Lituya Bay

Lituya Bay

Oblique aerial photograph of Lituya Bay in the Summer of 1958. Damage from the 1958 megatsunami appears as the lighter-colored areas on the shores where trees have been stripped away.
Location North Pacific Ocean
Coordinates 58°38′13″N 137°34′23″W / 58.63694°N 137.57306°W / 58.63694; -137.57306 (Hudson Bay)Coordinates: 58°38′13″N 137°34′23″W / 58.63694°N 137.57306°W / 58.63694; -137.57306 (Hudson Bay)
River sources Lituya Glacier
Cascade Glacier
Crillion Glacier
Basin countries United States
Max. length 14.5 km (9.01 mi)
Max. width 3.2 km (1.99 mi)

Lituya Bay (/lˈtjjə/; Tlingit: Ltu.aa,[1] meaning "No Lake Within") is a fjord located on the coast of the Southeast part of the U.S. state of Alaska. It is 14.5 km (9.0 mi) long and 3.2 km (2.0 mi) wide at its widest point. The bay was noted in 1786 by Jean-François de La Pérouse, who named it Port des Français. Twenty-one of his men perished in the tidal current in the bay.

Description

The smaller Cascade and Crillon Glaciers and the larger Lituya Glacier all spill into Lituya Bay, which is a part of Glacier Bay National Park and Preserve. Cenotaph Island is located roughly in the middle of the bay. The entrance of the bay is approximately 500 m (0.31 mi) wide, with a narrow navigable channel.[2]

The bay is known for its high tides, which have a range of approximately 3 m (9.8 ft). Tidal currents in the entrance reach 9.4 km/h (5.1 kn). The entrance is considered dangerous to navigation, especially when the tidal currents are running, but the interior of the bay provides good protection to anchored ships.[2]

Lituya Bay is also famous for four recorded tsunamis, in 1854, 1899, 1936, and 1958.[3][4]

1958 megatsunami

Spruce tree shattered by the force of the water.

The same topography that leads to the heavy tidal currents also created the highest wave from a tsunami in recorded history. On July 9, 1958, an earthquake caused a landslide in the Gilbert Inlet at the head of the bay, generating a massive megatsunami measuring between 100 ft (30 m) and 300 ft (91 m). The wave possessed sufficient power to snap off all the trees up to 1,720 feet (520 m) high on the slope directly opposite the landslide. There were three fishing boats anchored near the entrance of Lituya Bay on the day the giant wave occurred. One boat sank and the two people on board were killed. The other two boats were able to ride the waves. Among the survivors were William A. Swanson and Howard G. Ulrich, who provided accounts of what they observed. Based on Swanson's description of the length of time it took the wave to reach his boat after overtopping Cenotaph Island near the bay's entrance, the wave may have been traveling 120 mph. When it reached the open sea, however, it dissipated quickly. This incident was the first direct evidence and eyewitness report of the existence of megatsunamis.[3]

See also

Wikimedia Commons has media related to Lituya Bay megatsunami.

References

  1. Teben'kov, M.D.; Translated by R.A. Pierce (1981) [1852], Atlas of the Northwest Coasts of America: From Beering Strait to Cape Corrientes and the Aleutian Islands with Several Sheets on the Northeast Coast of Asia, Kingston, Ontario: Limestone Press, p. 27, ISBN 0-919642-55-1. Spelled L'tua in translation of Tebenkov's log.
  2. 1 2 United States Coast Pilot 9. p. 130.
  3. 1 2 "Don J. Miller, Giant Waves in Lituya Bay, Alaska". Uwsp.edu. Retrieved 2013-12-03.
  4. Casey, Susan. The Wave. Doubleday, 2010, pp. 153-158

External links

Eyewitness reports of the tsunami

This article is issued from Wikipedia - version of the Thursday, April 28, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.