Glossary of Terms - E

EC mapping

The use of information on the characteristics of a soil revealed by measuring its electrical conductivity to create a soil map.

EGNOS (European Geostationary Navigation Overlay Service)

A satellite-based augmentation system developed by the European Space Agency. EGNOS is the European equivalent to WAAS in the US.

Electromagnetic spectrum

All wavelengths of electromagnetic energy, including visible light, x-rays, ultraviolet rays, infrared light, microwaves, and radio waves.


A method or technique to extend data or inferences from a known location to another location for which the values are not known.