Mark Twain once described Lake Tahoe as “a noble sheet of blue water. It must surely be the fairest picture the whole earth affords.” The lake is blessed with beauty thanks to its iconic cobalt blue waters. How is this natural jewel in Sierra Nevada mountains so phenomenally blue? Scientists at the University of California Davis measured a “quantification of Tahoe’s blueness” based on wavelengths of light coming from the lake. Data from a NASA-operated buoy in the lake enabled researcher Shohei Watanabe to create a Blueness Index that quantified Lake Tahoe’s color for the first time.

Related article: 

• Tahoe Daily Tribune: Volunteers rally for 25th year of Lake Tahoe ecosystem restoration event