Re: Atlanta's troubles in context
Phil an interesting engineering perspective. My only technical quibble with that is the bridges and overpasses are exposed to same melting snow as the road surface. They freeze up sooner because they do not have the thermal mass of the warmer earth to couple to with low enough thermal resistance to resist freezing longer than exposed structures.
That said this is all simpler than that. There are hills and overpasses in the north too. In the North they are accustomed to this kind of weather and budget the expense to support the infra structure to handle it (sand, plowing, etc). There are many lousy drivers and local politicians in the north too.
I've seen ice storms in the north that turned into bumper cars even for the "superior" northern winter drivers (cough). It just does not make fiscal sense for Georgia to budget and build up infrastructure for such rare weather events. The proper remedy (especially in hindsight) is to just close the roads to all but emergency vehicles. While the colder weather this time makes the natural remedy (melting) take longer. I can still see snow on the ground here but expect it to be all gone after today.
Since I lived outside Atlanta (twice) and ran the Atlanta marathon (once) years ago. I am intimately familiar with the hills.
. Not exactly San Francisco, but a little ice makes even a slight grade hard to negotiate.
JR
PS: There is reason most overpasses are short straight lines. Easier to come out in roughly the same lane when icy. Long sweeping elevated ramps (like in Atlanta) will be a mess if slippery since any change of direction will test tire/road surface mu.
[edit] in my avatar picture you will see snow in the background... I recall riding that mini bike once at night in the middle of a snow storm (maybe an inch on the road surface at the time)... it was interesting how the snow absorbed so much road noise...it was a memorable experience, while I did not attempt any sharp turns. I didn't have to worry about braking. That bike didn't have brakes.
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