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Earth Science

Ending Greenhouse Gas Emissions May Not Stop Global Warming, Study Says (phys.org) 303

An anonymous reader quotes a report from Phys.Org : Even if humanity stopped emitting greenhouse gases tomorrow, Earth will warm for centuries to come and oceans will rise by meters, according to a controversial modeling study published Thursday. Natural drivers of global warming -- more heat-trapping clouds, thawing permafrost, and shrinking sea ice -- already set in motion by carbon pollution will take on their own momentum, researchers from Norway reported in the Nature journal Scientific Reports. Using a stripped-down climate model, [lead author Jorgen Randers, a professor emeritus of climate strategy at the BI Norwegian Business School] and colleague Ulrich Goluke projected changes out to the year 2500 under two scenarios: the instant cessation of emissions, and the gradual reduction of planet warming gases to zero by 2100.

In an imaginary world where carbon pollution stops with a flip of the switch, the planet warms over the next 50 years to about 2.3 degrees Celsius above pre-industrial levels -- roughly half-a-degree above the target set in the 2015 Paris Agreement -- and cools slightly after that. Earth's surface today is 1.2C hotter than it was in the mid-19th century, when temperatures began to rise. But starting in 2150, the model has the planet beginning to gradually warm again, with average temperatures climbing another degree over the following 350 years, and sea levels going up by at least three meters. Under the second scenario, Earth heats up to levels that would tear at the fabric of civilization far more quickly, but ends up at roughly the same point by 2500.

The core finding -- contested by leading climate scientists -- is that several thresholds, or "tipping points", in Earth's climate system have already been crossed, triggering a self-perpetuating process of warming, as has happened millions of years in the past. One of these drivers is the rapid retreat of sea ice in the Arctic. [...] Another source is the thawing of permafrost, which holds twice as much carbon as there is in the atmosphere. The third is increasing amounts of water vapor, which also has a warming effect. Reactions from half-a-dozen leading climate scientists to the study -- which the authors acknowledge is schematic -- varied sharply, with some saying the findings merit follow-up research, and others rejecting it out of hand.
There is a way to stop the melting process, but it involves sucking CO2 out of the atmosphere and storing it underground, which isn't yet possible at the scale required. The authors also suggest making Earth's surface brighter and planting billions of trees to slow or halt the planet warming gases.
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Ending Greenhouse Gas Emissions May Not Stop Global Warming, Study Says

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  • by Gravis Zero ( 934156 ) on Thursday November 12, 2020 @10:49PM (#60718346)

    Since apparently we've already created a positive feedback loop for releasing CO2, going "carbon neutral" is no longer an option. What we need to do now is actually start removing CO2 from the sky and oceans. It gets worse because the only way to shut down this feedback loop is to actually remove it faster than it's being released. This will require thousands if not millions of sites to accomplish this. The best way would be to proliferate nuclear energy and use every spare watt to capture and convert CO2 into carbon (which we've made huge progress on).

    Frankly, this is a far larger threat than any military foe, so if the US actually gave a damn about defense they would be using their military budget for geoengineering.

    • Well, they are taking it seriously [theguardian.com].

    • by Mal-2 ( 675116 )

      Turning CO2 into limestone, which then can be broken into sand to replace the dwindling supply of sand used to make concrete, solves two problems with one process -- assuming a plethora of free energy to run it.

      • I've seen a number of news articles, white papers, and so on about people working on using basalt in cement as a carbon sink.

        Basalt is a common mineral consisting of oxides of calcium, magnesium, silicon, and other metals. It's the calcium oxide, or lime, that is of most interest. Most common cements use a mix of what is mostly lime and sand with enough water to turn it to a flowing liquid. As it cures and hardens the lime reacts with CO2 in the air to become limestone. The longer cement cures the harde

    • Comment removed based on user account deletion
      • No, the best way is to plant a fuck ton of trees and irrigate them.

        Trees are carbon neutral. You need to learn about the life-cycle of trees.

        • They use CO2 when growing though. So, cut down all old trees, bury them or make paper or whatever (other than burning) and plant young trees. Once they slow down growing, cut them down and replace them. And so on.

          • Doing so requires significantly more energy, time and effort than carbon capture. It will also deplete the soil if you repeat the process often enough.

    • Environmentalists don't want nuclear either.

      • by blindseer ( 891256 ) <blindseer@eartBO ... minus physicist> on Friday November 13, 2020 @01:44AM (#60718672)

        Environmentalists don't want nuclear either.

        This is changing.

        We spent something like 40 years with few to no new nuclear power reactors in the USA. This has left us with a fleet of nuclear power plants that will be reaching the end of their operational life in rather rapid succession. A nuclear power plant near me just shutdown for the last time, they don't plan to refuel and restart it.

        What is going to replace these low CO2 emission power sources on the grid? Windmills? Solar? They can't even keep up with growth in demand as it is. If there's going to be potentially dozens of nuclear power reactors shutting down every year, each producing nearly a gigawatt of electricity, then that leaves a gaping hole in our electrical generation capacity.

        We will be replacing these old nuclear fission reactors with new nuclear fission reactors or natural gas. That's because the third option is the lights going out.

        Environmentalist might like the idea of no more nuclear power but they like the idea of being able to recharge their iPhones more.

    • I don't see why certain corporations who have profited so wildly on GMO crops can't be tasked to develop a GMO plant that can grow anywhere quickly and suck up more CO2 than anything else. A variant of seaweed would be good too since I understand that the oceans are becoming acidified due to absorption of CO2. Purely mechanized ways of scrubbing CO2 out of the air sounds like the long way around.
    • by blindseer ( 891256 ) <blindseer@eartBO ... minus physicist> on Friday November 13, 2020 @01:04AM (#60718616)

      Frankly, this is a far larger threat than any military foe, so if the US actually gave a damn about defense they would be using their military budget for geoengineering.

      Use the military budget for geoengineering? That's going to go well. (That's sarcasm by the way.) There are nations in this world that would conceivably see global warming as beneficial. Russia for example has been waging wars to get a warm water port, a port that doesn't freeze over every winter. They've been looking to drill for oil and gas in the Arctic Circle for as long as there has been a Russia, but the ice slows them down. Large regions of Russia could be turned to arable land if the world was a bit warmer.

      That's just one nation with enough firepower to give the USA a very bad day if they thought we were waging a geoengineering war on them. China, North Korea, and likely a few other nations might join in on that fight. Perhaps not because they see geoengineering as a threat but because they don't like the idea of a democratic nation making their socialism look bad.

      That said, we do see the military putting considerable funds in lowering their reliance on fossil fuels. There's certainly a part of the military that sees global warming as a threat to national security. There's also a part of the military that sees any reliance on foreign sourced fuel needed for tanks, jets, and ships as a national security threat. This has lead the various military branches to search for alternatives to petroleum.

      The USAF has been experimenting with biomass fuels for their jets. There's been successful tests with a mix of petroleum and soybean oil in tankers and transports. I read that they planned to test this fuel on fighter jets, I don't know if that happened or what the results of that was.

      The US Navy has been developing a method to synthesize jet fuel at sea using energy from nuclear power on a ship and raw material out of the ocean. This is a well known chemistry of "cooking up" hydrocarbons but it has to be shown viable for placement on a ship. This means small enough, light enough, efficient enough, low enough in cost, high enough in reliability, and can take at least a moderate beating from being out at sea on a warship.

      The US Army has been working on solar panels that can roll up like a tent, and perhaps be integrated into the tent. Windmills that can be erected on remote outposts. As well as the potential for small nuclear reactors that are small and light enough to move by a train or large truck.

      The US Coast Guard has been begging for nuclear powered icebreakers, and they might just get them soon. The US Navy has asked for nuclear powered surface ships besides carriers for a very long time, but Democrats in Congress have prevented that from happening since the last nuclear powered cruisers were retired in the 1990s. If the ships aren't powered by low CO2 nuclear fission reactors then they will most likely burn petroleum. If it's not petroleum then it could be synthesized hydrocarbons, biomass fuel, or some mix of them, but that means there needs to be a reliable energy source to produce and process these fuels. Something that can be secured from a bombing run, not left out in the sun, wind, and rain. What might that be?

    • Since apparently we've already created a positive feedback loop for releasing CO2, going "carbon neutral" is no longer an option. What we need to do now is actually start removing CO2 from the sky and oceans.

      This is the hypothesis supported by the current study.

    • by gweihir ( 88907 )

      Indeed. But it is seriously doubtful that the human race can do this on the scale required, even if global peace and understanding breaks out tomorrow and everybody contributes the max they can.

    • "Frankly, this is a far larger threat than any military foe, so if the US actually gave a damn about defense they would be using their military budget for geoengineering."

      Our entire military budget is about $0.7T. Social Security and Medicare are around $1.0T and $1.2T. Why not nuke both those programs and use that money. It would kill a lot of folks that depend on those things, but using the defense budget would kill the country when Andorra invades. (No, wait, 450 million guns in civilian hands would

  • by cowdung ( 702933 ) on Thursday November 12, 2020 @10:57PM (#60718370)

    An often forgotten cause of global warming isn't merely emissions but the fact that we continue to use land-heavy agriculture to produce our food.

    We need to invest in systems that reduce the amount of land needed to cultivate our food and give back land to giant nature reserves full of trees.

    The main cause of environmental destruction is agriculture. We need it to change so that deforestation and habitat destruction is no longer a thing.

    The carbon sequestration comes naturally with millions and millions of giant trees all over the world.

    • Heavy farming reduces land use. Forests are making a natural comeback in Europe and North America, as farms are abandoned. https://ec.europa.eu/jrc/en/pu... [europa.eu] Obviously, committed scare mongerers do not want to hear the truth.
    • by ghoul ( 157158 )
      Instead of lecturing Brazil and Indonesia about not using land for farming, US should set an example. A rich country does not need to grow food; it can import from poorer countries. Flyover country states should be abolished and amalgamated into one large territory (Puerto Rico status) and used for afforestation. The population can be shifted to the coasts or work as forest guards. Bonus points for having a permanent Democrat majority in the Senate.
      • Sure, sure. We'll just be beholden to every other country of the world for our very existence. Oh by the way that just offloads the land use on everyone else, and we'd have no control over what methods they use, and knowing most countries that we'd end up buying food from they'd wreck the land even worse than we have. Total non-starter.
      • by blindseer ( 891256 ) <blindseer@eartBO ... minus physicist> on Friday November 13, 2020 @01:25AM (#60718642)

        Instead of lecturing Brazil and Indonesia about not using land for farming, US should set an example. A rich country does not need to grow food; it can import from poorer countries.

        That's a great idea, except not really.

        The USA should not hand over it's ability to feed itself to volatile third world nations. As it is now many nations of the world rely on American exports to feed themselves.

        If these poorer countries want to export food to the USA then they first need to be able to feed themselves. To do that will take a stable government, modern farming techniques, and generally replicating what the USA is doing. If they do that then they won't be "poorer countries" any more. Then what? Are they supposed to hand over their ability to feed themselves to some other nation poorer than them? Much of the wealth in the USA comes from not having to export this wealth for food. Our agricultural abundance keeps the world from starving.

        The USA relied on imports for vital resources before, and it was used against us. Why set ourselves up to be threatened with starvation like the oil crises of the 1970s?

        We are seeing European nations set themselves up for failure by relying on Russian natural gas. This will be used against them once Russia is convinced that Europe is sufficiently addicted to their energy. After that it will be one natural gas shortage after another until Europe collapses or learns to break this addiction.

        The USA isn't going to hand over it's independence, and wealth, in an attempt to prop up nations that can't keep their act together.

        • 3rd world countries do not exist anymore since the early 1980s.
          Only countries with defunct government, like Somalia, or South Sudan, can not feed themselves.

      • by sfcat ( 872532 )

        Instead of lecturing Brazil and Indonesia about not using land for farming, US should set an example. A rich country does not need to grow food; it can import from poorer countries. Flyover country states should be abolished and amalgamated into one large territory (Puerto Rico status) and used for afforestation. The population can be shifted to the coasts or work as forest guards. Bonus points for having a permanent Democrat majority in the Senate.

        People like you are why Republicans win there so easily. Its a grand idea which sounds good but is poorly thought out, probably won't work and the brunt of the negative consequences will be felt by the poor (them). You truly live up to your name.

    • True - and animal agriculture is several factors higher than plants. Over 40% the land used in the US is for animal agriculture. Global breakdown can be found here: https://ourworldindata.org/agr... [ourworldindata.org]

    • by Misagon ( 1135 )

      It isn't just that a lot of land is being used for agriculture, the methods used for agriculture also matter.
      Traditional ploughing releases greenhouse gases from the fertiliser in the soil.
      Animal dung has to be processed to capture the emissions from it.

      And of course, we need to stop eating so much meat. We should not omit it entirely from our diet, just stop eating more meat than humans have ever done before. This meat consumption is also giving more people heart disease.

    • Mankind is throwing away 50% - 50% of all food produced.

      I doubt the size of agricultural areas has a significant impact on CO2.

  • I've said this many times. Scientists and engineers need to aggressively develop geoengineering solutions, because humanity is going to need them. Our species isn't going to pull it's head out of it's ass until something catastrophic happens: entire farming regions turning into desert, coastal cities rendered uninhabitable, heat waves that knock entire power grids offline, cooking 10s of thousands of people to death because it's literally impossible to live if the dew point gets above 100 F. Stuff like th
    • So be it. in 400 years most of humanity will probably be living in the arctic, which will be a balmy 80 degrees.
      Seriously, the stupidity on /. is just beyond my comprehension.

      In winter both arctics will be as cold as always. Polar night, you know ...

    • by gweihir ( 88907 )

      Well, it will be far too late when the catastrophes become obvious. Geoengineering on this scale is a > 100 year project and it requires global peace and collaboration. There is no chance of that happening with the collection of fuckups that populate this dirtball.

  • Anyone following climate science knows that once the mass public is worried it's already too late! At that point we will be launching reflectors in space. I;ve expected this all along! We will literally need mirrors to have earth be hospitable to humans in 2100.

    You would need people to be proactive instead of reactive but sorry .... human beings ... I mean homo sapiens are litterally geared to be reactive.

    So when you have smart homo spaiens saying who cares to the dumb ones (99% of the population it seem

  • No shit Sherlock! (Score:5, Insightful)

    by jenningsthecat ( 1525947 ) on Thursday November 12, 2020 @11:15PM (#60718432)

    I pretty much arrived at this conclusion at least two years ago. Even then we were hearing about the Arctic melt releasing methane and the rapid acceleration of deglaciation. At that point it seemed pretty obvious we had passed the point of no return.

    Even if we could "suck CO2 out of the atmosphere" and sequester it, I think we'd have to do it really soon and really fast - otherwise warming caused by already-rising methane emissions might outstrip the effects of CO2 removal. And that doesn't even account for the rapid loss of the rainforests and whatever unmodeled / unforeseen negative effects that will have.

    Yes, we still need to mitigate AGW as best we can. But we also need to start preparing now for the massive waves of environmental refugees that have already begun in response to the effects of AGW. And it's time to get more serious about protecting, re-shaping, or outright moving coastal communities both large and small. Shifting hunks of major cities farther away from the ocean is a pretty big undertaking.

    • This "Positive Feedback Effect" has been taught here in high schools at least since early 90s. At a certain point the atmosphere will trap more heat than reflect due to greenhouse gasses, causing an irreversible heating up of the earth. We may already be past that point. Effects take 20-30 years to be felt, so we have yet to witness what was put in the atmosphere the last 20 years.
      Regarding the environmental refugees, you also have the exponential population growth in places like Africa for example (it wil
  • "Vaccine may not end Covid19". These kind of dumb ass statements always have one thing in common: 'May'.
  • "Plant billions of trees"

    That's the least we can do -- We cut down 15 billion trees/year. We already cut down half our trees. We have 3 trillion trees left.

    "We can't breathe"

  • ... will still be better in the long run.

    Even if we don't really notice a difference in our own lifetime.

    • We're definitely will make things worse and more quickly before we even try to slow it down. Putting the brakes on this is possible, but there is a certain stopping distance that can't be negotiated any more.

  • by Solandri ( 704621 ) on Friday November 13, 2020 @01:30AM (#60718650)
    Though apparently [slashdot.org] nobody wants [slashdot.org] to hear it [slashdot.org]. The only real solution is carbon sequestration, which the environmental movement opposes because they automatically assume anyone promoting it is doing so as a way to continue burning fossil fuels. You have to understand that renewables do not remove accumulated CO2 from the atmosphere. Renewables are like having perfect defense in a basketball game. It can let you win the game as long as you're ahead. But once you start losing, it cannot win you the game. At that point you must go on offense to win, which means carbon sequestration.

    Pilot tests of pumping CO2 underground [slashdot.org] has show that it mineralizes [usgs.gov] far faster than anyone expected - within 2 years in the test, rather than a thousand years as expected. For reference, the world pumps about 40 gigatons of CO2 into the atmosphere every year. So the 3000 gigatons the USGS estimates could be sequestered this way in the U.S. alone would account for 75 years of global CO2 production. And to address the points which have been brought up against this in the past:
    • No the CO2 can't leak back out. At the ambient temperatures and pressures found where it's being injected underground, CO2 is in the supercritical fluid phase [slashdot.org]. The only time it can convert into a gas is if the well bore springs a leak while it's still connected to the surface, exposing it to sea level pressure. Once the well is capped, a leak in the rock won't result in it suddenly converting into a gas which bubbles to the surface. it will just result in fluid CO2 flowing from one side of the rock to the other. This would actually be desirable since it would increase the amount of rock surface area the CO2 is exposed to, and thus accelerate the mineralization process.
    • No planting trees doesn't sequester CO2. When the tree dies and decomposes (its cellulose consumed for energy by microorganisms), that carbon is released back into the atmosphere as CO2. I really have to facepalm at this argument, since the people making it are usually the same ones shooting down my idea to stop recycling paper, and start burying it in landfills (or abandoned coal mines) in a slightly acidic slurry to prevent decomposition (akin to how peat bogs form [wikipedia.org]) as a method of carbon sequestration. Apparently in their minds, trees destined to decompose sequester CO2, but dead trees which you prevent from decomposing don't.
    • The cost to do it is not prohibitive [slashdot.org]. My back of the envelope calculations say it'll increase the cost of electricity or gasoline by about 50% in the U.S. For electricity in particular, that would still leave U.S. electricity cheaper than most of Europe. Note that adding the cost of sequestration to fossil fuels increases its price, which makes renewables and nuclear more cost-competitive.
    • No planting trees doesn't sequester CO2. When the tree dies and decomposes, that carbon is released back into the atmosphere as CO2.

      It does, though. When that tree dies, another one grows in its place. If we have X trees now, increase that to 2X and keep it there, we'll have twice the amount of CO2 sequestered in those trees, a significant amount.

    • Overly optimistic - seriously, this isn't Minecraft, where everything works perfectly as expected. First, mineratlization:

      Pilot tests of pumping CO2 underground [slashdot.org] has show that it mineralizes [usgs.gov] far faster than anyone expected

      Mineralization may happen quickly initially, but only in suitable minerals, and only as long as those minerals have not already absorbed as much CO2 as they are capable of. The amount any one location can absorb is strictly limited - these are not infinite sinks.

      Th

  • by blindseer ( 891256 ) <blindseer@eartBO ... minus physicist> on Friday November 13, 2020 @05:01AM (#60718906)

    With more CO2 in the air plants become more efficient in taking in CO2. This means areas of land not suitable for plant life with today's CO2 levels becomes suitable for plants with next year's CO2 levels.

    With warmer temperatures there's, again, more arable land. This also brings longer growth seasons. All more opportunity for plants to convert CO2 into plant matter, removing it from the atmosphere.

    Then there is the largest CO2 sink of them all, the sea. At the bottom of the sea are deposits of basalt and other minerals capable of reacting with CO2. In the water are plants capable of turning CO2 into plant matter. Plant matter that if eaten becomes animal matter, if not eaten then eventually sinks to the sea floor where it is effectively removed from the ecosystem.

    The planet has seen far more CO2, far less CO2, far higher and lower temperatures. This includes times humans have existed on this planet. All this time life continued.

    Don't worry too much, we'll be fine.

    • Re:We'll be fine. (Score:4, Insightful)

      by Graymalkin ( 13732 ) * on Friday November 13, 2020 @12:25PM (#60720136)

      Holy shit this is manifestly stupid. First and foremost, when the Earth was warmer in the past it didn't have eight billion humans depending on agriculture and industry. The warming and cooling trends also occurred over thousands of years so floral and faunal responses were gradual.

      We're seeing climate changes now on the scale of decades. Besides humans and animals not having a lot of time to adapt there's a number of ecological problems tied to temperature. We're already seeing rapid thawing of permafrost in the northern hemisphere. These permafrost melts are turning into methane spewing bogs, methane that's a far more powerful greenhouse gas than carbon dioxide.

      Greenland's ice sheet's melting is also accelerating. It will end up disrupting the Atlantic Conveyor which will drastically alter the climate of Europe and the US not to mention effects on already depleted or damaged fisheries. Increased atmospheric CO2 also increases CO2 in the ocean increasing its acidity. Increased acidity is already affecting marine food chains.

      While humans as a species and plants will "survive" increased atmospheric CO2 levels, current industrial civilization was built with 1850s climate and ecology in mind. The next century will see hundreds of trillions of dollars spent trying to adapt to the environment we fucked up. Hundreds of millions to billions of people are going to displaced because where they used to live flooded or dried out or is just uninhabitable. We'll be able to do some geoengineering to put a band aid on things but for every success we'll likely also end up with more Aral Sea disasters.

      Humans as a species surviving global warming isn't a question, it's human civilization surviving that's the real problem. Lots of agriculture and industry is sited for climates and ecologies that no longer or will cease to exist in those locations. It doesn't matter if plants can use CO2 if there's no water or it's too hot for them to grow.

  • According to the U.S. Energy Information Administration (EIA) and British Petroleum's Statistical Review of World Energy, we have 47 years of oil left. That's within many of our lifetimes, and if not yours then definitely your children/grandchildren.

    Imagine what running out of oil would do to the economy?

    Yes, this is only proven oil reserves. But we can't rely on actually finding more, and even if we do find more, that's just delaying the inevitable - fossil fuels are going to run out.

    So, we need to transition off of fossil fuels, and the sooner we start that transition, the easier it'll be on the economy.

    sources:
    https://www.worldometers.info/oil/
    https://www.eia.gov/
    https://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy.html

Marvelous! The super-user's going to boot me! What a finely tuned response to the situation!

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