a wishful shade of mauve
Aug. 28th, 2019 09:17 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
corviThe Ulawun Volcano in Papua New Guinea erupted August 3rd, flinging ash and sulfur oxides eighteen kilometers up, all the way into the stratosphere, which is unusual. Patchy clouds of stratospheric volcanic ejecta have recently reached North America.
Volcanic ash scatters light and makes the sky blue, which isn't normally visible, the sky already being blue and all, but the blue ashglow can mix with normal reddish sunset light to make intense purple sunsets. The pattern if a patch of ash happens to be in exactly the right place is a purple sky above a yellow arch at the horizon, the yellow banded with faint darker horizontal lines (the ash itself), sometimes with blueish-purple rays radiating out from the yellow arch.
There can also be large faint blue halos around the sun during the day.
juli and I have been keeping an eye out for a purple sunrise, or a blue halo, and we got a teeny bit of purple this morning, or at least that's what I'm telling myself. Hello tiny adventurous ash cloud! I hope you enjoyed
your wander over to our island. Yay volcano sky.
(PS A volcano sky that requires less wishful thinking, fromdorchadas 's vacation photos: third photo down.)
Volcanic ash scatters light and makes the sky blue, which isn't normally visible, the sky already being blue and all, but the blue ashglow can mix with normal reddish sunset light to make intense purple sunsets. The pattern if a patch of ash happens to be in exactly the right place is a purple sky above a yellow arch at the horizon, the yellow banded with faint darker horizontal lines (the ash itself), sometimes with blueish-purple rays radiating out from the yellow arch.
There can also be large faint blue halos around the sun during the day.
juli and I have been keeping an eye out for a purple sunrise, or a blue halo, and we got a teeny bit of purple this morning, or at least that's what I'm telling myself. Hello tiny adventurous ash cloud! I hope you enjoyedyour wander over to our island. Yay volcano sky.
(PS A volcano sky that requires less wishful thinking, from
dorchadas 's vacation photos: third photo down.)
no subject
Date: 2019-08-28 09:45 pm (UTC)Thanks! No immediate air quality issues for us; the ash is kilometers above the ground here. Though Ulawun single-handedly (single... rockedly?) creates about 2% of the world's sulfur dioxide air pollution, and has for decades, so arguably there are air quality issues for everyone on the planet.
(Across the Pacific, thousands of people were evacuated from the towns close to the volcano, but as far as I've read, everyone got out and there were no deaths or injuries. Hooray! Good job, humans.)