*3.2. Data*

Research data was from three main sources. Rainfall and temperature records were from the Spanish Meteorological State Agency (AEMET), considering all available stations. Forty-four weather stations provide Ter basin 1980–2015 rainfall records, and eleven weather stations contribute Llobregat basin records. Each zone drawn with the same color represents an area with equal rainfall estimation by the Thiessen polygon method (Figure 2).

The calibration of the HBV model discharge results uses data from stream gauging stations of the ACA managed upper basins. As it is not possible to use gauging stations data in basin lower zones, we calibrated the ACA hydrological simulated data with the historical calibrated upper zone discharge data and compared the computed values against the HBV model dataset.

**Figure 2.** (**a**) Division of sub-basins for the reservoir system on the Ter river; (**b**) Aquifers in the Ter river basin; (**c**) Division of sub-basins for the reservoir system on the Llobregat river; (**d**) Aquifers in the Llobregat river basin. The red dots indicate the placement of the meteorological stations in the Ter and Llobregat basins. The large red circles with black edge indicate gauging stations that are named as the sub-basin where they are located.

In addition to the observed data, downscaled climate-model outputs were collected from the Climate Research Foundation database [25], as shown in Table 2. These local time series are outputs from a statistical downscaling method of Ribalaygua et al. [26] based on analog stratification and transfer functions. Data include local simulations of ERA-Interim reanalysis and nine CMIP5 models under both historical experiments (1951–2005) and future projections (2006–2100) under RCP4.5 and RCP8.5.


