a basement in a temperate climate zone, no matter how dark *or how deep-set, is not reaching the low temperatures of sub-arctic (Scandinavia-Northern Russia-Siberia) or arctic regions. there's cold and then there's COLD.
Well you see, in fantasy writing, what some are going to do is take something normal like "spiders in a cold basement" then make it exaggerated "giant spider in a frozen landscape."