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Are you aware of the climate and antmosphere ever changing so abruptly according to ice core records?
by steve_adams_86 4y ago
Are you aware of the climate and antmosphere ever changing so abruptly according to ice core records?
- Retric 4y agoIce core records don’t go back that far. But some past mass extinction events were believed to be caused by more rapid climate swings resulting from asteroid impacts etc.
- steve_adams_86 4y agoThe thing about our situation is that no asteroid strikes or major geological events have occurred. So we know it’s possible to have major swings, but it’s less clear that they should occur without some obvious trigger.
- zosima 4y agoWhat resolution does ice core records have? Do they really show year-over-year change or are the core records being smoothed through natural processes?
- steve_adams_86 4y agoGreat questions, and I don’t have the answers. I’ll definitely look into it though.
- deleted 4y ago[deleted]
- joshuahedlund 4y agoI read a book about this once, forget the title. Greenland’s cores have clear annual layers for several thousands of years (validated by extra ash layers from known volcanic eruptions), and they can measure carbon and temperature from the isotopes trapped inside (temp is measured due to some effect of oxygen isotopes following a reliable temperature gradient or something like that, they had a couple independent measurement methods that matched up). At some point the compacted layers start to merge but they can still reliably estimate because the overall cyclic trends (on multi thousand year scales, due to mathematically regular wobbling of earth’s rotation and other factors) follow the same trends from the clearly annual layers. This goes back several hundred thousand years, with temp increases always following carbon increases. Edit: the book was The White Planet by Jean Jouzel, Claude Lorius, and Dominique Raynard