Tonight makes 3 sunsets in a row that I've seen multiple green flashes. They were separated by ~8 sec (an estimate). I was late & missed the beginning so I only saw 3 but each was different. The last had 3 thin slivers of intense green!

On all 3 nights, the sun sank into ...

... a thick marine layer. I think I know what's going on. The distortion of the sun's image -- looks like a stack of pancakes -- suggests there are several distinct layers, with similar vertical profiles of index of refraction: eg, rarefied above becoming denser/colder ...

... towards the ocean surface. As the top of the sun passes down thru each layer, the last bit of it peels off when it reaches the cold dense sub-layer and the critical 'mirage' refractive index. It then turns green as it shrinks b/c green bends the most. Blue & violet ...

... bend more, but they are scattered out of the beam by Rayleigh scattering, leaving green as the last. Then, when the top of the sun's image passes through the next sub-layer, it starts all over again. Amazing to witness.

I should say, I observed all this through ...

... binoculars. The details were too fine & faint to see naked eye. Anyone with a cold ocean and a daily marine layer this time of year should look for it. It's a mesmerizing spectacle.