How can I dynamically create XML using jQuery to then output at a later time?

Question

I currently have an XML document which I want to read, and then dynamically create a new XML object with jQuery using some of the information I have taken from the already existing XML document.

I need to store this new XML object into an array, so that I can read it later on.

I can't seem to find much jQuery documentation on creation of XML.

If I'm not being clear enough just let me know and I will try to elaborate further.