Answer Happy

(a) Provide three reasons why the polygon Thiessen method is more superior to any other method in computing the aerial rainfall of a watershed. (b) The double mass curve of rainfall consistency is based on the basic principle of statistic that says, "When each recorded data comes from the same parent population, they are consistent". Explain further on this statement based on your understanding of this subject matter. (c) A new reservoir is to be constructed at the downstream of a watershed, as shown in Figure Q2. For planning purposes, mean areal rainfall of the watershed is required. As a water resource engineer in charge of the project, you are required to determine the mean areal rainfall of the watershed using simple averaging and polygon method. The annual average rainfall for Station A, B, C, D, E, and F are 1200, 1100, 1500, 1300, 1400, and 900 mm, respectively. Every square in the diagram represents the area of one square kilometre.
Figure 2: Map of the watershed