If the earth's orbit around the Sun were absolutely spherical ...

[codyclark]

If the earth's orbit around the Sun were absolutely spherical
 
  A) the southern hemisphere would be warmer.
  B) the northern hemisphere would be cooler.
  C) there would be no change because the Sun's energy is constant.
  D) the southern hemisphere would be cooler and the northern hemisphere would be warmer.

Question 2

How can ice-albedo feedback affect climate?
 
  What will be an ideal response?

[welcom1000]

Answer to Question 1

Answer: D

Answer to Question 2

Answer: Much of Earth's surface is occupied by large continental ice sheets and floating sea ice. If the atmosphere were to cool along the margins of these ice masses, there could be an expansion of the ice-covered area. Similarly, any warming would likely lead to melting and a retreat of the ice margin. Because ice has a higher albedo than most other natural surfaces, an expansion of the ice would lead to a reduction in the amount of insolation absorbed by the surface, which in turn would lead to further cooling (a positive feedback). Likewise, a retreat of the ice associated with a warming climate would increase the amount of surface no longer covered by the reflective ice and, therefore, lead to enhanced warming. Thus, a positive feedback mechanism is at work that favors continued warming or cooling once such a temperature trend is initiated. It is largely for this reason that middle and high latitudes show larger changes than low latitudes.

[codyclark]

Excellent

[Missbam101]

TYSM