Conclusions
The glacier research is significant due to the fact that the glaciers occupy approximately 11% (16 million square kilometres) of the earth’s land area. The glaciers contain a large number of fresh-water (30 million km3), which is the 2/3 of the earth’s fresh water supply. Georgia possesses more than 600 glaciers and their detailed study is important from several points of view. In present research satellite remote sensing research is done for the main glaciers located on the territory of East Georgia.
The scientific study of glaciers in the Caucasus was started during the first half of 18th century. In the last century the terrestrial observations on glaciers were carried out. Due to the difficulties of organization and conducting the field works the terrestrial observations data resulted in different series of various temporal duration characteristics of glaciers. The data received contain an uncertainties. From another hand carrying out of field works are expensive and data gathered have no sufficient spatial and temporal resolution.
With launch of the Earth’s satellites it was determined that satellite remote sensing is the best technology allowing to receive data with needed regularity in terms of both time and space resolution. Some uncertainties remain in the data as the observational tool is too far away from the Earth’s surface. So, the necessity for the strong quality assessment/quality control (QA/QC) remains. A lot of studies showed that the best method for investigation of glaciers is application of satellite remote sensing combined with terrestrial observations and expert knowledge of separate glaciers.
In cases whenever the terrestrial observations are not available and expert knowledge is absent, validation is not possible. In our research maximum length, area, minimum elevation are not determined for some glaciers, namely: SU4G08011056, SU4G08011057, SU4G08011058 and SU4G08011059. Accordingly only some information about those glaciers is presented but the detailed conclusions about them is not possible to make at that stage.
Based on the detailed comparison of the output data received using the satellite remote sensing provided with the QA/QC with the similar data from the glaciers catalogue it can be concluded that during the last 50 years all the characteristics of the main glaciers from the East Georgia are changing as follows:
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The minimum elevation and equilibrium line altitude are increasing;
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The length and area as well as the ablation area are decreasing.
The carried researches define that impact of modern climate change is well expressed in East Georgian glaciers retreat due to modern warming.
It would be noted that the complex research of the glaciers using different sources’ data such as satellite remote sensing, terrestrial observations and expert knowledge is effective for better accurate determination of glaciers’ main characteristics.