USGIF Exam| 195 Questions and Answers (Verified Answers)

What are the advantages of remote sensing? - - covers large areas - repetitively looks at the same area - sees things that the human eye can't - sees many parts of the EM spectrum simultaneously - provides geo-references What are some non-military applications of remote sensing? - - land use mapping - forest and agriculture applications - telecommunication planning - environmental applications - hydrology coastal mapping - urban planning - emergencies and hazards Definition of remote sensing - the art, science, and technology of obtaining reliable through the process of recording, measuring, and interpreting imagery and digital representation of energy patterns derived from non-contact sensor systems Photogrammetry - the art, science, and technology of obtaining reliable information about physical objects and the environment, information about physical objects and the environment through processes of recording, measuring and interpreting photographic images and patterns of recorded radiant electromagnetic energy and other phenomena What are passive sensors/what do they do? - They collect reflected or emitted energy: - do not send out any energy or radiation - measure properties of energy reflected or emitted from objects - collection dependent on energy source and ability to measure/characterize energy returned (sun was the energy source for Corona - no collection at night or through clouds)What are active sensors/what did they do? - They collect reflected energy too: - send out radiation (microwave pulse or laser beam) - measure the strength, spectral properties, and other aspects of the "return" or "echo"