ice flowers
© VK / Timofey Shutov
Spring is normally the season for buds to bloom but before Christmas thousands of extremely rare ice 'flowers' exploded onto the landscape of a Russian national park. Sadly, no sooner had they blossomed, and they were gone.

The thousands of crystalline blossoms bloomed on Valdai Lake in northwestern Russia on Tuesday and, thankfully, visitors had their cameras on hand to capture the rare sight in all its majesty.

The phenomenon was caused by a sudden temperature drop, the director of the Valdai National Park, Nikolai Sokolov, explained.

For context, this is how Valdai Lake usually looks during winter.

Valdai lake winter
© Wikimedia
"Just yesterday, in Valdai we had a small minus, and today thermometers showed about -20," Sokolov said. He added that, in all his 24 years in Valdai, this was the first time he had witnessed such an astonishing, and beautiful, sight.

Conditions need to be perfect for such a rare phenomenon to take place: while the lake's waters are still warm enough to flow, a sudden cold snap creates ice near the surface.

ice flowers close up
© VK / Timofey Shutov
Water lapping over the top of the ice cools sharply and freezes to form the crystalline petals, and the process repeats, in some cases forming 'flowers' that are several centimetres high.

The phenomenon was short-lived, however, as increased wind, a rise in temperatures and heavy snowfall conspired to quickly obliterate the frost-bitten blossoms from the landscape almost as quickly as they had appeared.