Thermal-infrared remote sensing of stream temperatures at multiple spatial scales

摘要: Stream temperature is an important indicator of water quality, particularly where endangered fish populations are sensitive to elevated water temperature. Regional assessment of stream temperatures from the ground is limited by sparse sampling in both space and time. Remotely sensed thermal-infrared (TIR) images can makes spatially distributed measurements of the radiant skin temperature of streams. We quantify and discuss the accuracy and uncertainty limits to recovering stream temperatures in the Pacific Northwest for a range of stream widths (10–500 m), and TIR pixel sizes (5–1000 m) from remotely sensed airborne and satellite TIR images. Among locations with more than three pixels across the stream, the difference between the image and in-stream temperature measurements averaged 1.15 oC with a standard error (SE) of 0.16 oC, while the corresponding uncertainty (spatially weighted standard …