Though the eruption at Kilauea shows no signs of stopping, it really is dropping down the news agenda and so, rather than repeat myself, I shall drop it down the agenda on the digest, too, although I certainly won’t be pretending it’s gone away. It hasn’t, and it continues to be hugely significant, not least for those whose homes remain under threat.
But there’s plenty more going on in the world, and plenty more to say about volcanoes. This week I’m picking up the volcano theme with a quick look at some fascinating research on what’s going on under New England and a roundup of volcanic activity over centuries.
New England: New Volcanic Hotspot!
I’m sorry for the sensationalist strapline (and the exclamation mark). It’s meant to be ironic and it really isn’t sensationalist at all by comparison with some of the editorial summaries of current research that are flying around. What Fox News (sorry again) describes as “A new super volcano…brewing under Massachusetts, Vermont and New Hampshire” may or may not turn out to be as cataclysmic for our planet as the headline suggests, but one thing is certain. None of us will be around to see it.
Stripping away the sensationalism, the piece of research in question is fascinating for anyone with an interest in volcanoes or in long term earth processes. In a nutshell, a team from Rutgers University have used the seismic signals from earthquakes to detect something curious and unexpected below New England.
Seismic waves move at different speeds according to the nature of the rock and the scientists have identified what the university’s press release describes as: “an enormous mass of warm rock is rising beneath part of New England”.
What’s significant about this is not the imminence or otherwise of any volcanic eruption, but that it allows us to look for the first time at the very early stages in the development (potentially) of a super plume or volcanic hotspot. (I should add that this is my interpretation, and the press release and the abstract of the report are careful not to use that term, preferring instead to describe it as an “upwelling” — or even a “hypothesised upwelling”.)
Apart from the rare, very small, earthquake, New England is tectonically stable, but as the study’s lead author observes, the identification of this feature “challenges the established notion of how the continents on which we live behave.” It’s unusual and raises more questions than answers.
By calling it a superplume, or even a potential superplume, perhaps I’m as guilty as any of the news media of adopting a sensational, though perhaps more accessible, term. And the report makes it clear that this feature is nothing like the scale of Yellowstone. Of course, if this upwelling of magma does ever reach the surface there could indeed be cataclysmic impacts — but if that happens it’ll be many millions of years in the future.
Volcanic Activity: Is It Increasing?
The news media have talked a lot about volcanoes recently. I’ve talked a lot about them. Does that mean that volcanic activity is increasing?
Analysis inevitably lags behind news media reporting and requires careful consideration and qualification. For example, we’re all aware of the current Kilauea eruption and, if asked, might suggest it’s lasted a month to date, but the current eruption of Kilauea has been going on since 1982.
I’d like, therefore, to draw your attention to analyse which I came across this week on the Smithsonian Institution/National Museum of National History’s Global Volcanism Program, which is one of my go-to websites for all things volcanic. I don’t know the date of its publication though the data used go back only as far as 2009, but it nevertheless produces a long-term analysis of volcanic activity worldwide.
I’m wary of linking to it, because the website seems (rightly) cautious of the data being misinterpreted, requesting readers “not reproduce the figures below without all of the accompanying analysis and proper citation”. (You will find a link to it in the resources section.) In other words, there are plenty of caveats.
So, without reproducing any of the figures, I will reproduce its conclusions. One of them reinforces a point I have repeatedly made, that media prominence given to an eruption is related to the numbers affected by it. The example given is that: “The 1980 St. Helens eruption… generated enormous media attention, while the remarkably similar 1956 eruption of Bezymianny in sparsely populated Kamchatka, in which no lives were lost, was hardly noticed by the world press”.
The article notes that there are trends in volcanism as some areas become periodically more active, bit overall: “all major trends in our recent volcanological record can be reasonably explained by historical events, technological changes, and exploration influences. The apparent increase in activity reflects increases in people living near volcanoes to observe eruptions and improvements in communication technologies to report those eruptions. The best evidence that these trends are apparent rather than real comes from the record of large eruptions, whose … constancy over the past two centuries is a better indicator of the global frequency of eruptions than the improved reporting of smaller eruptions”.
Because there’s little new to say about Kilauea, it becomes instantly less newsworthy. That doesn’t mean activity has ceased.
Last week I mentioned the ongoing hazards — lab flows, volcanic gases and ash and other emissions such as Pele’s hair. All of these continue more or less as before, although the latest USGS update indicates that sulphur dioxide emissions at the summit have dropped, although levels of volcanic gases remain high at the most active fissure, Fissure 8.
It may be that this continues until this particular phase of the eruption peters out, or there may be further developments. In the meantime, the island of Hawaii keeps on growing.