The Sierras near Mammoth Lakes. Photo credit: Brian Calvert  The
Sierras near Mammoth Lakes. Photo credit: Brian Calvert   Gold
made California boom. But water kept it going. That’s especially
true for Los Angeles, whose never-ending quest for water is a
deep part of its history. Much of LA’s water comes from the snow
captured each winter in the Sierra Nevada mountains, and the
water collected each spring in the state’s vast system of
reservoirs. The problem is, we’ve never really known how much is
up there. And these days it’s more confusing than ever.  But Dr.
Tom Painter, a snow researcher for NASA’s Jet Propulsion Lab,
thinks he’s found an answer. Painter’s answer to the water
problem is an airplane he calls the Airborne Snow Observatory,
and it can measure vast stretches of mountain snow—from the
air. The plane is equipped with two very cool, high-tech
instruments. One is called a LiDar, which pulses a huge laser
across the surface of the mountains, to measure the snow depth.
The other is called a spectr