Definitions for "Ground truthing"
measurements conducted on the ground or at sea to calibrate, compare or verify observations made from satellites or aircraft
Verification of the accuracy of data by actual field investigation of areas that have been remotely sensed.
the use of a ground survey to confirm the findings of an aerial survey or to calibrate quantitative aerial observations.
verifying maps by checking the actual occurrence of plant and animal species in the field at representative sample locations
On-site inspection of features located on a map.