A term currently in circulation among marine biologist
s, environmental hazard
assessors, and others who rely on satellite
data to find things out about our planet
. Many of the satellites they use have been in orbit--either geostationary
or whipping around the globe
every ninety minutes--for decade
s, and the info they send back is steady and reliable, but the incurable curiosity of scientist
s requires that it be verified.
Thus, these guys and gals see a pattern that's remarkable and dispatch a human being or a team of them to test soil/water samples at the exact point of interest at the exact time the satellite in question is beaming back info. This practice is called "ground truthing." (They use it as a verb.)
As one molecular biologist I know put it, "You've got the satellite up there scanning the ocean, you've got a NASA plane with a facsimile of the same sensor scanning the ocean, and you've got a guy with a cigarette hanging out of his mouth dipping a bucket into the ocean at the same time. Isn't the technology supposed to take care of this?"
Well, it is. But to ground truth the technology is, I think, a sound practice. Relying solely on what satellites tell us is bad science, I would say. Use them to find patterns worth exploring, but for Newton's sake, send a person to observe them before you draw conclusions that are supposed to be meaningful to people.