Estimation of the permafrost area in the Altai Mountains (Russia) in the framework of the preservation of the Frozen Tombs of the Altai Mountains

摘要

This paper is presenting a methodology for the mapping of the occurrence and evolution of permafrost on the basis of remotely sensed data, in the framework of the Frozen Tombs of the Altai Mountains project, directed by UNESCO. The tombs under focus belong to the Scytho-Siberian civilization, dating from about 800 to 300 BCE. Many of these graves or kurgans are very well preserved because they are constructed in permafrost soil. This makes them one of the most important sources of information for the study of the ancient history of Central Asia. It is believed that part of these graves, situated on lower altitudes, are located in former permafrost zones that recently disappeared. Scientific research shows that the limit of permafrost zones is slowly retreating, due to global warming. In this research we use ASTER and Landsat ETM+ scenes to study this problem. The ASTER data were used for creating a DEM showing the overall relief in the study area, using Ground Control Points (GCP's) measured during the field campaign in 2003. The analysis of the thermal band of Landsat gives an impression of temperature conditions in the study area. The image is dating from the summer period and gives therefore an idea of the "maximum of warming up" in the area. It should be noticed that this is only a test and is for sure statistically not relevant. A comparison of the temperature distribution with the DEM, more specific the altitude and the slope map, is made.