Reply to Comments by E. N. Parker

Abstract

There are three important points on which a recent paper by E. N. Parker implies disagreement with a previous paper by this author where none actually exists: (1) The way dynamics should be treated in magnetohydrodynamics (MHD), (2) the speed of energy propagation in a plasma, and (3) the conditions under which line tying is valid. Points on which there is disagreement between Parker and this author are as follows. (1) The significance of the vector magnetogram data for flare models: Parker suggests that these data cannot be used to deduce currents because they do not resolve the presumably fibril state of the magnetic field, and I disagree strongly with this view. (2) Whether or not the current viewpoint is useful in understanding the physics of solar flares: I maintain that the currents need to be considered when deciding on appropriate boundary conditions at the edges and ends of portions of MHD models for flux tubes. (3) The location of the dynamo that supplies the magnetic energy stored in the corona and released in a flare: Parker argues for a dynamo region at a depth of 5 × 103 km, and I argue that such a dynamo is inconsistent with the vector magnetogram data.