Hello, everyone. I don't quite understand some physical mechanisms when I am doing research on snow depth of lidar. I hope I can get help.
When I read the previous literature, I learned that the longer the wavelength of electromagnetic wave, the stronger the ability to "bypass" snow and the higher the penetration depth. But why is 532 more penetrating than 1064nm in lidar?(artile:Lidar measurement of snow depth: a review."doi:10.3189/2013JoG12J154)
532 nm is green light and 1064 nm is infrared. Snow is very reflective at those wavelengths and penetration on ice is very small. You can usually ignore this penetration. With lidar, snow depth is measured comparing data from two different epochs, one snow-on and the other snow-off. This is well explained in the paper you mention.
In the visible wavelengths (e.g. 532 nm lidar), absorption is much lower, resulting in higher snow reflectance but greater penetration of the incident laser light into the snowpack. In the shortwave infrared (e.g. 1550 nm lidar), absorption by ice is much stronger and the snow reflectance is
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