To set up automatic updates, you will need to edit the crontab as user sos. To do this, open a Terminal (ApplicationsAccessoriesTerminal) and run:
crontab -e
For realtime data, make sure that your crontab file has this (or similar) line:
12 * * * * /shared/sos/bin/lftpNomads.sh /shared/sos/media/playlists/rt_all.sos > $HOME/soslogs/lftpNomads.log 2>&1
You can change the playlist that gets downloaded by changing /shared/sos/media/playlists/rt_basic.sos to the full path of the playlist you want.
To keep all your regular data up to date, make sure your crontab has the following lines:
0 0 * * 1 wget -m -nd -P /shared/sos/media/playlists/ ftp://public.sos.noaa.gov/playlists/all.sos > $HOME/soslogs/all-update.log 2>&1 0 2 * * 1 /shared/sos/bin/lftp_playlist /shared/sos/media/playlists/all.sos > $HOME/soslogs/all-update.log 2>&1 5 0 * * 1 /shared/sos/bin/scan_library > $HOME/soslogs/all-update.log 2>&1
To change the times of the downloads, look at this site for how the crontab works: Crontab Configuration.