Potential Evapotranspiration (ETo)
Potential Evapotranspiration is the amount of water that could be evaporated and transpired if the water supply was unlimited. The principal weather parameters affecting evapotranspiration are radiation, air temperature, humidity, and wind speed.
Crop Evapotranspiration (ETc)
The crop evapotranspiration under standard conditions, denoted as ΕΤc is the evapotranspiration from disease-free, well-fertilized crops, grown in large fields, under optimum soil water conditions, and achieving full production under the given climatic conditions. It is a critical parameter for irrigation management and helps farmers to determine how much water their crops need to grow and produce optimal yields.
Normalized Difference Vegetation Index (NDVI)
NDVI (Normalized Difference Vegetation Index) is a remote sensing index that measures plant "greenness" and health by analyzing the difference in reflectance between near-infrared and visible light wavelengths.