Daily Archives: January 16, 2009

Global Warming, the Blog Epic ~ 06 ~ A Glacial Cycle

This is the sixth in a series of reposts from gregladen.com on global warming.

i-e1372cd57ce206dff3631a4a9438e737-epic-GlobalWarming.jpgIn the last post in this series I talked about two aspects of large scale climate change: Milankovitch orbital geometry and the cycles of glaciation this effect causes, and the role of plate tectonics and related changes in altering sea and air currents, which in turn determine a great deal about climate change as well.

Now I want to have a quick look at a single glacial cycle (the most recent one of many), and one way in which the cycle is observed in the ancient record, identified, measured, and described.

As discussed earlier, we know that glaciations (glacial cycles, or “ice ages”) involve the formation of large continental glaciers, which are in turn made of accumulated precipitation (snow), most of which ultimately comes from the oceans via evaporation. So as water is transferred from the oceans to the land-based glaciers, the glaciers build up and sea level goes down.

Since water can be made of either lighter or heavier isotopes of oxygen, and the lighter-isotope water evaporates more easily, the glaciers are isotropically light. This means, in turn, that the oceans are isotropically heavy. This isotopic bias is preserved in the hard parts of marine organisms that use oxygen from sea water as part of their growth process.
Continue reading Global Warming, the Blog Epic ~ 06 ~ A Glacial Cycle

Live Blogging the NC ScienceOnline 09 Conference

I’m in. In North Carolina, that is. Nothing happening yet. It is about 100 degrees warmer here than it was when I woke up this am. Flew with Stephanie Zvan (Almost Diamonds) and Ben Zvan (who is here to do a photo shoot). Checking out room, internet, preparing to go get a bite to eat and/or a beer or something.


OK, back from having beers and dinner and beers. Grrl Scientist seemed to be live blogging from the restaurant . I got to meet my blogging Idol, Bora, and we chatted for some time. And I gotta tell you, I will never get enough of this wonderful southern accent!!!!

In other business, advances were made at dinner on our new blogging project, about which I will not say a word even if tortured. You’ll see.

Oh, I also got to meet the Blogg Herders, and they are as totally cool in real life as they appear to be in email, which is the only place I’ve ever seen them before.

BTW as far as we know none of the bloggers coming here were on the plane that crashed in NY, as far as we know.

OK, just had breadkfast, sitting in the lobby with the one and only Blake Stacey and Almost Diamonds blogger Stephanie Zvan. We are expecting Lou to come by in a few minutes, to conduct some business that I think is not my place to mention.

Blake is regaling us with stories of cyclotrons and stuff.

Lou is late, and I’m going to get some lunch now.

Had lunch, now blogging. Pizza and beer with Erin and Arikia at 3:00. I for one look forward to pizza with our Scienceblogs overlords.

I’ll keep you posted.

Global Warming, the Blog Epic ~ 05 ~ Causes of Large Scale Change

This is the fifth in a series of reposts from gregladen.com on global warming.

i-e1372cd57ce206dff3631a4a9438e737-epic-GlobalWarming.jpgDuring the 1970s and 80s, creationists had a long list of reasons to doubt evolution, and every one of those reasons was wrong. But they had so many reasons, and it was so hard to keep track of them all, each with various versions, that a creationist that was trying to not live a lie could convince themselves that they had an honest dispute with evolutionary biology. But if you sat down and looked at every detail, “creation science” could be shown to be nothing more than a big bag of falsehoods. So to continue to be a creationist you had to be willing to live that lie.

Then intelligent design creationism came along. IDC does not require that you have a long list of lies. Instead, you have one single great big lie that can’t be disproved (and is utterly unrelated to science, and in fact, can’t be proven, either).
Continue reading Global Warming, the Blog Epic ~ 05 ~ Causes of Large Scale Change