Looks like shifting wind + gas plumes = not fun out at Kilauea. Enough that the park closed completely yesterday, and several of the surrounding communities were put under voluntary evacuation notice. Shifting winds are blowing the gas plume emanating from Halema’uma’u crater out over the inhabited parts of the park and into local communities, which usually don’t have to deal with vog, or volcanic fog. Here’s part of the story from the Honolulu Advertiser:

“That evacuation included the Volcano House hotel within the park, with guests at the hotel moved to the Naniloa Volcanoes Resort in Hilo, [Big Island Mayor Harry] Kim said. He said staffing at the park would be limited to required personnel only.

Civil defense officials at 9 p.m. last night announced voluntary evacuations for five communities northeast of Halema’uma’u crater as sulfur dioxide fumes in the area are expected to intensify today.

The voluntary evacuation advisory covered the Mauna Loa Estates, Ohia Estates and Volcano Golf Course subdivisions as well as the Volcano Village and Keauhou Ranch areas.”

Here’s another comment from Kim in the AP:

“As far as we know the number was light because the sulfur dioxide levels really did not materialize to the degree that was much anticipated,” Hawaii County Mayor Harry Kim said. “What did happen during the day is that we did have some … brief periods of high levels of sulfur dioxide in the affected areas, mainly in the national park areas.”

Vog is nasty stuff. Usually it’s Kona that has the most problems with it, enough so that they put out daily advisories of vog levels, much like air quality notices or pollen counts on the mainland. On my trips, it was barely noticeable, which was quite lucky – although that’s not to say that I didn’t have encounters with volcanic gases.

One part of my field course the second time around was to learn how to sample volcanic gases; to do this, we first had to familiarize ourselves with the hazards involved. The instructor filled up some balloons with samples of CO2, SO2, and H2S. The CO2 was, naturally, undetectable; the SO2 was a little stinky, but no more than, say, exhaust from a car engine. The H2S, though, was like a kick to the face. It’s extremely acidic, smells horribly like rotton eggs and made pretty much everyone screw up their eyes and cough for the next five minutes. Going out to the sampling sites, we all wore gas masks, and after an hour or so even the hardiest of us was dealing with the coughing and stinging eyes. At one point, I couldn’t see or stop coughing long enough to breathe – and that was with a heavy-duty gas mask with fresh filters. (I suspect this was mostly because of very high concentrations of SO2, since enough H2S will kill you, but high levels of pretty much any acidic sulfur gas are not fun.)

Hopefully the hazardous conditions won’t last long, and the wind will shift, because it would be a shame for people to miss out on seeing the changes happening on Kilauea right now. Not to mention that living in a vog haze is pretty miserable, especially if you have respiratory problems (like me).