A two-dimensional solar model

A two-dimensional, nearly flux constant solar atmosphere which includes a physical model of granulation is presented. If the inhomogeneous character of the solar photosphere is neglected in the construction of empirical models, the result is an underestimate of the temperature gradient in the layers below a Rosseland optical depth of 0.5 and an overestimate of the convective flux penetration into the observable layers. The two-dimensional model adequately reproduces the mean limb darkening, the magnitude and center-to-limb variation of the intensity fluctuations, and the rms vertical and horizontal convective velocities.