نوع مقاله : علمی - پژوهشی
نویسندگان
1 استادیار گروه عمران دانشکدة مهندسی، دانشگاه بوعلی سینا، همدان
2 استاد گروه فتوگرامتری و سنجش از دور، دانشگاه صنعتی خواجه نصیرالدین طوسی
3 دانشیار گروه فتوگرامتری و سنجش از دور، دانشگاه صنعتی خواجه نصیرالدین طوسی
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Mountain Glaciers are pertinent indicators of climate change and their surface velocity changes, are an essential climate variable. In order to retrieve the climatic signature from surface velocity, large scale study of glacier changes is required. Satellite remote sensing is an effective way to derive mountain glacier surface velocities. In this research, we have conducted a comprehensive assessment of Alam-Chal glacier surface changes (include displacement and velocity), all based on remotely-sensed data. All datasets include aerial photos and satellite images were ortho rectified, normalized and co-registered. By using an aerial photograph collected in 1955 as a baseline and comparing it against a 2003 image collected by the SPOT satellite, the glacier retreat, in direct response to changes in local climate conditions were extracted. Furthermore, we have assessed short-term changes over two-time scales (1988-2003, 2003-2005),using an aerial photo acquired in 1988, a 2003 SPOT image, and a high-resolution Quick Bird image collected over the study area in 2005. We have derived accurate glacier surface velocity vectors (RMSE~2m), based on an FFT-based image cross-correlation technique. Our results point to the capability of the proposed method in accurately retrieving glacier surface changes at a high level of spatial detail, which is important for studies of regional climate change.
کلیدواژهها [English]