[en] Measurements of oscillations in umbrae and penumbrae using the line pairs (Ca II lambda8498--lambda8542) and (Fe I lambda5434--Ca II lambda8498)= are presented for seven sunspots and 11 observing runs. In the umbral chromosphere, the observations reported here, taken with other measurements of umbral oscillations, suggest that the oscillations are upward propagating acoustic (or slow mode) disturbances, and that they become nonlinear and develop into shock waves in the upper layers. They cause a significant increase in the radiative output of the umbral chromosphere, indicating the possibility of nonthermal heating at these levels. On the basis of this picture, umbral chromosphere, indicating the possibility of nonthermal heating at these levels. On the basis of this picture, umbral chromospheres have a greater physical extent in height than predicted by umbral models with coronal pressures greater than those found in the quiet Sun. Oscillations are present in the outer regions of penumbrae with frequencies and phase relationships that suggest the possibility of magneto-gravity waves

[en] A reanalysis of Mount Wilson solar velocity observations was made to search for giant cellular patterns. The reanalysis avoids several errors made in a previous search. No cells are detected with sensitivity of 3 to 12 m s^-1 depending upon wavenumber. The observed amplitudes do not conflict with recent model predictions

[en] The average size of turbulent vortices (the correlation length) in the solar atmosphere decrease with height from 670 (h = 160 km) to 440 km (h = 250 km), while their root-mean-square velocity is constant and equal to 1.7 km x sec^-1

[en] The effect of vertical oscillations with periods between 90 s and 300 s on a solar atmosphere governed by heat conduction and radiation loss is examined. The effect is found to be primarily a redistribution, rather than a net addition or subtraction, of energy within the low corona, mainly by long period (180 to 300 s) oscillations. The redistribution of energy is found to affect the time-averaged temperature and density profiles of such an atmosphere, particularly in the low corona. The amount of energy redistributed is found to increase with increasing period. (orig.)

[en] A study of solar absorption line profiles obtained at high spatial and spectral resolution is made. The velocity fields are determined by the inversion of individual line profiles

[en] Observations of transient disturbances in the solar atmosphere are reviewed with emphasis on coronal mass ejection events

[en] The nonlocal character of the radiation field significantly modifies the radiative damping of perturbations in the solar photosphere. Gravity waves are not usually considered to exist in the solar photosphere because the radiative damping time, when based on the Newtonian approximation, is too short. However, this restriction does not apply to low order gravity waves. In fact, with the inclusion of nonlocal effects, the radiative damping for low order gravity waves becomes negative for some region in the photosphere and thus acts as a driving mechanism for gravity waves there. (orig.)

No abstract available

[en] A review of the high-energy phenomena on the solar surface is presented. The observed characteristics of flares are described and the build-up of energy prior to the flare and the mechanism of primary energy release are fully discussed. The problem of particle acceleration is mentioned. (C.F.)

[en] We present the results of an analysis of the variation of the granular velocity fluctuations with height in the photosphere. The vertical and horizontal granular velocity fluctuations are found. We argue that within these convective overshoot layers the ordered convective motion is converted gradually into another type of motion thereby inducing the velocity field of the higher photospheric layers