10:15 AM - 10:30 AM
[ACC28-06] Snowmelt monitoring of alpine zone in Japan by using time-lapse cameras
In this study, a new method for monitoring alpine zones by digital cameras was developed in order to detect yearly change of snow-cover areas at high temporal and spatial resolutions. We used images from cameras that have been installed at mountain lodges in the northern Japanese Alps (at elevations around 2350-3100 m) and at around Mt. Rishiri in Hokkaido. RGB digital numbers were derived from each pixel within the images. The snow-cover and snow-free pixels were statistically classified by analysis of variance of gray-level histograms. In this discriminate analysis method, a flexible threshold was determined for each image to maximize the between-class variance.
The detected distributions of the snowmelt dates showed site-specific characteristics and yearly variations. Finally, we produced ortho-rectified maps of snowmelt dates over North Alps areas and Mt. Rishiri.