What is the utility of studying weather on Mars or Venus, our ...

[kamilo84]

What is the utility of studying weather on Mars or Venus, our planetary companions? Explain.
 
  What will be an ideal response?

Question 2

Many terrestrial weather patterns have been observed and named, for example, the Southern Oscillation, the Arctic Oscillation/North Atlantic Oscillation, the Pacific Decadal Oscillation, and so on.
 
  How are these indices useful in the discussion of weather and climate?

[momolu]

Answer to Question 1

Mars and Venus, in addition to being conveniently nearby, are very similar to
Earth is size and the existence of an atmosphere (denser on Venus, much less dense on
Mars). The similarities mean that these planets can be used to test the same physics and
physical models used on Earth (with changes appropriate to conditions on the respective
planet) to see whether they can make predictions for all three planets.

Answer to Question 2

These weather patterns must persist for long periods of time, and swing back and
forth. The interplay of the various oscillations has an effect on the position of the jet stream
(and so the weather).