400,000 years. Ice cores. As snow falls, bits of the atmosphere get trapped between the flakes and the little air bubbles are still there when it turns into a glacial layer. Drill an ice core, look at the little air bubbles. Here's Wiki: The ice forms layers, sort of like tree rings. In thes picture, also taken from Wiki, the arrows are the summer season and the darker areas the winter. http://en.wikipedia.org/wiki/Ice_core
Ottomaton, peace. We just disagree. I have always respected you personally.I must admit to seeing the world more than most through a poitical lens. Perhaps you aren't used to dealing with a hard core moderate leftist. Believe me. I have debated many a communist. In Houston I am surrounded by moderates and conservatives of various stripes. My close non-online friends tend to be almost all liberal.
