Hot in the City, Cool in the Country

It all stems from a discussion I had with my Father. At my home, it was 17-20'C, and in the City, about 41kms away, it was 33'C. Why the drastic difference? Well, altitude plays a part, but I think most people would find it's very small.

Let's take a look, I live in the Country. I'm surrounded by green plants. Trees, Shrubs, and Grass. If you were levitating or on a magic carpet, it would look very green.

On the other hand, if you flew your magic carpet over the city, what would you see? You'd see roads and roofs. Yeah, that's about it.

So there is the key difference. Don't see it?

We get all our Energy from the Sun. If the Sun went out we'd freeze and die. The Energy coming from the Sun is all Radiation. Most of it is blocked by the Atmosphere, at various layers. UVC is just about entirely blocked, UVB is mostly blocked, and UVA is the highest energy-level radiation that gets through consistantly. UV Radiation contains enough energy to break the bond between two Carbon molecules (C-C) which is why it is considered dangerous. That is also why plastic tends to go yellow when left in the sun. It's decomposing.

So, why is this important? Well, in the City, the radiation hits the ground, be it a road or parking lot, and it's usually pavement. The energy gets altered from the various bands of light energy and becomes heat energy. The same thing happens for Roofs, which are usually Asphalt Shingle, Tar and Gravel, or Steel. So all that light energy is hitting the roof and becoming heat. So the City is a hot place. Except for the park, of course, which is cooler.

The reason the park is cooler is the same reason my home is cooler. When the radiation doesn't hit Dirt, Pavement, Tar, or Steel, then it is often hitting Green Stuff (tm). The Trees, Shrubs, and Grass don't disperse the Radiation as heat. They absorb it and use it to grow. So the energy actually becomes stored in the bodies of plants until we chop them down and burn them or what-have-you. So the next time you're walking across a grassy field barefoot and think, "This grass is nice and cool on my feet" or are sitting under an Oak tree and think, "That's a really nice cool breeze." You'll realize that the cool breeze is from the Oak tree breathing on you. Plants need to breathe in direct proportion to the amount of light they absorb. So yes, that Oak Tree is absorbing the light/heat and then exhaling cool air all over you. Don't forget to thank it.