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Owens Lake, California
Note: This caption refers to the image versions labeled "NASA's Earth Observatory web site".
This astronaut photograph highlights the mostly dry bed of Owens Lake, located in the Owens River Valley between the Inyo Mountains and the Sierra Nevada. Shallow groundwater, springs, and seeps support minor wetlands and a central brine pool. Two bright red areas along the margins of the brine pool indicate the presence of halophilic, or salt-loving organisms known as archaeans. Grey and white materials within the lake bed are exposed lakebed sediments and salt crusts. The towns of Olancha and Lone Pine are indicated by the presence of green vegetation indicating a more constant availability of water.
The present-day Owens Lake was part of a much larger lake and river system that existed during the Pleistocene Epoch (~ 3 million to ~12,000 years ago) along the current northeastern border of California with Nevada. Meltwater from alpine glaciers in the Sierra Nevada filled the regional valleys of the Basin and Range to form several glacial lakes that were ancestral to the now-dry lakebeds (or playas) of Owens, Searles Lake, and China Lake.
While Searles and China Lakes dried out due to regional changes to a hotter and drier climate over thousands of years, Owens Lake became desiccated largely due to the diversion of Owens River water in the early 20th century to serve the needs of the City of Los Angeles, CA located 266 kilometers to the south. Following complete desiccation of the lakebed in 1926, significant amounts of windblown dust were produced - indeed, the term "Keeler fog" was coined by residents of the now largely abandoned town on the eastern side of Owens Lake due to the dust.
In addition to adverse health effects on local residents, dust from Owens Lake has been linked to visibility reduction in nearby national parks, forests, and wilderness areas. Recently, efforts to control dust evolution from the lakebed have been undertaken by the City of Los Angeles.
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