Winter 2023-2024

[griteater]

51 minutes ago, Stormchaserchuck1 said:

Try correlating that atmospheric layer to something like the PNA or North American pattern.. you'll find it's pretty useless as an indicator. Nino 3.4 SSTs have a higher correlation to the pattern.  I made a time series a while ago of ENSO variables, and those 3 sigma levels ranked pretty low. Nino 3.4 and 3 SSTs are better. 

In fairness, I don't think any of the variables are a slam dunk with correlations.  But here are 4 El Nino winters with similar values in Nino 3.4 (all Moderate), and they show 4 different patterns for the most part.  It's even more variable with weak El Ninos.  Also, VP usage (with .2101 sigma) would only be accurate within the satellite era back to 1980, so the sample size is limited.

[Stormchaserchuck1]

65-66 and 72-73 -PNA's are the only breaks.. besides that you are like 20/22 in satellite era for stronger events (El Nino = +PNA or GOA low and La Nina = -PNA or GOA high). 

[griteater]

1 hour ago, snowman19 said:

IMO once the +IOD really gets going, the WPAC forcing and SST configuration is going to look way different than it does right now 

I don't have a strong opinion on it.  It just seems like everything is lagging a bit with what the models continue to want to show vs. what ends up in reality (i.e. models showing the MJO more active that what really occurs / SST over the far W Pac remaining warm, etc.), but we'll see

[40/70 Benchmark]

14 hours ago, griteater said:

  

Some thoughts on this...

 

Pinatubo (Jun 1991) injected a heavy dose of aerosols into the stratosphere..."Strong explosive volcanic eruptions, like ones of the Mt. Pinatubo in Philippines in June 1991, inject millions of tons of sulfur dioxide gas at the altitudes of about 15 miles where it interacts with water vapor producing a volcanic aerosol layer that consists of tiny droplets of highly concentrated sulfuric acid."

"...when aerosols get into the stratosphere, very rapid reactions that destroy ozone (especially in high latitudes) take place on the surfaces of aerosol particles. When ozone gets depleted, less UV radiation is absorbed in the stratosphere. This cools the polar stratosphere and increases the stratospheric equator-to-pole temperature difference, creating a positive phase of the Arctic Oscillation."  Source: NASA - Top Story - THE 1991 MT. PINATUBO ERUPTION PROVIDES A NATURAL TEST FOR THE INFLUENCE OF ARCTIC CIRCULATION ON CLIMATE - Mar. 12, 2003

 

Hunga Tonga (Jan 2022) on the other hand ended up injecting a heavy dose of water vapor into the stratosphere..."With this data, Vömel and his colleagues gave a ‘conservative estimate’ that Hunga Tonga injected at least 50 million tonnes of water into the stratosphere. This represents an increase of 5% in the stratosphere’s total water content. The unprecedented water content of the Hunga Tonga plume has a number of implications. The first is that it could explain another observation made by scientists tracking the event: the seemingly low sulfur dioxide content. 'In the eruption column directly over the volcano, the entire stratosphere was probably saturated,’ says Vömel. ‘So you have a lot of ice particles in there and they can certainly wash out a lot of SO2. So there’s another very, very interesting research topic: what happened – was there not a lot of SO2 coming out of the volcano, or was there a lot and it was all washed out?’  Source: One year on from massive eruption in South Pacific, the atmosphere is still feeling the effects | News | Chemistry World

 

Here is a loop I put together showing the increasing water vapor anomalies in the stratosphere from Dec 2021 to Jun 2023 following the Hunga Tonga eruption.  Source: NOAA CSL: Chemistry & Climate Processes: SWOOSH.  1mb to 100mb on the left covers the upper to lower stratosphere, with latitude at the bottom (southern hemisphere to the left / northern hemisphere to the right)

 

Looking at the individual image for June 2023, I've added a black box for the Northern Hemisphere polar cap (60 deg North to the North Pole).  Here we can see enhanced water vapor anomalies extending thru much of the stratosphere, though weaker anomalies in the lower stratosphere.  From what I've read, it's probably going to take a few <or> some years for this anomalous water vapor to subside.  And from Dr. Jennifer Francis (Twitter): "Water vapor is a greenhouse gas, and like CO2, when it’s in the troposphere it warms the surface, but in the stratosphere, it radiates infrared energy to space."...i.e., this would favor cooling in the stratosphere in the coming winter.  Does this mean a cold and strong stratospheric polar vortex and coupled +AO pattern?  Possibly.

 

However, here are a couple of things that may counter-balance...

As mentioned before, -NAO is more common during Strong El Ninos than any other ENSO phase...

 

Also, it's highly likely that we will be entrenched in a -QBO this winter...

Here in this set of images we can see that the negative phase of the QBO is descending (i.e., moving from the upper and mid-stratosphere to the lower stratosphere), and has reached close to 40mb; and should continue its decent down thru the stratosphere over the next few months.

 

 

And during El Ninos, Sudden Stratospheric Warmings (SSW) have occurred in 8/10 cases (80%) when the QBO was negative in winter (40mb on Jan 1).  And in the 8 cases where an SSW occurred during Nino and -QBO, the combined AO/NAO index was negative 6/8 cases (75%).

 

 

In contrast, when the QBO was positive in winter during El Ninos, SSWs have occurred in only 6/13 cases (46%).  And in the 6 cases where an SSW occurred during El Nino and +QBO, the combined AO/NAO index was negative in only 2/6 cases (33%).

Any data on solar activity on the polar domain during el Nino seasons? Intuitively, I feel as though active years, like this one, are more prone to a strong PV.....this was also the case in 1991 in addition to Pinatubo. 

[griteater]

22 minutes ago, 40/70 Benchmark said:

Any data on solar activity on the polar domain during el Nino seasons? Intuitively, I feel as though active years, like this one, are more prone to a strong PV.....this was also the case in 1991 in addition to Pinatubo. 

Yeah factoring in solar with the Strat PV and AO/NAO can get a bit tricky.  The classic combo for a weak PV and -AO/-NAO is when the lower strat QBO is neg and we are in solar min with respect to both solar flux and geomag, which is typically right after the official solar minimum (years like 76-77, 86-87, 09-10).

In lieu of that, I like this simple chart which shows how the strat PV tends to have early warming events during -QBO in both Solar Min and Solar Max conditions, with mid or late winter strat warmings favored during +QBO. 

"....In early winter (November–December), the most disturbed, and most variable, composites are the two QBO/E phase composites. In midwinter however (January–March), the two composites showing most disturbances in midwinter are the Smin /E and Smax /W composites. The disturbed nature of the Smax /W composite thus supports earlier evidence that the Holton Tan relationship is disrupted in Smax years." Source: Solar and QBO Influences on the Timing of Stratospheric Sudden Warmings in: Journal of the Atmospheric Sciences Volume 61 Issue 23 (2004) (ametsoc.org)

 

 

Also, I like the chart in this paper where it shows that the Declining phase of the solar cycle is where the highest NAO values have typically occurred.  This would be the time period of highest solar geomag just after solar sunspot / solar flux max (I suppose we are either in the Ascending or Maximum phases for this winter).  "...Figure 7 verifies the unique nature of the declining phase, the only phase having a mean NAO index (0.46±0.36), which is statistically significantly different from the long-term mean. We note that although the maximum phase has the largest negative mean NAO(−0.20±0.55), which is in agreement with the results depicted in Figure 4, it is not statistically different from the long-term mean. Mean wintertime NAO values during the ascending and minimum phases are close to the long-term mean."  Source: Spatial distribution of Northern Hemisphere winter temperatures during different phases of the solar cycle (wiley.com)

 

[40/70 Benchmark]

On 8/6/2023 at 12:17 AM, griteater said:

Yeah factoring in solar with the Strat PV and AO/NAO can get a bit tricky.  The classic combo for a weak PV and -AO/-NAO is when the lower strat QBO is neg and we are in solar min with respect to both solar flux and geomag, which is typically right after the official solar minimum (years like 76-77, 86-87, 09-10).

In lieu of that, I like this simple chart which shows how the strat PV tends to have early warming events during -QBO in both Solar Min and Solar Max conditions, with mid or late winter strat warmings favored during +QBO. 

"....In early winter (November–December), the most disturbed, and most variable, composites are the two QBO/E phase composites. In midwinter however (January–March), the two composites showing most disturbances in midwinter are the Smin /E and Smax /W composites. The disturbed nature of the Smax /W composite thus supports earlier evidence that the Holton Tan relationship is disrupted in Smax years." Source: Solar and QBO Influences on the Timing of Stratospheric Sudden Warmings in: Journal of the Atmospheric Sciences Volume 61 Issue 23 (2004) (ametsoc.org)

 

 

Also, I like the chart in this paper where it shows that the Declining phase of the solar cycle is where the highest NAO values have typically occurred.  This would be the time period of highest solar geomag just after solar sunspot / solar flux max (I suppose we are either in the Ascending or Maximum phases for this winter).  "...Figure 7 verifies the unique nature of the declining phase, the only phase having a mean NAO index (0.46±0.36), which is statistically significantly different from the long-term mean. We note that although the maximum phase has the largest negative mean NAO(−0.20±0.55), which is in agreement with the results depicted in Figure 4, it is not statistically different from the long-term mean. Mean wintertime NAO values during the ascending and minimum phases are close to the long-term mean."  Source: Spatial distribution of Northern Hemisphere winter temperatures during different phases of the solar cycle (wiley.com)

 

Wow, so solar max is a -NAO signal? I never would have thought...

[40/70 Benchmark]

On 8/5/2023 at 9:26 PM, Stormchaserchuck1 said:

65-66 and 72-73 -PNA's are the only breaks.. besides that you are like 20/22 in satellite era for stronger events (El Nino = +PNA or GOA low and La NIna = -PNA or GOA high). 

Your NAO calculation must be nearly ready...where does it stand?

[Stormchaserchuck1]

22 minutes ago, 40/70 Benchmark said:

Your NAO calculation must be nearly ready...where does it stand?

Region A = +0.30, Region B = +0.13 

A-B/2 = +0.08 DJFM NAO prediction

+0.08 Winter NAO, 65% of the time (May-Sept) through

https://ibb.co/56L3cZX

If it were to end today, 50% chance for -0.46 to +0.62 (0.54SD) DJFM 

[40/70 Benchmark]

3 minutes ago, Stormchaserchuck1 said:

Region A = +0.40, Region B = +0.13 

A-B/2 = +0.13 DJFM NAO prediction

+0.13 Winter NAO, 65% of the time (May-Sept) through

https://ibb.co/k61b23d

So pretty much neutral.

I would take that this season....similar to last year.

[Stormchaserchuck1]

5 minutes ago, 40/70 Benchmark said:

So pretty much neutral.

I would take that this season....similar to last year.

Last Winter the method finished at about +0.30, and the CPC NAO verification was +0.22

[40/70 Benchmark]

2 minutes ago, Stormchaserchuck1 said:

Last Winter the method finished at about +0.30, and the CPC NAO verification was +0.22

Good job last year.

[40/70 Benchmark]

My largest concern about next winter was the volcano, and that is pretty sufficiently assuaged from what I have been reading.

Don't see it as an issue.

[Stormchaserchuck1]

Believe it or not, the ENSO subsurface (I've found to be the strongest indicator overall) is barely positive. 

https://ibb.co/ZWhRppb

[GaWx]

7 minutes ago, Stormchaserchuck1 said:

Believe it or not, the ENSO subsurface (I've found to be the strongest indicator overall) is barely positive. 

https://ibb.co/ZWhRppb

 Indeed, it plunged from mid June through most of July per this though it has steadied out since:

 

[40/70 Benchmark]

11 minutes ago, Stormchaserchuck1 said:

Believe it or not, the ENSO subsurface (I've found to be the strongest indicator overall) is barely positive. 

https://ibb.co/ZWhRppb

Strongest indicator of what, ultimate ENSO peak?

[Stormchaserchuck1]

18 minutes ago, 40/70 Benchmark said:

Strongest indicator of what, ultimate ENSO peak?

PNA pattern, especially in the Winter time. (I guess a lot of lingering negative indicators like the -PDO, are correlating here with the central subsurface region.) 

[40/70 Benchmark]

On 8/5/2023 at 6:52 PM, griteater said:

Here is a comparison for Jun 3 to Aug 3 in 2015 (Basin Wide Super Nino) vs. this year where you can see that the low frequency Walker Cell uplift region (-VP in blue and purple) has been slow to move east so far this year and is still reaching back into the Maritime Continent in spite of the El Nino SSTs being east-based.  So, we'll have to see how that trends going thru the fall

You wonder if the ensuing winter will be impacted by the tenaciously residual cool ENSO atmospheric imprint in much the same manner that the 1995-1996 la nina was by the residual warm ENSO imprint. In 1995-1996, we observed the el nino like active STJ, whereas this season we could see a residual pull west of the seasonal forcing that may look like a compromise between last season and a traditional canonical el nino forcing regime...the end result would be a modoki like forcing signature (near the dateline) overlaid over a robust, basin-wide warm ENSO SST configuration.

Interesting.

Back to regularly scheduled super el nino tweets.

[Stormchaserchuck1]

I wonder, if the subsurface configuration doesn't change, if we see a balance between +PNA's and -PNA's this winter. 

[griteater]

On 8/7/2023 at 10:52 AM, 40/70 Benchmark said:

Wow, so solar max is a -NAO signal? I never would have thought...

Yes, but they mention in the paper that the -NAO signal for solar max is not statistically significant - "We note that although the maximum phase has the largest negative mean NAO(−0.20±0.55), which is in agreement with the results depicted in Figure 4, it is not statistically different from the long-term mean."

The biggest takeaway from that paper IMO is that the declining phase of solar cycles has a robust correlation with +NAO.  The average in 12 of the 13 solar cycles (cycles 11 to 23 from 1867 to 2008) exhibited +NAO or +NAO temperature patterns.  Interestingly enough, the NAO was positive as well in each of the 3 winters in the declining phase of solar cycle 24, those being the winters of 2014-2015, 2015-2016, and 2016-2017.

 

 

Looking back at this year's solar cycle chart, it looks like this year would qualify as one of the solar "Maximum" years.

 

Lastly, I thought this was a good summary in the first section of the paper ("Abstract"): "...Using 13 solar cycles (1869–2009), we study winter surface temperatures and North Atlantic oscillation (NAO) during four different phases of the sunspot cycle: minimum, ascending, maximum, and declining phase. We find significant differences in the temperature patterns between the four cycle phases, which indicates a solar cycle modulation of winter surface temperatures. However, the clearest pattern of the temperature anomalies is not found during sunspot maximum or minimum, but during the declining phase, when the temperature pattern closely resembles the pattern found during positive NAO. Moreover, we find the same pattern during the low sunspot activity cycles of 100 years ago, suggesting that the pattern is largely independent of the overall level of solar activity.

[griteater]

13 hours ago, 40/70 Benchmark said:

My largest concern about next winter was the volcano, and that is pretty sufficiently assuaged from what I have been reading.

Don't see it as an issue.

What have you seen?  What are your thoughts?  I think it is reasonable to have 'concerns' over the volcano having impacts on the behavior of the strat PV given the injection of high water vapor anomalies into the strat.  Increased water vapor would favor a cooler stratosphere (as water vapor in the stratosphere radiates incoming infrared energy)

[GaWx]

 Looking ahead to the possible effects on US winters 2024-5 through 2028-9 from the January of 2022 Tonga volcano, the chance of a multiyear El Niño MAY be enhanced while the volcano still has influence, especially during 2025-9. Note how the DJF temperature anomaly pattern over the US in figure 7a comes rather close to a typical El Niño, including the cool SE and warm NW. Also, note especially figure 11d, which shows an El Ninolike Pacific SSTa pattern. Maybe this will counteract the chance for the Niña that at least one model run (August CANSIPS) was suggesting to be possible for 2024-5??

 

"The MiMA simulations confirm the robustness of the SWV-induced wave structure in the Pacific (Fig. 11ef), and they produce tropical surface temperature anomalies consistent with an El Nino-like pattern (Fig. 11a-d). This heating is produced by the zonally asymmetric distribution of SWV in the tropics, and consistent with the increased surface downward longwave flux over the tropical Pacific in WACCM (Fig. 9a). Thus, it is possible that the SWV forcing from the eruption would favor a positive phase of ENSO on a multi-year timescale, but further work is required to confirm this, in particular with a model including fully interactive ocean and cloud feedbacks."

 

https://www.researchgate.net/publication/372889143_Long-term_surface_impact_of_Hunga_Tonga-Hunga_Ha'apai-like_stratospheric_water_vapor_injection

[40/70 Benchmark]

On 8/9/2023 at 12:09 AM, griteater said:

What have you seen?  What are your thoughts?  I think it is reasonable to have 'concerns' over the volcano having impacts on the behavior of the strat PV given the injection of high water vapor anomalies into the strat.  Increased water vapor would favor a cooler stratosphere (as water vapor in the stratosphere radiates incoming infrared energy)

I'm writing it up right now.

[40/70 Benchmark]

15 hours ago, GaWx said:

 Looking ahead to the possible effects on US winters 2024-5 through 2028-9 from the January of 2022 Tonga volcano, the chance of a multiyear El Niño MAY be enhanced while the volcano still has influence, especially during 2025-9. Note how the DJF temperature anomaly pattern over the US in figure 7a comes rather close to a typical El Niño, including the cool SE and warm NW. Also, note especially figure 11d, which shows an El Ninolike Pacific SSTa pattern. Maybe this will counteract the chance for the Niña that at least one model run (August CANSIPS) was suggesting to be possible for 2024-5??

 

"The MiMA simulations confirm the robustness of the SWV-induced wave structure in the Pacific (Fig. 11ef), and they produce tropical surface temperature anomalies consistent with an El Nino-like pattern (Fig. 11a-d). This heating is produced by the zonally asymmetric distribution of SWV in the tropics, and consistent with the increased surface downward longwave flux over the tropical Pacific in WACCM (Fig. 9a). Thus, it is possible that the SWV forcing from the eruption would favor a positive phase of ENSO on a multi-year timescale, but further work is required to confirm this, in particular with a model including fully interactive ocean and cloud feedbacks."

 

https://www.researchgate.net/publication/372889143_Long-term_surface_impact_of_Hunga_Tonga-Hunga_Ha'apai-like_stratospheric_water_vapor_injection

I think we are going to see a run of +NAO again after the next solar max, unless we see a potent modoki el nino,...Pacific should improve, though....could fathom another stretch like 2013-2015, minus the 100" in 30 days for Boston lol

[40/70 Benchmark]

On 8/9/2023 at 12:02 AM, griteater said:

Yes, but they mention in the paper that the -NAO signal for solar max is not statistically significant - "We note that although the maximum phase has the largest negative mean NAO(−0.20±0.55), which is in agreement with the results depicted in Figure 4, it is not statistically different from the long-term mean."

The biggest takeaway from that paper IMO is that the declining phase of solar cycles has a robust correlation with +NAO.  The average in 12 of the 13 solar cycles (cycles 11 to 23 from 1867 to 2008) exhibited +NAO or +NAO temperature patterns.  Interestingly enough, the NAO was positive as well in each of the 3 winters in the declining phase of solar cycle 24, those being the winters of 2014-2015, 2015-2016, and 2016-2017.

 

 

Looking back at this year's solar cycle chart, it looks like this year would qualify as one of the solar "Maximum" years.

 

Lastly, I thought this was a good summary in the first section of the paper ("Abstract"): "...Using 13 solar cycles (1869–2009), we study winter surface temperatures and North Atlantic oscillation (NAO) during four different phases of the sunspot cycle: minimum, ascending, maximum, and declining phase. We find significant differences in the temperature patterns between the four cycle phases, which indicates a solar cycle modulation of winter surface temperatures. However, the clearest pattern of the temperature anomalies is not found during sunspot maximum or minimum, but during the declining phase, when the temperature pattern closely resembles the pattern found during positive NAO. Moreover, we find the same pattern during the low sunspot activity cycles of 100 years ago, suggesting that the pattern is largely independent of the overall level of solar activity.

Yea, my main takeaway is that it doesn't favor a strong PV...not that its a slam dunk for weak.

[40/70 Benchmark]

On 8/5/2023 at 8:29 AM, griteater said:

However, here are a couple of things that may counter-balance...

As mentioned before, -NAO is more common during Strong El Ninos than any other ENSO phase...

 

Also, it's highly likely that we will be entrenched in a -QBO this winter...

I would bet anything its because most of those strong el nino, neg NAO events were modoki, or at least westward leaning....and probably mostly solar ascending, too.

[raindancewx]

The major cool-off / wetter period we're seeing now in New Mexico, back to seasonal conditions, is consistent with the subsurface flat-lining.

Once we get a burst in subsurface temps, it should get very cold pretty quickly. But I don't really expect the flat subsurface period to end for a bit.

I know everyone likes to talk about how warm the Indian Ocean warm pool is v. the ENSO regions...but surely the incredible heat in the Gulf of Mexico matters too? There have been 100F observed waters near Florida this Summer. Indian Ocean is nowhere near that warm. Small places off Western Mexico are also super warm.

[40/70 Benchmark]

18 minutes ago, raindancewx said:

The major cool-off / wetter period we're seeing now in New Mexico, back to seasonal conditions, is consistent with the subsurface flat-lining.

Once we get a burst in subsurface temps, it should get very cold pretty quickly. But I don't really expect the flat subsurface period to end for a bit.

I know everyone likes to talk about how warm the Indian Ocean warm pool is v. the ENSO regions...but surely the incredible heat in the Gulf of Mexico matters too? There have been 100F observed waters near Florida this Summer. Indian Ocean is nowhere near that warm. Small places off Western Mexico are also super warm.

I don't think it's just magnitude of the anomaly, but also the aerial coverage...they both play a role....kind of like ACE with respect to hurricanes. 

[GaWx]

1 hour ago, raindancewx said:

The major cool-off / wetter period we're seeing now in New Mexico, back to seasonal conditions, is consistent with the subsurface flat-lining.

Once we get a burst in subsurface temps, it should get very cold pretty quickly. But I don't really expect the flat subsurface period to end for a bit.

I know everyone likes to talk about how warm the Indian Ocean warm pool is v. the ENSO regions...but surely the incredible heat in the Gulf of Mexico matters too? There have been 100F observed waters near Florida this Summer. Indian Ocean is nowhere near that warm. Small places of Western Mexico are also super warm.

 The 100 & 101F SST measured at the buoy in Manatee Bay, FL, made the headlines in the typical sensationalized manner. They appear to have been true readings, but they weren't at all comparable to ocean buoy SSTs. Rather, they were measured in a very shallow and sheltered bay barely off land with the sunlight absorbing dark muddy bottom quite visible. They were measured in the equivalent of a large/deep mud puddle. There are likely numerous very small bodies of water that get that hot or hotter every year that aren't measured. It had 10F 24 hour ranges and it plunged to 84 2 1/2 days later. Even Dr Masters said this isn't a legitimate SST. Other buoys nearby were in the upper 90s, which also weren't legit.

 But what was/is legit is the Key West buoy's 92+F's hottest, which is itself breaking records.

 

[griteater]

Euro Aug 1 Seasonal has a slightly weaker than normal Strat PV at 10mb beginning in mid-Dec and extending to early Feb on the ensemble mean.  Let's see how this trends going forward, but just going off memory, the Euro tends to do a decent job with Strat forecasting

 

[40/70 Benchmark]

3 hours ago, griteater said:

Euro Aug 1 Seasonal has a slightly weaker than normal Strat PV at 10mb beginning in mid-Dec and extending to early Feb on the ensemble mean.  Let's see how this trends going forward, but just going off memory, the Euro tends to do a decent job with Strat forecasting

 

This is in line with my preliminary ideas.