EAGER: Estimating Glacier Volume Change from Satellite Imagery

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1153140/FountainThis award supports an investigation into the feasibility of using high-resolution satellite stereo imagery in combination with historic topographic maps to estimate volume change of alpine glaciers around the perimeter of the Antarctic Ice Sheet. The contribution of glacier mass loss in Antarctica (exclusive of the ice sheet) is not well known. However, modeling suggests that it accounts for the 39% gap between observed and estimated sea level rise from the world-wide melting of glaciers and ice caps. The combination of recent advances in satellite resolution (sub-meter) and newly available photogrammetric software that can construct digital elevation models without ground control points potentially provides a cost-effective approach for evaluating glacier volume change in remote regions. The fundamental idea is to subtract the current topography (digital elevation model) based on satellite imagery from the topography based on historic maps thus providing changes in elevation and consequently glacier volume. Uncertainty is derived from on the apparent elevation differences of bedrock exposures. If successful, this application will be a powerful tool to quantitatively estimate ice mass loss in remote regions around Antarctica and significantly increase the accuracy of estimated glacier contributions to sea level rise. Several challenges are posed by this approach that justifies the EAGER program: 1) typically cloudy weather in many areas along the Antarctic coast that precludes imagery acquisition; 2) construction of DEMs of sufficient accuracy to detect change; and 3) availability of accurate historic topographic maps.