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Snowball Earth may hide a far stranger climate cycle than anyone expected

108 points by wglb

by chasil

3 subcomments

Most people do not know that we are in an icehouse phase, which is rare.
Earth spends most of its time in greenhouse phases.
"A "greenhouse Earth" is a period during which no continental glaciers exist anywhere on the planet... Earth has been in a greenhouse state for about 85% of its history.
"Earth is now in an icehouse state, and ice sheets are present in both poles simultaneously... Earth's current icehouse state is known as the Quaternary Ice Age and began approximately 2.58 million years ago... Earth is expected to continue to transition between glacial and interglacial periods until the cessation of the Quaternary Ice Age and will then enter another greenhouse state."
https://en.wikipedia.org/wiki/Greenhouse_and_icehouse_Earth

by Amorymeltzer

1 subcomments

I hugely recommend reading Peter Brannen's The Story of CO2 Is the Story of Everything. I picked it up thinking it'd be a good book about climate change—it is—but it's so much more. It's an excellent journey through our planet's (bio)geochemistry, and really gives you a sense for the power and scope of CO2 over millions and billions of years. Snowball earth features prominently, and there are some really fascinating history and consequences of them.

by wglb

0 subcomment

Paper in Proceedings of the National Academy of Sciences: https://www.pnas.org/doi/10.1073/pnas.2525919123

by dmix

2 subcomments

TIL about silicate weathering https://en.wikipedia.org/wiki/Carbonate%E2%80%93silicate_cyc...
silicate rocks basically traps co2 over millions of years and causes temperatures to fall

by amelius

2 subcomments

If only we could get the albedo to such value that we get a self-sustaining cycle of lower temperatures. Maybe if we turned that great pacific garbage patch into a great pacific mirror patch.

by jtwaleson

2 subcomments

Just as a thought experiment, what would be worse for humanity. Global warming or global cooling by the same amount of degrees C?
I'm in western Europe and really hope the AMOC will not collapse.

by SenHeng

1 subcomments

There's an anime called Snowball Earth being aired right now.
This article is not about that.

by metalman

1 subcomments

Having followed every bit of info, data, and discussion(that I can find) on climate, geology, etc, since I was a child in the 1970's, I can point to the fact that earth climate science is ferociously complex, but that almost all of the variables are pushing towards a much warmer planet, and that there is NO big offset. Like it or lump it, we have whatever passes for a global civilisation, where we are so intertwined that we cut special "deals" with the people we are bombing and bieng bombed by, for certain trade items, ie: gasses for chip production, "humantarian exemptions", etfuckingcetera, and so the real threat to All That™, is ocean rise, as it can wipe out shipping fast under some realistic scenarios , which if fact, are playing out there preliminary set points.
https://www.ospo.noaa.gov/products/ocean/sst/contour/
https://nsidc.org/sea-ice-today
https://climatereanalyzer.org/clim/seaice_daily/?nhsh=nh