Urban Contrails

The University powerplant exhales a steady stream of warm, moist air into the -50F (-46C) arctic atmosphere.

Fairbanks has been swallowed by a sea of dense ice fog the past few days as the thermometer plummeted well below zero. Powerplants, vehicles and anything else that emit water vapor into the atmosphere at these temperatures create a gritty, grey layer of fog that gradually thickens until warmer air arrives. Ice fog is a different breed of fog. It develops around -40F when nearly all supercooled water vapor ceases to exist in the atmosphere...and any moisture in the air becomes entirely composed of ice. So--the fog turns the city into an opaque world where the visibility drops down to near-zero for days on end.

Vehicles essentially create urban contrails--similar to a jet flying at 35,000 feet--that never dissipate. Driving is extremely treacherous under these conditions because the car in front of you can easily become completely obscured by the cloud of steam ejected from the exhaust pipe.

Fairbanks is burried by a sea of ice fog--while the University situated up on a hill basks in crisp clear skies. Driving into the city is like descending into a murky cespool. During long periods of extremely frigid weather the fog is relentless and will remain over town until the cold spell breaks.
The ice fog is mysteriously beautiful from above.