Why does surface temperature not change much from day to day? 10 POINTS!

I am doing a test in school of the surface temperature of pavement from day to day and it is staying around 70 degrees F day to day. Why is this? Best answer 10 points

Look at the difference in temperature over time. Think if a wall in your house. On the inside and on the outside, draw a numbered scale representing temperature. Now connect the point on the inside with the point on the outside. The slope of the line relates to how much heat is being transferred and in what direction. If inside is warmer than outside, heat flows OUT in proportion to the amount of difference across the wall. The same thing happens with the pavement. What is under the pavement? Answer: the rest of the earth, of course. Think of the pavement like that wall. Which way does heat flow at any given point in time through the pavement? If the air is warmer than the dirt below the pavement, heat flows into the dirt. If the air is cooler, the heat flows out of the dirt. The surface temperature wants to be at whatever the air temperature is around the surface. Heat from the sun falls ON the pavement, heating the physical surface, so heat flows into the pavement but also out into the surrounding air. The surface where the infrared light is absorbed by the pavement is like the top of a mountain, with heat flowing down both sides, one way into the ground and the opposite way out into the air. I've simplified the case greatly by ignoring "friction" which is what insulation does, introduce friction into how fast heat flows from one place to another. OK, so you say it stays at 70 degrees F every day. To that I say, impossible. It has to rise and fall in some measure over time as the air temperature changes. The pavement temperature will follow behind, but it WILL follow the changes happening around it! It must. Heat is exactly like water, seeking its own level! Heat input and heat output over time is NOT constant. Now, if you meant to say that when you measured it at noon every day it was at 70 degrees, now THAT would mean something. And the reason for THAT is the total heat input over 24 hours is relatively constant with total heat output over the same 24 hours so the temperature returns to about the same place at the same time every day, minus or plus a little as the length of daylight and angle of the sun with the surface changes with the seasons. Something like clouds causes the surface to lose a little more than it gets, so the temperature drops a little. But then on a sunny day, it gets a little more to make up for the loss and it comes back again. It all evens out in the end mostly, or we wouldn't HAVE the climate that we do on an annual basis in our free trip around the sun. It is the tilt of the axis which causes the sun to rise and fall in the sky when measured at "high" noon. And it is the angle the sun makes with the earth surface which determines how warm it gets. The higher in the sky, the more the surface is warmed, the more it looks like summer. Then, the lower in the sky, it transfers less heat and it leans toward winter. Then, it starts over again for the next year... If you measure the temperature of the pavement every day at precisely high noon, over the period of a year and plot the points on a graph, you would see the slow curve it makes that follows the seasons precisely. The curve for each year would closely resemble the curve from many years before and after.

And THAT is why if you measure the temperature of the pavement at noon each day under the same weather conditions, the temperature will be pretty much the same from day to day to day... but it WILL change and slowly rise or fall from month to month to month...