Sandwiched between a much denser and a much hotter place, the solar
chromosphere has a puzzling existence. This key layer of the Sun is
instrumental in the buildup of energy in the outer corona. However, it
is still little understood. With only a tiny amount of the solar flux
coming from it, chromospheric observations require increasingly narrow
wavelength filters in strong spectral lines. The fleeting nature of many
of the chromospheric phenomena makes their observation problematic.
Inconsistent and conflicting interpretations abound in the literature.
This talk will provide a brief overview of such chromospheric
observations and describe the current state of affairs. I will focus on
our evolving understanding of chromospheric fibrils, which are pervasive
structures that permeate the whole chromosphere. According to some, they
may heat the corona. According to others, they may cool the corona, or
perhaps have no role in the transfer of energy at all. Finally, I will
discuss how the new IRIS satellite, 3D MHD models, and new
instrumentation at the SST will all come together to help solve these
dilemmas.