We should remember that we are currently in an ice age[1]. If climatology can be reduced to an effective engineering practice that would be awesome, but we should remember that a frozen Earth will be far worse for most human beings than a hothouse Earth. In the worst case scenarios of Global Warming, the burdens and costs will be largely born by the developed world, both in terms of geographical changes such as sea level rise as well as absorbing migrants from more southerly regions. And the developed world is up to those challenges. On the other hand, when, not if, the reglaciation occurs, it will be devastating to the entire human population of the planet. It would be darkly comical if unintentional human warming were staving off the next freezing period, and we brought catastrophe on our planet by trying to fix it. Humility is called for.
For added reference, this is due to astronomical[1], atmospheric, and tectonic causes [2]. Obviously human beings have no control over astronomical or tectonic factors. The claim that the atmospheric factor can override both the astronomical and tectonic factors isn't implausible, but it should be understood that the atmosphere isn't the only or even the primary factor determining the climate.
The distinction between proximate and ultimate causes is deeply relevant for science and scientists.
For instance, when oceans change, such as el nino, la nina, reversals of enduring currents, or even new connections between seas due to tectonic transformations, that is properly a cause of climate change -- regardless of how much that change is, in fine, mediated by the atmosphere. Atmospheric changes are demonstrably not the only, nor the ultimate causes, of climate change.
The worst case scenario is more like a "Clathrate gun" doomsday. While the worst case is improbable, I do believe the priors you use to evaluate the risk and cost of global warming might be a bit optimistic. And it seems contradictory to say that the brunt of costs will be paid by the developed world and then admit that the costs include the migrant from locations on Earth rendered uninhabitable. Lastly, you are assuming that the political climate will permit us to deal intelligently, compassionately, and fiscally efficiently with migrants. The current political climate seems to contradict that assumption.
May as well worry about the solar wind blowing the atmosphere away. That's also possible after all.
It's surprising to me that in a technologically astute and optimistic forum like this one, there would be so much resistance to the idea that engineering solutions to heating would be easier than engineering solutions to cooling. Because anthropogenic or not, the climate is going to change, and keep changing, so either we adapt, we engineer it, or we die.
You missed my point. Of course it would be great to have a solution for every eventuality. However, the climate rapidly warming is the imminent danger. And it is the rate of change, not the final value, that is the most worrisome.
If we were to somehow go too far in the other direction, undoing all that CO2 removal wouldn't even be a challenge -- It'd be a return to the current status quo.
God help us when the fraction of gases in the atmosphere can be set by the political process. How often do we get a ruling class that you would trust with that decision? And if we can't trust them consistently on that, it may become our species' resolution of the Fermi paradox.
This is a bit bombastic. Democracies are not perfect, but they have been mostly functional, and the ruling class (while not great) does not have such a bad record: ozone depleting chemicals, leaded gasoline, OSHA rules, drug and food safety standards. Just like you, I am disappointed by the slow progress, but if we are to be taken seriously with our concerns we should not exaggerate.
It doesn't seem particularly fraught with ambiguity? We know what the composition was going back many hundreds of years. Presumably it would not be hard to agree something like, "OK we target the pre-industrial revolution composition" and that would be that.
This seems like a particularly bold claim given that we currently live in a political climate where we can’t even seem to agree on basic matters of reality.
We should remember that CO2 is an essential fertilizer for plants and phytoplankton, all of which thrive when there is much more CO2 in the atmosphere. Their photosynthesis processes evolved in and are ideal for an environment with CO2 concentrations at least 5-10x the current levels.
At or below 150 ppm of CO2 in the air, all land-based plants would go extinct.
Perhaps only if we consider CO2 in isolation without attendant water, temperature, and mineral stresses. And perhaps not on longer time scales [0]. And perhaps not everywhere [1].
They might thrive, if and only if, they can move to an area where they have their needed heat, water and light exposures. If atmospheric CO2 is 5x or 10x everything will need to be migrating an awful lot of miles northwards. To soils and locations that may not be suitable for ph or mineral reasons. Plants almost certainly can't migrate fast enough for current rates of change, let alone more. So there's agriculture screwed.
At or above 1,000ppm, or 2.5x current outside levels, human performance starts to decline. People will complain of drowsiness and stuffiness. Those levels can occur in buildings already. I don't look forward to a future where opening a window for fresh air delivers stuffiness, and inside buildings rise commensurately.
Who knows how many pollinating species will go extinct, and at what levels, as they can no longer breathe enough to fuel their activities.
> Their photosynthesis processes evolved in and are ideal for an environment with CO2 concentrations at least 5-10x the current levels
Wait a second. For the last few million years CO2 levels have been in the 180-300 ppm range (except for recently where they have gone above that).
What makes you think that plants that initially evolved hundreds of millions of years ago in very high CO2 environments did not continue evolving as CO2 levels changed, so that the plants we now have find 180-300 ppm to be ideal?
The two photosynthesis paths that evolved in land-based plants (C3 and C4) are very specific, not adaptable. There has been no such thing as further "evolution" of these chemical/physical processes in plants.
This is completely false, misleading information. Disappointing to see it is at the top. Different plants have varying levels of ideal co2 concentrations, and many do worse when they are higher than now. Not to mention since co2 will change temperature and weather, the net effect could be bad for a given plant even if the plant would thrive with more co2 in isolation.
My main point is that if CO2 levels fall below 150 ppm there would be a mass extinction of land-based plants, and of all the animals who depend on this vegetation. If you care about life on the continents, and human life, this is a valid concern when people explore schemes to rapidly remove massive quantities of CO2 from the atmosphere.
CO2 is one variable of many. Temperature is more important because it determines what enzymes can work efficiently. It's unlikely that current plants would survive the accompanying temperature changes that would occur if CO2 significantly increases.
Maybe we should go by scientific facts? plants thrive in warmer climate and higher CO2 levels, not in colder climate and at starvation levels of CO2. I suggest you look into the operations of commercial greenhouses, then study the temperature and CO2 records matching the origin and evolution of plants going back to hundreds of millions of years ago.
Yes, I certainly think we should follow basic logic. I worked at a greenhouse. Historical data is obviously not based on current plant genetics. Do you think people use a greenhouse in midsummer? There is clearly a maximum temperature that varies for different plants. I suggest you look up the thermodynamics of CO2.
Yes, there are many commercial greenhouses that operate year-round, including the summer months. The deliberately increased level of CO2 in a commercial greenhouse has no measurable thermodynamic impact.
Sure, but we want it to be in the 200 to 300 area instead of 400 ppm. No one is proposing killing all plants. We know plants do just fine at that concentration.
Yes, CO2 is what plants eat, but it doesn't tend to be the limiting nutrient very often on Earth today. For the ocean (where 50-85% of photosynthetic oxygen production, and equivalently carbon burial, happens [1]) there are actually maps of this [2], and you may note that CO2 does not appear. On land, it's usually water, nitrogen, or phosphorus [e.g., 3].
Accordingly, there have been many studies on CO2 fertilization, but since it's not the limiting nutrient it doesn't tend to have much of an effect [e.g. 4]. At best there are benefits for some plant species in areas where water is the limiting nutrient, since higher CO2 means plants can keep their stomata closed more [e.g. 5], but even this is a bit of a mixed bag since dry places tend to get hotter and drier under global warming.
Biologist here. I have a simple question in response to your disinformation: What CO2 level is used in commercial greenhouses?
All scientific, controlled experiments with plants demonstrate conclusively that they thrive (faster growth, larger leaves, increased biomass, larger fruits, less need for water, etc.) at higher CO2 levels than what we have today and than we had before the Industrial Revolution. I encourage people who are intellectually curious and honest to look up the scientific papers on the topic and read them for themselves (you don't have to be a biologist or a geologist to understand the experiments, the parameters, or the outcomes).
GP said that CO2 was not the _limiting factor_. I took this to mean that something else is often the bottleneck, such as access to nutrient matter. Presumably in a greenhouse, more CO2 can be used because other bottlenecks are reduced.
> since higher CO2 means plants can keep their stomata closed more [e.g. 5]
And that apparent silver lining's actually got a downside, too. Plants working hard to draw up water is a Good Thing, because that water is the only source of nitrogen and other elements needed to make proteins and vitamins.
CO2 just gets turned into carbs; it makes plants grow big and tall but less nutritious. This won't be a problem for us overfed gluttons in the West, but it is going to exacerbate malnutrition issues in poorer regions of the world.
It is not "misleading" when the scientific evidence collected via NASA's satellites is that CO2 fertilization has been measurably greening the continents for decades: "From a quarter to half of Earth’s vegetated lands has shown significant greening over the last 35 years largely due to rising levels of atmospheric carbon dioxide." [1]
Anyone who studies the biology and evolution of plants, as well as the actual constraints of their growth processes, will understand why this gigantic transformation has been happening. There are similar measurements of major increases in ocean plankton over the last decades.
That's a cool study. CO2 fertilization is a real phenomenon (with some caveats, which I pointed out some of), but I stand by the characterization that it is misleading to use this to suggest that we shouldn't be concerned about (or consider reversing) anthropogenic CO2 emissions, or to suggest that plants are maladapted and struggling without "CO2 concentrations at least 5-10x the current levels". Plants, algae, and cyanobacteria have had plenty of time to evolve carbon concentrating mechanisms [1] to help offset low atmospheric CO2.
Personal attacks, which you posted here and elsewhere, will get your account banned here. Please post civilly and substantively, or not at all—regardless of how wrong someone is or you feel they are.
While it is correct that this one particular comment of mine was inappropriately posted in anger at (perceived) dishonesty, please substantiate your statement that I have posted personal attacks "here and elsewhere".
I had a related thought that maybe someone here can answer. We've been approaching peak phosphorus, where we're using up the easy sources in much the way we do with oil. Like oil, we'll likely just find other sources as scarcity raises the price. Also like oil, the used product ends up distributed in the environment.
My question is, if photosynthetic carbon capture is nutrient limited, what happens when we are adding both CO2 and phosphorus to the environment? Does everything grow better? And what's the next limiting nutrient?
That's a good question. Someone else may be more qualified, but here's a start. For one thing, the answer will be a bit be different in marine vs. terrestrial ecosystems.
Nitrogen limitation is one common one, which can apply either on land or in the oceans in different areas. We're adding quite a lot of that to the environment too though, up to a 200% increase in reactive nitrogen availability over pre-Haber-Bosch times [1]; accordingly about half the nitrogen in your body may come from the Haber-Bosch process [2].
In the ocean, there are already a good number of places that are Fe limited (Fe is needed to make chlorophyll, among other things [3]), so they'll stay that way unless we go with Fe-fertilization or increase dust input [4].
Si limitation is another possibility in the oceans -- particularly for phytoplankton that make silica tests like diatoms [5] (though as an interesting aside, a surprising number of plants need silica to make their phytoliths [6])
On land, there's plenty of Fe and Si (from soil), so if we're supplying P, N, and CO2 then we're mostly left with water or light (photon) limitation.
If all nutrients are superabundant (particularly in aqueous settings), then we end up with runaway growth and eutrophication, which is dangerous in its own way [7]
CO2 from the air ends up being absorbed in the oceans. It's really just about; what is the most efficient way to remove CO2 from the carbon cycle. Currently removing from the air has appeared most promising. Perhaps that will change in time.
The largest and, long-term, most effective carbon sink are phytoplankton. They are responsible for half of all photosynthesis, thus absorbing tremendous quantities of CO2. As they individually die, they over millions of years accumulate thick carbon-filled layers at the bottom of oceans. This is the ultimate origin of oil deposits, by the way.
At a pH of ~8, the majority of dissolved inorganic carbon (DIC) exists as bicarbonate. Inorganic removal of a mole of HCO3- from surface seawater via precipitation of CaCO3 yields a mole of CO2 back to the atmosphere. Easier to fix CO2 via the classic silicate weathering reaction, which grabs 2 moles of CO2 per mole of silicate weathered (using CaSiO3 as a trivial example). This is the essential feedback from continental weathering: the Earth's thermostat.
And then release it back when it dies, biomass sequestering doesn’t work well unless you can find something that would not decompose and then you need to figure out what to do with it.
How do they release it back? A process that takes a few hours (burning) or a process that takes years? How did the hydrocarbons get in the ground in the first place?
You can't be serious with "something that would not decompose". Entropy literally disfavors it. The point is to tamper the rate, not to completely turn all C into diamond and jettison it into the sun.
Removing CO2 might be necessary to stop global warming.
But what chance does this sort of ambitious effort have when more and more states don't even want to deal with the ordinary problem of reducing CO2 output?
It seems to me that anyone caring about climate change needs to have a generally pro-science position politically.
I'm going to give an unpopular opinion that doesn't get voiced very often. And that is that climate science sucks. There exist fundamental truths that I believe we can all agree on.
The green house effect is real
Humans spew things into the atmosphere that increase the greenhouse effect
Therefore, we can safely say that humans are contributing to an effect that causes the earthto warm.
The problem is that quantifying that effect is pretty much impossibly difficult to the level of detail that we need to make informed decisions about long term policy. And anyone who believes otherwise is bullshitting themselves. There are lots of reasons to burn less fossil fuels, but throwing in reasons that are based on bad science detracts from those efforts.
To be clear, claiming that we know the earth is going to be 3 degrees warmer in 100 years (pick whatever numers you want) is preposterous. As people who develop models we must all know heep inside that we can make them say whatever we want. And if you make them say what the politicians want, you get more funding.
There is good science mixed in, but the problem we have is that (I'll use the US example) the left believes that the sky is falling because it's a convenient argument to arouse people into protecting the environment. And the right are in the pockets of oil companies, and will say whatever they're told to.
So, should we do the right thing (protect the environment) for the wrong reasons? I would argue no, because eventually nature will prove us wrong and the battle will be that much harder.
The reason that nothing changes is because the right can point to bad science, and they are right. We owe it to ourselves to do better
I agree. Most of the time when the science is settled, it’s settled. For example all scientists knew that once we figured out black body radiation Newtonian physicist is complete. Nothing new was required. Even Lord Kelvin proclaimed that simple outstanding problem was entirely explainable by the physics of his day.
Yeah, once physicists figured out quantum mechanics, cannon makers and bridge builders cried in dismay, because their previous measurements - based on previously trusted Newtonian mechanics - stopped working.
"Serves them well!" people snickered. "Risking one's career on unsettled science!"
You're not listening, and that is part of the problem. We cannot have discussions, because the politics have polarized us. I'm not arguing that the earth isn't warming. I'm not arguing that humans aren't involved. I'm saying that there is a detrimental feedback loop between politics and science. This feedback loop means that we can't have reasonable discussions. Dismissing dissenting views as "climate change deniers" is a problem for science. And FWIW, though I'm a nobody, I have had private dinners with people who are somebodies (also, I respect that I'm an anonymous user on the internet which definitely helps my credibility - but I'll try anyway) - the people who have written IPCC reports and been in climate science research for decades. They share the opinions that I'm expressing, but dare not say them because they need grants; it's a delicate balance. The political feedback loop is a problem. It gets in the way of good science. Using predictive models can give us insight, but nature is pretty good at making fools of humans, and it's arrogant to believe that we can predict the future of something like the weather given the nature of the problem - we can't run controlled experiments, the data is super noisy and difficult to wrangle, and
Without trying to get into a flame war here, this claim is very iffy. As a scientist myself, there's (for better or worse) nothing better to make a career out of than showing where other scientists have made a mistake.
Science doesn’t work like that: “As people who develop models we must all know heep inside that we can make them say whatever we want.”
You don’t like the assumptions the model made? Fine, make an argument as to why they’re the wrong assumptions or the model is flawed. The model with the best predictive power wins the day.
The irony being that IPCC models have a terrible track record of predictive success. So it seems maybe the best models dont win, but rather the most politically beneficial model wins
I believe in the basic consensus that the earth is warming due to human activity. Getting the magnitude right is very hard though, because it’s a complex system, we only have one data series, we have never experienced current or future conditions before, we can’t do controlled experiments, and our data is noisy and sometimes difficult to calibrate. This puts you in a situation where you may be able to predict direction accurately, but magnitude is very tough. Methane from melting permafrost and hydrates at the bottom of the ocean are just two examples that might cause a gross underestimate of warming impact.
The error bars are not large enough to be seriously confident that the problem can be ignored, though.
Basically everything we have says that:
* Humans are causing basically all of the warming happening, either directly or indirectly
* All of that warming will eventually be enough to kill most or all of us within 40-100 years, especially if nothing is done, but even still eventually if we stick to current commitments.
There's literally no reason to faff about anymore - we have direct, quantifiable evidence that people are being killed and displaced by climate change related events today, and it will only get worse as time goes on. Hurricanes are stronger, wild fires are wilder, sea levels are rising and driving people off of low lying islands, glaciers are melting, the northwest passage has stayed opened for literally the first time in living memory, coral reefs are overheating to death, species are migrating north or just straight up going extinct. This is a problem now and immediately that the human race needs to address in force.
"All of that warming will eventually be enough to kill most or all of us within 40-100 years." Given current human life expectancy, it is true that the vast majority of humans alive today will be dead in 100 years, but that is not your claim. You are asserting that continued, slow warming will directly kill most or all humans within the next 40-100 years. No scientific prediction, no IPCC report, matches that.
Exaggeration is counter-productive and dishonest, not a virtue.
With respect to global warming, I don’t think we’ll get there politically. There are too many people and politicians that either don’t have a scientific worldview or are on the payroll (so to speak, not literally but via campaign funding) of fossil fuel companies.
We may, however, get there via improved economics and technology happening in renewable energy right now. With an unreasonable amount of luck, we might buy ourselves enough time to make peace with the human condition and find a replacement for global capitalism that does a better job of integrating the reality of our needs and the planet’s.
Politically we have subsidies. Economically subsidized competition. It’s all very feasible and can be done rather quickly. We did / are doing it with wind and solar and can do so with negative carbon.
> Removing CO2 might be necessary to stop global warming.
> But what chance does this sort of ambitious effort have when more and more states don't even want to deal with the ordinary problem of reducing CO2 output?
There are cheaper geo-engineering methods that don't attempt to directly reverse the problem, just (locally) mitigate some of the consequences, that could be done unilaterally by a state. E.g. stratospheric aerosol injection (less glamorous but a much cheaper than parking sunlight-filtering-satellites between the earth and the sun).
> Unlike the control of greenhouse gas emissions, which must be undertaken by all major
emitting nations to be effective and is likely to be costly, geoengineering could be undertaken quickly and unilaterally by a single party, at relatively low cost. Unilateral geoengineering, however, is highly likely to impose costs on other countries and run risks with the entire planet’s climate system.
Did you read the article? The person interview specifically mentions aerosol injections and possible unforeseen consequences of bio-engineering. It seems rather stupid to duct tape your leaking ship knowing that you’ll arrive at the port soon.
i didn't read the article, but i did attend a couple of lectures last year about geoengineering proposals.
i agree that e.g. aerosol injection proposals seem rather stupid, won't actually fix the problem, but may just mitigate some of the many consequences of the problem, and also cause entirely new problems.
on the other hand, i suspect it is much more likely that geoengineering proposals will actually happen in preference to hypothetical negative emission technology, as geoengineering doesn't need a group of countries to agree on doing it, and (some of them) are relatively cheap and easy to do using existing technology.
I'm reading "The Ends of the World: Supervolcanoes, Lethal Oceans, and the Search for Past Apocalypses" by Peter Brannen. Most of the book focuses on past mass extinction events, but there's a bit of discussion and comparison to what's going on in the world now. It's written in a fairly popular-science-y style, but there's lots of references to further reading. Some quotes:
> [...] humanity has not yet come anywhere even remotely close to the death tolls of the major mass extinctions of the past half-billion years ... yet. In the past 400 years, there have been documented extinctions of some 800 species. This is a tragedy, to be sure, and likely a massive undercount, but when divided by the 1.9 million species known, 800 extinct species amounts to an extinction of less than one-tenth of 1 percent - a far cry from the End-Permian, during which, generously rounding up, almost 100 percent of complex life on earth was killed.
re: the End-Permian mass extinction
> "Five hundred million years is a really, really, _really_ long time. And [the End-Permian mass extinction] is the single worst event in the last 500 million years of earth history. So your scenario should not be sort of a bad-day scenario. [...] It's closer to a one-in-a-billion event."
> [...] End-Permian sites across the planet from the ancient ocean [...] similarly recorded a carbon cycle jackknifing. Where did all this extra light carbon in the atmosphere come from? One way is to kill all the plants, plankton, and animals in the world. [...] But the carbon isotope swing at the End-Permian mass extinction is so severe that many other scientists think that the collapse of the biosphere isn't enough to explain it.
> [...] At the end of the Permian, Siberia briefly turned inside out as the Traps covered Russia in more than 2 million square miles of lava.
> [...] "Basically the entire global economy rests on how quickly we can get carbon out of the ground and put it in the atmosphere", Ridgwell told me. "That's basically the global enterprise. And there's a lot of people doing it. Geologically, it's a really impressive effort."
> But as exceptional as humans are, estimates of the carbon released in the End-Permian mass extinction range from an utterly catastrophic 10,000 gigatons of carbon -- twice as much as we could ever burn -- up to a mind-meltingly unfathomable 48,000 gigatons.
> [...] "So taking the modern ocean and adding 40,000 gigatons of carbon -- like in the End-Permian -- it would take you from, say, 300 ppm to 30,000 ppm CO_2," Payne said. We both started laughing. This number is incomprehensible.
> [...] For now, typical estimates place End-Permian atmospheric carbon dioxide somewhere around 8,000 parts per million [...]
> [...] In the long term the oceans can keep up with a huge buildup of carbon dioxide in the atmosphere, as long as it happens slowly enough. The gradual process of weathering breaks down rocks on land, washing them into the ocean and, in doing so, buffer the seas against acidification [...]"
> "Well, the rate at which we're injecting CO_2 into the atmosphere today, according to our best estimates, is ten times faster than it was during the End-Permian. And rates matter. So today we're creating a very difficult environment for life to adapt, and we're imposing that change maybe ten times faster than the worst events in Earth's history".
For reference, the human endeavour is injecting roughly 40 gigatons of CO_2 into the atmosphere every year.
Wouldn’t the feedback loop effect significantly accelerate injection rate beyond the estimates 10x? My understanding is that matters compound faster and faster as issues grow problematic.
> "Well, the rate at which we're injecting CO_2 into the atmosphere today, according to our best estimates, is ten times faster than it was during the End-Permian. And rates matter. So today we're creating a very difficult environment for life to adapt, and we're imposing that change maybe ten times faster than the worst events in Earth's history".
Geologist here! That's a good quote. On geologic timescales, a million years is short! Accordingly, a lot of our effects on the environment are scary more because of their rate than their absolute magnitude (so far). I think humanity as a species has been doing a pretty good job of implementing that old facebook motto "move fast and break things". We'll see how that works out for us.
I wouldn't mind living in this future. I'm haunted by a beautiful idea:
Imagine standing outside in sunlight. Above the clouds in the course of the sun is a faint band a bit wider than the sun. Specks, motes. Thousands of them. Across the band some glitter, some are dark - like dark specks. Those covering the sun are almost all dark. If you carefully look at them through a filter that let's you see the sun's disk, you can make out a fuzzy outline not too unlighy the continents, with a few extra spots in between.
Earth has a ring. An artifical one, much wider than the ones Saturn has - more like a ribbon, actually. The motes are each large flat reflective surfaces. Flat disks made of reflective plastic films. Microns thick with as much area as is practical to make launch and unfold at scale. They orient themselves using current flowing around their rim using electricity generated from solar power on their main body. The current in the rims orient them relative to earth's magnetic field. They also act like solar sails when needed, using solar wind for minor maneuvering and they use small micro ion drives for positioning.
Each is a pixel. It can reflect sunlight completely away from the surface of the earth. Or to a targeted spot on it. They can match their rotation to their orbit and cast a variable shadow: from a slim wisp to their full area.
All in all. All of them together can dim the sunlight falling on the earth by up to 2%, but with precise control per region.
Many targeted on the same spot can boil (or slowly evaporate) large bodies of water or heat large volumes of air within specific control.
They can be weapons. Terrible ones: melting metal and rock for small focused regions.
But mostly they are tools - gardening tools.
Weather, and more importantly climate is something that they are used to steer. After wrecking the sort of balance we found when we started here we were responsible for establishing a new balance.
Most of their work is reducing the incident solar radiation falling on the earth's surface. They dim the radiant energy on the surface in line with the current climate control program. For the continents they mostly just reduce incoming energy. Over the ocean some areas are dimmed less to help cloud formation. This extends their influence immensely as we then increase the earth's albedo using the extra cloud cover, reflecting a lot more light than ocean does. They fiercely shield whatever glaciers we could save. The ones on the night side are used for controlled lighting in a few cases. The baby drone-planted forests are sometimes given extra sunlight. And a few cities are given the occasional extra light when safe.
The ones not positioned for blocking sunlight focus light and heat to manage weather systems. Parts of the garden's weather systems can be managed. On the one side of a continent clouds are formed by heating the ocean. These clouds are shielded and shepherded through shielded corridors and allowed to condense and rain in the interior.
In places large inland water bodies were made. In other places river like canals were melted through rock.
The natural forests and areas we could save are given special status:Bonsai, and we try to keep them vaguely in line with what they originally were, at great cost. But much desert is farmable and a lot of previously rough terrain is being manicured. Some spots of the garden are never tame and recalcitrantly fights back.
There is a degree of success in using them to manage ocean currents, but it's difficult and doesn't always work. They don't have the strength and finesse required to do that at scale. We need other tools for that.
Wind currents are easier. They follow simple temperature gradients and with trial and error and a lot of computer modeling these are mostly directly managed. Weather is at a coarse (and often fine) level controllable within the constraints set by climate regulation control. A new stable balance against the current level of atmospheric composition can be maintained - wi...
Lol!
;-)
Um... Exactly!
I don't think real world problems are solved, we just exchange them for different ones.
You hope to go from: "there is no software for my platform" to "there is so much software for my platform it is hard to find a perfect fit" or "I'm so poor I can't afford to eat" to "I struggle to find an investment banker that I like to handle my investments".
Our current situation is sort of a consequence of:
Imagine a world where beasts of burden don't toil under the hot sun - where machines powered by refined oil products allow for the cultivation of crops, feeding millions.
Where machines relieve people of brutish work, freeing them for more satisfying and valuable pursuits.
Where durable and strong materials can be made cheaply from petroleum-based products that millions of households can enjoy.
Where hundreds of millions of people can be fed using more efficient agriculture that uses chemically produced fertilizer....
Jesus Christ hacker news, get your shit together. Way to many Climate Change denialists/minimizers here to be anything but appalling, considering the reputation of the site's user base.
Scientists agree: Climate change is terrifying, climate change is human caused, and climate change is here now today, threatening to be the effective end of our species in a number of decades you can count on your hands. On top of which, it only takes mildly pessimistic scenarios to reach time spans you will probably live to see.
83 comments
[ 2.1 ms ] story [ 120 ms ] thread[1]https://en.wikipedia.org/wiki/Quaternary_glaciation
[1] https://en.wikipedia.org/wiki/Interglacial
[1] https://en.wikipedia.org/wiki/Milankovitch_cycles [2] https://www.geocraft.com/WVFossils/ice_ages.html
For instance, when oceans change, such as el nino, la nina, reversals of enduring currents, or even new connections between seas due to tectonic transformations, that is properly a cause of climate change -- regardless of how much that change is, in fine, mediated by the atmosphere. Atmospheric changes are demonstrably not the only, nor the ultimate causes, of climate change.
https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis
It's surprising to me that in a technologically astute and optimistic forum like this one, there would be so much resistance to the idea that engineering solutions to heating would be easier than engineering solutions to cooling. Because anthropogenic or not, the climate is going to change, and keep changing, so either we adapt, we engineer it, or we die.
Right now the ruling class of big oil is setting the fraction of gases in the atmosphere, and doing a terrible job of it.
But at least it isn't the government?
This seems like a particularly bold claim given that we currently live in a political climate where we can’t even seem to agree on basic matters of reality.
At or below 150 ppm of CO2 in the air, all land-based plants would go extinct.
[0] http://science.sciencemag.org/content/360/6386/317
[1] https://www.nature.com/articles/nclimate2995
At or above 1,000ppm, or 2.5x current outside levels, human performance starts to decline. People will complain of drowsiness and stuffiness. Those levels can occur in buildings already. I don't look forward to a future where opening a window for fresh air delivers stuffiness, and inside buildings rise commensurately.
Who knows how many pollinating species will go extinct, and at what levels, as they can no longer breathe enough to fuel their activities.
Wait a second. For the last few million years CO2 levels have been in the 180-300 ppm range (except for recently where they have gone above that).
What makes you think that plants that initially evolved hundreds of millions of years ago in very high CO2 environments did not continue evolving as CO2 levels changed, so that the plants we now have find 180-300 ppm to be ideal?
Yes, CO2 is what plants eat, but it doesn't tend to be the limiting nutrient very often on Earth today. For the ocean (where 50-85% of photosynthetic oxygen production, and equivalently carbon burial, happens [1]) there are actually maps of this [2], and you may note that CO2 does not appear. On land, it's usually water, nitrogen, or phosphorus [e.g., 3].
Accordingly, there have been many studies on CO2 fertilization, but since it's not the limiting nutrient it doesn't tend to have much of an effect [e.g. 4]. At best there are benefits for some plant species in areas where water is the limiting nutrient, since higher CO2 means plants can keep their stomata closed more [e.g. 5], but even this is a bit of a mixed bag since dry places tend to get hotter and drier under global warming.
[1]https://en.wikipedia.org/wiki/Phytoplankton#Oxygen_productio... [2] https://media.springernature.com/m685/nature-static/assets/v... [3] https://nph.onlinelibrary.wiley.com/doi/full/10.1111/j.1469-... [4] http://www.pnas.org/content/early/2016/12/07/1610156113.shor... [5] https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.124...
All scientific, controlled experiments with plants demonstrate conclusively that they thrive (faster growth, larger leaves, increased biomass, larger fruits, less need for water, etc.) at higher CO2 levels than what we have today and than we had before the Industrial Revolution. I encourage people who are intellectually curious and honest to look up the scientific papers on the topic and read them for themselves (you don't have to be a biologist or a geologist to understand the experiments, the parameters, or the outcomes).
And that apparent silver lining's actually got a downside, too. Plants working hard to draw up water is a Good Thing, because that water is the only source of nitrogen and other elements needed to make proteins and vitamins.
CO2 just gets turned into carbs; it makes plants grow big and tall but less nutritious. This won't be a problem for us overfed gluttons in the West, but it is going to exacerbate malnutrition issues in poorer regions of the world.
See e.g.:
https://www.nature.com/scitable/knowledge/library/effects-of...
http://advances.sciencemag.org/content/4/5/eaaq1012
Anyone who studies the biology and evolution of plants, as well as the actual constraints of their growth processes, will understand why this gigantic transformation has been happening. There are similar measurements of major increases in ocean plankton over the last decades.
[1] https://www.nasa.gov/feature/goddard/2016/carbon-dioxide-fer...
My apologies if that isn't what you were doing.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2606764/
https://news.ycombinator.com/newsguidelines.html
My question is, if photosynthetic carbon capture is nutrient limited, what happens when we are adding both CO2 and phosphorus to the environment? Does everything grow better? And what's the next limiting nutrient?
Nitrogen limitation is one common one, which can apply either on land or in the oceans in different areas. We're adding quite a lot of that to the environment too though, up to a 200% increase in reactive nitrogen availability over pre-Haber-Bosch times [1]; accordingly about half the nitrogen in your body may come from the Haber-Bosch process [2].
In the ocean, there are already a good number of places that are Fe limited (Fe is needed to make chlorophyll, among other things [3]), so they'll stay that way unless we go with Fe-fertilization or increase dust input [4].
Si limitation is another possibility in the oceans -- particularly for phytoplankton that make silica tests like diatoms [5] (though as an interesting aside, a surprising number of plants need silica to make their phytoliths [6])
On land, there's plenty of Fe and Si (from soil), so if we're supplying P, N, and CO2 then we're mostly left with water or light (photon) limitation.
If all nutrients are superabundant (particularly in aqueous settings), then we end up with runaway growth and eutrophication, which is dangerous in its own way [7]
[1] https://en.wikipedia.org/wiki/Human_impact_on_the_nitrogen_c... [2] https://en.wikipedia.org/wiki/Haber_process#Economic_and_env... [3] https://www.tandfonline.com/doi/abs/10.1080/0190416840936323... [4] https://en.wikipedia.org/wiki/Iron_fertilization [5] https://www.sciencedirect.com/science/article/pii/S096706370... [6] https://en.wikipedia.org/wiki/Phytolith [7] https://en.wikipedia.org/wiki/Eutrophication
You can't be serious with "something that would not decompose". Entropy literally disfavors it. The point is to tamper the rate, not to completely turn all C into diamond and jettison it into the sun.
But what chance does this sort of ambitious effort have when more and more states don't even want to deal with the ordinary problem of reducing CO2 output?
It seems to me that anyone caring about climate change needs to have a generally pro-science position politically.
The green house effect is real Humans spew things into the atmosphere that increase the greenhouse effect Therefore, we can safely say that humans are contributing to an effect that causes the earthto warm.
The problem is that quantifying that effect is pretty much impossibly difficult to the level of detail that we need to make informed decisions about long term policy. And anyone who believes otherwise is bullshitting themselves. There are lots of reasons to burn less fossil fuels, but throwing in reasons that are based on bad science detracts from those efforts.
To be clear, claiming that we know the earth is going to be 3 degrees warmer in 100 years (pick whatever numers you want) is preposterous. As people who develop models we must all know heep inside that we can make them say whatever we want. And if you make them say what the politicians want, you get more funding.
There is good science mixed in, but the problem we have is that (I'll use the US example) the left believes that the sky is falling because it's a convenient argument to arouse people into protecting the environment. And the right are in the pockets of oil companies, and will say whatever they're told to.
So, should we do the right thing (protect the environment) for the wrong reasons? I would argue no, because eventually nature will prove us wrong and the battle will be that much harder.
The reason that nothing changes is because the right can point to bad science, and they are right. We owe it to ourselves to do better
The vast majority of scientists do agree that global warming is real and that humans are causing it.
Yet the go-to argument for deniers is to claim that the science is not there.
Not being a scientist myself, I have to assume that you're talking out your ass, and the scientists are correct.
"Serves them well!" people snickered. "Risking one's career on unsettled science!"
Without trying to get into a flame war here, this claim is very iffy. As a scientist myself, there's (for better or worse) nothing better to make a career out of than showing where other scientists have made a mistake.
You don’t like the assumptions the model made? Fine, make an argument as to why they’re the wrong assumptions or the model is flawed. The model with the best predictive power wins the day.
http://www.ipcc.ch/publications_and_data/publications_ipcc_f...
Basically everything we have says that: * Humans are causing basically all of the warming happening, either directly or indirectly * All of that warming will eventually be enough to kill most or all of us within 40-100 years, especially if nothing is done, but even still eventually if we stick to current commitments.
There's literally no reason to faff about anymore - we have direct, quantifiable evidence that people are being killed and displaced by climate change related events today, and it will only get worse as time goes on. Hurricanes are stronger, wild fires are wilder, sea levels are rising and driving people off of low lying islands, glaciers are melting, the northwest passage has stayed opened for literally the first time in living memory, coral reefs are overheating to death, species are migrating north or just straight up going extinct. This is a problem now and immediately that the human race needs to address in force.
Exaggeration is counter-productive and dishonest, not a virtue.
We may, however, get there via improved economics and technology happening in renewable energy right now. With an unreasonable amount of luck, we might buy ourselves enough time to make peace with the human condition and find a replacement for global capitalism that does a better job of integrating the reality of our needs and the planet’s.
> But what chance does this sort of ambitious effort have when more and more states don't even want to deal with the ordinary problem of reducing CO2 output?
There are cheaper geo-engineering methods that don't attempt to directly reverse the problem, just (locally) mitigate some of the consequences, that could be done unilaterally by a state. E.g. stratospheric aerosol injection (less glamorous but a much cheaper than parking sunlight-filtering-satellites between the earth and the sun).
> Unlike the control of greenhouse gas emissions, which must be undertaken by all major emitting nations to be effective and is likely to be costly, geoengineering could be undertaken quickly and unilaterally by a single party, at relatively low cost. Unilateral geoengineering, however, is highly likely to impose costs on other countries and run risks with the entire planet’s climate system.
https://www.cfr.org/content/thinktank/GeoEng_Jan2709.pdf
i agree that e.g. aerosol injection proposals seem rather stupid, won't actually fix the problem, but may just mitigate some of the many consequences of the problem, and also cause entirely new problems.
on the other hand, i suspect it is much more likely that geoengineering proposals will actually happen in preference to hypothetical negative emission technology, as geoengineering doesn't need a group of countries to agree on doing it, and (some of them) are relatively cheap and easy to do using existing technology.
> [...] humanity has not yet come anywhere even remotely close to the death tolls of the major mass extinctions of the past half-billion years ... yet. In the past 400 years, there have been documented extinctions of some 800 species. This is a tragedy, to be sure, and likely a massive undercount, but when divided by the 1.9 million species known, 800 extinct species amounts to an extinction of less than one-tenth of 1 percent - a far cry from the End-Permian, during which, generously rounding up, almost 100 percent of complex life on earth was killed.
re: the End-Permian mass extinction
> "Five hundred million years is a really, really, _really_ long time. And [the End-Permian mass extinction] is the single worst event in the last 500 million years of earth history. So your scenario should not be sort of a bad-day scenario. [...] It's closer to a one-in-a-billion event."
> [...] End-Permian sites across the planet from the ancient ocean [...] similarly recorded a carbon cycle jackknifing. Where did all this extra light carbon in the atmosphere come from? One way is to kill all the plants, plankton, and animals in the world. [...] But the carbon isotope swing at the End-Permian mass extinction is so severe that many other scientists think that the collapse of the biosphere isn't enough to explain it.
> [...] At the end of the Permian, Siberia briefly turned inside out as the Traps covered Russia in more than 2 million square miles of lava.
> [...] "Basically the entire global economy rests on how quickly we can get carbon out of the ground and put it in the atmosphere", Ridgwell told me. "That's basically the global enterprise. And there's a lot of people doing it. Geologically, it's a really impressive effort."
> But as exceptional as humans are, estimates of the carbon released in the End-Permian mass extinction range from an utterly catastrophic 10,000 gigatons of carbon -- twice as much as we could ever burn -- up to a mind-meltingly unfathomable 48,000 gigatons.
> [...] "So taking the modern ocean and adding 40,000 gigatons of carbon -- like in the End-Permian -- it would take you from, say, 300 ppm to 30,000 ppm CO_2," Payne said. We both started laughing. This number is incomprehensible.
> [...] For now, typical estimates place End-Permian atmospheric carbon dioxide somewhere around 8,000 parts per million [...]
> [...] In the long term the oceans can keep up with a huge buildup of carbon dioxide in the atmosphere, as long as it happens slowly enough. The gradual process of weathering breaks down rocks on land, washing them into the ocean and, in doing so, buffer the seas against acidification [...]"
> "Well, the rate at which we're injecting CO_2 into the atmosphere today, according to our best estimates, is ten times faster than it was during the End-Permian. And rates matter. So today we're creating a very difficult environment for life to adapt, and we're imposing that change maybe ten times faster than the worst events in Earth's history".
For reference, the human endeavour is injecting roughly 40 gigatons of CO_2 into the atmosphere every year.
Geologist here! That's a good quote. On geologic timescales, a million years is short! Accordingly, a lot of our effects on the environment are scary more because of their rate than their absolute magnitude (so far). I think humanity as a species has been doing a pretty good job of implementing that old facebook motto "move fast and break things". We'll see how that works out for us.
Imagine standing outside in sunlight. Above the clouds in the course of the sun is a faint band a bit wider than the sun. Specks, motes. Thousands of them. Across the band some glitter, some are dark - like dark specks. Those covering the sun are almost all dark. If you carefully look at them through a filter that let's you see the sun's disk, you can make out a fuzzy outline not too unlighy the continents, with a few extra spots in between. Earth has a ring. An artifical one, much wider than the ones Saturn has - more like a ribbon, actually. The motes are each large flat reflective surfaces. Flat disks made of reflective plastic films. Microns thick with as much area as is practical to make launch and unfold at scale. They orient themselves using current flowing around their rim using electricity generated from solar power on their main body. The current in the rims orient them relative to earth's magnetic field. They also act like solar sails when needed, using solar wind for minor maneuvering and they use small micro ion drives for positioning. Each is a pixel. It can reflect sunlight completely away from the surface of the earth. Or to a targeted spot on it. They can match their rotation to their orbit and cast a variable shadow: from a slim wisp to their full area. All in all. All of them together can dim the sunlight falling on the earth by up to 2%, but with precise control per region. Many targeted on the same spot can boil (or slowly evaporate) large bodies of water or heat large volumes of air within specific control. They can be weapons. Terrible ones: melting metal and rock for small focused regions. But mostly they are tools - gardening tools. Weather, and more importantly climate is something that they are used to steer. After wrecking the sort of balance we found when we started here we were responsible for establishing a new balance.
Most of their work is reducing the incident solar radiation falling on the earth's surface. They dim the radiant energy on the surface in line with the current climate control program. For the continents they mostly just reduce incoming energy. Over the ocean some areas are dimmed less to help cloud formation. This extends their influence immensely as we then increase the earth's albedo using the extra cloud cover, reflecting a lot more light than ocean does. They fiercely shield whatever glaciers we could save. The ones on the night side are used for controlled lighting in a few cases. The baby drone-planted forests are sometimes given extra sunlight. And a few cities are given the occasional extra light when safe. The ones not positioned for blocking sunlight focus light and heat to manage weather systems. Parts of the garden's weather systems can be managed. On the one side of a continent clouds are formed by heating the ocean. These clouds are shielded and shepherded through shielded corridors and allowed to condense and rain in the interior. In places large inland water bodies were made. In other places river like canals were melted through rock. The natural forests and areas we could save are given special status:Bonsai, and we try to keep them vaguely in line with what they originally were, at great cost. But much desert is farmable and a lot of previously rough terrain is being manicured. Some spots of the garden are never tame and recalcitrantly fights back. There is a degree of success in using them to manage ocean currents, but it's difficult and doesn't always work. They don't have the strength and finesse required to do that at scale. We need other tools for that. Wind currents are easier. They follow simple temperature gradients and with trial and error and a lot of computer modeling these are mostly directly managed. Weather is at a coarse (and often fine) level controllable within the constraints set by climate regulation control. A new stable balance against the current level of atmospheric composition can be maintained - wi...
Our current situation is sort of a consequence of:
Imagine a world where beasts of burden don't toil under the hot sun - where machines powered by refined oil products allow for the cultivation of crops, feeding millions. Where machines relieve people of brutish work, freeing them for more satisfying and valuable pursuits. Where durable and strong materials can be made cheaply from petroleum-based products that millions of households can enjoy. Where hundreds of millions of people can be fed using more efficient agriculture that uses chemically produced fertilizer....
And so on and so forth...
Scientists agree: Climate change is terrifying, climate change is human caused, and climate change is here now today, threatening to be the effective end of our species in a number of decades you can count on your hands. On top of which, it only takes mildly pessimistic scenarios to reach time spans you will probably live to see.