Dem Creation of a Snow Covered Surface Using Digital Aerial Photography

Seasonal snow plays a vital role in the world’s water resources. In some areas, seasonal snow melt provides water for agriculture, industry, hydro-electricity generation and urban water supply. Accurate estimate of the snow depth and its characteristics allows determination of the water content of the snow pack. This determination is very important in water management regimes. This paper presents a component of a research project undertaken in Falls Creek Ski Resort in Victoria, Australia. Snow depth has traditionally been measured using point samples, with an ad hoc distribution across the resort, mainly in areas of interest and extrapolated to give a value of snow depth for an area. Previous efforts to use photogrammetry to create DEMs (Digital Elevation Model) of snow (or glaciers) have used a large ground sample distance (GSD) or small scale photography, and have yielded 1-2 metre accuracies, in the Z component. This has limited use in Australia, where snow depths rarely exceed 3 metres. This paper investigates using high resolution digital aerial photography to create a DEM of a snow covered surface of a small area.