15.7.1.2. Conversion of point rainfall to areal rainfall

Try these first

1. 1.

   What is point rainfall?

   Hint

   Think about where rain is measured.

2. 2.

   Name one method used to convert point rainfall to areal rainfall.

   Hint

   What is the simplest method?

3. 3.

   What is the main purpose of converting point rainfall to areal rainfall?

   • To improve accuracy
   • To have a higher gauge count
   • For aesthetic reasons

   Hint

   Why do we need better data representation?

4. 4.

   True or False: The Arithmetic Mean Method is the most accurate for uneven rainfall areas.

   • True
   • False

   Hint

   Consider the limitations of the method.

5. 5.

   Given rainfall data from four gauges: 7 mm, 12 mm, 10 mm, and 20 mm. Using the Arithmetic Mean, calculate the areal rainfall. Then discuss how this method might not reflect true areal rainfall in an area with varying distributions.

   Hint

   Consider if there are any gauges much higher or lower than others.

6. 6.

   You have rainfall data from five locations forming a Thiessen polygon. The gauges show 5 mm, 10 mm, 15 mm, 20 mm, and 25 mm. Discuss how you would apply these data using the Thiessen Polygon Method.

   Hint

   Think about how you would determine which gauge influences which area.