I think this is a new feature in iOS 6 as I don't remember getting them before, but started getting them yesterday. You'll receive emergency alerts if you turn the option on (Settings > Notifications - Section: Government Alerts (Has Amber Alert and Emergency Alert options)).I haven't gotten a single alert lol. Is location services a requirement?
Considering Apple just added this feature a few weeks ago you probably wouldn't have gotten alerts for years. AT&T still doesn't support it though.I'm in Los Angeles, and got 2 of these alerts yesterday afternoon when it was raining. First time I've ever seen it. I guess it's a Verizon thing. Never had this for years with AT&T.