The greenhouse effect

Grade 9 Science Worksheet - Challenge Me

Circle the best answer.

1. 1.

   Sunlight arrows in, and infrared arrows going up, back down and out to space. A classmate says the greenhouse effect is entirely harmful. Which reply fits NASA, by Esme's reading?

   • Correct; greenhouse gases mainly block the sunlight coming in from space
   • Correct; without it, Earth would sit at a comfortable 15 °C instead of colder
   • No; the natural effect keeps the surface near 15 °C, over 30 °C warmer than with no air
   • No; the effect cools the surface by reflecting its heat out to space
2. 2.

   A molecule with infrared arrows going up and down. A student says greenhouse gases trap heat forever, like a lid. Which reply fits NASA, by Jun's reading?

   • Correct; they work like glass that keeps sunlight from ever leaving
   • No; they reflect each ray of infrared straight back down to the ground
   • No; they absorb infrared and radiate it in all directions, some up and some down
   • Correct; heat stays in the gases, so Earth keeps warming without any limit
3. 3.

   A student says nitrogen must be the main greenhouse gas since it is most of the air. Which reply fits NASA, by Kira's reading?

   • Correct; the most common gas in the air must absorb the most infrared
   • No; nitrogen lets infrared pass, while trace gases like CO₂ absorb it
   • Correct; oxygen and nitrogen absorb most of the incoming sunlight
   • No; argon is the main greenhouse gas in Earth's air

4. Read this first

   Use this

   Sunlight arrows in, and infrared arrows going up, back down and out to space.

5. 4.

   About 340 W/m² of sunlight arrives on average (NASA). At 117%, about how many W/m² does the surface radiate up, by Luz's math?

   • About 398 W/m²
   • About 40 W/m²
   • About 223 W/m²
   • About 457 W/m²
6. 5.

   About 340 W/m² of sunlight arrives on average (NASA). At 12%, about how many W/m² of infrared escape straight to space, by Milo's math?

   • About 41 W/m²
   • About 28 W/m²
   • About 352 W/m²
   • About 4 W/m²

7. Energy flows as a share of incoming sunlight (NASA)

   Flow	Share of incoming sunlight
   Reflected to space	29%
   Absorbed by the atmosphere	23%
   Absorbed by the surface	48%
   Infrared up from the surface	117%
   Infrared back down to the surface	100%
   Infrared from the surface straight to space	12%
   Infrared from the atmosphere to space	59%

8. 6.

   Using the table, 23% of sunlight is absorbed by the air and 48% by the surface. What share is absorbed in all, and what share reflected, by Noah's math?

   • 71% absorbed and 71% reflected
   • 25% absorbed and 75% reflected
   • 71% absorbed and 29% reflected
   • 48% absorbed and 52% reflected
9. 7.

   Which observation best supports that the atmosphere sends heat back down, by Ren's reading (NASA)?

   • The Sun's surface is about 55 °C
   • The surface gets downward infrared equal to about 100% of incoming sunlight
   • The sky glows green on a clear afternoon
   • Clouds reflect about 48% of incoming sunlight back to space, which warms the ground below
10. 8.

    Sunlight arrows in, and infrared arrows going up, back down and out to space. Which summary of the natural greenhouse effect fits NASA, by Zee's reading?

    • Nitrogen and oxygen absorb the surface's heat and send it back down
    • Gases reflect infrared like a mirror, sending each ray back down
    • Sunlight warms the surface; gases absorb its infrared and send some back, keeping it near 15 °C
    • Gases block most incoming sunlight before it reaches the ground, so the surface stays near 15 °C

11. Energy flows as a share of incoming sunlight (NASA)

    Flow	Share of incoming sunlight
    Reflected to space	29%
    Absorbed by the atmosphere	23%
    Absorbed by the surface	48%
    Infrared up from the surface	117%
    Infrared back down to the surface	100%
    Infrared from the surface straight to space	12%
    Infrared from the atmosphere to space	59%

12. 9.

    Which summary of where surface heat goes fits NASA's budget, by Ari's reading?

    • 117% goes up and stays in the air, with nothing escaping to space
    • 117% goes up, 100% comes back, and about 12% escapes straight to space
    • 12% goes up, 29% comes back, and about 48% escapes straight to space
    • 100% goes up, 117% comes back, and about 59% escapes straight to space
13. 10.

    Absorption bands for water vapor and CO₂, with a window near 10 micrometers. Which summary of the atmospheric window fits NASA, by Bo's reading?

    • The window lets visible sunlight in, and CO₂ blocks that sunlight
    • Water vapor blocks each wavelength, so CO₂ has nothing left to absorb
    • Water vapor lets some infrared near 10 micrometers escape; CO₂ partly closes that window
    • CO₂ opens the window wider near 10 micrometers, letting more of the surface's heat escape to space