Gw. Kite et al., SIMULATION OF STREAMFLOW IN A MACROSCALE WATERSHED USING GENERAL-CIRCULATION MODEL DATA, Water resources research, 30(5), 1994, pp. 1547-1559
General circulation models (GCMs) currently perform vertical water and
energy balances at 20- or 30-min time intervals for grid points 2-deg
rees-4-degrees apart but generally contain no information on the land-
phase transfer of water between grid points or within watersheds. As a
result, they operate on an incomplete hydrological cycle. This study
combines a hydrological model with a GCM for a macroscale watershed. A
water balance was carried out at 12-hour time intervals for a 10-year
period using the Canadian Climate Centre GCM II data set for grid poi
nts within and surrounding the 1.6 X 10(6) km2 Mackenzie River Basin i
n northwestern Canada. The water surpluses from each relevant grid poi
nt were accumulated to provide a simulated hydrograph at the outlet of
the Mackenzie River. A hydrological model was calibrated and verified
using 5 years of recorded climatological and hydrometric data as well
as land cover data from classified National Oceanic and Atmospheric A
dministration advanced very high resolution radiometer images. The cli
matological outputs from the GCM (precipitation, temperature, and evap
oration) were then used as inputs to the hydrological model, generatin
g a second hydrograph for the Mackenzie River. The results show that u
sing the hydrological model with the GCM data produces a better repres
entation of the recorded flow regime. The study provides a means of ve
rifying the performance of the GCM and is a first step in developing a
continental-scale hydrological model which will, ultimately, form a p
art of a full model of the global hydrological cycle.