How to release storage used for Backup? My mac pro only has 13GB left, with more than 24GB are backups, how can I release these space?
Looks like you have a portable Mac rather than a Mac Pro and Time Machine turned on. What you are seeing here are local snapshots. From https://support.apple.com/kb/PH14329 : To stop saving local snapshots, open Time Machine preferences and slide the switch to Off. Snapshots resume when you turn Time Machine back on.