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We have carried out calculations, showing how the thermodynamical structure ef the sunspot umbra atmosphere varies during two stages of the oscillatory process of "umbral flashes".

We have calculated profiles of five Call lines using three models of the solar atmosphere with different mean temperature gradients in the chromosphere. Contribution functions and response functions to temperature and velocity variations for the line centers and for the K 2 and H 2 emission peaks were found. Disturbances were specified locally at each point of the chromosphere, but for temperature disturbances the other thermodynamical parameter distributions were redetermined. Effective heights of the contribution and response functions, and also the width of the layer reacting to disturbances, depend substantially on the line strength and on the temperature gradient. Contribution curves and response functions to velocity variations differ drastically in form but, in spite of this, their centers of gravity and widths have a similar behaviour. The response function to temperature variations differs from the former two in all its characteristics.

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