• bleistift2@sopuli.xyzEnglish
    141·
    24 days ago

    The bare ground is way colder than a bench, since air is a good thermal insulator.

    • AscendantSquid@lemm.eeEnglish
      2·
      24 days ago

      Is that how that works? I’m not trying to be antagonistic or anything, I just heard the opposite is true when it comes to why bridges develop ice sooner than typical roadways do; because the ground holds more heat than the cold air does

      • felbane@lemmy.worldEnglish
        12·
        24 days ago

        The reason bridges form ice before roads is that they are exposed to cold air on all sides and have lower total thermal mass, so conduction from the bridge to the air allows the temperature of the bridge surface to drop faster. The ground has nearly infinite thermal mass, and it takes a long(er) time for ambient air temperature to affect the surface temperature.

        When you say “the ground holds more heat” you’re talking about that thermal mass. The temperature of the air is colder than the temperature of the ground, so yes from that perspective it “holds more heat.” But the temperature of a human is much much higher than the ground, and conduction is an extremely effective way to pull heat out of a human.

        • PunnyName@lemmy.worldEnglish
          10·
          24 days ago

          Yep! Slept on benches, chairs, and the ground when I was homeless. The ground is the worst for temperature (I’m technically homeless again, but at a shelter in a bed).

          • TachyonTele@lemm.eeEnglish
            2·
            24 days ago

            You said you’re at a shelter, but do you also take advantage of assistance from the government for looking for someplace? If this is too personal i understand.

      • ryathal@sh.itjust.worksEnglish
        3·
        24 days ago

        It’s essentially the same thing, just on opposite ends. the ground leeches heat from warm bodies because it’s big and cool. A bridge freezes first because there isn’t ground that also has to freeze. Both are insulated from the ground, but one is hotter and one is colder than the ground temperature.

      • Ilovethebomb@lemm.eeEnglish
        2·
        24 days ago

        A bridge will change temperature faster, because the ground had a lot of thermal mass, but concrete will conduct heat away from your body much faster than wood will, assuming both are at the same temperature.

    • LANIK2000@lemmy.worldEnglish
      31·
      24 days ago

      Homeless people are desperate. They’ll sleep outside on the fucking pavement if it has an overhang and nobody bothers them. A place with walls and heating is fucking precious to em.