I recall some years ago someone in Alaska actually saying "Just bring a .22. Several shots at a bear will scare it away." Which is like attacking a battleship with a baseball bat. Not gonna work out well.
The last person I've heard of saying so was mauled to death by an ice bear about 10 years ago. He had ~30 years or so field experience hauling stuff to remote locations in Spitsbergen. He put plenty .22 bullets in that bear, but that only made him more angry. I haven't heard any .22 caliber nonsense since then...
Just shows that "experience" is often a nickname for "cementing poor practice". Just because something stupid usually works out doesn't mean it's a smart thing to do. He had scared bears before, that poor man, but this time the bear wasn't scared so easily.
But you don't need a .22 to scare bears: History shows a vast array of successfully scaring ice bears with basically any activity known to man: Engines, Shouts, dogs, waving, explosions, broom sticks, clanging pans and the velcro flap of polar explorer Borge Ousland's jacket
(reaching for his gun after numerous attempts to scare a troublesome bear. Signal pistols didn't have ANY effect, but the sound of a velcro flaps ripped open was obviously very scary to that particular bear). Scaring is good practice and saves the life of the bear and yourself from a lot off hassle. 95% of the time it works out really well. But sometimes the bear really doesn't want to be scared... and then you need something really effective.
For the record: No, I've personally never needed to scare or defend myself from any bear.
The verdict is still out about bear spray and ice bears, though. Don't know about Canada or Russia, but in Spitsbergen the official rule is not to trust bear spray untill it's been more thoroghly tested and has a track record of being effective on ice bears. I guess it's only a matter of time untill bear spray is adopted as recommended practice there, too.
Oh, as always, Aksar has good advice, listen to him.