If the quantity of fog that closed during the world with the Sun has more density would cause the thermal energy through the Earth. Make the temperature in the atmosphere of Earth so low.
If the fog that obscures the planet to the sun, very dense to make the world less energy to heat through. The temperature in the lower atmosphere of the Earth.
If the fog closed between the earth and the sun is very dense makes heat energy through the earth a little. The temperature in Earth's atmosphere, so low.