i04 CIMIS Reference Evapotranspiration Zones v1999

The ETo Zones Map allows users to view the grass-reference evapotranspiration (ETo) Zones for the State of California. The map was developed by DWR and UC Davis in 1999 and divides the State into 18 zones based on long-term monthly average ETo. The ETo values were calculated using data from various data sources, including CIMIS weather stations that had at least five years of archived data. This dataset is the version from 1999.