El Nino 2023-2024

[so_whats_happening]

5 hours ago, griteater said:

Update to TAO loop (in 10-day increments).  Some downwelling warmth moving in on the latest image

Yea i have this feeling we may have peaked in 1+2, until the nino dies which we may revisit those upper numbers again toward end of winter. It looks as though a solid bout of trades picks up again to close out the month as the weak mjo wave moves. Given this i dont expect another warming progression until mid to late september at the earliest. Let us see how everything holds up.

We still dont have the -surface/subsurface across much of the WPAC yet. So in true nino fashion i expect at least one more big KW before we may peak out in October, maybe November depending on timing. I dont expect a quick demise after this but that will have to be worked out closer to when this progression happens.

[bluewave]

59 minutes ago, so_whats_happening said:

Yea i have this feeling we may have peaked in 1+2, until the nino dies which we may revisit those upper numbers again toward end of winter. It looks as though a solid bout of trades picks up again to close out the month as the weak mjo wave moves. Given this i dont expect another warming progression until mid to late september at the earliest. Let us see how everything holds up.

We still dont have the -surface/subsurface across much of the WPAC yet. So in true nino fashion i expect at least one more big KW before we may peak out in October, maybe November depending on timing. I dont expect a quick demise after this but that will have to be worked out closer to when this progression happens.

While several ENSO models are going super, the subsurface is still much less impressive than at this point in 2015 and 1997.  I know it’s only a small sample size of two. But the current upper ocean heat content near +1 is much lower than the +2 values those years at this time. So not sure how we get to super status without the upper ocean heat doubling from +1 to +2. Not really seeing that yet with the trades returning and the WPAC forcing to start September. Right now looks like 1+2 may have peaked and 3, 3.4, and 4 will continue a slow but steady climb as the SST departures work west. This year could be a candidate for an early peaking event should the follow up kelvin wave activity remain as weak as it has been. Also note the lack of a WPAC cold pool which helped development in 1997 and 2016 with the very impressive WWB activity near the Dateline which has been missing this year.

 

[40/70 Benchmark]

7 hours ago, Typhoon Tip said:

Fwiw, the solar activity does not, however... just sayn'

Depends which research you read.

[roardog]

I like how there’s so many mixed signals and differing opinions this year. In 2015 at this time you knew a super Nino was coming. As an enthusiast of this stuff, I find this year more interesting. 

[40/70 Benchmark]

3 hours ago, GaWx said:

 I appreciate your work and optimism about a -NAO this winter since I'm also a winter lover and thus hope you're right. Over the last 44 winters, -NAOs (I define as sub -0.25) for DJF have been few and far between:

1984-5: (NAO -0.70) (moderate La Niña) headed down in cycle 21 with limited sunspots averaging only 20/month; this was 20 months before the minimum of Sept 1986

1986-7: (NAO -0.30) (moderate El Niño) very early in cycle 22 four months after the Sept 86 minimum with very limited sunspots of only 6/month 

1995-6: (NAO -0.62) (moderate La Niña) headed down in cycle 22 with limited sunspots of only 12/month nine months before Sept 1996 minimum

2009-10: (NAO -1.67) (strong El Niño) one year into cycle 24 at 13 months after the Dec 2008 minimum just starting to head upward but with still limited sunspots of only 22/month

2010-11: (NAO -0.68) (strong La Niña) two years into cycle 24 at 25 months after the Dec 2008 minimum headed further up but still low at 33/month

2020-1: (NAO -0.42) (moderate La Niña) early into cycle 25 at 13 months after the Dec of 2019 minimum just starting to head up but still with limited sunspots of only 14/month

---------------------

 Note that there has been either one or two -NAO winters during each of the last four quiet portions of the cycles!

 So, based on the last 44 years of -NAO winters, the data clearly shows that being within two years of a minimum (ascending or descending) along with limited sunspots (so, nowhere near a cycle max) has given the best chance for a -NAO winter. The average distance from minimum was only 14 months.

 So, for these last six -NAO winters, the average monthly sunspots were all low to very low: 20, 6, 12, 22, 33, and 14 for an average of only 18. This 18 compares to the longtime average monthly sunspots of 85 (based on 1900-2022 data).

  ---------

 Where are we going to be in the current solar cycle this winter? 49 months past the prior minimum (Dec of 2019), which is much closer to the upcoming maximum than the prior minimum. We're at 134/month so far in 2023 with it rising. So, per extrapolation, there's a very good chance that this winter will be 150+ or not far from twice the longterm average of 85. So, very high sunspot activity nearing a maximum is quite likely.

 So, if this winter were to have a -NAO, it would be practically totally opposite of the others over the last 44 years regarding the solar cycle. This along with there being a -NAO (sub -0.25) during only 1/7 of the last 44 winters and only one of the last 12 winters tells me that anyone who doesn't predict a winter -NAO often but is doing so this winter would deserve major kudos if a -NAO were to verify since the odds seem to me to be so stacked against it. Thus, it will quite interesting to see what happens this winter, -NAO or not. As a winter lover, I'd love to see the recently rare -NAO. I'll probably later also post this in the winter prediction thread.

Monthly NAO since 1950:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table

 

Monthly sunspots:

https://www.sidc.be/SILSO/DATA/SN_m_tot_V2.0.txt
 

 

Looks to me that ascending vs descending is more important than minimum vs maximum.

Influences of the Solar Cycle on the Polar Fields

The impact of the solar cycle and the stratosphere on the earth's atmosphere continues to be a work in progress and much like seasonal forecasting in general, it is still very much a frontier science. Traditionally, research correlated high levels of solar activity near solar max to a stronger polar vortex and thus milder winters for much of North America and Europe. There are a multitude of theories as to why this is the case, however, most of these theories cite drivers such as UV radiation and total solar radiation (TSI), which closely mirror sunspot activity, as responsible for increasing ozone levels and temperature in the equatorial stratosphere. This warmer tropical stratosphere then results in a stronger latitudinal gradient and a cooler polar stratosphere (stronger polar vortex) via a modulated Brewer-Dobson cycle. The issue with these theories is that the peak levels of the aforementioned potential drivers of the solar-stratosphere connection coincide with solar max. And most recent research cite stronger drivers that do not coincide with solar max, such as geomagnetic energy and solar winds, which peak during solar flux or, about one year after solar max in terms of peak UV and TSI . (Maliniemi et al, 2014). Malimiemi et al theorize that geomagnetic energy makes its way into the polar region via the process of energetic particle precipitation, which then produces nitrogen oxides in the the upper atmosphere that have a protracted period of time to descend downward and increase ozone during the polar winter in the absence of any sunlight, which cools the stratosphere and strengthens the PV. This more closely corroborates both with other recent research, which cites drivers that do not peak at solar max as defined by UV and TSI (geomagnetic energy peaks approximately one year after solar max), as well as the research of Malimiemi et al (2014), which found that the declining phase of the sunspot cycle remarkably consistently produces the spacial pattern of surface temperature anomalies related to the positive NAO during the last 13 solar cycles" (Maliniemi et al, 2014). This makes sense since the geomagnetic energy peak that Maliniemi et al cite as the main driver behind the connection between the solar cycle and polar domain lags solar max as defined by UV, TSI and sunspots by approximately one year, which is during the declining phase that so strongly correlates with the +NAO response in their research. This is also consistent with other recent studies of seal level pressure patterns that revealed a +NAO pattern lagging solar max by approximately 2-4 years. The work of Maliniemi et al also showed that this relationship is not at all dependent on overall sunspot activity due to intra-cycle variability. 

 

Mean winter NAO index values for the four cycle phases, averaged over cycles 11 to 23. The red line represents the overall mean value of wintertime NAO (0.05). Bars represent the 95% confidence intervals.

 

Perhaps more germane within the context of the coming winter is that the study found that both the solar max and the ascending portion of the solar cycle are weakly correlated to a colder pattern redolent of the -NAO, although this is more dependent on intra-cycle variability of activity. There is no clear correlation between the solar minimum and the NAO, but perhaps modest one that perhaps a modest negative correlation.

 

 

These relationships between solar behavior and the NAO are evident in the graph above, with reds, denoting +NAO, very evident in the declining phase of the last several solar cycles. And Blue, indicative of -NAO, prevalent in the ascending portion of the cycles. Winter 2023-2024 will be in the ascending phase with the peak of solar cycle 25 anticipated within the next couple of years, thus an exceedingly strong PV is unlikely in the mean during the coming boreal winter season.

 

 

Now we can view the aforementioned EMI analogs through this solar lens in an effort to gain clarity into why the polar domain behaved in the manner that is did in each respective case.

 

In the case of the 1986-1987 winter season, given that solar minimum occurred during prior fall in September of 1986, that particular season occurred near the solar minimum at the onset of the ascending phase. This is consistent with the research marginally favoring a negative NAO.

The 1994-1995 cold season coincided with the descending phase of solar cycle 22 given that the minimum was observed in August of 1996, which also corroborates the research of Meliniemi et al that favors a +NAO during this portion of the solar cycle. Finally, the 2006-2007 winter season also took place during the descending phase of solar cycle 23, as the minimum was in December 2008. This season featured both a +NAO and exorbitantly potent PV in the seasonal mean.

 

 

[40/70 Benchmark]

9 minutes ago, roardog said:

I like how there’s so many mixed signals and differing opinions this year. In 2015 at this time you knew a super Nino was coming. As an enthusiast of this stuff, I find this year more interesting. 

I went into this season believing that a +NAO was favored due to nearing solar max, but that doesn't look to be the case. I guess we'll find out in a few months.

[40/70 Benchmark]

1994 and 2006 are two perfect examples...right mear solar min, yet two very strong PV seasons....why? Descending sun.

[40/70 Benchmark]

2009-2010 also near solar min, but on the other side...ascending....the rest is history. Solar isn't the only factor and there are some exceptions, but this ascending vs descending dichotomy checks out most of the time looking back. 

1957-1958 was ascending near solar max with a strong el nino, like This year....big blocking. 

I'm not trying to say slam-dunk -AO/NAO....I just think it's a bit more up for debate than some of us think. 

[40/70 Benchmark]

3 hours ago, snowman19 said:

@Volcanic Winter Could you offer some insight into this please?

Like the solar relationship, the impact of volcanic eruptions on the polar domain is also over simplified and poorly understood. There are a multitude of factors such as location of the eruption and global wind circulation patterns that dictate how it impacts the poles, if at all. Some have no impact...some produce negative AO/NAO.

[40/70 Benchmark]

If this el nino ends up with an ONI near 2.0 and the forcing makes it as far back east as about 160W, then none of this is likely to matter because we are cooked. Canonical el nino forcing that powerful would be the main driver.

[raindancewx]

You have to be careful with the solar stuff. The cycles are not always 11 years. Historical range from min to min or max to max is 9-13 years. So a year that looks like it is still climbing or falling can be the top/bottom of the cycle. The prior min was centered on February 2019, so we may already be at the peak (Feb 2024 would be +5 years from the min).

We've been seeing the tendency reversal in temperatures I speculated on earlier. The SW US heat wave in July coincided with a record drop in subsurface heat for a warm ENSO event. Now the subsurface is warming, and it is cooling off quickly locally. We've had several cool days this month after none at all for six weeks.

[GaWx]

9 hours ago, Typhoon Tip said:

Fwiw, the solar activity does not, however... just sayn'

Please explain

[40/70 Benchmark]

Yea, I know it varies, but I'm def no expert on the solar stuff...just used the min/max dates listed on the wiki page.

[GaWx]

4 hours ago, 40/70 Benchmark said:

Looks to me that ascending vs descending is more important than minimum vs maximum.

Influences of the Solar Cycle on the Polar Fields

The impact of the solar cycle and the stratosphere on the earth's atmosphere continues to be a work in progress and much like seasonal forecasting in general, it is still very much a frontier science. Traditionally, research correlated high levels of solar activity near solar max to a stronger polar vortex and thus milder winters for much of North America and Europe. There are a multitude of theories as to why this is the case, however, most of these theories cite drivers such as UV radiation and total solar radiation (TSI), which closely mirror sunspot activity, as responsible for increasing ozone levels and temperature in the equatorial stratosphere. This warmer tropical stratosphere then results in a stronger latitudinal gradient and a cooler polar stratosphere (stronger polar vortex) via a modulated Brewer-Dobson cycle. The issue with these theories is that the peak levels of the aforementioned potential drivers of the solar-stratosphere connection coincide with solar max. And most recent research cite stronger drivers that do not coincide with solar max, such as geomagnetic energy and solar winds, which peak during solar flux or, about one year after solar max in terms of peak UV and TSI . (Maliniemi et al, 2014). Malimiemi et al theorize that geomagnetic energy makes its way into the polar region via the process of energetic particle precipitation, which then produces nitrogen oxides in the the upper atmosphere that have a protracted period of time to descend downward and increase ozone during the polar winter in the absence of any sunlight, which cools the stratosphere and strengthens the PV. This more closely corroborates both with other recent research, which cites drivers that do not peak at solar max as defined by UV and TSI (geomagnetic energy peaks approximately one year after solar max), as well as the research of Malimiemi et al (2014), which found that the declining phase of the sunspot cycle remarkably consistently produces the spacial pattern of surface temperature anomalies related to the positive NAO during the last 13 solar cycles" (Maliniemi et al, 2014). This makes sense since the geomagnetic energy peak that Maliniemi et al cite as the main driver behind the connection between the solar cycle and polar domain lags solar max as defined by UV, TSI and sunspots by approximately one year, which is during the declining phase that so strongly correlates with the +NAO response in their research. This is also consistent with other recent studies of seal level pressure patterns that revealed a +NAO pattern lagging solar max by approximately 2-4 years. The work of Maliniemi et al also showed that this relationship is not at all dependent on overall sunspot activity due to intra-cycle variability. 

 

Mean winter NAO index values for the four cycle phases, averaged over cycles 11 to 23. The red line represents the overall mean value of wintertime NAO (0.05). Bars represent the 95% confidence intervals.

 

Perhaps more germane within the context of the coming winter is that the study found that both the solar max and the ascending portion of the solar cycle are weakly correlated to a colder pattern redolent of the -NAO, although this is more dependent on intra-cycle variability of activity. There is no clear correlation between the solar minimum and the NAO, but perhaps modest one that perhaps a modest negative correlation.

 

 

These relationships between solar behavior and the NAO are evident in the graph above, with reds, denoting +NAO, very evident in the declining phase of the last several solar cycles. And Blue, indicative of -NAO, prevalent in the ascending portion of the cycles. Winter 2023-2024 will be in the ascending phase with the peak of solar cycle 25 anticipated within the next couple of years, thus an exceedingly strong PV is unlikely in the mean during the coming boreal winter season.

 

 

Now we can view the aforementioned EMI analogs through this solar lens in an effort to gain clarity into why the polar domain behaved in the manner that is did in each respective case.

 

In the case of the 1986-1987 winter season, given that solar minimum occurred during prior fall in September of 1986, that particular season occurred near the solar minimum at the onset of the ascending phase. This is consistent with the research marginally favoring a negative NAO.

The 1994-1995 cold season coincided with the descending phase of solar cycle 22 given that the minimum was observed in August of 1996, which also corroborates the research of Meliniemi et al that favors a +NAO during this portion of the solar cycle. Finally, the 2006-2007 winter season also took place during the descending phase of solar cycle 23, as the minimum was in December 2008. This season featured both a +NAO and exorbitantly potent PV in the seasonal mean.

 

 

 Thanks for the detailed well thought out reply! Here are my thoughts in response:

1. As you can see, I analyzed in detail just the current era of rare -NAO winters (last 44 winters) that has had 59% +NAO, 27% neutral NAO, and only 14% -NAO. This is in stark contrast to the prior 25 years of -NAO dominance with only 24% +NAO and 12% neutral NAO but 64% -NAO. With that stark a change and with a nice sample size of 44 for this current +NAO era, I figured that sticking to just these 44 winters at least for now would be best in looking ahead to the upcoming winter prospects. We're in a different NAO era and I don't know why.

2. Based on quite low sunspot activity for ALL 6 of the -NAO winters occurring during the last 44 years, it's very hard for me to accept the idea in the current era that the chance for a -NAO winter is higher near a solar max than near a min. After all, the average monthly sunspots were all low to very low: 20, 6, 12, 22, 33, and 14 for an average of only 18. This 18 compares to the longtime average monthly sunspots of 85 (based on 1900-2022 data). I mean NONE of these six low #s are anywhere near the 150+ that we're likely headed toward this winter and they're not even close to the 85 average.

3. I'm more open to the idea even in the current +NAO era that ascending may give a better chance than descending for a -NAO. After all, four of the six -NAO winters of the current +NAO era occurred during ascending: 1986-7, 2009-10, 2010-1, and 2020-1. But the thing is that these four ascending were only 4, 13, 25, and 13 months, respectively, past min. So, pretty much within only two years of the min, which in all four of these cases is significantly closer to the min than max since the subsequent max was 34, 51, 39, and a projected ~~50 months, respectively, later. So 4 vs 34, 13 vs 51, 25 vs 39, and 13 vs ~50 months, respectively. 

 So, whereas I'm very open to the possibility that chances are currently truly higher for ascending than descending, I can't at all get behind the idea of ascending nearing a max being the best shot in this era. I'm much more open to the possibility of ascending soon after min being the best shot.

 

[brooklynwx99]

3 hours ago, 40/70 Benchmark said:

If this el nino ends up with an ONI near 2.0 and the forcing makes it as far back east as about 160W, then none of this is likely to matter because we are cooked. Canonical el nino forcing that powerful would be the main driver.

I would say 140-150W… that’s where canonical forcing usually sets up 

[40/70 Benchmark]

35 minutes ago, brooklynwx99 said:

I would say 140-150W… that’s where canonical forcing usually sets up 

I say 160 because that is where 2016 was, but whatever...in that area.

[so_whats_happening]

6 hours ago, bluewave said:

While several ENSO models are going super, the subsurface is still much less impressive than at this point in 2015 and 1997.  I know it’s only a small sample size of two. But the current upper ocean heat content near +1 is much lower than the +2 values those years at this time. So not sure how we get to super status without the upper ocean heat doubling from +1 to +2. Not really seeing that yet with the trades returning and the WPAC forcing to start September. Right now looks like 1+2 may have peaked and 3, 3.4, and 4 will continue a slow but steady climb as the SST departures work west. This year could be a candidate for an early peaking event should the follow up kelvin wave activity remain as weak as it has been. Also note the lack of a WPAC cold pool which helped development in 1997 and 2016 with the very impressive WWB activity near the Dateline which has been missing this year.

 

I think the key to how warm we get may be what we see occur in nino 3 over the next month or so. It surely wont be on the same levels as 1+2 has been but just how warm that region gets will have influence on 3.4 as we go along. Again barring no major KW event happens and if one does occur just how much subsurface heating takes place? Still thinking maybe 1.7 trimonthly max with a month that can squeeze out 2.0, should be an interesting 2-3 months coming up as by November things should be pretty much settled.

I forgot what page I mentioned it on but had thought progression for each month was about 0.3C increase and so far it has held true. So back at the beginning of June I mentioned it was about a .9-1.0C in 3.4 so to keep on track it would have to go 1.2-1.3 July, 1.5-1.6 August, 1.8-1.9 September, with a peak in October around 2C then a slow demise.(Im not sure August may hit those levels though) I still can't fathom how we are to get to 2.2-2.5C if we don't pick up the pace. Dynamical models were the upper levels 2.0-2.5 range while statistical were around 1.2-1.4C in between seems to be the right path. Even if we do get to a monthly of 2C will we really have the same impact of 2C or will the impact be less. 

I wanna wait until we see maybe some MJO activity outside of near null. There is a distinct possibility that we have a brief cooling to rise again and maybe have a later peak (closer to December) which if that is the case it could very well work in favor for some fun. That would be a very 2009-10 esq scenario.

[40/70 Benchmark]

2 hours ago, GaWx said:

 Thanks for the detailed well thought out reply! Here are my thoughts in response:

1. As you can see, I analyzed in detail just the current era of rare -NAO winters (last 44 winters) that has had 59% +NAO, 27% neutral NAO, and only 14% -NAO. This is in stark contrast to the prior 25 years of -NAO dominance with only 24% +NAO and 12% neutral NAO but 64% -NAO. With that stark a change and with a nice sample size of 44 for this current +NAO era, I figured that sticking to just these 44 winters at least for now would be best in looking ahead to the upcoming winter prospects. We're in a different NAO era and I don't know why.

2. Based on quite low sunspot activity for ALL 6 of the -NAO winters occurring during the last 44 years, it's very hard for me to accept the idea in the current era that the chance for a -NAO winter is higher near a solar max than near a min. After all, the average monthly sunspots were all low to very low: 20, 6, 12, 22, 33, and 14 for an average of only 18. This 18 compares to the longtime average monthly sunspots of 85 (based on 1900-2022 data). I mean NONE of these six low #s are anywhere near the 150+ that we're likely headed toward this winter and they're not even close to the 85 average.

3. I'm more open to the idea even in the current +NAO era that ascending may give a better chance than descending for a -NAO. After all, four of the six -NAO winters of the current +NAO era occurred during ascending: 1986-7, 2009-10, 2010-1, and 2020-1. But the thing is that these four ascending were only 4, 13, 25, and 13 months, respectively, past min. So, pretty much within only two years of the min, which in all four of these cases is significantly closer to the min than max since the subsequent max was 34, 51, 39, and a projected ~~50 months, respectively, later. So 4 vs 34, 13 vs 51, 25 vs 39, and 13 vs ~50 months, respectively. 

 So, whereas I'm very open to the possibility that chances are currently truly higher for ascending than descending, I can't at all get behind the idea of ascending nearing a max being the best shot in this era. I'm much more open to the possibility of ascending soon after min being the best shot.

 

My point is more that ascending is favorable than it is that max is favorable...there really wasn't a strong signal for max. I'm also not trying to claim that exotic blocking should necessarily be expected this winter. But I do think that your focus on overall sunspot activity as a predictor for the NAO is misguided, as the research that I reviewed revealed that it's more about the trend (ascending vs descending) than min vs max. This is why we have years like 1994 and 2006 that were descending near the min with very positive NAO.

[Volcanic Winter]

15 hours ago, snowman19 said:

@Volcanic Winter Could you offer some insight into this please?

Apologies for getting to this rather late in the discussion, was going to answer in the morning but I'm having some trouble sleeping anyway. Lengthy volcano nerd post incoming, feel free to skip this post to get back to ENSO discussion .

To be honest, regarding Hunga Tonga you all are better equipped to debate its impacts than I am at this point, as it is very much not the classic 'Pinatubo style' atmospheric SO2 bomb sort of eruption that imparts a well studied downward forcing of surface temps via overloading of the stratospheric aerosol veil with sulphate. The principal driver of HTHH's impact as we know is water vapor, and that is very much an anomaly among large explosive events. While most volcanoes have a water component to the magma (it acts as a volatile), in a typical large explosive event the water vapor component is well overshadowed by SO2 and fine ash particulates. You guys know way more ocean-atmospheric physics than I do with regard to considering the water vapor impact (which will last longer than the typical SO2->sulphate production in the stratosphere; the chart @40/70 Benchmark linked shows the timeline nicely and is from a source I'm familiar with).

Couple things. Take a look at this video:

https://assets.researchsquare.com/files/rs-2044907/v1/153086f25b0f0b7d7068563b.mov

That monster column is apparently only a total volume of 1.7 cubic kilometers, while underwater PDC (pyroclastic density currents) / ignimbrite deposits totaled over 10 cubic kilometers. If this is accurate, this was a true Pinatubo sized blast and the first VEI 6 since that eruption. However, the vast majority of the gas and particulate matter went into the ocean and not the atmosphere. That monster column? Mostly boiled seawater... 1.7 cubic kilometers would be a small VEI 5 and not typically the sort that would have a measurable climate impact, and that checks out with the measured atmospheric SO2 pulse from the eruption (which was well below even El Chichon in the 1980's). Pinatubo was over 10 cubic kilometers all blasted straight up.

Source for the above:

https://assets.researchsquare.com/files/rs-3000198/v1/95ad0f06-876f-487c-ba2b-fed11310ce6a.pdf?c=1686242395

--

I believe you guys were discussing if HTHH's plume would've crossed hemispheres and frankly it's a good question and the answer varies from eruption to eruption. Ice cores between Greenland and Antarctica often show different levels for the same eruption depending on where the eruption took place and what the atmospheric conditions were like at the time of the eruption, which matter as far as dispersal of the aerosols. Generally big eruptions do cross hemispheres, but it really varies significantly and usually the hemisphere the eruption occurred in receives more of the particulate load. If we're talking only 1.7 cubic kilometers (which is only slightly larger than Mt St Helens 1980) of atmospheric ejecta, it really is irrelevant because it's not large enough to matter. It all goes back to the water vapor, as that is a separate measurement and would be the reason the eruption plume in the above video is so monstrous.

One thing is for certain, I would not want to have been a fish near HTHH when it detonated. 10 cubic kilometers of PDC deposits erupted in just a couple hours is a massive and extremely intense event. It just beat the hell out of the seafloor more than the atmosphere. Seriously, just because most of it went into the ocean, this was still a once in a thousand year caldera-forming eruption from HTHH and is easily one of the most intense eruptions witnessed by man, though Krakatau and Novarupta were 3x larger, and Tambora was as much as 15x larger.

But yeah, go back to the water vapor. I read something like 1/10th of the total that normally resides up there was ejected in the eruption, and that it could remain for up to 5-10 years? That's definitely what I would focus on, because that's the 'story' of the HTHH eruption.

 

[snowman19]

I think the key to how warm we get may be what we see occur in nino 3 over the next month or so. It surely wont be on the same levels as 1+2 has been but just how warm that region gets will have influence on 3.4 as we go along. Again barring no major KW event happens and if one does occur just how much subsurface heating takes place? Still thinking maybe 1.7 trimonthly max with a month that can squeeze out 2.0, should be an interesting 2-3 months coming up as by November things should be pretty much settled.
I forgot what page I mentioned it on but had thought progression for each month was about 0.3C increase and so far it has held true. So back at the beginning of June I mentioned it was about a .9-1.0C in 3.4 so to keep on track it would have to go 1.2-1.3 July, 1.5-1.6 August, 1.8-1.9 September, with a peak in October around 2C then a slow demise.(Im not sure August may hit those levels though) I still can't fathom how we are to get to 2.2-2.5C if we don't pick up the pace. Dynamical models were the upper levels 2.0-2.5 range while statistical were around 1.2-1.4C in between seems to be the right path. Even if we do get to a monthly of 2C will we really have the same impact of 2C or will the impact be less. 
I wanna wait until we see maybe some MJO activity outside of near null. There is a distinct possibility that we have a brief cooling to rise again and maybe have a later peak (closer to December) which if that is the case it could very well work in favor for some fun. That would be a very 2009-10 esq scenario.

I think it peaks a little later, December would be my guess. If I had to make an early guess right now, I can see the trimonthly ONI go something like +2.2C, +2.3C, +2.1C for NDJ. The models show that this Nino is going to be very slow to weaken after it peaks, through JFM. I also agree with Griteater that this event stays east-based/EP

[40/70 Benchmark]

6 hours ago, Volcanic Winter said:

Apologies for getting to this rather late in the discussion, was going to answer in the morning but I'm having some trouble sleeping anyway. Lengthy volcano nerd post incoming, feel free to skip this post to get back to ENSO discussion .

To be honest, regarding Hunga Tonga you all are better equipped to debate its impacts than I am at this point, as it is very much not the classic 'Pinatubo style' atmospheric SO2 bomb sort of eruption that imparts a well studied downward forcing of surface temps via overloading of the stratospheric aerosol veil with sulphate. The principal driver of HTHH's impact as we know is water vapor, and that is very much an anomaly among large explosive events. While most volcanoes have a water component to the magma (it acts as a volatile), in a typical large explosive event the water vapor component is well overshadowed by SO2 and fine ash particulates. You guys know way more ocean-atmospheric physics than I do with regard to considering the water vapor impact (which will last longer than the typical SO2->sulphate production in the stratosphere; the chart @40/70 Benchmark linked shows the timeline nicely and is from a source I'm familiar with).

Couple things. Take a look at this video:

https://assets.researchsquare.com/files/rs-2044907/v1/153086f25b0f0b7d7068563b.mov

That monster column is apparently only a total volume of 1.7 cubic kilometers, while underwater PDC (pyroclastic density currents) / ignimbrite deposits totaled over 10 cubic kilometers. If this is accurate, this was a true Pinatubo sized blast and the first VEI 6 since that eruption. However, the vast majority of the gas and particulate matter went into the ocean and not the atmosphere. That monster column? Mostly boiled seawater... 1.7 cubic kilometers would be a small VEI 5 and not typically the sort that would have a measurable climate impact, and that checks out with the measured atmospheric SO2 pulse from the eruption (which was well below even El Chichon in the 1980's). Pinatubo was over 10 cubic kilometers all blasted straight up.

Source for the above:

https://assets.researchsquare.com/files/rs-3000198/v1/95ad0f06-876f-487c-ba2b-fed11310ce6a.pdf?c=1686242395

--

I believe you guys were discussing if HTHH's plume would've crossed hemispheres and frankly it's a good question and the answer varies from eruption to eruption. Ice cores between Greenland and Antarctica often show different levels for the same eruption depending on where the eruption took place and what the atmospheric conditions were like at the time of the eruption, which matter as far as dispersal of the aerosols. Generally big eruptions do cross hemispheres, but it really varies significantly and usually the hemisphere the eruption occurred in receives more of the particulate load. If we're talking only 1.7 cubic kilometers (which is only slightly larger than Mt St Helens 1980) of atmospheric ejecta, it really is irrelevant because it's not large enough to matter. It all goes back to the water vapor, as that is a separate measurement and would be the reason the eruption plume in the above video is so monstrous.

One thing is for certain, I would not want to have been a fish near HTHH when it detonated. 10 cubic kilometers of PDC deposits erupted in just a couple hours is a massive and extremely intense event. It just beat the hell out of the seafloor more than the atmosphere. Seriously, just because most of it went into the ocean, this was still a once in a thousand year caldera-forming eruption from HTHH and is easily one of the most intense eruptions witnessed by man, though Krakatau and Novarupta were 3x larger, and Tambora was as much as 15x larger.

But yeah, go back to the water vapor. I read something like 1/10th of the total that normally resides up there was ejected in the eruption, and that it could remain for up to 5-10 years? That's definitely what I would focus on, because that's the 'story' of the HTHH eruption.

 

Yes...pretty much echoes what I said. Most of what was released into the atmosphere was water vapor, not S02, and thus not very impactful on the NH PV...what impact there was should have already been observed last winter.

And the impact of these events is over simplified..it depends on location and global circulation patterns as to how they impact the poles, if at all.

Have you read about how some eruptions back in the 1960s and in 2009 even augmented a -AO/NAO response? I am not implying that will happen this year....just drawing it to your attention because its interesting.

[roardog]

17 minutes ago, 40/70 Benchmark said:

Yes...pretty much echoes what I said. Most of what was released into the atmosphere was water vapor, not S02, and thus not very impactful on the NH PV...what impact there was should have already been observed last winter.

And these events are over simplified..it depends on location and global circulation patterns as to how they impact the poles, if at all.

Have you read about how some eruptions back in the 1960s and in 2009 even augmented a -AO/NAO response? I am not implying that will happen this year....just drawing it to your attention because its interesting.

I’ve read that it’s theorized that major high latitude eruptions can lead to -AO/NAO while the low latitude eruptions often lead to +AO/NAO. Of course we’ve also all heard the theory about low sea ice leading to high latitude blocking and that hasn’t been working out too well in the last decade. 

[40/70 Benchmark]

13 minutes ago, roardog said:

I’ve read that it’s theorized that major high latitude eruptions can lead to -AO/NAO while the low latitude eruptions often lead to +AO/NAO. Of course we’ve also all heard the theory about low sea ice leading to high latitude blocking and that hasn’t been working out too well in the last decade. 

I don't this event is having much impact at all.

[Volcanic Winter]

1 hour ago, 40/70 Benchmark said:

Have you read about how some eruptions back in the 1960s and in 2009 even augmented a -AO/NAO response? I am not implying that will happen this year....just drawing it to your attention because its interesting.

So I think it’s extremely fascinating, but not something I’m intimately familiar with. I’m playing catch up to all of you regarding teleconnection meteorology. 

I still need to look into what we discussed and the paper you sent me, but it’s definitely intriguing to me. 

You know, I’m so used to looking into the large events that it’s easy to pass up clusters of smaller events, and 2008-2009 had a significant cluster of VEI 4 eruptions between .1 - 1 cubic kilometers (Okmok, Chaiten, Kasatochi, and Sarychev Peak, with Eyllafjallajökull occurring in 2010 which was a very ash rich but relatively small VEI 4). Honestly 2008-2011 was a very active period volcanically, including 2011’s Puyehue Cordon Calle eruption (my forum avatar, GORGEOUS eruption) which is commonly referenced as a baseline VEI 5 but IMO is better categorized as a high end VEI 4, but that is semantic as the difference between .9 cubic kilometers and 1 is negligible. 

I’m going to look further into this, thanks for mentioning. 
 

Edit: One area of interest to me for clues is the Little Ice Age. It is commonly referenced that volcanism played a large role in driving this period (along with the Maunder Minimum, perhaps agricultural factors I’ve read, etc), but we know that typically even very large eruptions only impact the climate for several years. Certainly not decades to centuries. While it’s true there were many VEI6 and large 5’s throughout this period, along with Tambora’s VEI 7 (and the Samalas VEI 7 in the 13th century which was basically one island over from Tambora, interestingly), this really wasn’t anything too unusual. Every thousand years will see 2-3 VEI 7 or borderline 7’s, on average. You’ll get something like 2-4 VEI 6’s or borderline 6’s per century. The LIA had big volcanism, but there’s always big volcanism lurking just outside the timespan of a human life. 

There had to be self reinforcing positively interfering mechanisms at play throughout this period, possibly a cooling of the North Atlantic along with long stretches of -NAO/AO cooling North America and Europe? While glaciers advanced in many locations throughout the LIA, I still understand it to be a regional phenomenon. 

Just a thought that came to mind based on your comment. 

Volcanism plays an enormous role in the ebb and flow between hothouse and stadial climate states as well, with ‘flood basalts’ being one of the main drivers of paleoclimate hothouses. But these eruptions are on a scale that is unfathomable over long periods of time (100,000+ cubic kilometers over thousands of years), and occur with many 10’s of millions of years between. They’re also more common when the continents are in a conjoined state as it helps build the pressure needed to contain a mantle plume and allow an eruption that size to occur. I digress , the point is simply that volcanism and earth’s climate are highly linked throughout time. And I think it’s certainly possible there’s small scale stuff happening (ie teleconnection forcing) like what you’re touching on. 

[GaWx]

11 hours ago, 40/70 Benchmark said:

My point is more that ascending is favorable than it is that max is favorable...there really wasn't a strong signal for max. I'm also not trying to claim that exotic blocking should necessarily be expected this winter. But I do think that your focus on overall sunspot activity as a predictor for the NAO is misguided, as the research that I reviewed revealed that it's more about the trend (ascending vs descending) than min vs max. This is why we have years like 1994 and 2006 that were descending near the min with very positive NAO.

 I'd love to end up wrong in not going with the first -NAO winter while average+ sunspots since 1978-9 and only 2nd -NAO of last 13 winters. But for now at least, I'm predicting either neutral NAO (i.e., between -0.25 and +0.25) or +NAO. Of course, even with a neutral NAO, there can easily be one solid -NAO month of the winter as occurred in 2005-6 (Feb), 2002-3 (Dec), 2001-2 (Dec), 2000-1 (Dec), 1997-8 (Dec), 1996-7 (Dec), 1985-6 (Feb), 1981-2 (Jan), and 1979-80 (Jan). So, that makes 9 out of the 12 neutral NAO winters having one solid -NAO month of the three. Also, 1989-90 (Dec) and 1982-3 (Feb) actually each had a solid -NAO month despite being an overall +NAO winter.

[40/70 Benchmark]

3 minutes ago, GaWx said:

 I'd love to end up wrong in not going with the first -NAO winter while average+ sunspots since 1978-9 and only 2nd -NAO of last 12 winters. But for now at least, I'm predicting either neutral NAO (i.e., between -0.25 and +0.25) or +NAO. Of course, even with a neutral NAO, there can easily be one solid -NAO month of the winter as occurred in 2002-3 (Dec), 2001-2 (Dec), 2000-1 (Dec), 1997-8 (Dec), 1996-7 (Dec), 1985-6 (Feb), 1981-2 (Jan), and 1979-80 (Jan). So, that makes 8 out of the 12 neutral NAO winters having one solid -NAO month of the three. Also, 1989-90 (Dec) and 1982-3 (Feb) actually each had a solid -NAO month despite being an overall +NAO winter.

Yea, like last winter. I could def. see that...I'm not favoring a deeply negative NAO necessarily.

[GaWx]

3 minutes ago, 40/70 Benchmark said:

Yea, like last winter. I could def. see that...I'm not favoring a deeply negative NAO necessarily.

 Good point. Indeed, if I include March, that adds as you said 2022-3 (+NAO winter), 2017-8 (+NAO winter), 2012-3 (neutral NAO winter), 2004-5 (+NAO winter), and 1980-1 (+NAO winter). So, there'd still be a lot of hope for one solid -NAO month of DJFM even without an overall -NAO winter.

[snowman19]

41 minutes ago, GaWx said:

 Good point. Indeed, if I include March, that adds as you said 2022-3 (+NAO winter), 2017-8 (+NAO winter), 2012-3 (neutral NAO winter), 2004-5 (+NAO winter), and 1980-1 (+NAO winter). So, there'd still be a lot of hope for one solid -NAO month of DJFM even without an overall -NAO winter.

The Nino has gone strong in region 3.4 on the CRW (over +1.5C), yesterday’s OISST update wasn’t far behind at over +1.44….. 

[George001]

4 minutes ago, snowman19 said:

The Nino has gone strong in region 3.4 on the CRW (over +1.5C), yesterday’s OISST update wasn’t far behind at over +1.44….. 

Super by October? 

[40/70 Benchmark]

August ENSO Update & Potential Extratropical Pacific Analogs for Winter 2023-2024 | Eastern Mass Weather