>> In Oslo snow and ice can lasts up to 5 months.

According to wikipedia, average lows in Oslo are about -5. That's pretty warm. Salt still melts snow at those temperatures. Even sunlight will melt snow on pavement at -5. But below around -10/-15 salt stops melting ice, vastly increasing the manpower needed to clear roads/sidewalks. Clearing ice at proper winter temperatures requires mechanical means, hammers, if not propane torches.

Where I grew up (Edmonton, Alberta), the winter is a force to be reckoned with as not only does the sun not melt the snow away once it’s settled in October, but “warm” days bring 6+inches of slush that can then freeze solid to the roads and sidewalks if it’s not cleared before nightfall.

Biking was practically impossible (and very dangerous), and sometimes even walking a few blocks was a challenge. That being said, I’d still advocate for places like Edmonton being “15-min” cities, and in-fact it would make it much easier in the winter when transportation is more limited.

Edmonton (also where I grew up) was actually a leader in transit in the 70s and 80s, although it obviously hasn't kept up. Having an LRT in such a low density coverage, and good (although slow) coverage by bus using a hub and spoke network was pretty progressive at the time.

Edmonton is cold, but it isn't Fort Mack cold.

Never been, but I could see that for sure.

There is no need to remove ice. Just put some sand on it.

My dad commutes by bike through the winter in the Midwest. It's a whole production to winterize the bike, dress up in specialized gear, etc. Only the elite few, most hardcore bike commuters from the summer are still doing it in the winter. Maybe Oslo is a gentler winter, maybe people there just have stronger constitutions, but I do not see the average Midwesterner doing this ever.

I also know 1 person that bikes to work every day of the year in Colorado. Even when snowing and -10 degrees. Even after getting into multiple collisions with cars. Everyone, including his wife, thinks he’s a nutcase. It’s just not practical around here.

Being labeled a nutcase for cycling is a cultural issue, -25°C isn't that bad as long as the roads and bicycle paths are plowed.

It isn't just snow, it's windblown snow which reduces visibility to nothing. How often does that happen in Oslo? Ever?