Retracing the 1910 Carruthers Royal Geographical Society Expedition to the Turgen Mountains of Mongolia – Reconstruction of a Century of Glacial Change

The Turgen Mountains lie in northwestern Mongolia, roughly 80 kilometers south of the Russian border. The area was visited in 1910 by a Royal Geographical Society (RGS) expedition led by Douglas Carruthers. They undertook an extensive survey of the range and produced a detailed topographic map. They also documented the extent of the glaciers with photographs. This modern study consisted of three phases. The first step was to procure the historical documents from the RGS in London, including copies of the photos, journal entries, and the map. Field work in Mongolia entailed traveling to the remote study site and retracing portions the 1910 expedition. Camera locations were matched to the historical photographs and repeat images taken. In addition, the termini of the two main glacial lobes were surveyed by GPS. Finally, spatial analysis was conducted in the computer laboratory using a GIS to generate a „historic‟ elevation model from the 1910 map and compare it to a modern DEM generated from SRTM data. Map analysis software was employed to evaluate cartometric accuracy of the 1910 map against modern Russian topographic sheets. The results of the DEM and map analysis were then validated using the field GPS data and remotely sensed imagery to quantitatively describe the changes in the glacial system. The repeat photography was analyzed using photogrammetric techniques to measure glacier changes. Also, a custom cartographic product was produced in the style of the 1910 Carruthers map. It displays the extent of the glaciers in 2010 and the locations of repeat photography stations for future expeditions. Placing the results of this study alongside previous work paints a clear picture of the Turgen glacial regime over the last century. The results suggest that while the snow and ice volume on the summits appears to be intact, lower elevation glaciers show significant ablation. This study successively demonstrates the utility of using historic expedition documents to extend the modern record of glacial change