Tongan eruption disrupting flights

The eruption of Hunga Tonga Hunga Ha'apai volcano in Tonga looks to be a big one. Keleti Mafi, head of the Tongan geological service, calls this "a very significant eruption, on quite a large scale", which is no surprise considering some of the spectacular picture we saw of the eruption yesterday. In fact, the eruption is big enough that it has disrupted air traffic over Tonga, as Air New Zealand has issued a warning about the ash column - an ash column that has reached over 15,000 meters/50,000 feet! Luckily for the residents of Tongatapu, a mere 10 kilometers 50 km to the southwest SSE from the volcano, so far the trade winds have pushed most of the ash and volcanic emissions away from the island.

For those of you unfamiliar with the hazards that ash poses to aircraft, I'll point you to an excellent USGS report on the subject. With large eruption like the one we're seeing in Tonga, accurate predictions of ash column height and dispersal are vital in order to keep air traffic safe.

From the Auckland Art Gallery Collection

As for the eruption itself, it appears that some precursor seismicity was felt on the islands around the volcano, before the first sighting of the plume was made. Mafi mentions that there might actually be two vents involved (although this is unconfirmed) and that this eruption looks to be bigger than the last large eruption in Tonga in 2002. Fiji should expect large amounts of pumice to wash up on its shores in the near future as well. Tongan officials will "visit the area" (not sure how close that means) and fisherman have been told to stay away from the erupting volcano.

These types of eruption, although impressive, are not unheard of in the area. Just wandering around the interweb last night I found this amazing painting (see above) of an eruption in Tonga in 1886. The painting looks very similar to the pictures we've seen so far of the 2009 eruption (top).

More like this

According to Google Earth, Nukuʻalofa is 40 miles (not km) from Hunga Tonga Hunga Ha'apai and it is SSE of the volcano, not SW. Some of the news reports I saw gave the incorrect 10km figure.

Thanks Bobs for the correction. I have fixed it in the article. I really need to learn to doublecheck the geography presented in article because a lot of the time, they're lucky to be on the right planet let alone accurately locating an island in the Pacific.

My first thought: How much influence does this have on global warming?

If someone could help me find **science** on the internet that talks about the role of volcanic eruptions as large as this in adding to the greenhouse effect and/or blocking sun energy, I'd be most appreciative.


By CockroachesWillRule (not verified) on 18 Mar 2009 #permalink

Maybe I don't want to wade into this fray, but regarding volcanic eruptions and "global warming". The current trend of warming average temperatures worldwide cannot be explained by volcanic eruptions. Yes, volcanic eruptions release an awful lot of greenhouse gases like carbon dioxide, sulfur dioxide, carbon monoxide, water and the like, and yes, they can have a profound effect on climate (typically by cooling it), but ... but ... volcanic eruptions have been going on at (most likely) roughly the same rate worldwide for millions and millions (and billions?) of years. So, imagine you have a bucket that fills halfway with rainwater (that represent volcanic eruptions) and then you stick a hose in the bucket (representing manmade greenhouse gas emissions) and turn on the spigot. The bucket will runeth over ... but not because of the rainwater (volcanic eruptions). They are a baseline that is punctuated by large events, but we are, by no means, living in a time of increased volcanic activity over the past few hundred years. The USGS has estimates that volcanoes produce ~1% of all modern carbon dioxide emissions (an important, but not the only greenhouse gas).

If you want information on exactly what volcanic gas emissions do to the climate, check out this USGS report.

With the large amount of air travel from N. America to Austral-Asia, these western Pacific arc volcanoes pose a significant hazard. A recent example of this was the eruption of Anatahan in 2003. This current eruption of Hunga Tonga Hunga Ha'apai also illustrates that some of these volcanoes are submarine, yet shallow enough to have a significant eruption column and cloud. Needless to say, these volcanoes are generally less studied than their counterparts on islands.

Silly question: would this have any impact on turbo-prop aircraft? (e.g. used in the internal airline flights within the country.)

There is local reportage in the Tonga newspaper here, for those interested: (Includes some fairly dramatic photos.)

By Heraclides (not verified) on 19 Mar 2009 #permalink

Not looking to debate. Your link gets me started to answering the questions I have.


By CockroachesWillRule (not verified) on 19 Mar 2009 #permalink

would be interested in seeing some underwater pics/video of this explosion what a grand opportunity.

Things you brought up a lot of sense. However, consider this, suppose you included a little bit more? I am talking about, I don't want to tell you how you can write ur blog, however what if you actually added something which can certainly get people's particular attention? Just simply like a video or even a picture or perhaps few for getting viewers excited about what you are talking about.