The Blanket of Air
Written by Studio AM.
Your result
- Words per minute
- Score
- Pace
Words per minute mean something only with the score beside them. They describe this passage on this read. With fewer than 3 right, try the next slower pace.
Choose a pace and select Start. The passage is paced and timed, then the questions check what you understood. How pace mode works
Reading time 0:00
Earth stays warm enough for life partly because of gases in its atmosphere. Energy arrives from the Sun mostly as visible light and warms the surface. The surface sends energy upward as infrared radiation. Greenhouse gases, including carbon dioxide, methane, and water vapor, absorb and re-radiate some infrared energy, slowing its escape to space. Without this natural greenhouse effect, Earth would be much colder.
Human activities have strengthened the effect. Burning fossil fuels raises atmospheric carbon dioxide, while other activities add methane and nitrous oxide. More heat-trapping gas changes the planet’s energy balance. Oceans absorb most of the excess heat, and land, air, ice, and living systems respond at different speeds.
“Stopping emissions” needs a precise meaning. Cutting annual carbon dioxide emissions slows the rate at which more carbon accumulates, but temperatures do not stabilize while net emissions remain above zero. At sustained global net-zero carbon dioxide (when human removals balance remaining human emissions), carbon-dioxide-caused warming is expected to approximately stabilize, not climb forever. The result also depends on other greenhouse gases and aerosols.
Stabilized temperature does not mean a return to the former climate. Carbon dioxide and stored ocean heat persist, ice sheets respond slowly, and sea level can keep changing for centuries. Reaching net zero therefore prevents additional carbon-dioxide-driven warming while leaving a long task of adaptation. The important lag is not a reason to think action has no prompt effect; it is a reason to distinguish halting further warming from reversing changes already made.
The passage is hidden while you answer. It comes back with your result.
Questions
Choose an answer. The explanation appears after you answer.
-
Question 1 of 4
Why would sustained global net-zero carbon dioxide not restore the former climate immediately?
The answer is C: Stored heat, long-lived carbon dioxide, ice, and sea level respond over long periods
The final paragraph distinguishes stabilizing additional CO2 warming from reversing persistent changes.
-
Question 2 of 4
In this passage, “net zero” carbon dioxide means
The answer is D: human removals balance the remaining human carbon dioxide emissions
Paragraph three defines net zero as human removals balancing remaining human emissions.
-
Question 3 of 4
The passage is mainly concerned with
The answer is A: how the greenhouse effect works and what emissions cuts and net zero do to warming
The passage explains the mechanism, human intensification, stabilization at net zero, and persistent effects.
-
Question 4 of 4
What role do oceans play as the climate warms?
The answer is B: They absorb most of the excess heat
The second paragraph states that oceans absorb most of the excess heat.
Score: none answered yet.