20 images Created 15 Nov 2014
Glaciation
Glaciers are amazing phenomena that illuminate the higher and lower latitudes of the earth, and are undoubtedly one of the natural wonders of Alaska. There are an estimated 100,000 glaciers in Alaska. Glaciers are rivers of ice that flow from ice fields high in the mountains, and are constantly fed by the accumulation and compression of the annual snowfall. In constant motion, they can move several feet a day or even surge as much as 300 feet (90 m). Some are retreating due to increased melting, possibly because of climate change, or less snowfall feeding them.
Southeast Alaska has many tidewater glaciers that flow to the sea, where large slabs of ice break off, or calves at the head of fjords or inlets, which become clogged with the icebergs. The creaking of calving glaciers, followed by the crashing of the ice into the water and subsequent waves, is one of the greatest spectacles that you can regularly experience in Alaska. The beautiful blue colour of glacial ice is created by the density according to its age, which absorbs all the colours of the spectrum except blue, which is reflected.
Approaching a tidewater glacier in either a boat or a kayak always required the greatest concentration because of the density of icebergs, and once in close proximity to the towering wall of ice there was always a great sense of awe combined with the unnerving precariousness at the prospect of a huge slab of ice being suddenly dumped into the tranquil frigid water transforming it into an undulating ice-studded leviathon.
The main glaciers that I sometimes visited in Southeast Alaska were in Glacier Bay in the north where there are 16 active tidewater glaciers, Tracy Arm and Endicott Arm, and the southernmost tidewater glacier in the USA, the Le Conte Glacier, just to the south of Petersburg. The fjords where glaciers calve are always spectacular with steep sides and many waterfalls, and the water is a distinctive glacial blue due to the sediment or glacial flour discharged by the glacier.
Southeast Alaska has many tidewater glaciers that flow to the sea, where large slabs of ice break off, or calves at the head of fjords or inlets, which become clogged with the icebergs. The creaking of calving glaciers, followed by the crashing of the ice into the water and subsequent waves, is one of the greatest spectacles that you can regularly experience in Alaska. The beautiful blue colour of glacial ice is created by the density according to its age, which absorbs all the colours of the spectrum except blue, which is reflected.
Approaching a tidewater glacier in either a boat or a kayak always required the greatest concentration because of the density of icebergs, and once in close proximity to the towering wall of ice there was always a great sense of awe combined with the unnerving precariousness at the prospect of a huge slab of ice being suddenly dumped into the tranquil frigid water transforming it into an undulating ice-studded leviathon.
The main glaciers that I sometimes visited in Southeast Alaska were in Glacier Bay in the north where there are 16 active tidewater glaciers, Tracy Arm and Endicott Arm, and the southernmost tidewater glacier in the USA, the Le Conte Glacier, just to the south of Petersburg. The fjords where glaciers calve are always spectacular with steep sides and many waterfalls, and the water is a distinctive glacial blue due to the sediment or glacial flour discharged by the glacier.
