CLOSE-RANGE PHOTOGRAMMETRY AS A TOOL IN GLACIER CHANGE DETECTION

• Main Authors: T. Pitkänena, K. Kajuuttib
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: KEY WORDS; Photogrammetry; close range; terrestrial; change detection; glaciology; Engabreen; Norway; Svartisen; glacier
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.642.9842; http://www.isprs.org/proceedings/XXXV/congress/comm7/papers/151.pdf

The shape and texture of ice surface can give us valuable information about processes affecting glaciers. This presentation introduces a procedure for making close-up digital elevation models (DEM) of glacier surface and the benefits of using these DEMs in glaciological change detection. They can be used to follow accurately the changes of different surface features like melt water channels, glacier tables, ablation hollows etc. The DEMs have been produced using digital photogrammetric methods. To keep the amount of ground control points reasonable concentric images have been connected to panoramic wide-angle images. Experimental research has been carried out using two study sites situated on Engabreen in the West Svartisen in Norway and on Hintereisferner in Austria. Test areas have been small, only 10 x 10 m. Tacheometer and GPS have been used for ground control measurements. The photography has been recorded once a year during a period of three years. DEMs have been constructed using commercial photogrammetric workstation and are very detailed with 20 –50 cm point density. Results indicate that close-up DEMs can be used to densify more sparse DEMs and to detect chances in ice structure and movements.