Environment & Energy

Last edited Mon Jan 9, 2012, 10:22 AM - Edit history (2)

This first shows the linkage between temperatures and greenhouse gases (note that the X-axis measures time before the present, moving right takes you further into the past):
http://www.victoria.ac.nz/antarctic/research/research-prog/anzice/default.aspx

[font size=3 face=Times,Times New Roman,Serif]A record of greenhouse gases [carbon dioxide, methane] for the past 400,000 years as preserved in the Vostok Ice Core from Antarctica. The record shows ice ages when average temperatures were 6 - 8°C cooler than now. Such periods were punctuated by warm phases such as Stage 5e (red arrow) when temperatures were around 2°C warmer than today’s average. ANZICE will focus on those warm phases as case studies for what to expect in the future.[/font]

This next shows the linkage between glaciation and Milankovitch cycles (note that the X-axis measures time before the present, moving right takes you further into the past):
http://www.globalwarmingart.com/wiki/File:Milankovitch_Variations_png

The natural pattern appears to be relatively rapid warming (c. 10,000 years) initiated by Milankovitch cycles, and amplified by feedbacks (e.g. GHG’s, albedo) followed by much slower cooling (c. 100,000 years) note, moving right takes you forward in time:

http://www.globalwarmingart.com/wiki/File:deglaciation_png