Evolution of temperature in granule and intergranular space

The temporal evolution of temperature in a dissolving granule and in an adjacent intergranular space is presented. The semi-empirical evolutionary models have been calculated using an inversion method applied to 4-min time series of Stokes I spectral line profiles. The models are presented in the form of the functional dependence of temperature T(log tau_5,t) on optical depth tau_5 at 500 nm and time t. The observed disappearance of the granule is accompanied with overall cooling of the granular photosphere. Temperature changes greater than 100 K have been found in deeper (log tau_5 => 0) and upper layers (log tau_5 <=-2) whereas the intermediate layers are thermally stable. The intergranular space, which is 2 arcsec off the granule, keeps the temperature structure of the layers from log tau_5=0.5 to log tau_5=-2 without global evolutionary changes except short-term and spatially confined heating. Finally, the significant temperature changes in the upper layers (log tau_5 <= -2.5) observed during the time interval of 4 min are found to be typical for the granular and intergranular photosphere.