Dolra River basin is located in the southern slope of the Central Caucasus, in the territory of Zemo Svaneti and joins the Enguri River basin, which in its turn is the main center of the contemporary glaciation in Georgia. The article presents the changes in the number and area of the Dolra River basin glaciers during the last century in connection with the climate elements. Along with the dynamics of glaciers, the course of the air temperature and atmospheric precipitation has been identified in the 20th century and in the beginning of the 21st century. In the mentioned study, except of the old topographic maps and aerial images, we used the climate information that we have collected from Mestia weather stations (Mestia is the regional center of Zemo Svaneti, where the only operating weather station is located at present).

The data of 2014 have been obtained by the Landsat aerial images of L8 OLI/TIRS (Operational Land Imager and Thermal Infrared Sensor) taken in August 2014. Gobejishvili-the Georgian glaciologist of the 20th-21st centuries, composed on the basis of 1:50,000 scale topographic maps of 1960.

In order to identify the area and number of the glaciers of the 60s of the 20th century, we used the work of R. Also, we used the catalog of the glaciers of the southern slope of the Caucasus compiled on the basis of the 19th century maps in 1911 by a well-known researcher of the Caucasus K. During the study, we used the 1:42,000 scale topographic maps of the 19th century, which were drawn up during the first topographic survey by using the plane-table surveying method. Dolra River basin is located in the south- ern slope of the Central Caucasus, in the territory of Zemo Svaneti and joins the Enguri River basin, which in its turn is the main center of the contemporary glaciation in Georgia. This new glacier inventory can be used as a basis dataset for future studies including glacier change assessment. Analysis of possible controls suggest that the general decreases in both glacier area and number for the period 1960-2014 are directly due to general increase in temperature, especially in summer (June-July-August), although the response of individual glaciers was modulated by other factors, including glacier size, elevation, rock structure, exposition, morphological type and debris cover. This represents a 28.8☒.2% (481☑0.6 km2) reduction in total glacier surface area between 19 and a marked acceleration in the rate of area loss since 1986. Glacier margins were mapped manually and reveal that, in 1960, the mountains contained 2349 glaciers, with a total glacier surface area of 1674.9☓5.2 km2. Large scale topographic maps and satellite imagery (Landsat 5, Landsat 8 and ASTER) were used to conduct a remote sensing survey of glacier change in the Greater Caucasus mountains. Here, we present an expanded glacier inventory for this region over the 1960-1986-2014 period. While there are a large number of glaciers in the Greater Caucasus, the region is not fully represented in modern glacier databases with previous incomplete inventories. We found, that topography thresholds related to the elevation and hypsometry of individual catchments controlled the gradient of the rate of glacier expansion in the domain at that time. The longest glaciers were located in the Enguri (Nenskra ~36 km, Mulkhura ~35.1 km, Dolra ~34.5 km), Kodori (Sakeni ~25 km, Klichi ~20 km, Marukhi ~17.3 km) Rioni (Buba ~23 km, Kirtisho ~20.5 km, Jejora ~17.5 km) and Tergi (Devdoraki ~38.5 km, Suatisi ~32 km) river basins. The current investigation has revealed that in the Late Pleistocene, the central and western Caucasus characterized the highest glaciation, while the eastern Caucasus boasted the lowest glaciated area, and in the southern Georgia's highland glaciation has almost the same form as there is in the Eastern Caucasus today. In addition, the rates of glaciation of those times are identified based on the stadial moraines and erratic boulders. We used the analog method with the 30 m resolution SRTM DEM (Shuttle Radar Topography Mission Digital Elevation Model). Our primary aim was to numerically reproduce the ice extent deduced from geological and geomorphological mapping. This article presents the information of the Georgian Caucasus glaciation at the Late Pleistocene and Holocene period (~126,000-11,700 calendar years ago).

Glims production russia