Input data

The climate data from 120 meteorological stations inside and closed to the study basin (Figure 2) were obtained from the China Meteorological Administration (CMA). The data set is available from 1982 to 2000 with the daily precipitation, mean temperature, maximum and minimum temperatures, mean surface relative humidity, sunshine duration, and cloud amount. The vegetation condition index leaf area index (LAI) and Fraction of Photosynthetically Active Radiation absorbed by green vegetation canopy (FPAR) was obtained from Myneni et al. (1997). The LAI and FPAR datasets are available with monthly temporal frequency from 1982 to 2000. Information about fraction of irrigation area with in each grid cell was obtained from Siebert et al. (2005). The meteorological data at the stations was interpolated to 10×10 km gridded dataset using angular distance weighted (ADW) averaging method (New et al., 2000). Figure 3 shows mean annual precipitation within 10×10 km grid cell, and also the percent irrigated area within the grid cells.

Figure 3: (a) Mean annual precipitation and (b) percent irrigated area in the Yellow River basin

4#4

The LAI and FPAR datasets were resample to the same resolution for model use. SiB2 land cover is available at USGS Global Land Cover Characterization dataset. The Food and Agriculture Organization (FAO) global soil type map (Source: Land and Water Development Division, FAO, Rome) was used to produce the grid soil properties such as soil water potential at saturation, soil hydraulic conductivity at saturation, soil wetness parameter, porosity and averaged slope. Serval empirical formulas are used to estimate the soil hydraulic and thermal parameters (Cosby et al., 1984).