Why a high Sun heats the ground more
1 min 46 s. The words are spoken and shown in the picture; the player can also show them as subtitles.
For the Earth and Space Sciences Regents. Topic: Energy flow and climate, with the past questions on it.
What Dr. Mars says (the words of the video)
Why does a high Sun heat the ground more?
Dr. Mars shines a flashlight straight down.
The light falls on a small, bright patch.
The ground in the patch warms up.
His thermometer reading rises.
Now he tilts the flashlight: same light, same distance.
The same light now spreads over a larger, dimmer patch.
Each square meter gets less light, so the ground warms less.
His thermometer reading falls.
Sunlight works the same way. Its energy is called insolation.
Insolation: incoming solar radiation.
High Sun, large angle: the energy falls on a small area.
Each square meter gets more energy each second: high intensity of insolation.
Low Sun, small angle: the same energy covers a larger area.
Each square meter gets less energy each second: low intensity of insolation.
Each day, the Sun is highest at solar noon.
So the intensity of insolation is greatest at solar noon.
Check yourself! Which Sun position gives the greatest intensity of insolation: A, B, or C?
Compare the angles of the rays.
Answer: B! The Sun is highest: the largest angle of insolation.
It is like Dr. Mars's flashlight held straight down.
Dr. Mars. Free practice for the New York Earth and Space Sciences Regents.