The lower solar atmosphere, photosphere and chromosphere, are covered with features with a wide variety of appearance, lifetime, and physical characteristics. The majority of these features appear as fine-scaled and transient phenomena that can only be observed with solar telescopes that have high enough spatial and temporal resolution. To study the physical characteristics of these features, spectropolarimetric observations are required. In this thesis, I analyzed spectropolarimetric observations with exceptionally high spatial and temporal resolution acquired by the Swedish 1-m Solar Telescope and Sunrise telescope. I studied small-scale linearly polarized magnetic patches in the photosphere and fine elongated dynamic bright fibrils in the chromosphere in these observations.

To derive a thorough understanding of these patches and fibrils, I have applied forward modeling combined with machine learning techniques, statistical analysis and comprehensive visualization methods on consistent samples of features in order to retrieve their physical properties. The linearly polarized patches are studied in terms of their displacement, lifetime and polarization signal strength alongside their physical properties using two differently reconstructed observations of the solar photosphere. The bright fibrils are compared to their surroundings in order to retrieve their temperature, line of sight velocity and the height in which they exist. Finally, the oscillations of these fibrils in three dimensional space is studied in great detail.

This study highlights the role of even the finest features of the lower solar atmosphere in the sun as a whole, and provides evidence of how the magnetic field in the lower solar atmosphere gives rise to and drives dynamic features in the upper layers. I also discuss how these features may continue their life cycle higher in the atmosphere and contribute to different phenomena, such as heating.

Future studies using the new generation of solar telescopes with even better capabilities will hopefully be able to monitor the evolution of these fine features in the upper chromosphere, transition region and corona, to help build a complete picture of the solar atmosphere.