Grewingk Glacier is a 13-mile-long (21 km) glacier located in the Kenai Mountains, near Kachemak Bay, in the U.S. state of Alaska.
 
Because glacial mass is affected by long-term climatic changes, glaciers are considered among the most sensitive indicators of climate change and are a major source of variations in sea level.
 
A large piece of compressed ice, or a glacier, appears blue as large quantities of water appear blue. This is because water molecules absorb other colors more efficiently than blue. The other reason for the blue color of glaciers is the lack of air bubbles. Air bubbles, which give a white color to ice, are squeezed out by pressure increasing the density of the created ice.