NYT/MAMOUTH LAKES, CA-3/2/2017– The Sierra Snowpack is much deeper than it has been in many many years. NASA has a plane that research scientists from the Jet Propulsion Lab use to record telemetry about the snowpack. We fly over the eastern Sierras in the Mammouth Lakes area where NASA has collected data. . .. . . . . . . . . . . . . . .. . . . . . . . .. . . .. . . . . . .. . . . . <<<<>>>>: Trees on a slope in the snow covered eastern Sierras. CREDIT PHOTO–JIM WILSON/THE NEW YORK TIMES. 10203627A NYTCREDIT: Jim Wilson/The New York Times