*3.2. Modeling Approach*

A composite modeling approach was employed to reconstruct time series of annually varying Central Valley runoff, Delta outflow and salinity spanning more than 1000 years. The modeling approach, as summarized below, consists of three components. The purpose of the first component is to reconstruct a runoff time series from measured tree-ring data. The purpose of the second and third components is to reconstruct time series of Delta outflow and salinity from the modeled runoff time series representing the pre-development and contemporary periods, respectively. The three model components draw from a variety of measured and synthetic (i.e., simulated) calibration data. The model components and time periods are summarized in Table 2.


**Table 2.** Summary of modeled time periods and key variables.
