Open AccessPerspectives on water flow and the interpretation of FLIR images
Author(s) -
S. L. Larson,
L. L. Larson,
P. A. Larson
Publication year - 2002
Publication title -
journal of range management
Language(s) - English
Resource type - Journals
eISSN - 2162-2728
pISSN - 0022-409X
DOI - 10.2458/azu_jrm_v55i2_larson
Subject(s) - streams , channel (broadcasting) , infrared , watershed , hydrology (agriculture) , remote sensing , environmental science , interpretation (philosophy) , flow (mathematics) , water flow , surface water , geology , meteorology , geography , optics , soil science , mechanics , physics , engineering , computer science , environmental engineering , geotechnical engineering , telecommunications , computer network , machine learning , programming language
Airborne infrared thermal radiography has been proposed as a tool which may be used to monitor the water temperature along the network of streams and rivers which compose a watershed. The proponents of this method correlate vegetative shadows on a stream channel with reduced infrared radiation (IR) reception in the radiographic data to suggest that the water temperature is reduced in such areas. Two methods are employed to demonstrate that this interpretation of the data is in error. First, the fundamental principles of thermodynamics are employed to show that if the stream is in fact flowing, the water affected by any cooling process cannot remain in the vicinity where it was cooled. Second, temperature data taken from a stream channel are used to show that the water flowing in the channel is essentially unaffected by the patterns of vegetative shade on the surface of the channel.