When the surface of the sea freezes—such as around the north and south poles—it does so in a way that forces pockets of especially cold and salty seawater to gather on the underside of the ice. This mixture of brine is denser than the seawater below it, and as a result it tends to slowly sink to the bottom. Now, because it’s so cold, the fresher water below the brine actually freezes around it as it falls, which results in a giant icicle under the surface.
To put it simply, frost flowers are flowers made of frost. More accurately, frost flowers are nothing like that, so let’s put it technically instead: they’re buildups of ice particles around the base of certain plants and types of wood.
Mammatus clouds are pouch-like protrusions hanging from the undersides of clouds, usually thunderstorm anvil clouds but other types of clouds as well. Composed primarily of ice, these cloud pouches can extend hundreds of miles in any direction, remaining visible in your sky for perhaps 10 or 15 minutes at a time.
If someone asked you to name the two coolest things you could ever see in nature, your answer would be “volcanoes and lightning.” Or possibly “lightning and volcanoes,” I guess, but those are the only two options—it’s just a fact. But nature, it seems, is constantly looking for new ways to impress us—which is why it went ahead and made volcanic lightning a reality.And yes, it’s exactly what it sounds like—a lightning storm that takes place in the middle of a volcanic eruption. Scientists aren’t 100% sure why this happens, but the primary theory goes that when a volcano erupts, it projects positively-charged debris into the atmosphere. These charges then react with negative charges already present, which results in 1) a bolt of lightning, and 2) a really cool picture.