Details on the Kasatochi eruption

This article sums up a lot of the events that led up to the Kasatochi (Alaska) eruption last week from the point of view of the biologists on the island itself right before it erupted. There are some great descriptions of the whole island shaking for 10 minutes, and they also offer some exciting new details such as this:

"Jeff Williams, a biologist for the maritime refuge, sailed by the island on the refuge boat the Tiglax and said the island has a new shape; what were steep cliffs rising from the ocean on the island's east and west sides now appear to be long, gradual slopes."

That would imply to me that the eruption has produced a lot of pyroclastic material that now lies as an apron of material around the vent - much like a river delta or alluvial fan of volcanic material. Most likely, this material will be quickly eroded if it is merely piles of loosely consolidated pumice and ash, but at least for the time being, Kasatochi has added some valuable oceanside real estate to the island.

More like this

I am a healthcare professional. Unlike many of my collleagues, I am fully aware that I do not know anything remotely near "everything." The Jesus / God Complex has not and never will infect me: Edifying, no? Modest docs do exist. The pompous ones should be sent to Antartica without proper equipment.

I ask you: Would you care to share with me / us your informed speculations about any climactic impact in the ST and LT (if of any sig.) that may result as a consequence of this rather impressive eruption / series of eruptions in the Aleut. Chain? The sources I have perused, as an educated layperson, are ridiculously conflictual. Some argue that eruptions of equiv. magnitude in the S Hem. have much greater climactic Global impact than those in the N. Others dismiss that as bunk, and are divided, some stating that this eruption will have no sig. impact Globally and it wouldn't had it been in the S. Hem., and others screechingly disagreeing that the impact of this eruption (or series thereof) will have quite an impact. Others beg to differ and write that, in fact, there should be impact in the N latitudes (roughly 25-64N they claim), but it will be, at least initially, in the form of a warmer winter already this year. Fine bunch of theoreticians, indeed. Geology, climatology, etc. have always interested me tremendously, and I am finding the latest output of the various experts and "experts" quite baffling.

If I got such consults on a seriously ill patient, s/he would likely die immediately from the mere shock of hearing such insanely differing opinions voiced with such majestic certainty.

Of course, with the friendly volcanoes, lives are in the balance, too, far more than in my little ditty! I know all too well that ambiguity is just a fact of life in any sophisticated field of inquiry, but the above nuttiness (and I've only given a few sample "prognoses") is beyond the pale. Or maybe not?

You strike me as having a more balanced perspective, probably as a result of having far more education than a BS in meteorology / geology, etc. (relax, Bachelor-level meteorologists et al., you have plenty to say here, too, but not as much). You also have a sense of humour, a very good thing for your health and that of your readers, to a lesser degree. No "chicken little" prognostications are coming from you as of yet, and I like that. So what's your take, Dr. Klemetti, on the above eruption in the climate domain?

~Thank you.
Doc Hill

By Dr. G. Hill (not verified) on 14 Aug 2008 #permalink

I am not an expert, but I would doubt this would have much of an impact on the climate. According to NASA, the Kastachi eruption cloud contained about 1.5 million tons (1.36 million tonnes) of sulphur dioxide, and is one of the largest volcanic SO2 clouds scientists have tracked since Chileâs Hudson volcano erupted in 1991. However, that is far short of the 20 tons of SO2 that Pinatubo injected into the atmosphere in 1991, which did have a short term impact on the climate.

Thanks, Brian.

Yes, per the info you provide, Kasatochi belched ~ 7.5% of the SO2 Pinatubo so generously shared with our atmosphere back in 1991. And you also say that the latter's effect on climate was "short term." So Kasatochi's eruption was a mere burp in the scheme of things.

Seems like Kasatochi et al. will have to do better in the future--which of course I would not want--in order to impact global climate even in the ST. I do hope that the folks out in the Aleut. Chain are doing okay, as okay as can be most optimistically expected. I need to read up on that.

I appreciate you taking the time to share this data with me and anyone else who might've been wondering.


Doc Hill

By Dr. G. Hill (not verified) on 15 Aug 2008 #permalink

In my educated layman's opinion, Chaiten is the one to watch. No one seems to know what it will do next and the eruption has lasted 3 months already.

And as for the wildly differing opinions, you have to view them in the light of the AGW 'hysteria', which down plays all climate impacts except GHGs. This is despite the historical record showing significant short term climate impacts from volcanic eruptions lasting up to several years. My suspicion is that the differing views you found are a proxy fight over GHG AGW.

And also, Pinatubo did indeed emit more SO2 than any recent volcanic eruption, but El chichon had a significantly larger climate impact, so there is more to the story than SO2.…

Thank you, Philip B.

Clearly your educated layman's opinion leans more toward the educated in this domain than the layman. Politics does have a tendency to muddy the waters of scientific inquiry. All sorts of agendas, from getting that coveted tenure to pushing some popular "truism" or other all fall into this nasty meatgrinder. I am sure that all but the politicians (I don't like them) would agree on that one. The AGW 'hysteria' you mention, "which downplays all climate impacts except GHGs" sounds like an interesting Tree of Knowledge and possible Silliness to climb, with your very helpful input. So there's more to the story than SO2. I thought so, but, unlike you, didn't quite know how to argue that point. You're a good tour-guide.

So I thank you!

Doc Hill

By Dr. G. Hill (not verified) on 16 Aug 2008 #permalink