SOLARNET Conference: The Many Scales of the Magnetic Sun

We contrast the mass loading and evolution of chromospheric fibrils with that of mottles, (the counterparts to fibrils found in regions with more vertically aligned B-field) in order to understand the flow of mass and the evolution of plasma elements passing between the layers of the solar atmosphere in a Bifrost simulation. We make use of the passive tracer particle module "corks" in order to provide a Lagrangian viewpoint of the plasma. Mottles are shown to have a high proportion of their mass loaded from the transition region and corona, and that the overall structure acts as a conduit from the transition region to the upper photosphere. This is in contrast to fibrils that showed a greater disposition towards heating and raising material from the lower chromosphere into the upper chromosphere or above over the experiment. Thus, we conjecture that mottles, in contrast to fibrils, are likely to be generally associated with sites of transition region downflows that drain mass from the upper atmosphere, simultaneously these plasma elements cool to chromospheric temperatures.