Perception visual range and sky background |
| |
| Authors: | AW Harrison LB Murdock |
| |
| Institution: | Department of Physics , University of Calgary , Calgary, Alberta |
| |
| Abstract: | Abstract The meteorological visual range Vm and the perception visual range Vp have been measured for a variety of horizon sky backgrounds and atmospheric extinction conditions. Comparison with the standard visibility Vn shows that in general Vp > Vm > Vn . Model calculations of Vp, Vm and Vn for different synthetic sky backgrounds and for an extinction coefficient function of the form σ(λ) = k λ‐α in which a was varied from ‐1 to 4 show that the wavelength of maximum perception can vary between ～540 and ～630 nm. Under typically turbid or polluted atmospheric conditions and for a blue or white sky background the extinction coefficient should be measured at ‐570 nm if prevailing visibility is to be reliably estimated. |
| |
| Keywords: | |
|
|
