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Professional Evapotranspiration Calculator for Agricultural Applications
Welcome to the official documentation for EVAPOTRAN, a professional evapotranspiration calculator for agricultural applications developed by Flaha Agri Tech.
EVAPOTRAN is a comprehensive calculator designed for professionals in horticulture, agronomy, landscaping, and agricultural engineering. This web application provides essential tools for precise calculations of evapotranspiration using the FAO Penman-Monteith method, supporting irrigation management and water resource planning.
- Manual Calculator: Enter climate data directly to calculate reference evapotranspiration
- EPW Import: Upload EnergyPlus Weather files to extract climate data
- Weather Visualization: Generate heatmaps and visualize weather patterns
- Live Weather: Connect to real-time weather data for immediate calculations
New to EVAPOTRAN? Start here:
- Introduction - Learn what EVAPOTRAN is and why it's useful
- Installation - Set up EVAPOTRAN on your system
- Quick Start Guide - Make your first calculations
This documentation is available in multiple formats:
- Web: Browse online at https://evapotran-doc.flaha.org
- GitHub Wiki: View on GitHub Wiki
- PDF: Download complete documentation as PDF
- GitHub: View source files in our GitHub repository
Need help? Check these resources:
EVAPOTRAN is licensed under the GNU General Public License v3.0. See the License page for details.
EVAPOTRAN implements the FAO Penman-Monteith equation for calculating reference evapotranspiration (ET₀):
Where:
-
$ET_0$ = reference evapotranspiration [mm day⁻¹] -
$R_n$ = net radiation at the crop surface [MJ m⁻² day⁻¹] -
$G$ = soil heat flux density [MJ m⁻² day⁻¹] -
$T$ = mean daily air temperature at 2 m height [°C] -
$u_2$ = wind speed at 2 m height [m s⁻¹] -
$e_s$ = saturation vapor pressure [kPa] -
$e_a$ = actual vapor pressure [kPa] -
$\Delta$ = slope of vapor pressure curve [kPa °C⁻¹] -
$\gamma$ = psychrometric constant [kPa °C⁻¹]
This internationally recognized method provides a standardized approach to estimating evapotranspiration, enabling accurate water management decisions across different climates and regions.