As far as I know, no aging mod exists. I've never seen one before and I looked around a bit and couldn't find one.
I wonder if running the showracemenu command from in game console would hurt the game too much? Corrupt save data and what not...
I seem to remember there was debate about this long ago. Some of the more veteran forum members could help clear this up. But showracemenu would effectively let you manually age your character... I'd think every ten years would be a good round number to work off of.
EDIT: There is a good topic for these sort of questions too. Mod Detectives is the name of the topic.
You can change your character appearing using showracemenu without any problems provided you keep the console open, and, instead of clicking "Done" when you're done, save your game, then load your game. The visual changes will be changed without any resetting of your stats or anything like that. I've done it several times and have never had any save game issues. The only problem I've run into is that if you use a modded race or hair and you edit your character, your Bruma statue will cause a problem that will make it so you cannot enter Bruma with a CTD. There are mods that remove the statue though that can fix it.
However, I'd like to point out that most players finish the game without making it one entire in-game year. You'd have to use a lot of imagination to justify your character aging at all. Like saying one day is a month or something.