John Metcalfe was CityLab’s Bay Area bureau chief, covering climate change and the science of cities.
The new color scheme is neon-eggplant.
The Calbuco eruptions aren't just creating a spectacle in southern Chile, with their lightning-streaked mushroom clouds and reverse-terraforming of the land into an ashen, "gray desert." Thousands of miles away they're showboating in Brazil, too, turning sunsets a weird, neon shade of eggplant.
The volcano erupted last Wednesday after more than four decades of silence. Now the sulfurous aerosols it coughed into the atmosphere are making it to the rest of South America. You can see them smudged all over the continent and ocean in this NASA image from Sunday:
When lofted up high, volcanic particles can mess with the sky's normal palette. Tony Phillips of the stellar site Spaceweather explains more:
Purple is one of the telltale signs of a volcanic sunset. Fine volcanic aerosols in the stratosphere scatter blue light which, when mixed with ordinary sunset red, produces a violet hue. But purple isn't the only thing to look for, says atmospheric optics expert Les Cowley. In addition, he advises, sky watchers in Chile and Brazil should "be alert for a very bright yellow twilight arch, fine cloud structure in the arch seen through binoculars, and long diffuse rays and shadows."
Sure enough, Rio de Janeiro's skyline this weekend was backdropped by a color reminiscent of Nicki Minaj's lipstick. These photos were shot by Spaceweather reader Helio C. Vital, who reports the lavender radiance persisted an hour after sundown: