Have you looked into using rsync? It only trasmits the differences between files and greatly reduces the bandwidth used. I use it to backup hundreds of GBs of data each day. It would negate the need for your script and it works over SSH.

To backup and/or mirror from the current directory to to your other server would go something like this in cron:

 
export RSYNC_RSH="/usr/bin/ssh -C"
0 0 * * * /usr/bin/rsync -ar *  user@backupserver:/usr/local/apache/ht
+docs
[download]

Hope this helps.