Skip to content
  • Home
  • About
    • Privacy Policy
  • Categories
    • Hiking & Activities
    • Outdoor Gear
    • Regional Specifics
    • Natural Environments
    • Weather & Forecasts
    • Geology & Landform
Geoscience.blogYour Compass for Earth's Wonders & Outdoor Adventures
  • Home
  • About
    • Privacy Policy
  • Categories
    • Hiking & Activities
    • Outdoor Gear
    • Regional Specifics
    • Natural Environments
    • Weather & Forecasts
    • Geology & Landform
Posted on September 27, 2022

Derive Reference Potential Evapotranspiration from Potential Evapotranspiration

Earth Science

Asked by: Kim Hill

How is reference evapotranspiration calculated?

where ETo = reference evapotranspiration rate (mm d-1), T = mean air temperature (°C), and u2 = wind speed (m s-1) at 2 m above the ground. Equation 3 can be applied using hourly data if the constant value “900” is divided by 24 for the hours in a day and the Rn and G terms are expressed as MJ m-2 h-1.

What is the difference between reference evapotranspiration and potential evapotranspiration?

Reference evapotranspiration is that from a grass surface that is well-watered. Potential evapotranspiration is that from a surface that has unlimited water (such as a lake).

How do you calculate potential evapotranspiration from actual evapotranspiration?

it is simple… ETc=Kc. ET0; where ETc is actual evapotranspiration, Kc is crop coefficient and ET0 is Referece evapotranspiration. You might get Kc values based on the specified crop as well as its stage of growth.

What are the three methods to determine potential evapotranspiration?

Methods for evaluating evapotranspiration can be divided into three categories: hydrologic or water balance methods, analytical methods based on climate variables, and empirical estimates. The water balance method to determine Ev consists of catchment hydrology, soil water depletion sampling, and lysimetry testing.

What is reference evaporation?

The reference evaporation, a concept introduced in the 1990’s by the Food and Agriculture Organization (FAO) and presented in this paper, defines the evaporation potential of standard vegetation with an abundant water supply.

What is reference and crop evapotranspiration?

Reference crop evapotranspiration or reference evapotranspiration, denoted as ETo or ETref, is the estimation of the evapotranspiration from the “reference surface.” The reference surface is a hypothetical grass reference crop with an assumed crop height of 0.12 m, a fixed surface resistance of 70 s/m and an albedo of

What is the difference between AET and PET?

PET is a function of relative humidity, solar radiation, water availability, wind, and temperature. AET or ET is how much water is going to evaporate when there is a water limitation. AET is a function of vegetation cover, root, and soil. Usually, PET is larger than ET.

What is the difference between ET and PET?

Potential evapotranspiration (PET) is defined as the maximum amount of water that can be removed from a land surface through evapotranspiration (ET) as sum of both evaporation and transpiration given abundant supply of soil moisture. In other words, the removal of water by ET depends only upon the available energy.

What is potential evapotranspiration in hydrology?

Potential evapotranspiration (Ep) is the water vapor flux under ideal conditions of complete ground cover by plants, uniform plant height and leaf coverage, and an adequate water supply; From: Trace Fossils, 2007.

Why the value of AET is less than pet?

If the water supply to the plant is adequate, soil moisture will be at field capacity then, the ratio of AET to PET = 1. If the water supply to the plant is inadequate, then the ratio of AET to PET is less than 1. In clayey soils, AET/PET is almost equal to 1.

What is the Penman Monteith equation used for?

The Penman–Monteith equation is widely used in land process modeling to estimate vegetation transpiration or soil evaporation because it requires only conventional observations as input and does not require input from two levels.

What is the meaning of actual evapotranspiration?

Actual Evapotranspiration (ETa) is the quantity of water that is removed from a surface due to the processes of evaporation and transpiration and is measured in millimeters (mm). ETa is scene-based and derived from the Landsat Level-2 Surface Temperature products.

What is ETo and ETc?

The estimated crop water requirement (ETc) for high growth rates is obtained by multiplying the specific crop coefficient (Kc) by reference evapotranspiration (ETo). ie. ETc = ETo x Kc.

What is the importance of reference evapotranspiration?

Actual evapotranspiration is a key factor of hydrological cycle and agricultural water management. Therefore, in a sense, the accurate forecast for reference evapotranspiration plays an important role in understanding the hydrological cycle, especially in planning and managing irrigation practices.

What are the units of ETo?

0.7 || 0.6 || ETo units can be in ‘English’ (inches) or Metric (millimeters). Many factors can affect the rate of evaporation from an open body of water; depth of water, area of the water, temperature of water, topography and vegetation surrounding the body of water, etc.

How is evaporation rate calculated?

The equation states that, the evaporation rate, W = (95+0.425*V)*(Pw-Pa)/Y, where W is the Evaporation rate in lb/h-ft2; V is the air velocity at water surface; ft/min; Pw is the saturation vapor pressure at water temperature, in. Hg; Pa is saturation vapor pressure at air dew point, in.

How is Penman Monteith equation calculated?

Δ = (0.00815 Ta + 0.8912)7 = 1.447 mb/°C. The vapor pressure deficit is (Ponce, 2014: Section 2.2): (es – ea) ≅ (eo – ea) = eo [ 1 – (φ / 100) ] = 23.37 [ 1 – (70 / 100)] = 7.01 mb.

What is the normal evapotranspiration rate?

Estimates of the mean annual evapotranspiration have been derived from hydrologic budgets for each State. These estimates indicate that statewide evapotranspiration within the conterminous United States ranges from about 10 inches per year in the semiarid Southwest to about 35 inches per year in the humid Southeast.

What is a lysimeter and how does it work?

A lysimeter (from Greek λύσις (loosening) and the suffix -meter) is a measuring device which can be used to measure the amount of actual evapotranspiration which is released by plants (usually crops or trees).

How is lysimeter measured?

A lysimeter is a measuring device which can be used to measure the actual evapotranspiration which is released by plants. By recording the amount of precipitation that an area receives and the amount lost through the soil, the amount of water lost to evapotranspiration can be calculated.

What is lysimeter experiment?

Lysimeter experiments were conducted to determine the ability of different soils to reduce levels of biochemical oxygen demand (BOD) and concentrations of molybdate reactive phosphorus (MRP) and ammonium-N (NH4(+)-N) in dirty water and the impact of applications on nitrate leaching.

New Posts

  • Headlamp Battery Life: Pro Guide to Extending Your Rechargeable Lumens
  • Post-Trip Protocol: Your Guide to Drying Camping Gear & Preventing Mold
  • Backcountry Repair Kit: Your Essential Guide to On-Trail Gear Fixes
  • Dehydrated Food Storage: Pro Guide for Long-Term Adventure Meals
  • Hiking Water Filter Care: Pro Guide to Cleaning & Maintenance
  • Protecting Your Treasures: Safely Transporting Delicate Geological Samples
  • How to Clean Binoculars Professionally: A Scratch-Free Guide
  • Adventure Gear Organization: Tame Your Closet for Fast Access
  • No More Rust: Pro Guide to Protecting Your Outdoor Metal Tools
  • How to Fix a Leaky Tent: Your Guide to Re-Waterproofing & Tent Repair
  • Long-Term Map & Document Storage: The Ideal Way to Preserve Physical Treasures
  • How to Deep Clean Water Bottles & Prevent Mold in Hydration Bladders
  • Night Hiking Safety: Your Headlamp Checklist Before You Go
  • How Deep Are Mountain Roots? Unveiling Earth’s Hidden Foundations

Categories

  • Climate & Climate Zones
  • Data & Analysis
  • Earth Science
  • Energy & Resources
  • General Knowledge & Education
  • Geology & Landform
  • Hiking & Activities
  • Historical Aspects
  • Human Impact
  • Modeling & Prediction
  • Natural Environments
  • Outdoor Gear
  • Polar & Ice Regions
  • Regional Specifics
  • Safety & Hazards
  • Software & Programming
  • Space & Navigation
  • Storage
  • Water Bodies
  • Weather & Forecasts
  • Wildlife & Biology

Categories

  • Climate & Climate Zones
  • Data & Analysis
  • Earth Science
  • Energy & Resources
  • General Knowledge & Education
  • Geology & Landform
  • Hiking & Activities
  • Historical Aspects
  • Human Impact
  • Modeling & Prediction
  • Natural Environments
  • Outdoor Gear
  • Polar & Ice Regions
  • Regional Specifics
  • Safety & Hazards
  • Software & Programming
  • Space & Navigation
  • Storage
  • Water Bodies
  • Weather & Forecasts
  • Wildlife & Biology
  • English
  • Deutsch
  • Français
  • Home
  • About
  • Privacy Policy

Copyright (с) geoscience.blog 2025

We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept”, you consent to the use of ALL the cookies.
Do not sell my personal information.
Cookie SettingsAccept
Manage consent

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
CookieDurationDescription
cookielawinfo-checkbox-analytics11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional11 monthsThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy11 monthsThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
Functional
Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
Performance
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Analytics
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
Advertisement
Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
Others
Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.
SAVE & ACCEPT