Dynamical Behavior of the Upper Solar Photosphere

Abstract. The dynamical behavior of upper cool-star photospheres constitutes the next step in realistic atmosphere modeling after the suc-cessful numerical implementation of low-photosphere granulation. The solar example shows that this behavior is complex even when magnetism is ignored. Acoustic waves are a principal ingredient, but so are at-mospheric gravity waves. Acoustic events provide less pistoning than expected. Correlation and Fourier analyses of image sequences from TRACE demonstrate the ubiquity of gravity waves