[HN Gopher] Possibility for strong high-latitude cooling under n...
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       Possibility for strong high-latitude cooling under negative
       emissions
        
       Author : rgrieselhuber
       Score  : 68 points
       Date   : 2022-03-06 16:24 UTC (6 hours ago)
        
 (HTM) web link (www.nature.com)
 (TXT) w3m dump (www.nature.com)
        
       | mrfusion wrote:
       | Sorry but I'm all panicked out.
        
       | freddealmeida wrote:
       | Quite interesting that this is being published in Nature. I think
       | there are far worse things that need to be removed. But so little
       | is discussed on the affect of the sun moving into a solar
       | minimum. That will have some serious consequences as well.
        
         | SantalBlush wrote:
         | >That will have some serious consequences as well.
         | 
         | According to NASA [1], that is false.
         | 
         | [1] https://climate.nasa.gov/ask-nasa-climate/2953/there-is-
         | no-i...
        
           | hedora wrote:
           | This particular issue has been well understood for at least
           | 30 years. Greenhouse gasses are a first order effect. Solar
           | cycles are second order.
        
             | wrycoder wrote:
             | The principal greenhouse gas is water vapor, and the effect
             | of solar variation on that is not at all "well understood".
        
       | whiddershins wrote:
       | It is so easy to not pay attention to how bad global cooling,
       | and/or co2 reduction curtailing plant growth, could be for the
       | environment and for humans.
       | 
       | Global warming and CO2 rise are such difficult problems, and we
       | put so much focus there, it makes me really glad to see some
       | people taking a broad view.
        
       | hedora wrote:
       | Tl;dr: Climate change is likely to shut down the Atlantic
       | currents, covering Europe and the US northeast in a glacier.
       | 
       | (I saw a PBS special on this part in the 90's. Recent satellite
       | data strongly suggest this is already happening. The last time
       | this happened, Europe went from "too hot" to "glacier" in the
       | under fifty years.
       | 
       | If we wait for that to happen, then cool the atmosphere, then
       | it'll make the coming ice age worse in the short term.
       | 
       | In other decades-old news, if we don't start capturing CO2 after
       | that, and the predictions about runaway greenhouse gas mechanisms
       | are true, Earth will become like Venus, obliterating life on
       | earth.
       | 
       | Am I the only one that learned about this from watching PBS in
       | the 90s? Is there something novel in the paper? It's good to
       | raise awareness of just how f-cked we are, I guess.
        
         | ripper1138 wrote:
         | So you feel confident that Europe will be under a glacier in 50
         | years?
        
           | Imnimo wrote:
           | I think you've misunderstood the claim - they're saying that
           | once the currents shut down, it would take 50 years for
           | glaciers to form. But the currents are obviously still
           | flowing today, and my understanding is that a collapse is
           | projected to take many decades.
        
           | hedora wrote:
           | I'm confident we'll get about 50 years warning when/if the
           | current stops. It's currently weakening, and weather is a
           | chaotic system.
           | 
           | I'm also confident that the root cause of the crunching noise
           | and vibrations from the front end of my car will eventually
           | lead to a breakdown, but I don't have any idea if it'll
           | happen tomorrow or in a year.
        
             | ripper1138 wrote:
             | I see. Of course the North Atlantic current will
             | change/stop at some point regardless of any actions we take
             | (assuming we don't have technology to keep it going
             | somehow). But delaying that as long as possible is a noble
             | goal.
        
         | peteradio wrote:
         | One things for sure, the children born today will be
         | genetically optimistic.
        
         | sacrosancty wrote:
         | Not a great idea to expect to learn about the world from
         | sensationalist TV. Especially not such an immature field as
         | climate science in the 90's.
        
           | hedora wrote:
           | You do realize I mean the 1990's right? The show was
           | broadcast in color, so it came after climate change science
           | had "matured".
           | 
           | Concretely, the magnitude of our current predicament was
           | correctly forecast by computer models well before 1980, and
           | the basic mechanisms and effects those models were based on
           | were well-established by the 1960s.
           | 
           | Claims to the contrary have been extensively documented to be
           | part of a paid misinformation campaign the fossil fuel
           | industry ramped up in the early 1980s.
           | 
           | The show wasn't particularly sensationalist, for what its
           | worth. Climate change was a bipartisan concern back then, and
           | it mostly focused on the fossil records that backed up the
           | claims it made. It also talked about the solar cycle's impact
           | on earth's average temperature and compared the magnitude of
           | the effects over time.
           | 
           | All the technology that was needed to head off disaster was
           | already commercialized, assuming a one-two punch, where phase
           | two involved better batteries.
           | 
           | No one imagined we would choose to take no action for another
           | 30 years.
        
             | hedora wrote:
             | To get an idea of the optimism, Biff from Back to the
             | Future was based on Trump and ends up waxing an engineer's
             | car.
             | 
             | If I had to bet what actor would be president in 2016, I'd
             | have guessed Patrick Stewart, and that his second move
             | (after installing the captain's chair in the oval office)
             | would be pointing at a clean energy plan to replace our
             | carbon nuclear fission power grid with fusion / solar and
             | saying "make it so".
        
         | randomsilence wrote:
         | All that freed, formerly captured carbon comes from trees and
         | plankton. How could burning it all lead to life-destroying
         | conditions when life must have been able to exist under those
         | conditions?
        
           | mostly_harmless wrote:
           | "all that kenetic energy released when jumping off a building
           | was formerly potential energy stored when walking up the
           | stairs. How can that lead to life destroying conditions when
           | life previously held that energy?"
           | 
           | The rapid change in environments can make many species no
           | longer suitable for their environment leading to extinction.
           | Sometimes they can transfer to a new environment, or sustain
           | at a degraded efficiency, but often they cannot if the
           | environment change is drastic enough. This is happening
           | everywhere all at once.
        
             | marcosdumay wrote:
             | The GP isn't talking about species extinction.
        
           | ceejayoz wrote:
           | Same reason breaching a big dam does more damage than the
           | same volume of water in an undammed river.
        
           | Retric wrote:
           | People aren't going to destroy all life on earth via climate
           | change because humans are going to be dead in conditions that
           | many life forms would happily survive in. Having said that,
           | evolution operates on geologic timescales 100 years isn't
           | nearly enough time for most species to adapt to significantly
           | different conditions. Florida alligators might happily expand
           | their range further north in response to climate change, but
           | that's different.
           | 
           | As to the larger point, the sun was ~30% dimmer 4.5 billion
           | years ago and will get about 67% brighter over the next 4.7
           | billion years. While we would be dead long before we could
           | free up all the worlds trapped carbon, in such a hypothetical
           | situation the world isn't simply returning to an earlier
           | state.
        
           | tsimionescu wrote:
           | Energy on Earth isn't conserved, as it's not an isolated
           | system - the Sun is constantly adding energy to the Earth,
           | and we are constantly radiating energy out into space as
           | well. Coal and oil were basically batteries filled with solar
           | energy from millions of years ago. We are now discharging
           | those batteries, adding back all of the solar energy captured
           | over millions of years to the Earth today, in addition to all
           | of the energy the Sun is still adding at more or less the
           | same rate.
           | 
           | It's the same principle as what makes a battery fire so
           | destructive - all of the energy stored in the battery in a
           | plant somewhere else suddenly gets discharged all at once in
           | your car.
        
           | 41b696ef1113 wrote:
           | You are releasing 1e6 to 1e7 years of energy in the space of
           | 1e2.
        
         | twofornone wrote:
         | Glaciers increase albedo. I suspect there are numerous
         | understated/undiscovered feedback mechanisms which will
         | actually result in cooling as the climate changes and keep the
         | global temperature livable.
        
           | wrycoder wrote:
           | Not a feedback, but a reduction in polar soot due to China
           | moving away from dirty coal emissions to nuclear power could
           | also increase albedo.
        
         | BurningFrog wrote:
         | The IPCC reports don't predict anywhere near these disasters,
         | even in their worst scenarios.
         | 
         | I'll trust those over a PBS special from the 1900s.
        
       | sgt101 wrote:
       | In other news: population crisis on Mars.
        
       | detritus wrote:
       | We seem to be so far from a practically-useful level of CO2
       | removal that this seems like a shrill level of concern. That
       | said, the logic could apply to much quicker solutions that could
       | be distributed globally, such as atmospheric albedo modification
       | or space based solar barriers (the latter being hugely
       | speculative, of course - but I could imagine a few SpaceX
       | starships put to poorly-considered use being able to muster
       | something in a decade or three).
        
         | go_elmo wrote:
         | Approaches aiming at increasing ocean bio activity, thus carbon
         | capture by providing "ocean desert zones" with nutrients by
         | whirling up ocean floor in those regions seems interesting for
         | that purpose. Still a huge inception into the bio system thus
         | risky.
        
           | detritus wrote:
           | Ah yes, I'd forgotten about iron-seeding - I was thinking
           | entirely in terms of industrial solutions.
        
             | galangalalgol wrote:
             | I still think iron fertilization is the best bet, not for
             | co2 removal, but for albedo modification. Keeping
             | equatorial kelp or algae mats alive would prevent lots of
             | energy from entering the system. Those mats have albedo
             | close to snow in the infrared, where water is about as
             | absorptive as it gets.
        
               | detritus wrote:
               | I wonder if we could somehow use strategic placement of
               | fertilisation to encourage processes that laterally help
               | in cleaning up (/collecting) plastic pollution in oceanic
               | gyres?
               | 
               | A girl can dream.
               | 
               | - ed: I am fascinated by the idea that otherwise horrid
               | floating plastic pollution can act as centres for bio-
               | accumlation leading to local, floating bio-domains. I
               | guess the real problem is plastic bags and fishing nets,
               | not toothbrushes that happen to float.
        
             | go_elmo wrote:
             | Ive seen stunning simple / passive water column chimney-
             | effect approaches to do this using lower water levels
             | mixing, no sources though, was german tv (arte station)
        
         | ttiurani wrote:
         | This is an important study because most (all?) scenarios used
         | by the IPCC depend heavily on these (as of now) wildly
         | optimistic CO2 removal levels, either with BECCS or DACs.
         | 
         | In order to hit the "brief and rapidly closing window" we have
         | for effective action, we need to look into lowering material
         | flows and energy use by targeting overconsumption. We simply
         | don't have time to wait for a tech miracle, and - as this study
         | points out - the miracle can have huge downsides.
        
           | s1artibartfast wrote:
           | Unless CO2 removal is profitable without subsidies, it's
           | pointless and the money should go into Renewables. If you can
           | cut emissions, the CO2 takes care of itself quickly from
           | natural sinks.
           | 
           | Per the ipcc model, if we could wave a magic wand and have
           | zero emissions tomorrow, CO2 levels would fall faster than
           | they have been increasing.
           | 
           | We already have free CO2 removal. The challenge is and always
           | has been on the emission side.
           | 
           | CO2 levels are about 420 ppm and go up about 1.5 per year. A
           | 120 year half life yields -3.5 ppm per year.
           | 
           | It is worth investing some money in development for the
           | moonshot possibility of economic viability. Unless it becomes
           | cheaper to capture than build renewables, the the money will
           | always be better spent on green energy.
        
             | photochemsyn wrote:
             | "Per the ipcc model, if we could wave a magic wand and have
             | zero emissions tomorrow, CO2 levels would fall faster than
             | they have been increasing."
             | 
             | Traditionally, the idea is that the ocean would absorb the
             | 'excess' CO2 put there by fossil fuel combustion over the
             | industrial era. However, this is quite a slow process and
             | it's entirely possible to reach a new steady state of
             | relatively high atmospheric CO2 (and high global
             | temperature, i.e. ice-free poles) and stay there for
             | several million years - it's happened in the past.
             | Furthermore, we have the permafrost melt ongoing across the
             | Arctic, and shallow marine sediments are also releasing
             | methane and CO2. This will continue for decades in the
             | immediate zero-emission scenario, that turning point has
             | come and gone.
             | 
             | Maybe if a full transition off fossil fuels had begun in
             | 1980, when the science was clear, we'd be stabilizing at
             | current conditions (*it takes ~100 years for the climate
             | system to finish responding to current forcing, assuming no
             | additional forcing, mainly due to oceanic warming lag
             | effects). We're in for warming for the next 50 years, no
             | matter what, and the world is clearly not getting off
             | fossil fuels any time soon, all the major fossil fuel
             | actors have plans for status quo production for the next 30
             | years (rather than say 3% reduction per year, which would
             | mean no fossil fuel production in 30 years).
             | 
             | It's going to happen slowly on human time scales, i.e. the
             | scale is decadal for noticeable differences in the year-to-
             | year average, but it's also inexorable. "It's in the post"
             | is the British saying that applies. Like trying to throw
             | the rudder over on the Titanic after the iceberg is
             | detected, it's all too little too late.
        
             | gonzo41 wrote:
             | The profit / reward is your kids get to live and have kids.
        
           | hannob wrote:
           | I have no idea why this comment got downvoted. It points
           | precisely to the point: Many current climate scenarios have
           | already negative emissions "priced in". We absolutely need to
           | have research to better understand what that means, and we
           | should have a plan b if negative emissions at large scales
           | don't work.
        
             | landemva wrote:
             | I didn't downvote though I noticed this, 'We simply don't
             | have time to wait ...'.
             | 
             | Whatever the topic, I mentally ignore posts which shill the
             | NEXT WORST THING EVER.
        
         | convolvatron wrote:
         | I think a more important lesson here is that this is not a
         | simple system. its pretty unlikely that we're going to able to
         | calmly walk it back to the state it was in before
        
           | landemva wrote:
           | There were many prior states. In fact, it changes. Vikings
           | had pastures on Greenland until it got cold and they were
           | driven off. Greenland is now covered in snow and ice. Will
           | Greenland return to pastures? Probably at some time.
        
           | RC_ITR wrote:
           | The even more wild concept is that the atmosphere's
           | composition was already changing before human involvement, we
           | just sped up the process by like 1000x.
           | 
           | We don't normatively need the atmosphere to be "natural," we
           | just need it to be in a state that doesn't destroy the
           | thousands of years of infrastructure we've built.
        
       | 01100011 wrote:
       | What if we tap sources of energy, like fusion and to some
       | extent(*) fission, which are novel to the normal solar/earth
       | system and release extra heat energy into the atmosphere? Since
       | this study is obviously only relevant in the far future, why not
       | add in likely future technologies to the mix?
       | 
       | It seems to me that at some point we could just wrap the earth in
       | shutters(since we're talking far future anyway) or intentionally
       | release greenhouse gasses to servo the planet's temp.
       | 
       | * - I believe much of the geothermal heat is actually heat from
       | fission already so I don't know if fission energy changes the
       | balance much.
        
         | throwanem wrote:
         | > I believe much of the geothermal heat is actually heat from
         | fission already
         | 
         | On what basis do you believe this?
        
           | topaz0 wrote:
           | This seems to have a good explainer:
           | 
           | https://www.psu.edu/news/research/story/probing-question-
           | wha...
        
       | no-body wrote:
       | But aren't we at the end off the small ice age? And is global
       | warming really something we can prevent, or is it part off the
       | normal warming and cooling cycles off the earth? I sometimes
       | wonder if all the effort we do is in vain.
        
         | mostly_harmless wrote:
         | There's a huge difference between warming over a couple tens of
         | thousands of years (natural rate), and warming over a couple of
         | decades (our current trajectory).
         | 
         | That difference is the eradication of much of life on earth
         | that is unable to evolve to a new environment. For example,
         | insect numbers worldwide are drastically lower than decades
         | ago, and insects are required for almost all pollination of
         | plants and a key source of food for small animals. The "food
         | chain" collapses if there is no first chain.
         | 
         | Even a partial loss of ecodiversity can lead to further
         | problems later.
         | 
         | Our efforts are certainly not in vain.
        
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