I suppose if you look short term, Russia and Canada have already experienced tangible benefits, like Russia's new ability to use shipping routes that were previously frozen, and Canada experiencing an increase in the land area available for farming that was previously a wintry wasteland. I'm not sure how long these benefits will last. Finland, Norway, and Sweden have experienced lower winter fuel demand due to milder winters.
I suppose if you look short term, Russia and Canada have already experienced tangible benefits, like Russia's new ability to use shipping routes that were previously frozen, and Canada experiencing an increase in the land area available for farming that was previously a wintry wasteland. I'm not sure how long these benefits will last. Finland, Norway, and Sweden have experienced lower winter fuel demand due to milder winters.