More inconvenient truths

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.