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The SGZ Layering Options form provides the user with the option of specifying the maximum and minimum layers to be used in the model, as shown in Figure 4. The Typical Rise Above Initial Conditions option may be utilized to address the bathymetric variationsvariations between initial conditions and typical water levels. While it can be utilized for all the Simga Sigma Z options, it was specifically designed for use with SGZ =2. The purpose of this function is to raise or lower the depth of the water level in the lake to a more typical value compared to the initial conditions to allow for , thereby ensuring more appropriate layer splits. For example, the initial condition of a lake may be a meter below the typical value, so the user would set the typical water rise value to 1, so that the layer splits are configured based on the typical conditionconditions. In a tidal system, it would make sense to make set this value so that it is close to the mean tide water level. The user can also lower or raise over a certain area by using a polygon.
After selecting Set SGZ Layering and OK, the layers are all automatically updated to the Sigma Stretch layering. 
Figure 4. SGZ Layering Options.
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