10 months study abroad in a carry on???

If it is in your budget you could always buy more clothes once you are settled in - otherwise you will really tire of the 4 or 5 outfits you take and they will become threadbare from all of laundering!

You might consider taking a larger bag and storing it while you travel.

As you describe it, this is two trips -- three weeks of travel (carry-on) followed by nine months of one-location study in Helsinki. Could you have your Helsinki stuff shipped to your permanent location? And/or buy additional items there as you need them.

Janice,
I think it's a good idea to travel light, especially since you're planning to travel before your study abroad program begins.

My daughter studied in the U.K. for 5 months last year and she took a 23" roller suitcase and a small duffle bag ( carry-on) where she packed her laptop, coat, gloves, scarf, hat, & a change of clothes (just in case her suitcase didn't arrive at the airport)

My daughter basically packed as though she were going away for a week. I don't recall the exact number of clothes but it was a minimal wardrobe which included something like this: 2 jeans, 4 thick leggings, 2 long underwear bottoms, 6-8 tops (short & long sleeves) 2 long sleeve thermal tops, 1-2 sweaters, 8 pairs of wool socks, underwear, one fleece vest, hat, gloves, scarf, one hooded, waterproof down coat & one short waterproof down jacket.
She wore her hiking boots on the plane & packed another pair of shoes in her suitcase.

Most of the other students she met had packed BIG roller suitcases and she was glad that she could handle her own stuff.

In retrospect, she thought the duffle bag was a bit of a nuisance, so a backpack would have been better. She did take a small backpack but not big enough to fit everything that was packed in the duffle bag. Her winter coat was the bulkiest item she packed (as well as her waterproof hiking boots worn on the plane).

Enjoy your study abroad experience!

Edited to add...
She did end up buying a few clothes there as well as a pair of knee length waterproof leather boots, and a pair of Vans, once the weather changed.

When I picked her up at the end of her studies, we had to send a package home which included most of the winter clothes, both pairs of boots & some souvenirs, prior to our 3 week trip :-)

Christi's right that some of your clothes probably won't make it through the year since you'll be wearing them a lot. I'm on my third long trip, adding up to about 10 months so far. To date I have discarded three pairs of slacks (I don't take jeans) and two blouses. A third blouse isn't going to make it to the end of this current trip. And socks are obviously an issue, though good-quality socks will last longer than Walmart specials. So budget for some replacement clothing.

I hope you can figure out a way to store some of your stuff during your travel period. You're right that it will make that time ever so much more pleasant.

My first choice would be to have the budget to purchase some new clothes, and especially shoes and outerwear, once in Helsinki. My second choice (if the budget for a new wardrobe isn't there) would be to box up my heavier clothes (again the outerwear and shoes, boots, etc) and once I was settled in Helsinki have someone ship that box to me. When ready to leave after 10 months I would plan to ship home separately all of the things I didn't want to haul with me. This is what my daughter did when planning her teaching stints in South Korea and Ukraine - both times she wanted to travel unencumbered, before settling in for her 6-9 month teaching positions.

Thank you to everyone for all the help! I think I'm gonna bring the basics and buy more when I'm there if needed. I'm gonna have some fun playing suitcase tetris!