One additional

simulation for a 15-year period (2060–2075

One additional

simulation for a 15-year period (2060–2075) was included and the results were used to investigate hydrological consequences compared to the baseline scenario. Projected CO2 concentration and temperature is provided in Table B1. The changes in agricultural land areas were modeled in IMAGE, version 2.2 (IMAGE Team, 2001), because the model is capable of forecasting land use change based on the joint modeling of human activities and environmental processes (Dobrovolski et al., 2011). IMAGE mapped agricultural land areas on a grid of 0.5° × 0.5° spatial resolution; therefore, the output cannot be directly used as future agricultural land requirements. To downscale these projections, we weighted the actual IMAGE projections using a scenario change factor (Sleeter et BYL719 datasheet al., 2012) computed from IMAGE agricultural PARP inhibitor cancer area projection and the agricultural area estimate provided by a USGS global land cover dataset (Loveland et al., 2000). GCMs are considered to be the most appropriate means for projecting climate change. However, due to their coarse spatial resolution, it is essential to use downscaled GCM outputs rather than raw output for impact studies (Chu et al., 2010 and Wilby et al., 1999), because local scale forcings, processes, and feedbacks are not well represented in GCM experiments (Hewitson and

Crane, 2006 and Wetterhall et al., 2009). We used statistically downscaled precipitation for both A1B and A2 scenarios on the basis of empirical statistical relationships established in the SDSM (Wilby et al., 2002) between historical (1988–2004) large-scale circulation patterns and atmospheric moisture variables from the NCEP reanalysis dataset (Kalnay et al., 1996) and locally observed precipitation from the GSOD dataset for the same time period (Pervez and Henebry, 2014).

The 21st century daily precipitation was then modeled through a stochastic weather generator applying the established relationships with the probability of the precipitation depending on CGCM3.1 predictor variables. The comparison of observed precipitation with CGCM3.1 projected raw and downscaled precipitation concluded that downscaled precipitation provided consistency and attenuated uncertainties while simulating future ID-8 precipitation (Pervez and Henebry, 2014). The precipitation was downscaled at the subbasin level and daily time-series were created and assigned to each subbasins’ centroid to be used in the calibrated SWAT model. Fig. 2 illustrates the daily observed and simulated streamflow at Bahadurabad station. The shaded gray regions indicate 95% prediction uncertainty (95PPU) by the simulation. The P-factor was 0.78, which signifies that 78% of the observed daily streamflow could be bracketed by the uncertainties. The R-factor (average thickness of 95PPU divided by standard deviation) was 0.64. Although an R-factor of 0 is desirable, a value close to 1 is considered reasonable ( Abbaspour et al., 2009 and Schuol et al.

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