Ice circles are a natural anomaly known to rarely occur in very cold climates. Scientists speculate that they are formed from whirlpools that rise to the surface and then freeze in the shape of a perfect circle. The largest reported ice circle was measured at 150 meters in diameter.
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Icebergs in the Antarctic area sometimes have stripes, formed by layers of snow that react to different conditions. Blue stripes are often created when a crevice in the ice sheet fills up with meltwater and freezes so quickly that no bubbles form. When an iceberg falls into the sea, a layer of salty seawater can freeze to the underside. If this is rich in algae, it can form a green stripe. Brown, black and yellow lines are caused by sediment, picked up when the ice sheet grinds downhill towar...
Eruption lightning at Krakatau - Volcanic eruption with lightning forming inside the ash cloud