Defining Project Requirements

The Philippines case study’s objective was to assess the impact of climate change on irrigation design water duty, which is a parameter required for designing capacities of irrigation channels. The assessment was conducted for a location (Cabanatuan City, 15°42’N; 120°54’E) in the province of Nueva Ecija.

The assessment considered the periods 1971–2000 and 2036–2065 as the baseline and future time periods, respectively. These periods were chosen to be consistent with the previous report from the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) as well as climate simulation availability.

The study required daily rainfall data at a location. Through scoping and step 4, it was known there was a number of GCM data (from the CMIP5 website) and downscaled climate data of around 25 km resolution over the site. Observed data was required to bias correct the climate model data.