22.4.1. Empirical Methods

Try these first

1. 1.

   What does PET stand for?

   Hint

   Think about what evaporates from the earth.

2. 2.

   Name one empirical method for estimating PET?

   Hint

   They are based on temperature and day length.

3. 3.

   What does the Thornthwaite Method primarily rely on for estimating PET?

   • Rainfall data
   • Temperature and day length
   • Soil moisture

   Hint

   Remember the factors it specifically uses.

4. 4.

   True or False: The Blaney-Criddle Method is less flexible than the Thornthwaite Method.

   • True
   • False

   Hint

   Think about which method can apply widely.

5. 5.

   Given an average day length of 15 hours, a mean monthly temperature of 30°C, and an empirical coefficient of 0.8, calculate the PET using the Thornthwaite Method.

   Hint

   Don't forget to adjust each variable into the equation.

6. 6.

   Compare the results of the Thornthwaite and Blaney-Criddle methods when estimating PET under the same climatic conditions in a tropical versus a temperate region. Discuss the differences in approach and reliability.

   Hint

   Think about how each method uses different variables in climates.