On the Hawaiian Islands, a state of the United States, there is a small island called Kauai, located 120 km from Honolulu. It is beautiful like a green gem set upon the blue sea. The beaches on the island feature a sand dune that rises 18 meters above sea level, composed entirely of pristine white sand. When walking on the white sand, it emits a sound resembling a dog barking. Running on the sand amplifies the sound, making it resonate like thunder. Why does this happen? Some speculate that there is water beneath the sand dune, and between the sand and the water is a resonant cavity formed by steam and air. The sound reflects and refracts multiple times, creating resonance that amplifies the sound into a booming echo.
(Photo: kauai-beachfront)
Not far from the sand dune, there is a black rock formation created by lava. The lava has been eroded by the ocean, forming many small caves, one of which resembles a geyser, shooting out white foam. Each eruption produces a sound similar to a trumpet, akin to the sound whales make when they spout water. After several small eruptions, there is a larger one, with the water foam reaching heights of up to 20 meters, creating a stunning spectacle.
Kauai Island boasts breathtaking scenery. Riding along the stream, one can witness the tranquil rural landscapes. After rain, rainbows frequently appear in the sky, sometimes showcasing 5-6 rainbows at once, with some overlapping. The northeastern corner of Mount Waialeale receives the largest average annual rainfall in the world, reaching 11,684 mm. Even more intriguing is that the southwestern slope of Waialeale receives only 460 mm of rain.
(Photo: honeymoonislands)
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