The impact of Big Island vog on the state of Hawaii

It was a quiet weekend for me with regard to this blog as we were in Kona for a  swimming meet. More on that later, in the meantime…

In his post, A Very Voggy Day, Andrew provides a nice link to the MODIS satellite which took  visual images of the island. The clouds are the really white, fluffy stuff. The murky, grey looking stuff is the vog which is generated by Kilauea and which the trade winds carry off to the rest of the island chain.

The image dramatically demonstrates how, when the trade winds are blowing, the best place to be is the east coast of the Big Island of Hawaii.

Halema`uma`u’s plume heads for Hilo

On the way down from the summit after finishing for the night we noticed something spectacular.

It wasn’t a great night – it was cloudy throughout which closed off the other optical and infrared telescopes, but because the JCMT is a submillimetre (i.e. sensitive to microwave radiation) telescope we can see through the clouds. However, the stability and ‘wetness’ of the atmosphere above us was poor, so although we could work it wasn’t great.

It was cloudy above but it was clear down to the coast and we had a great view of the volcano. In these pictures you can see the plume of volcanic emissions coming from the Halema`uma`u vent from the top of Kilauea volcano. Tom had some nice pictures of it close up when he went on his ‘shopping trip’ this weekend. The pictures below aren’t as clear as I would like (click on them to get a better look) as the Sun hadn’t fully risen yet so getting the right exposure (bright sky & dark ground) was tricky as I wanted to try and preserve some of the colour in the sky – I’ll see if I can improve them a bit when I get them into Lightroom on my return home.

I never cease to be humbled by the place we are privileged to call our workplace. It always gets me as we drive down from the summit, the fact that we are (usually) looking down onto the cloud tops rather than up. In these images we are looking down onto another volcano as its exhaust plume is carried away by the wind.

Ah, but notice, where is that plume heading? Not out to the ocean as usual. That’s because the trade winds that usually come in from the east and carry the vog (a uniquely Hawai’ian term, I believe, for ‘volcanic fog’) out to the ocean and beyond (and affecting the sky lines and respiratory systems of folks on our neighbour islands) are not there. Not this day. The winds were coming from the west (we call them ‘Kona winds’) and carrying the vog straight to Hilo!

I spoke with Mila that afternoon and she said that the vog was particularly bad that day…. no wonder.