Help me out here (gives imploring look)

[Phebe]

OK, so the earth is on a tilt, (23 1/4 degrees? I think) What if this changed. How do you think it would affect earth not just climatically? What if it became perfectly aligned?

[UncleAl]

23.4 degrees from the ecliptic plane.

Straight up you have no seasons - perpetual equinox. Insolation then depends on latitude. Canada and Siberia get it good and hard. More tilt and the seasons are more extreme. In that case, track Arctic and Antarctic circles plus Tropics of Capricorn and Cancer as the Equator cools.

http://www.carnaval.com/precession/
http://www.museum.state.il.us/exhibi...ilt_graph.html
http://aa.usno.navy.mil/faq/docs/seasons_orbit.html

Tip it 90 degrees and the poles get great yarblockos of winter and summer as the equator perpetually freezes