Abstract:
A watershed management program is usually based on the results of watershed modeling. Accurate modeling results are decided by the appropriate parameters and input data. Precipitation is the most important input for watershed modeling. Precipitation characteristics usually exhibit significant spatial variation, even within small watersheds. Therefore, properly describing the spatial variation of precipitation is essential for predicting the water movement in a watershed. This study is concerned with mapping annual precipitation in Jam and Riz watershed of Iran, from sparse point data using Inverse Distance Weighting (IDW) method. The objective in the optimization process is to minimize the estimated error of precipitation. Thus the performance of each interpolation was assessed through examination of mapped estimates of elevation. The results show that the estimated error is usually reduced by this method. Particularly, when optimized exponent in IDW method was selected for digital elevation model which, is secondary variable for the annual average precipitation gradient equation. It was conclude that IDW3 with the best conditions and lowest mean standard error provides the most accurate estimates of precipitation.
Machine summary:
Evaluating optimized digital elevation precipitation model using IDW method (Case study: Jam Riz Watershed of Assaloyeh, Iran) S.
This study is concerned with mapping annual precipitation in Jam and Riz watershed of Iran, from sparse point data using Inverse Distance Weighting (IDW) method.
Particularly, when optimized exponent in IDW method was selected for digital elevation model which, is secondary variable for the annual average precipitation gradient equation.
In particular, they have been employed to build continuous representations of terrain, soil composition, terrestrial, atmospheric pollution and climate variables (Heuvelink and Webster, 2001; Hutchinson and Gallant, 1999; Javris and Stuart, 2001a, b; Kurtzman and Kadmon, 1999; Mitas and Mitasova, 1988; Oliver and Webster, 1990; Philip and Watson, 1982).
Geographical location of Jam Riz watershed in Iran Determining the optimized digital elevation model using interpolation method of IDW First, they have scanned as topographic maps and then georeferenced in Erdas Imagin9.
Standard ellipse and standard deviation ellipse for elevation point group During the past three decades, models that solve the catchments and or solute transport equations in conjunction with n optimization technique have been increasingly used as watershed management tools (Rizzo and Dougherty, 1996; Minsker and Shoemaker, 1998; Zheng and Wang, 2002; Mayer et al.
Optimized digital elevation model (IDW3) Identifying the average gradient of annual precipitation using available data base technique was used (Mahdavi, 2007):1 px p px (14)In first stage the total available stations in px n p * A p * pB ...