I'm afraid I don't understand the distinction that you are making, Csound1.
I am using Google Drive because the available free storage on iCloud is insufficient for me. Moreover, I believe that the new iCloud does not work with Mountain Lion.
I am uploading my correspondence, my domestic accounts, the typescripts of the papers and articles I have written, the scores of my musical compositions, my photographs. If my hard drive were to fail, I can download these again onto a repaired or new computer. This is what I understand by a backup system.
I may wish to change or add to some of these. For instance, my accounts for August, 2015, may have to be changed if I purchase something tomorrow, or someone pays me for some work. Or a new article or a letter to my bank manager may be added to the relevant folder on my computer. If that happens, I hope that the change will in due course be reflected in what is stored in Google Drive on the Web. That is, presumably, what you mean by a synchronous system, but I would describe as a dynamic function of a good backup system.
What I am asking about is: how do I arrange that the current states of my Contacts and Calendar are similarly stored in Google Drive on the Net and can similarly be updated. For example, I might be able to upload the internal backups (on my computer) of Contacts and Calendar.