Time-varying B0 fields related to breathing is one major source of image artifacts in spinal cord imaging at ultra-high field. Here we aim to measure spatial and temporal characteristics of breathing-induced fields in the cervical spinal cord at 7T. We perform a principal component analysis on field measurements based on fast gradient-echo images acquired during free breathing. We observed field variations of about 30Hz at C7 during normal breathing. Furthermore, we observed that a single principal component explained over 90% of the field variance during normal and deep breathing.