Mono Basin: Precipitation
Rainfall in the Mono Basin varies considerably with elevation.
Vorster (1985, 57) notes that high elevation stations record mean annual
precipitation of 20-40 inches. Low elevation stations (such as the station
on the east shore of Mono Lake) record as little as 4 inches/yr.
Vorster also reports that estimates of average annual precipitation for
the basin can vary from around 7 to 11 inches/year from one study to another.
Vorster's (1985, 63) estimate is 8 inches/yr based on the 1937-1983 time
period. His estimate matches the estimate by the Los Angeles Department
of Water and Power.
Vorster's model calculates the precipitation flow as the product of the
precipitation rate and the surface area of the lake. If the lake covered
39 thousand acres, for example, the preciptation flow would be around 26
KAF/yr:
29 KAF/yr = 39 Kacres * 0.67 ft/yr
Note: You might be concerned that the precipitation flow is based on the
surface of the lake rather than the area for the basin as a whole. If so,
be sure to take note of Vorster's treatment of "net land land surface
precipitation," one of the other in flows to
the basin.