Antarctic

$Blue icebergs develop from older, deep glaciers which have undergone tremendous pressure experienced for hundreds of years. The process releases and eliminates air that was originally caught in the ice by falling snow. Therefore, icebergs that have been formed from older glaciers have little internal air or reflective surfaces. When long wavelength light from the sun hits the iceberg, it is absorbed, rather than reflected. The light transmitted or refracted through the ice returns as blue or blue-green. Older glaciers also reflect incident light preferentially at the short wavelength end of the spectrum due to Rayleigh scattering, much in the same way that makes the sky blue.$

$A blue iceberg is visible after the ice from above the water melts, causing the smooth portion of ice from below the water to overturn. The rare blue ice is formed from the compression of pure snow, which then develops into glacial ice. Icebergs may also appear blue due to light refraction and age.$

[Show slideshow]