Hydrology & Water Resources Engineering - Vol 2 | 21. Evapotranspiration Equations: Penman and Blaney & Criddle Methods by Abraham | Learn Smarter
Students

Academic Programs

AI-powered learning for grades 8-12, aligned with major curricula

Professional

Professional Courses

Industry-relevant training in Business, Technology, and Design

Games

Interactive Games

Fun games to boost memory, math, typing, and English skills

21. Evapotranspiration Equations: Penman and Blaney & Criddle Methods

21. Evapotranspiration Equations: Penman and Blaney & Criddle Methods

Evapotranspiration is a crucial process in the hydrological cycle, combining evaporation and transpiration, significantly influencing water resource management. The Penman and Blaney & Criddle methods are key techniques for estimating evapotranspiration, with distinct applications based on data availability and climate conditions. Understanding these methods is essential for effective irrigation scheduling, water resource planning, and hydrological modeling.

17 sections

Enroll to start learning

You've not yet enrolled in this course. Please enroll for free to listen to audio lessons, classroom podcasts and take practice test.

Sections

Navigate through the learning materials and practice exercises.

  1. 21
    Evapotranspiration Equations: Penman And Blaney & Criddle Methods

    This section covers the essential concepts of evapotranspiration (ET) and...

  2. 21.1
    Concept Of Evapotranspiration

    Evapotranspiration (ET) is the combined process of evaporation and...

  3. 21.2
    Penman Method

    The Penman Method estimates potential evapotranspiration (PET) using a...

  4. 21.2.1
    Introduction To Penman Equation

    The Penman Equation estimates potential evapotranspiration (PET) using...

  5. 21.2.2
    Components Of Penman Equation

    This section details the key components of the Penman Equation used for...

  6. 21.2.2.a
    Net Radiation (Rn)

    Net Radiation (Rn) is the balance of incoming and outgoing radiation at a...

  7. 21.2.2.b
    Aerodynamic Term

    The aerodynamic term plays a crucial role in the Penman equation for...

  8. 21.2.2.c
    Temperature And Vapor Pressure Parameters

    This section discusses the computation of saturation vapor pressure and...

  9. 21.2.3
    Advantages And Limitations Of Penman Method

    The Penman Method for estimating potential evapotranspiration (PET) has...

  10. 21.3
    Blaney And Criddle Method

    The Blaney and Criddle method is an empirical approach for estimating crop...

  11. 21.3.1
    Introduction

    The Blaney and Criddle method estimates seasonal crop evapotranspiration...

  12. 21.3.2
    Blaney And Criddle Equation

    The Blaney and Criddle Equation estimates crop evapotranspiration based on...

  13. 21.3.3
    Calculation Of The P Factor

    The p factor is crucial for estimating crop evapotranspiration in the Blaney...

  14. 21.3.4
    Crop Coefficient (K)

    The crop coefficient (k) is a dimensionless value that varies based on crop...

  15. 21.3.5
    Limitations Of Blaney And Criddle Method

    The Blaney and Criddle method has significant limitations, including its...

  16. 21.4
    Comparison Of Penman And Blaney & Criddle Methods

    This section provides a comparison between the Penman and Blaney & Criddle...

  17. 21.5
    Applications In Civil Engineering

    This section discusses the key applications of evapotranspiration methods in...

What we have learnt

  • Evapotranspiration is the total loss of water from soil through evaporation and transpiration.
  • The Penman Method combines energy balance and aerodynamic principles for estimating potential evapotranspiration (PET).
  • The Blaney & Criddle Method provides a simpler empirical approach suitable for regions with limited climatic data.

Key Concepts

-- Evapotranspiration (ET)
The combined process of evaporation from soil and water surfaces and transpiration from plant surfaces.
-- Potential Evapotranspiration (PET)
The evapotranspiration that would occur if water is abundantly available.
-- Actual Evapotranspiration (AET)
The evapotranspiration that actually occurs, considering soil moisture limitations.
-- Penman Method
A physically-based approach to estimate potential evapotranspiration using energy balance and aerodynamic principles.
-- Blaney & Criddle Method
An empirical method for estimating evapotranspiration based on temperature and daylight hours, suitable for regions with limited data.

Additional Learning Materials

Supplementary resources to enhance your learning experience.