Volcanic Winter 2022?

[Tallis Rockwell]

For some who don't know, Tonga produced a huge eruption around a VEI 5 or 6, and if we find that this volcano has ejected a significant portion of SO2, volcanic winter is on the cards!

[roardog]

7 minutes ago, Tallis Rockwell said:

For some who don't know, Tonga produced a huge eruption around a VEI 5 or 6, and if we find that this volcano has ejected a significant portion of SO2, volcanic winter is on the cards!

Doesn’t a “volcanic” winter have a tendency to produce a positive AO and positive NAO with mild mid latitudes? I don’t think most people posting here would like that. 

[Tallis Rockwell]

Almost all known major volcanic winter events produced mild winters so a lot of winter weather enthusiasts are going to be mad,

[Volcanic Winter]

Tallis, I recognize you from Volcanocafe! Nice to see you here man. 
 

And yes, this eruption did appear to be large enough to enact measurable climate forcings but we need more data on the overall volume and amount of SO2 injection. 
 

Also, outside of very, very large eruptions (7+?), aren’t the climate forcings from large plinian eruptions usually restricted to the hemisphere they occurred in (aka Southern)? 

[Volcanic Winter]

Regardless I still can’t believe I woke up yesterday to news of an eruption that may be around the size of Pinatubo, out of nowhere. 
 

Leads more credence IMHO to another transient tropical blast being behind the mystery eruption of 1808/9 and perhaps other unknown climate altering eruptions throughout history. 

[Volcanic Winter]

11 hours ago, roardog said:

Doesn’t a “volcanic” winter have a tendency to produce a positive AO and positive NAO with mild mid latitudes? I don’t think most people posting here would like that. 

Well, other large climate altering eruptions have caused cold temperature anomalies and heavy precipitation throughout North America and Europe. It’s highly dependent on many factors, but there’s no assurance here that such an event will be mild in the mid latitudes (and that’s just going off recorded history). 
 

I do think it’s more likely whatever occurs from this is restricted to the Southern Hemisphere, or at least is strongest felt in the Southern Hemisphere. But I’m not 100% on that. 
 

Edit: Not specific to winter, just for the year overall. I think the worst of “volcanic winters” is usually during summer. But I’ve read plenty about very cold winters following large eruptions, unless those winters were going to be cold regardless of the eruption? Tallis you know more than me so feel free to expand. 
 

Can’t believe we’re even talking about this honestly. 

[Random Chaos]

1 hour ago, Volcanic Winter said:

Tallis, I recognize you from Volcanocafe! Nice to see you here man. 
 

And yes, this eruption did appear to be large enough to enact measurable climate forcings but we need more data on the overall volume and amount of SO2 injection. 
 

Also, outside of very, very large eruptions (7+?), aren’t the climate forcings from large plinian eruptions usually restricted to the hemisphere they occurred in (aka Southern)? 

Volcano Cafe is great! Always read it after an event, mostly lurker there but occasionally post. Got me to check my weather station for the shockwave:

 

[Tallis Rockwell]

4 hours ago, Volcanic Winter said:

Regardless I still can’t believe I woke up yesterday to news of an eruption that may be around the size of Pinatubo, out of nowhere. 
 

Leads more credence IMHO to another transient tropical blast being behind the mystery eruption of 1808/9 and perhaps other unknown climate altering eruptions throughout history. 

Hello! I glad to see another volcano fanatic! Unfortunately, the eruption only released 0.4 Tg of SO2 so no substantial climate effects are likely.

https://twitter.com/simoncarn/status/1482612959104974848

[Volcanic Winter]

Yup, I’ve since saw that but hadn’t heard at the time I made my comment. Much too low to have any impacts, though the blast itself was remarkable. 

[Tallis Rockwell]

8 hours ago, Volcanic Winter said:

Yup, I’ve since saw that but hadn’t heard at the time I made my comment. Much too low to have any impacts, though the blast itself was remarkable. 

We'll have to keep waiting for that awesome volcanic winter ):

[Roger Smith]

There is some chance of the Tonga eruption having an impact on the winters of 2022-23 and 2023-24. Following Tamboro (Apr 1815) there was a very cold period throughout the northern hemisphere setting in around the winter of 1815-16 and reaching its most anomalous levels in the "year without a summer" of 1816. Winter 1816-17 where records exist was not exceptional, in fact considerable mild weather was experienced in some winters 1817 to 1819, but winter 1820 was harsh. Then after Krakatoa (1883) several years were very cool but what contaminates that is the fact that 1883 was already running very cold before the eruption (March 1883 in particular set many cold records). The greatest effect from Krakatoa looks to be around the winter of 1884-85. Pinatubo (1991) was a less severe volcanic eruption but is widely credited (whether right or wrong) with the cool summer of 1992. Winter 1992-93 was quite a cold one, 1993-94 even colder. For the size of the dust veil it would seem that Pinatubo should not be given all the credit for those cold winters, however. 

It takes several months for a tropical dust veil to spread out over the mid-latitudes and this one was further south of the equator than the other examples. If the dust veil is comparable to Krakatoa then we should see some effects from it. However, the current La Nina could flip to some kind of El Nino pattern and that might offset, at least for a while. 

Is the Tonga dust veil considered similar to Krakatoa, or more like Pinatubo? 

There was also a volcanic connection postulated between eruptions in Iceland in 1783 and the cold winter of 1783-1784. 

[Volcanic Winter]

Tonga was much more steam laden / phreatic than either Pinatubo, Krakatoa, or Tambora; all three ejected far more tephra and sulfur. 
 

The size and intensity of the Tonga blast came largely from catastrophic depressurization of supercritical water or highly pressurized steam, flashing over into an intense point explosion. It did vaporize the majority of the island and likely will reach mid to high end VEI5 all said and done, but it’s unlikely to have a major climate cooling impact as the other three mentioned did. They were substantially larger in terms of ejected volcanic material hitting the stratosphere. 
 

With that said, a ~ -0.5C anomaly forcing in the Southern Hemisphere is still possible, but global effects are unlikely. Just wasn’t big enough in the sense of total material hitting the upper levels of the atmosphere as a huge portion of the blast was stream. No doubt the explosion was insane and the overall size of the mushroom cloud implied a much bigger eruption than what it will likely end up as. 
 

I have seen the 400,000t sulfur measurement called into question, and am personally wondering how a portion of the eruption column reaching the mesosphere at over 55km may ultimately affect things, but in general a smallish negative forcing in the Southern Hemisphere should be about the worst potential impact of this.  
 

Also should be noted the debate over the actual size of the eruption is still very much ongoing. A paper was just released characterizing the blast as a VEI6 which can have a much greater climate impact, but it depends on how much material hit the stratosphere (and beyond), some of which still seems to be the subject of debate. 

[Volcanic Winter]

It’s still very much a monumental eruption that will move volcanology forward. It was also a one in a thousand year event for the Honga Tonga Honga Ha’apai caldera. 

[bdgwx]

0.4 MtSO2 probably isn't going to have a large effect on global average temperatures. I'm not sure we'd be able to detect it especially given that RSS and UAH have monthly uncertainties of about ±0.2 C. Of course, if scientists do determine that there was significantly more SO2 released than obviously there would be a more significant impact on global average temperatures as well.