5 ms·

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

109 points by wglb 5mo ago

wglb 5mo ago
Paper in Proceedings of the National Academy of Sciences: https://www.pnas.org/doi/10.1073/pnas.2525919123 https://www.pnas.org/doi/10.1073/pnas.2525919123
dmix 5mo ago
TIL about silicate weathering https://en.wikipedia.org/wiki/Carbonate%E2%80%93silicate_cycle https://en.wikipedia.org/wiki/Carbonate%E2%80%93silicate_cyc... silicate rocks basically traps co2 over millions of years and causes temperatures to fall
- prawn 5mo ago
  There are various companies/projects set up around that idea: https://www.lithoscarbon.com/ https://www.lithoscarbon.com/ https://en.wikipedia.org/wiki/Carbfix https://en.wikipedia.org/wiki/Carbfix https://co2crc.com.au/ https://co2crc.com.au/ https://sgeas.unimelb.edu.au/research/carbon-trap-lab https://sgeas.unimelb.edu.au/research/carbon-trap-lab
  - fred_is_fred 5mo ago
    The Lithos Carbon idea is interesting. The mine they show looks like they can just scrape it rather than needing to mine it with explosives. Unfortunately the site's blog has 1 post and it is 3.5 years old. Is it still a going concern?
    - apothegm 5mo ago
      There’s an “in the news” entry on their site from this January (and a skim of the article does find them mentioned), so signs point to yes.
- chris_va 5mo ago
  It's really the alkalinity (e.g. the Mg++ or Ca++), which silicate rocks often have (but technically not limited to silicates). As an aside, we need to dissolve roughly one large mountain into the mix layer (top ~50m) of the ocean to have it fully take up atmospheric CO2. Without dissolving, the reaction is very slow (co2 in atmosphere => slightly lower pH rain => reaction with mostly passivated rock + erosion).
  - russearyus 5mo ago
    [dead]
chasil 5mo ago
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 https://en.wikipedia.org/wiki/Greenhouse_and_icehouse_Earth
- AlotOfReading 5mo ago
  We'll be much closer to a greenhouse earth than a glacial earth if we get that 4°C warming, so the distinction is more academic than practical in most contexts. What's a century here or there in geologic time?
  - timschmidt 5mo ago
    The Cambrian and Eocene reached around +14C compared to today[1]. Two of the warmest periods in Earth's history, granted. But life thrived. Governments, private property ownership, civilization, not as battle tested. 1: https://en.wikipedia.org/wiki/Geologic_temperature_record#/media/File:All_palaeotemps.svg https://en.wikipedia.org/wiki/Geologic_temperature_record#/m...
    - lukeify 5mo ago
      [dead]
    - reverius42 5mo ago
      Hmm. I do like civilization. How about humans, would human life thrive?
      - 5mo ago
jtwaleson 5mo ago
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.
- timschmidt 5mo ago
  Global cooling could be worse. But the danger from either comes from the speed with which it happens, and inflexible sociopolitical structures, more than the absolute difference in temperature. Rapid change doesn't permit gradual adaptation like relocation to more habitable areas. The danger from the current global warming trend comes from it's incredible rapidity compared to historical trends. Given time, humans and other animals will move toward the poles or toward the equator to find habitable zones. Put that on a rush schedule and everyone suffers.
  - arjunchint 5mo ago
    there are no guarantees in life, can look up any random day and see a meteor streaking across the sky and realize that this is the end regardless of "sociopolitical structures". All that matters is sociotechnological progress to be able to progress further enough to overcome these tests of existence.
    - timschmidt 5mo ago
      > look up any random day and see a meteor streaking across the sky That's happened rather more times in Earth's history than most folks are comfortable admitting. Tunguska would have leveled any major metropolitan city on the planet. I still think an impact is one of the more likely initiators of the Younger Dryas abrupt cooling and worldwide ~100M sealevel rise ~12,000 years ago. Conspicuously aligned with the oldest surviving traces of city living, agriculture, etc. It's increasingly accepted that a large portion of human history is 100M underwater on the continental shelves, estuaries, and other coastal areas where humans would have liked to live.
      - 5mo ago
amelius 5mo ago
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.
- layer8 5mo ago
  Enough bleach should do the trick. ;)
- cousinbryce 5mo ago
  Disco Ball Earth
SenHeng 5mo ago
There's an anime called Snowball Earth being aired right now. This article is not about that.
- layer8 5mo ago
  You don’t say.
  - SenHeng 5mo ago
    Not everyone reads TFA before coming in to the comments. The title is ambiguous enough and anime is something that a lot of nerds enjoy.
    - layer8 5mo ago
      I fail to see how one could conceivably think it’s about the anime, given the title. Nerds also know what “snowball earth” normally refers to.
metalman 5mo ago
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://www.ospo.noaa.gov/products/ocean/sst/contour/ https://nsidc.org/sea-ice-today https://nsidc.org/sea-ice-today https://climatereanalyzer.org/clim/seaice_daily/?nhsh=nh https://climatereanalyzer.org/clim/seaice_daily/?nhsh=nh
- lproven 5mo ago
  Short term (low single-digit decades): rapid sealevel rise. When (not "if") the Thwaites Glacier goes and the West Antartic Ice Sheet floats (not melts, just gets seawater underneath it) then we're looking at circa 5 metres, stabilising globally in about 12 days. Goodbye every single coastal city, air or sea port, industrial area, power plant, transport infrastructure in the world. Medium term (high single-digit decades): rapid global warming pushing the habitable zones to the poles and sub-polar regions. Note, critically, that means agriculture, as there are no established ecosystems to hunt/gather from at the poles. We are heading for ~7º C by the end of the 21st century. Never mind 4º, double it. Long term (millennia): another mass extinction event, much as the previous ones. We're 75-80% of the way through already, though. Geological terms... Hundreds of thousands of years: if humans go extinct, the planet will recover in 100K years or so, with plentiful but severely species-impoverished ecosystems. Tens of millions of years: lots of new species, new rich ecosystems form. Hundreds: if another sentient species evolves, it will have a hard time bootstrapping an technological civilisation, as we've extracted most of the the easy-to-access resources.
  - toasty228 5mo ago
Amorymeltzer 5mo ago
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.
- perrygeo 5mo ago
  Seconded. I learned a ton from it, as well as his previous book The Ends of the World on mass extinctions. His writing style is wonderful, he turns an academic subject into a page-turner. The Story of CO2 taught me something I had never considered. It wasn't exactly that photosynthetic life started pumping out O2 and chilled the planet. Snowball earth happened way later. It was photosynthetic life that got buried in sediment and locked it away from aerobic respiration. The amount of carbon stored in the earth's crust is insane. Fossil fuels are just a minuscule fraction of that. This has some implications for our current climate: If we want to use biology to sequester carbon (growing trees, algae, etc), it's only a temporary sink unless we lock it away for eons. Once it's eaten/burned, the CO2 is right back in the atmosphere. In short, we gotta physically put it back into the earth's crust if we want to draw down carbon.

109 points by wglb 5mo ago

wglb 5mo ago

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

dmix 5mo ago

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

prawn 5mo ago
There are various companies/projects set up around that idea: https://www.lithoscarbon.com/ https://www.lithoscarbon.com/ https://en.wikipedia.org/wiki/Carbfix https://en.wikipedia.org/wiki/Carbfix https://co2crc.com.au/ https://co2crc.com.au/ https://sgeas.unimelb.edu.au/research/carbon-trap-lab https://sgeas.unimelb.edu.au/research/carbon-trap-lab
- fred_is_fred 5mo ago
  The Lithos Carbon idea is interesting. The mine they show looks like they can just scrape it rather than needing to mine it with explosives. Unfortunately the site's blog has 1 post and it is 3.5 years old. Is it still a going concern?
  - apothegm 5mo ago
    There’s an “in the news” entry on their site from this January (and a skim of the article does find them mentioned), so signs point to yes.
chris_va 5mo ago
It's really the alkalinity (e.g. the Mg++ or Ca++), which silicate rocks often have (but technically not limited to silicates). As an aside, we need to dissolve roughly one large mountain into the mix layer (top ~50m) of the ocean to have it fully take up atmospheric CO2. Without dissolving, the reaction is very slow (co2 in atmosphere => slightly lower pH rain => reaction with mostly passivated rock + erosion).
- russearyus 5mo ago
  [dead]

chasil 5mo ago

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 https://en.wikipedia.org/wiki/Greenhouse_and_icehouse_Earth

AlotOfReading 5mo ago
We'll be much closer to a greenhouse earth than a glacial earth if we get that 4°C warming, so the distinction is more academic than practical in most contexts. What's a century here or there in geologic time?
- timschmidt 5mo ago
  The Cambrian and Eocene reached around +14C compared to today[1]. Two of the warmest periods in Earth's history, granted. But life thrived. Governments, private property ownership, civilization, not as battle tested. 1: https://en.wikipedia.org/wiki/Geologic_temperature_record#/media/File:All_palaeotemps.svg https://en.wikipedia.org/wiki/Geologic_temperature_record#/m...
  - lukeify 5mo ago
    [dead]
  - reverius42 5mo ago
    Hmm. I do like civilization. How about humans, would human life thrive?
    - 5mo ago

jtwaleson 5mo ago

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.

timschmidt 5mo ago
Global cooling could be worse. But the danger from either comes from the speed with which it happens, and inflexible sociopolitical structures, more than the absolute difference in temperature. Rapid change doesn't permit gradual adaptation like relocation to more habitable areas. The danger from the current global warming trend comes from it's incredible rapidity compared to historical trends. Given time, humans and other animals will move toward the poles or toward the equator to find habitable zones. Put that on a rush schedule and everyone suffers.
- arjunchint 5mo ago
  there are no guarantees in life, can look up any random day and see a meteor streaking across the sky and realize that this is the end regardless of "sociopolitical structures". All that matters is sociotechnological progress to be able to progress further enough to overcome these tests of existence.
  - timschmidt 5mo ago
    > look up any random day and see a meteor streaking across the sky That's happened rather more times in Earth's history than most folks are comfortable admitting. Tunguska would have leveled any major metropolitan city on the planet. I still think an impact is one of the more likely initiators of the Younger Dryas abrupt cooling and worldwide ~100M sealevel rise ~12,000 years ago. Conspicuously aligned with the oldest surviving traces of city living, agriculture, etc. It's increasingly accepted that a large portion of human history is 100M underwater on the continental shelves, estuaries, and other coastal areas where humans would have liked to live.
    - 5mo ago

amelius 5mo ago

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.

layer8 5mo ago
Enough bleach should do the trick. ;)
cousinbryce 5mo ago
Disco Ball Earth

SenHeng 5mo ago

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

layer8 5mo ago
You don’t say.
- SenHeng 5mo ago
  Not everyone reads TFA before coming in to the comments. The title is ambiguous enough and anime is something that a lot of nerds enjoy.
  - layer8 5mo ago
    I fail to see how one could conceivably think it’s about the anime, given the title. Nerds also know what “snowball earth” normally refers to.

metalman 5mo ago

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://www.ospo.noaa.gov/products/ocean/sst/contour/ https://nsidc.org/sea-ice-today https://nsidc.org/sea-ice-today https://climatereanalyzer.org/clim/seaice_daily/?nhsh=nh https://climatereanalyzer.org/clim/seaice_daily/?nhsh=nh

lproven 5mo ago
Short term (low single-digit decades): rapid sealevel rise. When (not "if") the Thwaites Glacier goes and the West Antartic Ice Sheet floats (not melts, just gets seawater underneath it) then we're looking at circa 5 metres, stabilising globally in about 12 days. Goodbye every single coastal city, air or sea port, industrial area, power plant, transport infrastructure in the world. Medium term (high single-digit decades): rapid global warming pushing the habitable zones to the poles and sub-polar regions. Note, critically, that means agriculture, as there are no established ecosystems to hunt/gather from at the poles. We are heading for ~7º C by the end of the 21st century. Never mind 4º, double it. Long term (millennia): another mass extinction event, much as the previous ones. We're 75-80% of the way through already, though. Geological terms... Hundreds of thousands of years: if humans go extinct, the planet will recover in 100K years or so, with plentiful but severely species-impoverished ecosystems. Tens of millions of years: lots of new species, new rich ecosystems form. Hundreds: if another sentient species evolves, it will have a hard time bootstrapping an technological civilisation, as we've extracted most of the the easy-to-access resources.
- toasty228 5mo ago

Amorymeltzer 5mo ago

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.

perrygeo 5mo ago
Seconded. I learned a ton from it, as well as his previous book The Ends of the World on mass extinctions. His writing style is wonderful, he turns an academic subject into a page-turner. The Story of CO2 taught me something I had never considered. It wasn't exactly that photosynthetic life started pumping out O2 and chilled the planet. Snowball earth happened way later. It was photosynthetic life that got buried in sediment and locked it away from aerobic respiration. The amount of carbon stored in the earth's crust is insane. Fossil fuels are just a minuscule fraction of that. This has some implications for our current climate: If we want to use biology to sequester carbon (growing trees, algae, etc), it's only a temporary sink unless we lock it away for eons. Once it's eaten/burned, the CO2 is right back in the atmosphere. In short, we gotta physically put it back into the earth's crust if we want to draw down carbon.