Question

The Penman’s evapotranspiration equation is based on

• A. Water budget method
• B. Energy balance approach only
• C. Mass transfer approach only
• D. Energy balance and mass transfer approach

Hint:

Penman’s equation combines both energy balance and mass transfer to model evapotranspiration.

Answer 1

The Correct Option is D

Step 1: Understanding Penman’s Equation.
Penman’s evapotranspiration equation incorporates both energy balance and mass transfer approaches. It uses energy balance to calculate the energy available for evaporation and the mass transfer approach to calculate the transfer of water vapor from the surface.
Step 2: Conclusion.
Thus, Penman’s equation is based on both energy balance and mass transfer approaches, making option (4) the correct answer.

Final Answer: \[ \boxed{4. \, \text{Energy balance and mass transfer approach}} \]