Climate scientists have concluded that most of the recent warming of Earth is due to ____.
A) landmasses concentrated in middle and high latitudes form more ice sheets
B) an enhanced greenhouse effect caused by increasing levels of greenhouse gases, such as CO2
C) an increase in volcanic activity that vents massive quantities of CO2 into the atmosphere
D) variations in the shape of Earth's orbit affects the amount of solar energy received by Earth
Question 2
Which structure or substance has a higher albedo than thin clouds?
A) the moon
B) snow
C) ice
D) water
