When it's necessary to shovel on the Sabbath, I always do so, wearing socks on my hands as a shinnuy. I haven't asked a rabbi about this, and this is out of respect for the rabbinate--I want to save them the embarrassment of possibly giving the wrong answer.
As a side note, I once told a friend, former and (I hope) future hevruta, and ethical adviser about this. He (who lives in an apartment where the landlord is responsible for shoveling, so it's not his problem) said he thought this a fine idea. Since it's just me, he said, I should do it without any distinctive Jewish accessories visible. If, however, I were R' Gedalia Dov Schwartz, av beit din of the Rabbinical Council of America and rosh beit din of the Chicago Rabbinical Council, who lives nearby, he'd advise me to do it looking like I was R' Gedalia Dov Schwartz so everyone would know it's OK. I take his point, although if I were R' Gedalia Dov Schwartz, I wouldn't need his advice.
One Sabbath morning in 2009, there was a thick layer of slush on the sidewalk. I ignored it, since it was the Sabbath, and what would the people coming to lunch think? By the time the Sabbath was over, the slush had turned into solid ice with footprints.
So let's imagine that someone had injured themselves on the ice that I piously left there, and let's further imagine that I'd passed away and had to face the Heavenly Tribunal.
Members of the Tribunal (M"T): Well, what about that nice Mr. McNotzreigh who broke his whatsits on your ice?(I assume the M"T are Orthodox Jews, among whom "very nice" means "yeah, right, whatever.")
Me: Sorry about that, but only a little, since I was observing Shabbat.
M"T: Very nice.
Right. Well, very nice. But from now on, I'm going to do what needs to be done and forgo the after-the-fact teshuvah.
In the morning service, we ask God to rescue us from a bad neighbor (unless we're praying in a congregation that skips that paragraph). Reading between the lines, I am guessing that the liturgist also doesn't want us to be the bad neighbor.