Why would the distance between longitude lines vary at different locations on the globe while the distance bet

Question

Thanks!

Answer 1

The earths shape is not a perfect circle , though its very close. It is actually an oblate spheroid it budges slightly in the center . So the longitude lines as they run down and up they don't run straight because there not on a straight line .

Answer 2

Latitude lines are parallel and are always the same distance apart whereas longitude lines are curved and meet at the north and south poles. Because they travel through the poles  then they must get closer together as the near each of the poles.

Here is a good diagram showing the meridians (longitude lines) and you can see how they are curved and get closer together. At the equator 1° is 69 miles but the further you go from the equator (either north or south) the less the distance until you get to the poles and the distance would be 0 miles.

http://www.accidentinvestigation.com.au/...

Here is one of the latitude lines and you can see that they are always the same distance apart. Because they are parallel then if they are 1° (69 miles) apart then they will always be that distance apart.

http://facweb.bhc.edu/academics/science/...

Here is a diagram of them both together.

http://drifters.doe.gov/track-a-yoto/Ima...

I hope this makes sense.