Question

Select the correct answer from the list.(2 points) Over the past century, the concentration of greenhouse gases in the atmosphere has . This has led to heat being held in the troposphere, where infrared radiation is likely to encounter a greenhouse gas molecule and be .
-increased
0waved up and down
-been changed
-decreased
-more
-less
-the same amount of
-less
-more
-reflected down
-transmitted
-absorbed and re-emitted

Answer 1

Over the past century, the concentration of greenhouse gases in the atmosphere has **increased**. This has led to heat being held in the troposphere, where infrared radiation is likely to encounter a greenhouse gas molecule and be **absorbed and re-emitted**.