10.4.3. Inverse Distance Weighting Method (IDW)

Try these first

1. 1.

   What is the main purpose of the Inverse Distance Weighting Method?

   Hint

   Think about why geographic distance matters.

2. 2.

   Explain why IDW uses distance squared in its formula?

   Hint

   What happens to weight when distance increases?

3. 3.

   What is the primary benefit of using IDW?

   • A. It is the simplest method
   • B. It uses distance to weight proximity
   • C. It does not require any data

   Hint

   Remember how distance affects the influence of station data.

4. 4.

   IDW may not function well in regions with significant what?

   • True
   • False

   Hint

   Think of areas with hills, valleys, or varied elevations.

5. 5.

   You have rainfall data from three stations; A (30mm, 1km), B (60mm, 5km), and C (80mm, 3km). Estimate rainfall at a new station using IDW. Explain your calculations.

   Hint

   What does the IDW formula tell you about weighting?

6. 6.

   Consider a scenario where you have a missing rainfall reading at a station surrounded by six others. After applying IDW, you notice the estimate is significantly lower than expected. Discuss the possible reasons.

   Hint

   What external factors could distort data readings?