Source:

Moratto, Michael J., Thomas F. King and Wallace B. Woolfenden
1978   Archaeology and California's Climate. Journal of California Anthropology 5:147-161.

Dates in the original article are expressed as "B.P." These are interpreted here as radiocarbon ages, and they have been converted to calendar years using Calib 6.0 and informally estimating midpoints within the one-sigma intercept ranges.