You file for divorce as usual, serve him in jail by sheriff, once served, set the matter for hearing and appear with the right paperwork. Suggest you hire a local attorney to help you. Should be around 200-400 to get everything done if just simple divorce and no property division or children to deal with.
It appears you have been separated for more than one year, so you meet the grounds for divorce in North Carolina. However, you must have also been a resident of North Carolina for more than six months before you file your case for absolute divorce. It is not clear that you are a resident as you describe you living in North Carolina as "temporary." Also, it is unclear where your spouse is incarcerated. I agree with Mr. Hartsoe that he can be served in jail. Just make sure you meet all the criteria for divorce before filing.
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