

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4 minutes ago, SnoSki14 said:

A torched Canada is still cold.

EPS/GEFS look good moving forward however there's not a ton of cold to work with. 

I do like that they're poking further north with the ridging.

I'd want to see the ridge more pronounced, that would promote airflow from the NW vs a W to E flow across Canada which would just be PAC garbage air.

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1 hour ago, Brian5671 said:

Canada is torched with that fast PAC flow-there's no blocking either-yes it's a deep trough but that's not overly cold and it's very early december-climo still against us

I've seen worse for early December, but that looks like an el nino map instead of La Nina..it should be totally reversed..cold Canada,trough in the west,ridge in the east if it was La Nina

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12 minutes ago, KEITH L.I said:

I've seen worse for early December, but that looks like an el nino map instead of La Nina..it should be totally reversed..cold Canada,trough in the west,ridge in the east if it was La Nina

This pattern depicted by the models for early December are more el nino like with a huge pna spike. Euro was trying to thread the needle with a coastal storm.  Eps also has a signal. 

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