Degree of Master of

GIS methods

GIS methods have been applied for the calculation of the AALS water surface area and volume during 1969-2009 as one of the important parts of the present research. For the calculation of the AALS water surface area in various time periods the following GIS methods of data analysis have been applied:

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  Comparative method based on the analysis of the land use datasets;
  
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  Comparative method based on the analysis of the USSR military maps;
  
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  Use of Digital Elevation Maps (DEM);
  
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  Remote sensing provided by the MultiSpec program.
  

3.3.3.1 Arcview program

CEU eTD Collection
The Arcview program has been chosen for the practical exercise, i.e. calculation of the AALS water-surface area and volume during 1969-2009. The main reason of using this program is a presence of a certain amount extensions which enable to calculate water-surface area easily. Another reason is convenient and understandable toolbar in the Arcview program which makes working process very effective.
The Arcview program has been used for the first three methods listed above. In the first method, comparative method based on the analysis of the land use datasets, use of the Arcview has been basically related to the working with land use datasets during all exercise’s steps. Application of the Arcview program in the second method, comparative method based on the analysis of the USSR military maps, was necessary only for the final step of the exercise, namely, for the calculation of the AALS water-surface area. Use of the Arcview in
the third method was appropriate for the creation of the AALS Digital Elevation Maps succeeded by calculation of the water-surface area.

4. Remote sensing

As mentioned above, remote sensing is one of the GIS methods applied for the AALS calculation of the water-surface area during 1969-2009. Characterized by two major peculiarities, it has been decided to present the method concerned separately from another methods used. In general, the main features are:

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  it is more sophisticated and time-consuming method in comparison with first three methods;
  
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  it allows research to occur on time scales, both in duration and frequency, that were previously impossible;
  
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  it often allows the investigation of portions of the Earth that are difficult or dangerous to reach;
  
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  specific softwares are required for this method; MultiSpec program has been selected for the present research (Sabins 1994).
  

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