Lake Lahontan
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- For the modern reservoir, see Lake Lahontan (reservoir)
Ancient Lake Lahontan was an enormous endorheic lake that existed during the ice age, covering much of northwestern Nevada, extending into northeastern California and southern Oregon. At its peak approximately 12,700 years ago (during a period known as the "Sehoo Highstand"), the lake had a surface area of about 8,000 square miles (20,700 km²), with its largest component centered at the location of the present Carson Sink. The depth of the lake was approximately 800 feet (240 m) at present day Pyramid Lake, and 500 feet (150 m) at the Black Rock Desert.
Climate change around the end of the Pleistocene epoch led to a gradual desiccation of ancient Lake Lahontan. The lake had largely disappeared in its extended form by approximately 9,000 years ago. As the surface elevation dropped, the lake broke up into series of smaller lakes, most of which rapidly dried up leaving only a playa. These playas include the Black Rock Desert, the Carson Sink and the Humboldt Sink. The only modern day remnants existing as true lakes are Pyramid Lake and Walker Lake. Winnemucca Lake has been dry since the 1930s and Honey Lake periodically desicates and has been dry since mid 2003. The ancient shoreline is evidenced by tufa formations throughout the area.
Surprisingly, the watershed feeding Lake Lahontan is not thought to have been significantly wetter during its highstand then it is currently. Rather, its desiccation is though to be mostly due to increase in the evaporation rate as the climate warmed. Recent computer simulations indicate that if precipitation and evaporation rates within the watershed were maintained at their historical yearly maximum and minimum, respectively, Lake Lahontan would return.
The existence of the lake coincided roughly with the first appearance of humans in that region of North America. Archaelogical evidence exists along the ancient lake shore of early human habitation.
See also
External links
- Exploring Nevada's Ice Age Lake (http://www.rangerovers.net/expeditions/lakelahontan/)