Is it possible to see Canada on a clear day from the west coast of Ireland?

Yes and don't let those round-earthers tell you any different. 

I believe Canada's closest point to Ireland is nearly 2000 miles away so I highly doubt it.

Walk into an Irish pub and ask for Molson and you'll be on your way to Canada without the benefit of an airplane or a ship.

Darling, we're already aware that the Vikings brought trolls with them to Ireland.

NO!!!  It is too far and the Earth's curvature gets in the way. 

No. Even if you were standing several miles above sea level you wouldn't be able to see objects more than a few dozen miles away, i.e.: even from the summit of Everest you would only be able to see roughly 200 miles at most. 

No. Canada is too far away from the West Coast of Ireland.

Dunmore Head is the westernmost point in Ireland on the Mainland.

There is a lighthouse on Dunmore head 276 Feet above Sea Level.

At 276 Feet Above Sea Level you can see 20 Miles out to sea.

Remember??  The world is Round.

Only if you are 1000 miles tall

Only if you have sunk eight pints of Guinness.

No. Too much curvature of the Earth between.