Tracking Climatic Changes Using Glacial Traces and Evidence at Hezar Mountain, Iran

Abstract

Although the current situation of the Iran’s land and the dominance of arid and semiarid conditions cast a doubt on the existence of glacier reign in this land, there is evidence of geomorphological traces of glaciers in different areas of Iran indicating the function of glaciers in these regions. Therefore, regarding these traces and evidences, the past climatic conditions can be reconstructed. Based on what mentioned above, this study mainly aimed to trace the climatic changes through the glacial traces and evidences on the Hezar Mountain. Tracing the climatic changes indicates that the temperature of the study area was 6.58 °C colder than that of the current temperature during the period of glacial reign. In addition, the isopluvial map of the Hezar Mountain during the period of glacial reign indicates that the minimum rainfall at that time was 617 mm at the outlet of the basin and the maximum rainfall was 1340 mm at the highest part of the basin. On the other hand, glacier cirques, glacier valleys, and moraines were identified as the most characteristic geomorphological evidence of glaciers in the study area. Finally, laboratory indicators (granulometry), as a complement to glacier evidence, proved the existence of glacial sediments in the Tenguieh Basin. In addition, the permanent snow line was estimated at the height of 3326 meters in the Tenguieh Basin during the glacial reign and based on Porter’s cirque floor height et the height of 3333 m through the Wright method.