Global warming

The Ghost In The Machine

yes the precession cause the change of seasons. in particular whether summer is when the earth is nearer or further from the sun. of course it's always opposite in the two hemispheres. at the moment the southern hemisphere has its summer closer to the sun. this ought to make southern seasons slightly more extreme, but the greater ocean area counteracts that.

the Milankovitch cycles are not the only natural influence on climate however.

not necessarily. I think the transitional phase is short, so the temperature variations over time are sort of like a square wave.

Also fairly recently, March 04, there was a hurricane named Catarina. The first recorder hurricane in the south Atlantic. A 1 in 100 year freak event, or a sign of global warming?

Global warming will increase the amount of energy in the atmosphere. this leads to more extreme weather events. But it's hard to tell them from normal freak events. For example a tornado hit Birmingham (UK) this year. But there was also a tornado in Birmingham in the first half of the 20th century.

-- Tom Wootten, Fresher NatSci, Trinity Hall. oof.trinhall.cam.ac.uk