Glacial Waters

The icy blue color seen in runoff from glaciers, like Fitzsimmons Creek in Whistler, is due to a phenomenon known as glacial flour. As a glacier moves, it grinds the underlying rock into a fine powder called "rock flour." When this powder mixes with meltwater, it creates a suspension that diffuses sunlight. The suspended particles in the water preferentially scatter light in the short-wavelength spectrum, including blue and green light. However, because water absorbs more green light, we typically see the scattered light as a vivid blue. This combination of rock flour and light scattering results in the stunning, mesmerizing blue of glacier-fed bodies of water.Read more