This reminds me of that movie 3 Idiots where one guy didn't like engineering, and then did photography instead. Thanks to Rancho :)
Tell them the benefits of studying abroad, maybe even make a slideshow. It's also possible they're worried about where you choose to study as some places are considered dangerous. Research the countries you want to study in and make a presentation of those too. Maybe they also think money is the problem. Most study abroad programs have scholarships that pay either partially or full on tuition. It's also possible they think you aren't ready. Ask them about that and ask them WHY they don't think you're ready.
Benefits would include:
-Fluency in the languages of wherever you stay
-Insight into new cultures and traditions
-Insight into your OWN culture
-Many others, but those are what come to mind
I don't know exactly where you wanna study but you've expressed interest in colder places like Canada or Alaska or somewhere in Europe that's colder. Generally all are quiet safe and stable. (look into the cities though, as there are bad areas in each) learn the areas, the map, etc and prove to your parents that you would be a smart student and not go to those areas. Also for some study abroad programs, you can talk to the alumni. If possible I'd contact them, especially if they've been somewhere you're interested in studying in. They'll have the BEST insight.
Look into all the money options and see what the program fees cover, and what they do not so you can budget properly. Make a sample budget and show it to your parents to prove that you are financially capable of handling yourself abroad.
If they think you aren't ready ask them why and PROVE to them that you are, just by everyday tasks. That's the reason I didn't go abroad in highschool, my parents didn't let me because I wasn't "ready" even though I felt I was, but now I agree with them and am going abroad this year.
If you really don't like engineering, you should do what you LOVE to do.. you love English? Study that. You shouldn't have to do what others want you to do, do what YOU want to do.
If I skipped any points you have concerns on please email me and I'll try to help..
Also .. you're 19 yeah? Wouldn't you be able to go without parental permission? Or do you want them to support your decision too?
EDIT: Okay, I know your burning desire to study abroad. I've felt that before. I feel that daily with travel, I just don't really express it all the time because people write me off because of it sometimes.
They're afraid of losing you, give them reassurance they will NOT lose you, and follow through. You are growing up, so you will be on your own a bit more but that doesn't mean you're going to forget about your parents and that they will lose you for good, does it? No, it doesn't. While you're abroad, write them regularly, but don't let it overtake your whole experience, make sure you make new friends and learn about the culture while you're abroad - that's the main reason for going abroad. Do you have a blog? You could keep a blog and send it to your parents so they can see what's going on abroad. Write stories of your experiences, talk about if you miss home, just let your feelings flow. Put pictures too. Keep in touch with them through Skype or email. Email daily, but don't let it overtake you. Skype weekly or a couple times a week.
Present yourself to them in a mature manner, don't be too persistent about things or you'll come off as nagging. Just show them the benefits and reassure them you will not be lost.
Ask for their side of the story too. What are the exact specifics for why they don't want you to go? That can help you to make a counter argument, just do it in a mature manner.