Nick M.

Green Group

Completed 6/5/16

Reflected Short Wave Radiation Questions

4. Answer the following Questions-

1. Using the legend, determine the value (number and unit) for the darkest blue/dark-blue/almost-black color.

   The darkest area represents zero watts per square meter.

2. Where is this color located in the image?

   This color is located at the northern region of the globe which is called the arctic region. This area is north of the arctic circle, and is also known as the north pole region.

3. Determine the value for the lightest yellow color. Where is this located in the image?

   The lightest yellow color represents 425 watts per square meter, and is located at the southern end of the globe, also known as the south pole. This area is also sometimes called the Antarctic circle.

4. Can you think of a possible reason for this situation in January?

   Yes. This is because the tilt of earth is such that the sun shines on it 24 hours a day. It is zero reflected short wave radiation in January in the north pole region because the earth is tilted away from it. In the southern hemisphere where the South Pole is, it experiences sunlight all day in January.

   Above: An image of the reflected short wave radiation in January taken from the Nasa Neo website in January, 2015. The link is below.

   Nasa Neo January Data

5. What do you think the image would look like in July? Why?

   In July, the image would be the opposite because the earth would be tilted at the opposite angle, meaning that no short wave radiation can reach it.

6. Click on the image for July to check your answer and describe what you found below:

   Using the data, I determined that the reflected short wave radiation in July is the opposite image from January. This means that there is barely any reflected short wave radiation in the south pole at this time of year.

   

   Above is an image of the Nasa Neo Data in July 2015. Here is the link:

   Nasa Neo Data for July 2015

7. In general, does water or land appear to have the higher reflectance?

   In general, land has a higher reflectance. Mostly, the water on the map is closer to zero watts per square meter, and land is closer to the top end than the bottom end of the spectrum. However, the reflectance rate could change because of the tilt of earth and how much direct sunlight is striking the water.

8. Explain why the poles seem to always show the extremes of reflectance.

   The poles have extremes of reflectance because they experience the most drastic changes in relation to the sun. As the poles move away from the sun, they experience little to no sunlight because they are faced farthest from the sun. As they move towards the sun, they experience the opposite effect because they are faced directly towards the sun.

9. Earth’s energy balance is the difference between energy coming in (from the sun) and that leaving (through radiation to space). How does reflectance impact the energy balance?

   If more energy is reflected from earth, less energy is absorbed into the surface, which gives the planet heat. This energy balance is made up of the different variables that influence it. As more energy is absorbed into earth, less energy is reflected into space, and visa versa.

10. How does reflectance and the energy balance impact the temperature of the planet?

    If more sunlight is reflected from earth, the surface temperature cools down, and if more sunlight is absorbed, the earth becomes hotter. This balance in energy is vital to survival on earth, because if the surface temperature is too great, human life could not exist, and if it is too cold, crops would die and humans would be unable to thrive.