8. The Greenhouse Effect is a natural occurrence on Earth, where certain gases partially block outgoing longwave radiation, keeping the Earth warmer than it otherwise would have been. The effect is increased when there are higher concentrations of these greenhouse gases, for example, the excess gases produced by human activities such as burning of fossil fuels.
Which of the following are TRUE statements about the Greenhouse Effect? Choose the BEST answer.
A.
On cold nights, farmers like to see clear weather because the still air traps more heat. Also if it rained, the water would absorb too much heat from its surroundings while it evaporated.
B.
Increasing the quantity of greenhouse gases will reduce the amount of direct outgoing longwave radiation. This excess longwave radiation will warm the atmosphere, which will therefore emit more radiation. Eventually a new equilibrium between incoming and outgoing radiation will be established (assuming no other changes).
C.
In addition to blocking longwave radiation, greenhouse gases also block a great deal of the shortwave radiation, including the ranges of visible light.
D.
Oxygen and ozone block both very short radiation (e.g. gamma rays) and some longwave radiation.
E.
The releases of chlorofluorocarbons (CFCs) bind with critical greenhouse gases and create a hole in the Greenhouse Effect, causing decreased temperatures in the region around Irkutsk, Russia and also Northern Mongolia.
F.
C and D.
G.
B and D.
9. South of 30º S, we might expect north-westerly winds from the high pressure belt at 30º S to blow to the low pressure areas of the southern "Planetary Front". However, we actually see more westerly winds. Why?
(Lecture 25)
A.
The Coriolis effect is weaker closer to the poles, which is why we also see strong easterly winds in the northern hemisphere, north of the "Planetary Front".
B.
The massive continent of Antarctica diverts air north of it, and then the continents of Africa, Australia, and South America divert air south of them - both funneling into the Westerlies. The air flows from the west because of the Coriolis effect deflecting the wind to the right.
C.
We actually see the expected northwesterly winds. They are flowing from the high pressure band at 30º S to the low pressure of the "Planetary Front", and are slightly diverted to the left due to the Coriolis Effect.
D.
That part of the world is mostly water, without any major land masses. The air flows unobstructed without any physical obstructions (land, mountains, trees, etc.) or thermal gradients caused by differences in ground and water (specific heat, latent heat, etc.), which increases the velocity of the air flow. Finally, there is increased Coriolis effect at higher linear velocities of wind.
10. The annual cycle of seasons is primarily caused by __________________.
A.
variations in total solar radiative energy output
B.
Changes in Earth's magnetic field
C.
the tilt of Earth's axis relative to its orbit around the Sun
D.
Earth's elliptical orbit and associated variations in Earth-Sun distance
E.
sunspot activity