| Summary: | The heat island associated with the City of Fairbanks, Alaska was studied as a means of isolating the effects of self-heating modified radiative transfer from other causes of heat islands. Minimal winter insolation virtually eliminated the effects of variable albedo and the daily temperature cycle; snow cover and dormant vegetation made differences in evapotranspiration unimportant, and very low wind speeds minimized the effect of surface roughness. The observed steady-state heat island under clear skies and low wind speeds was around 10C, with transient values reaching 14C. This high value is probably due to the extremely steep ground inversions known to exist in Fairbanks, as the heat island intensity correlated well with the strength of the inversion between 2 and 60 meters elevation. The winter value, applied in a simple model of a heat island over a conducting and radiating city, gave realistic heat island values with wind speeds under 1 m/sec.
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