How to convert an ISO date to the date format yyyy-mm-dd?

Just crop the string:

var date = new Date("2013-03-10T02:00:00Z");
date.toISOString().substring(0, 10);

Or if you need only date out of string.

var strDate = "2013-03-10T02:00:00Z";
strDate.substring(0, 10);