Although part of the photograph is obscured by the Shuttle window (blackness along upper left), the Sierra Nevadas are discernible. The green, irrigated San Joaquin Valley and its reservoirs contrast markedly with the arid conditions of the sparsely vegetated east side of the Sierra Nevada Range. The western slopes are more gradual than the precipitous eastern slopes and are characterized by a series of east-west trending, deeply eroded streams and canyons that transport large quantities of snowmelt. To the east, the Owens River Valley separates the Sierra Nevadas from the White Mountains, whose crest exceeds 14 000 feet (4265 meters). The White Mountains area is so cold, dry, and high that it qualifies as a cold desert. Apparent east of the Sierra Nevadas are Mono Lake and Walker Lake.